Early Elbow Flexion Contracture Predicts Shoulder Contracture in Infants with Brachial Plexus Birth Injury

OBJECTIVE

To determine if children who present with an elbow flexion contracture (EFC) from brachial plexus birth injury (BPBI) are more likely to develop shoulder contracture and undergo surgical treatment.

STUDY DESIGN

Retrospective review of children <2 years of age with BPBI who presented to a single children's hospital from 1993 to 2020. Age, elbow and shoulder range of motion (ROM), imaging measurements, and surgical treatment and outcome were analyzed. Patients with an EFC of ≥10° were included in the study sample. Data from 2445 clinical evaluations (1190 patients) were assessed. The final study cohort included 72 EFC cases matched with 230 non-EFC controls. Three patients lacked sufficient follow-up data.

RESULTS

There were 299 included patients who showed no differences between study and control groups with respect to age, sex, race, ethnicity, or functional score. Patients with EFC had 12° less shoulder range of motion (95% CI, 5°-20°; P < .001) and had 2.5 times the odds of shoulder contracture (OR, 2.5; 95% CI, 1.3-4.7; P = .006). For each additional 5° of EFC, the odds of shoulder contracture increased by 50% (OR, 1.5; 95% CI, 1.2-1.8; P < .001) and odds of shoulder procedure increased by 62% (OR, 1.62; 95% CI, 1.04-2.53; P = .03). Sensitivity of EFC for predicting shoulder contracture was 49% and specificity was 82%.

CONCLUSIONS

In patients with BPBI <2 years of age, presence of EFC can be used as a screening tool in identifying shoulder contractures that may otherwise be difficult to assess. Prompt referral should be arranged for evaluation at a BPBI specialty clinic, because delayed presentation risks worsening shoulder contracture and potentially more complicated surgery.

DNA-methylation signature accurately differentiates pancreatic cancer from chronic pancreatitis in tissue and plasma

OBJECTIVE

Pancreatic ductal adenocarcinoma (PDAC) is a lethal malignancy. Differentiation from chronic pancreatitis (CP) is currently inaccurate in about one-third of cases. Misdiagnoses in both directions, however, have severe consequences for patients. We set out to identify molecular markers for a clear distinction between PDAC and CP.

DESIGN

Genome-wide variations of DNA-methylation, messenger RNA and microRNA level as well as combinations thereof were analysed in 345 tissue samples for marker identification. To improve diagnostic performance, we established a random-forest machine-learning approach. Results were validated on another 48 samples and further corroborated in 16 liquid biopsy samples.

RESULTS

Machine-learning succeeded in defining markers to differentiate between patients with PDAC and CP, while low-dimensional embedding and cluster analysis failed to do so. DNA-methylation yielded the best diagnostic accuracy by far, dwarfing the importance of transcript levels. Identified changes were confirmed with data taken from public repositories and validated in independent sample sets. A signature of six DNA-methylation sites in a CpG-island of the protein kinase C beta type gene achieved a validated diagnostic accuracy of 100% in tissue and in circulating free DNA isolated from patient plasma.

CONCLUSION

The success of machine-learning to identify an effective marker signature documents the power of this approach. The high diagnostic accuracy of discriminating PDAC from CP could have tremendous consequences for treatment success, once the result from still a limited number of liquid biopsy samples would be confirmed in a larger cohort of patients with suspected pancreatic cancer.

Wrist Guards/Supports in Gymnastics: Are They Helping or Hurting You?

BACKGROUND

The prevalence of wrist pain among gymnasts ranges from 46% to 79%. To alleviate wrist pain, gymnasts wear wrist guards/supports (WG/S).

PURPOSE

To investigate the effect of WG/S on the wrist joint through joint moment, angles, total joint range of motion (ROM) arc, and ground-reaction force (GRF).

STUDY DESIGN

Controlled laboratory study.

METHODS

A cross-sectional study design was used to investigate 23 female gymnasts (mean ± SD: age, 12.3 ± 1.5 years; height, 143.4 ± 7.6 cm; mass, 37.7 ± 6.6 kg; body mass index, 18.6 ± 2.9) who performed back handsprings (analyzed by first half [phase 1] and second half [phase 2]) with the following 3 conditions: no WG/S, Skids/Ultimate Wrist Supports (S/UWS), and Tiger Paws (TP). Wrist joint moments, angles, total ROM arc, and GRF were examined by the 3 conditions using analysis of variance with Bonferroni correction and effect size (Cohen d).

RESULTS

For mean wrist flexion moment, both S/UWS and TP showed significantly higher values than the no-WG/S condition in landing phase 1 (S/UWS: P = .001, d = 1.30; TP: P = .019, d = 0.87). In angle comparisons in landing phase 1, no WG/S showed greater mean wrist extension angles compared with S/UWS (P = .046; d = 0.80), but no significant differences with TP (P = .096; d = 0.65). Also, in landing phase 1, total ROM arc of the right wrist was greater in the no-WG/S condition compared with S/UWS (P = .018; d = 0.88), but there were no differences with TP (P = .400; d = 0.52).

CONCLUSION

These data show an increased wrist flexion moment using S/UWS and TP compared with the no-WG/S condition in landing phase 1 of back handsprings. Also, increased wrist extension angles and total arc ROM of the right wrist were found in the no-WG/S condition compared with S/UWS, but not with TP in landing phase 1. S/UWS may be helpful to reduce wrist joint angles, specifically wrist extension in landing phase 1, but both S/UWS and TP caused higher wrist flexion joint moment in landing phase 1. There were no differences found in GFG among the three variables.

CLINICAL RELEVANCE

In the first half of the back handspring, wrist guards can limit wrist extension joint angles and total arc ROM; however, an increased wrist flexion moment was found when wrist guards were worn, which may potentially lead to an increased risk of injury. Injury history, especially overuse signs/symptoms, and previous surgery on the wrist joint need to be well considered before the application or use of wrist guards. Also, the amount of time/exposure wearing wrist guards should be carefully controlled in young female gymnasts.

Outcomes of Adolescent T-condylar Fractures: Kids Do Not Always Make You Look Good

BACKGROUND

Optimal treatment for pediatric and adolescent T-condylar fractures remains poorly understood. We sought to assess how functional outcomes and range of motion (ROM) after surgical fixation of T-condylar fractures are affected by patient and surgical factors.

METHODS

This is a retrospective cohort study of 52 patients with operatively treated T-condylar fractures at a single tertiary pediatric referral center between 2003 and 2021. All patients younger than 18 at the time of injury with a radiographically confirmed diagnosis were included.

RESULTS

Fifty-two T-condylar fractures were included, with a mean patient age of 12.9 years (SD, 2.8). The cohort was 65% male. Nine (19%) fractures were open, 46% (24/52) were AO type C2, and 33% (17/52) occurred in skeletally mature individuals. The surgical approach was through olecranon osteotomy in 29% (15/52) of patients, and fixation included anatomically specific plates and screws in 42% (22/52) of patients. In our cohort, 46% (24/52) achieved good outcomes based on Jarvis ROM criteria and 42% (22/52) achieved good to excellent results based on Roberts functional criteria. The median loss of ROM was 58 degrees at 6 weeks, 20 degrees at 3 and 6 months, and 8 degrees at 1 year postoperatively. We observed a complication rate of 54% (28/52). Patients undergoing adult-type plate fixation had better postoperative range of motion at 6 weeks (ROM loss 52 vs. 80 degrees, P =0.03) and 3 months (10 vs. 35 degrees P =0.004) compared with pediatric-type fixation and trended towards better functional outcomes. We did not identify significant differences in functional outcome scores or complication rates with respect to surgical approach or skeletal maturity.

CONCLUSIONS

Surgical fixation of pediatric and adolescent T-condylar fractures achieved a good to excellent functional outcome in only a minority of patients (46% Jarvis / 42% Roberts) with a high rate of postoperative complications (54%). Future work is needed to elucidate optimal treatment to minimize complications and achieve the best functional outcomes in these challenging fractures.

LEVEL OF EVIDENCE

Level-IV.

Blood-based diagnosis and risk stratification of patients with pancreatic intraductal papillary mucinous neoplasm (IPMN)

PURPOSE

Intraductal papillary mucinous neoplasm (IPMN) is a precursor of pancreatic ductal adenocarcinoma. Low-grade dysplasia has a relatively good prognosis, whereas high-grade dysplasia and IPMN invasive carcinoma require surgical intervention. However, diagnostic distinction is difficult. We aimed to identify biomarkers in peripheral blood for accurate discrimination.

EXPERIMENTAL DESIGN

Sera were obtained from 302 patients with IPMNs and 88 healthy donors. For protein biomarkers, serum samples were analyzed on microarrays made of 2,977 antibodies. A support vector machine (SVM) algorithm was applied to define classifiers, which were validated on a separate sample set. For microRNA biomarkers, a PCR-based screen was performed for discovery. Biomarker candidates confirmed by quantitative PCR were used to train SVM classifiers, followed by validation in a different sample set. Finally, a combined SVM classifier was established entirely independent of the earlier analyses, again using different samples for training and validation.

RESULTS

Panels of 26 proteins or seven microRNAs could distinguish high- and low-risk IPMN with an area under the curve (AUC) value of 95% and 94%, respectively. Upon combination, a panel of five proteins and three miRNAs yielded an AUC of 97%. These values were much better than those obtained in the same patient cohort by using the guideline criteria for discrimination. In addition, accurate discrimination was achieved between other patient subgroups.

CONCLUSIONS

Protein and microRNA biomarkers in blood allow precise diagnosis and risk stratification of IPMN cases, which should improve patient management and thus the prognosis of IPMN patients.

Extensor Retinaculum Reconstruction of the Distal Radioulnar Joint in Adolescents

BACKGROUND

This study characterizes the outcomes and complications of surgical reconstruction of distal radioulnar joint (DRUJ) instability using the extensor retinaculum (Herbert sling). Our hypothesis was that extensor retinaculum reconstruction is a reliable method of DRUJ stabilization in adolescents.

METHODS

This was a retrospective study of pediatric patients treated surgically using the Herbert sling for DRUJ instability at a single institution. We identified 22 subjects who underwent surgery at an average of 16.2 years of age (range, 12-18 years). Medical records and available imaging were reviewed for all subjects, and patients were contacted to participate in the prospective completion of the Quick Disabilities of the Arm, Shoulder, and Hand (QuickDASH) questionnaire.

RESULTS

Preoperative symptoms were more commonly pain (95%) than feelings of DRUJ instability (45%), although 100% had instability on physical examination. Eight (36%) patients demonstrated limited supination preoperatively. Twenty-one subjects (95%) noted prior injury to that wrist, 15 of which were distal radius fractures. Surgery consisted of stabilization of the DRUJ using extensor retinaculum, in concert with other procedures to address all potential causes of wrist pain. Postoperatively, DRUJ stability was maintained in 21 of 22 subjects. Of the 12 patients who provided functional outcome scores, median QuickDASH score was 7.6 (range, 0-45).

CONCLUSIONS

Distal radioulnar joint instability in adolescents is often preceded by fracture of the distal radius. Surgeons must maintain a high level of suspicion to appropriately diagnose DRUJ instability, which is often not an isolated pathoanatomical problem. The Herbert sling technique using extensor retinaculum can successfully confer DRUJ stability in this population.

Use of Autoreactive Antibodies in Blood of Patients with Pancreatic Intraductal Papillary Mucinous Neoplasms (IPMN) for Grade Distinction and Detection of Malignancy

(1) Background: A reliable non-invasive distinction between low- and high-risk pancreatic intraductal papillary mucinous neoplasms (IPMN) is needed to effectively detect IPMN with malignant potential. This would improve preventative care and reduce the risk of developing pancreatic cancer and overtreatment. The present study aimed at exploring the presence of autoreactive antibodies in the blood of patients with IPMN of various grades of dysplasia. (2) Methods: A single-center cohort was studied composed of 378 serum samples from patients with low-grade IPMN (n = 91), high-grade IPMN (n = 66), IPMN with associated invasive cancer (n = 30), pancreatic ductal adenocarcinoma (PDAC) stages T1 (n = 24) and T2 (n = 113), and healthy controls (n = 54). A 249 full-length recombinant human protein microarray was used for profiling the serum samples. (3) Results: 14 proteins were identified as potential biomarkers for grade distinction in IPMN, yielding high specificity but mediocre sensitivity. (4) Conclusions: The identified autoantibodies are potential biomarkers that may assist in the detection of malignancy in IPMN patients.

Sociodemographic Missed-care Predictors for Pediatric Orthopaedic Telemedicine During COVID-19

BACKGROUND

Increased telehealth services may not benefit communities already lacking access to care. Race, socioeconomic status, and insurance type are known to predict missed-care opportunities (MCO) in health care. We examined differences in pediatric orthopaedic telemedicine MCOs during the COVID-19 pandemic, compared with MCOs of in-person visits in a prepandemic time frame. We hypothesized that groups with known health disparities would experience higher rates of pediatric orthopedic telemedicine MCOs.

METHODS

We retrospectively analyzed pediatric orthopaedic telemedicine MCOs during the COVID-19 pandemic lockdown (March-May 2020) and in-person pediatric orthopaedic visit MCOs during a nonpandemic timeframe (March-May 2019). We examined predictors of MCOs including race, ethnicity, language, insurance status, and other socioeconomic determinants of health.

RESULTS

There were 1448 telemedicine appointments in the pandemic cohort and 8053 in-person appointments in the prepandemic cohort. Rates of telemedicine MCOs (12.5%; n=181) were significantly lower than in-person MCOs (19.5%; n=1566; P<0.001). Telemedicine appointments with public insurance or without insurance (P<0.001) and being Black or Hispanic/Latinx (P=0.003) were associated with MCOs. There were significant differences between in-person MCOs and telemedicine MCOs among all predictors studied, except for orthopaedic subspecialty team and patient's social vulnerability index.

CONCLUSIONS

Patients with telemedicine appointments during the COVID-19 pandemic were less likely to experience MCOs than patients with in-person visits during the nonpandemic timeframe. However, when controlling for socioeconomic factors including race, ethnicity, and insurance type, disparities found for in-person visits persisted with the shift to telemedicine. Pediatric orthopaedists should be aware that the use of telemedicine does not necessarily improve access for our most vulnerable patients.

LEVEL OF EVIDENCE

Level III.

Glass Ceiling in Hand Surgery: Publication Trends by Gender

BACKGROUND

Women are frequently underrepresented across surgical subspecialties and may face barriers to academic advancement. Abstracts presented at American Society for Surgery of the Hand annual meeting (ASSH-AM) highlight some of the top research in hand surgery. We sought to explore differences in abstract characteristics and publication rates based on senior author gender.Though there have been increasing efforts at inclusivity in orthopedic and plastic surgery, women face several barriers to entering the field, publish less frequently, and are underrepresented in leadership positions. Understanding the stages at which discrepancies in research productivity exist may help to address these challenges.

METHODS

Abstracts from the 2010-2017 ASSH-AMs were reviewed to determine basic characteristics. Author gender was determined through both a search of institutional websites for gender-specific pronouns and inference of gender based on first name. Subsequent full manuscript publications corresponding to the abstracts were identified through a systematic search of PubMed and Google Scholar.

RESULTS

A total of 560/620 (90.3%) abstracts from 2010-2017 had an identifiable senior author gender (14.5% female). No differences were noted between male- and female-authored abstracts regarding study design including sample size or level of evidence. Female senior authors were more likely than males to author abstracts focused on pediatrics (19.8% vs 9.4%, p=0.01) and were more likely to collaborate with female first authors (41.3% vs 20.0%, p<0.01). Abstract publication rates were lower for female senior authors versus male senior authors (61.7% vs 74.5%, p=0.02).

CONCLUSION

The number of abstracts with female senior authors had similar representation to the membership proportion of women in the ASSH. There were few differences in abstract characteristics based on senior author gender, though senior authors tend to collaborate with investigators of the same gender. Abstracts authored by females were published 13% less frequently overall, meriting further exploration. Level of Evidence: III.

Donor-Site Morbidity for Iliac Crest Harvesting for Pediatric Scaphoid Nonunion

PURPOSE

Screw fixation with iliac crest bone grafting (ICBG) is a well-studied treatment for pediatric scaphoid nonunions. Studies in adults, as well as in pediatric spine fusions, have demonstrated high rates of complications with ICBG, including longer-term donor site pain. We hypothesized that in pediatric patients undergoing ICBG for scaphoid nonunion, the donor site complication rate would be lower than that reported in other populations.

METHODS

Records of patients ages 0-18 years at a single institution undergoing surgical reconstruction for scaphoid nonunion from 1995 to 2016 were reviewed. Patient and surgical variables were recorded, including how ICBG was harvested. Donor site complications were recorded, including donor site pain beyond 30 days after surgery, infection, peri-incisional or lower extremity numbness at any point after surgery and reoperation at the donor site at any time point after surgery.

RESULTS

During the study period, 119 wrists in 117 patients underwent internal fixation and ICBG for scaphoid nonunion. The average age was 16 years; mean follow-up was 1 year. The majority of wrists (73, 62.9%) underwent harvest of both outer and inner tables of the iliac crest; 38 (31.9%) had only outer table harvested; 5 (4.3%) had only cancellous graft harvested. Ten wrists (8.4%) had a donor site complication. The most common donor site complication was donor site pain beyond 30 days after surgery (5, 4.2%), followed by numbness (4, 3.4%). No infections, seromas, or reoperations at the donor site occurred. In comparison to those subjects who did not experience complications, we found no difference based on the age at surgery or the type of graft used. Female patients were more likely to have a recorded complication than males.

CONCLUSIONS

Donor site morbidity for iliac crest grafting in pediatric patients undergoing scaphoid nonunion surgery appears to be lower than that previously reported in adult patients.

TYPE OF STUDY/LEVEL OF EVIDENCE

Therapeutic IV.

Variation Among Surgeons Regarding the Use of Preoperative Antibiotics in Percutaneous Pinning Procedures of the Upper Extremity in the Pediatric Population

Background: Preoperative antibiotics may not be necessary, given the very low infection rates associated with percutaneous pinning (PP) procedures of the upper extremity (UE). The purpose of this study was to determine the patterns and variation surrounding the use of preoperative antibiotics when performing PP procedures of the child's UE. Methods: A survey was sent to all members of Pediatric Orthopedic Society of North America to assess the use and opinions regarding preoperative antibiotics for PP procedures of the UE. Queries included the surgeon's current practice and thoughts regarding the need for preoperative antibiotics based on the anatomical location of the procedure. Results: Eight-one percent of the 295 respondents routinely order preoperative antibiotics for all PP procedures of the UE; however, only 60% felt that all patients must receive preoperative antibiotics. The requirement for preoperative antibiotics varied based on the anatomical location-81% for shoulder, 70% for elbow, 66% for wrist, and 62% for hand/finger. Canadian surgeons were significantly less likely to believe that preoperative antibiotics must be used in all UE cases, all shoulder cases, and all elbow cases (all Ps = .04). Conclusion: The vast majority (81%) of surgeons surveyed routinely prescribe antibiotics for PP procedures of the UE despite the fact that 40% of surgeons felt that antibiotics were not necessary for all procedures. As the PP procedure is performed more distally on the UE, fewer surgeons feel preoperative antibiotics are necessary. Future studies assessing infection rates with and without the use of preoperative antibiotics are necessary to determine the true need for these medications.

Closed Reduction and Immobilization of Pediatric Fifth Metacarpal Neck Fractures

BACKGROUND

There is no clear consensus for the criteria for closed treatment of metacarpal neck fractures. Our objective was to determine whether closed reduction of pediatric fifth metacarpal neck fractures results in a clinically meaningful improvement in radiographic angulation.

METHODS

We performed a retrospective cohort study of pediatric patients with fifth metacarpal neck fractures treated with closed reduction. Radiographs were examined for sagittal fracture angulation measured post-reduction, 2 to 14 days post-reduction, and 21 to 35 days post-reduction. We compared the angulation for open versus closed physes, initial fracture angulation greater than or less than 50°, and immobilization in extension versus intrinsic-plus position.

RESULTS

Fifty-four subjects were included with an average age of 14.8 years at the time of injury and a mean initial fracture angulation of 42.7°. The improvement in fracture angulation was 8.3° (90% confidence interval [CI], 5.9-10.7) on post-reduction radiographs, 8.5° (90% CI, 6.1-10.9) at 2 to 14 days post-reduction, and 4.3° (90% CI, 1.4-7.2) at 21 to 35 days post-reduction. Subgroup analysis showed that patients with injury angle greater than or equal to 50° had significantly higher mean reductions than those with injury angle less than 50°. In this group, angulation improved 15.6° (90% CI, 8.5-22.7) post-reduction, 15.1° (90% CI, 10.1-20.1) at 2 to 14 days post-reduction, and 16.5° (90% CI, 10.4-22.6) at 21 to 35 days post-reduction.

CONCLUSIONS

Closed reduction of pediatric fifth metacarpal neck fractures with initial fracture angulation less than 50° may not meaningfully improve sagittal alignment. For fractures with initial angulation greater than or equal to 50°, closed reduction resulted in clinically important, statistically significant, and lasting improvements of 16.5°.

How Risky Are Risk Factors? An Analysis of Prenatal Risk Factors in Patients Participating in the Congenital Upper Limb Differences Registry

Purpose

Risk factors for congenital upper limb differences (CoULDs) are often studied at the general population level. The CoULD registry provides a unique opportunity to study prenatal risk factors within a large patient sample.

Methods

All patients enrolled between June 2014 and March 2020 in the prospective CoULD registry, a national multicenter database of patients diagnosed with a CoULD, were included in the analysis. We analyzed self-reported, prenatal risk factors, including maternal smoking, alcohol use, recreational drug use, prescription drug use, gestational diabetes mellitus (GDM), and gestational hypertension. The outcome measures included comorbid medical conditions, proximal involvement of limb difference, bilateral involvement, and additional orthopedic conditions. Multivariable logistic regression was used to analyze the effect of the risk factors, controlling for sex and the presence of a named syndrome.

Results

In total, 2,410 patients were analyzed, of whom 72% (1,734) did not have a self-reported risk factor. Among the 29% (676) who did have at least 1 risk factor, prenatal maternal prescription drug use was the most frequent (376/2,410; 16%). Maternal prescription drug use was associated with increased odds of patient medical comorbidities (odds ratio [OR] = 1.43, P = .02). Gestational diabetes mellitus was associated with increased odds of comorbid medical conditions (OR = 1.58, P = .04), additional orthopedic conditions (OR = 1.51, P = .04), and proximal involvement (OR = 1.52, P = .04). Overall, reporting 1 or more risk factors increased the odds of patient comorbid medical conditions (OR = 1.42, P < .001) and additional orthopedic conditions (OR = 1.25, P = .03).

Conclusions

Most caregivers (72%) did not report a risk factor during enrollment. However, reporting a risk factor was associated with patient medical and orthopedic comorbidities. Of note, GDM alone significantly increased the odds of both these outcome measures along with proximal limb differences. These findings highlight the ill-defined etiology of CoULDs but suggest that prenatal risk factors, especially GDM, are associated with a higher degree of morbidity.

Type of study/level of evidence

Prognostic III.

Anxiety surrounding supracondylar humerus pin removal in children

PURPOSE

The purpose of this study was to quantify the anxiety experienced by patients undergoing pin removal in clinic following closed reduction and percutaneous pinning for supracondylar humerus fractures.

METHODS

We prospectively enrolled 53 patients (3-8 years) treated for supracondylar humerus fracture with closed reduction and percutaneous pinning between July 2018 and February 2020. Demographic and injury data were recorded. Heart rate and the Face, Legs, Activity, Cry, and Consolability scale were measured immediately before pin removal and after pin removal, and crossover control values were obtained at the subsequent follow-up clinic visit.

RESULTS

All patients experienced anxiety immediately prior to pin removal (95% confidence interval, 94%-100%) with a median Face, Legs, Activity, Cry, and Consolability score of 7 (interquartile range, 6-8). In addition, 98% of subjects experienced an elevated heart rate (95% confidence interval, 88%-100%). Patients experienced a median 73% reduction in Face, Legs, Activity, Cry, and Consolability score and mean 21% reduction in heart rate from prior to pin removal to after pin removal (p < 0.001). All 45 patients who completed their follow-up visit had a control Face, Legs, Activity, Cry, and Consolability score of 0 and a mean control heart rate of 89.7 bpm. Twenty-five of these 45 subjects (56%) had an elevated control heart rate for their age and sex. Mean heart rate prior to pin removal was 36% higher than control heart rate. There were no sex differences detected in Face, Legs, Activity, Cry, and Consolability scores or heart rate.

CONCLUSIONS

Pediatric patients experience high levels of anxiety when undergoing pin removal following closed reduction and percutaneous pinning for supracondylar humerus fractures. This is an area of clinical practice where intervention may be warranted to decrease patient anxiety.

LEVEL OF EVIDENCE

II.

The Efficacy of Nonsurgical and Surgical Interventions in the Treatment of Pediatric Wrist Ganglion Cysts

PURPOSE

The treatment of ganglion cysts of the wrist remains understudied in the pediatric population, with the literature showing variable recurrence rates following different interventions. This study sought to determine whether surgical and nonsurgical management of pediatric ganglion cysts was associated with improved resolution rates when compared to observation alone.

METHODS

We identified 654 cases of pediatric ganglion cysts treated across 5 institutions between 2012 and 2017. The mean age at presentation was 11.6 ± 5.2 years. Of the patients, 315 had >2 years (mean, 50.0 months) of follow-up, either via chart review or telephone callbacks. There were 4 different treatment groups: (1) observation, (2) cyst aspiration, (3) removable orthosis, and (4) surgical excision.

RESULTS

For patients followed >2 years, the cyst resolved in 44% (72/163) of those observed. Only 18% (9/49) of those treated with aspiration resolved, and 55% (12/22) of those treated with an orthosis resolved. Surgical excision was associated with resolution of the cyst in 73% (59/81) of patients. Observation had higher rates of resolution compared to aspiration. Orthosis fabrication and observation had similar rates of cyst resolution. Surgery had the highest rates of resolution when compared to observation and aspiration. Patients older than 10 years were less likely to have the cyst resolve with observation (35%; 28/80) than those younger than 10 years (53%; 44/83) at >2 years of follow-up.

CONCLUSIONS

This study did not find evidence that nonsurgical treatments were associated with improved rates of cyst resolution compared to observation alone in a large pediatric sample. Surgical excision had the overall highest rate of resolution. Despite the costs and increased clinic time of orthosis fabrication and aspiration, these treatments were not associated with improved rates of cyst resolution in pediatric ganglion cysts compared to observation, with aspiration having higher rates of recurrence compared to observation.

TYPE OF STUDY/LEVEL OF EVIDENCE

Therapeutic IV.

Promoter Hypermethylation Promotes the Binding of Transcription Factor NFATc1, Triggering Oncogenic Gene Activation in Pancreatic Cancer

Studies have indicated that some genes involved in carcinogenesis are highly methylated in their promoter regions but nevertheless strongly transcribed. It has been proposed that transcription factors could bind specifically to methylated promoters and trigger transcription. We looked at this rather comprehensively for pancreatic ductal adenocarcinoma (PDAC) and studied some cases in more detail. Some 2% of regulated genes in PDAC exhibited higher transcription coupled to promoter hypermethylation in comparison to healthy tissue. Screening 661 transcription factors, several were found to bind specifically to methylated promoters, in particular molecules of the NFAT family. One of them-NFATc1-was substantially more strongly expressed in PDAC than control tissue and exhibited a strong oncogenic role. Functional studies combined with computational analyses allowed determining affected genes. A prominent one was gene ALDH1A3, which accelerates PDAC metastasis and correlates with a bad prognosis. Further studies confirmed the direct up-regulation of ALDH1A3 transcription by NFATc1 promoter binding in a methylation-dependent process, providing insights into the oncogenic role of transcription activation in PDAC that is promoted by DNA methylation.

MicroRNAs in blood act as biomarkers of colorectal cancer and indicate potential therapeutic targets

Association studies have linked alterations of blood-derived microRNAs (miRNAs) with colorectal cancer (CRC). Here, we performed a microarray-based comparison of the profiles of 2549 miRNAs in 80 blood samples from healthy donors and patients with colorectal adenomas, colorectal diverticulitis and CRC at different stages. Confirmation by quantitative real-time PCR (RT-PCR) was complemented by validation of identified molecules in another 36 blood samples. No variations in miRNA levels were observed in samples from patients with colorectal adenomas and diverticulitis or from healthy donors. However, there were 179 CRC-associated miRNAs of differential abundance compared to healthy controls. Only three - miR-1225-5p, miR-1207-5p and miR-4459 - exhibited increased levels at all CRC stages. Most deregulated miRNAs (128/179, 71%) specifically predicted metastatic CRC. Pathway analysis found several cancer-related pathways to which the miRNAs contribute in various ways. In conclusion, miRNA levels in blood vary throughout CRC progression and affect cellular functions relevant to haematogenous CRC progression and dissemination. The identified biomarker and therapeutic candidates require further confirmation of their clinical relevance.

Congenital Upper Limb Differences Registry (CoULD): Registry Inclusion Effect

PURPOSE

To advance the understanding of the epidemiology and treatment outcomes of congenital upper limb differences, a multicenter registry for Congenital Upper Limb Differences (CoULD) was established. After 4 years of recruitment, we sought to examine whether the relative frequency of congenital conditions compares with prior cross-sectional research and how the data have matured over time by (1) comparing our registry population with previous studies in similar populations and (2) evaluating the change over time of relative frequencies of selected conditions within the CoULD registry cohort, specifically to investigate for registry inclusion effects.

METHODS

Data from the 2 founding centers in the CoULD registry were analyzed over a 4-year period. We compared patients included in the CoULD registry against 2 prior studies by matching each condition according to the Oberg-Manske-Tonkin classification system. The relative frequency of 4 representative conditions was calculated to evaluate change over time and to determine when the inception cohort effect diminished.

RESULTS

The CoULD cohort of 1,381 patients was found to have notable differences compared with a 1-year cross-sectional cohort from the U.S. Midwest and a Swedish birth registry. Each of these registries had differences from the CoULD population in prevalence for approximately 33% of the diagnosis categories. The CoULD registry identified and included more pathologies of late presentation and those that do not commonly require surgical care. Changes in relative frequencies of incident and prevalent conditions, the registry inclusion effect, occurred early and stabilized by the third year.

CONCLUSIONS

The CoULD registry captures a different relative frequency of conditions than prior studies in similar populations. The findings highlight the CoULD registry may be a more accurate representation of clinical practice in tertiary referral centers; however, it is important to note that there was a registry inclusion effect identified.

CLINICAL RELEVANCE

Inclusion criteria are an important consideration with any longitudinal data collection method and data should display stability prior to registry reporting.

Human Retrotransposons and the Global Shutdown of Homeostatic Innate Immunity by Oncolytic Parvovirus H-1PV in Pancreatic Cancer

Although the oncolytic parvovirus H-1PV has entered clinical trials, predicting therapeutic success remains challenging. We investigated whether the antiviral state in tumor cells determines the parvoviral oncolytic efficacy. The interferon/interferon-stimulated genes (IFN/ISG)-circuit and its major configurator, human endogenous retroviruses (HERVs), were evaluated using qRT-PCR, ELISA, Western blot, and RNA-Seq techniques. In pancreatic cancer cell lines, H-1PV caused a late global shutdown of innate immunity, whereby the concomitant inhibition of HERVs and IFN/ISGs was co-regulatory rather than causative. The growth-inhibitory IC50 doses correlated with the power of suppression but not with absolute ISG levels. Moreover, H-1PV was not sensitive to exogenous IFN despite upregulated antiviral ISGs. Such resistance questioned the biological necessity of the oncotropic ISG-shutdown, which instead might represent a surrogate marker for personalized oncolytic efficacy. The disabled antiviral homeostasis may modify the activity of other viruses, as demonstrated by the reemergence of endogenous AluY-retrotransposons. This way of suppression may compromise the interferogenicity of drugs having gemcitabine-like mechanisms of action. This shortcoming in immunogenic cell death induction is however amendable by immune cells which release IFN in response to H-1PV.

Blood biomarkers for differential diagnosis and early detection of pancreatic cancer

Pancreatic cancer is currently the most lethal tumor entity and case numbers are rising. It will soon be the second most frequent cause of cancer-related death in the Western world. Mortality is close to incidence and patient survival after diagnosis stands at about five months. Blood-based diagnostics could be one crucial factor for improving this dismal situation and is at a stage that could make this possible. Here, we are reviewing the current state of affairs with its problems and promises, looking at various molecule types. Reported results are evaluated in the overall context. Also, we are proposing steps toward clinical utility that should advance the development toward clinical application by improving biomarker quality but also by defining distinct clinical objectives and the respective diagnostic accuracies required to achieve them. Many of the discussed points and conclusions are highly relevant to other solid tumors, too.

Phase I trial of donor-derived modified immune cell infusion in kidney transplantation

BACKGROUNDPreclinical experiments have shown that donor blood cells, modified in vitro by an alkylating agent (modified immune cells [MICs]), induced long-term specific immunosuppression against the allogeneic donor.METHODSIn this phase I trial, patients received either 1.5 × 106 MICs per kg BW on day -2 (n = 3, group A), or 1.5 × 108 MICs per kg BW on day -2 (n = 3, group B) or day -7 (n = 4, group C) before living donor kidney transplantation in addition to post-transplantation immunosuppression. The primary outcome measure was the frequency of adverse events (AEs) until day 30 (study phase) with follow-up out to day 360.RESULTSMIC infusions were extremely well tolerated. During the study phase, 10 treated patients experienced a total of 69 AEs that were unlikely to be related or not related to MIC infusion. No donor-specific human leukocyte antigen Abs or rejection episodes were noted, even though the patients received up to 1.3 × 1010 donor mononuclear cells before transplantation. Group C patients with low immunosuppression during follow-up showed no in vitro reactivity against stimulatory donor blood cells on day 360, whereas reactivity against third-party cells was still preserved. Frequencies of CD19+CD24hiCD38hi transitional B lymphocytes (Bregs) increased from a median of 6% before MIC infusion to 20% on day 180, which was 19- and 68-fold higher, respectively, than in 2 independent cohorts of transplanted controls. The majority of Bregs produced the immunosuppressive cytokine IL-10. MIC-treated patients showed the Immune Tolerance Network operational tolerance signature.CONCLUSIONMIC administration was safe and could be a future tool for the targeted induction of tolerogenic Bregs.TRIAL REGISTRATIONEudraCT number: 2014-002086-30; ClinicalTrials.gov identifier: NCT02560220.FUNDINGFederal Ministry for Economic Affairs and Technology, Berlin, Germany, and TolerogenixX GmbH, Heidelberg, Germany.

A Comparative Analysis of 150 Thumb Polydactyly Cases from the CoULD Registry Using the Wassel-Flatt, Rotterdam, and Chung Classifications

PURPOSE

Three commonly used classifications for thumb polydactyly are the Wassel-Flatt, Rotterdam, and Chung. The ideal classification system would have high validity and reliability and be descriptive of the thumb anomaly. The purposes of this investigation were to (1) compare the inter- and intrarater reliability of these 3 classifications when applied to a large sample of patients enrolled in the Congenital Upper Limb Differences (CoULD) Registry and (2) determine the prevalence of radial polydactyly types when using the various classifications in a North American population.

METHODS

Inter- and intrarater reliability were determined using 150 cases of radial polydactyly presented in a Web-based format to 7 raters in 3 rounds, a preliminary training round and 2 observation rounds. Raters classified each case according to the Wassel-Flatt, Rotterdam, and Chung classifications. Inter- and intrarater reliability were evaluated with the intraclass correlation coefficient (ICC) calculated using 2-way random measures with perfect agreement.

RESULTS

For Wassel-Flatt, both the interrater (ICC, 0.93) and the intrarater reliability (ICC, 0.91) were excellent. The Rotterdam classification had excellent reliability for both interrater reliability (ICC, 0.98) and intrarater reliability (ICC, 0.94), when considering type alone. Interrater analysis of the additional subtypes demonstrated a wide range of reliabilities. The Chung classification had good interrater (ICC, 0.88) and intrarater reliability (ICC, 0.77). Within the Wassel-Flatt classification, the most frequent unclassifiable thumb was a type IV hypoplastic thumb as classified by the Rotterdam classification.

CONCLUSIONS

The Wassel-Flatt and Rotterdam classifications for radial polydactyly have excellent inter- and intrarater reliability. Despite its simplicity, the Chung classification was less reliable in comparison. The Chung and Rotterdam classification systems capture the hypoplastic subtypes that are unclassifiable in the Wassel-Flatt system. Addition of the hypoplastic subtype to the Wassel-Flatt classification (eg, Wassel-Flatt type IVh) would maintain the highest reliability and classify over 90% of thumbs deemed unclassifiable in the Wassel-Flatt system.

CLINICAL RELEVANCE

The Wassel-Flatt and Rotterdam classifications have excellent inter-and intrarater reliability for the hand surgeon treating thumb polydactyly. Addition of a hypoplastic subtype to the Wassel-Flatt (Type 4h) allows classification of most previously unclassifiable thumbs.

Association of Radial Longitudinal Deficiency and Thumb Hypoplasia: An Update Using the CoULD Registry

BACKGROUND

Deficiency of the radial aspect of the forearm and hand is the most common congenital longitudinal deficiency of the upper limb. Radial longitudinal deficiency is associated with several named syndromes. The purpose of the present study was to explore patterns of radial longitudinal deficiency and thumb hypoplasia in syndromes and to examine the severity of these differences across various syndromes.

METHODS

Data were collected from the Congenital Upper Limb Differences (CoULD) registry. Congenital differences are classified in the registry with use of the Oberg-Manske-Tonkin (OMT) classification system. Diagnosis of a syndrome by a physician as noted in the CoULD registry was recorded. Thumb deficiency and radial deficiency were classified according to the modified versions of the Blauth criteria and the Bayne and Klug criteria, respectively.

RESULTS

We identified 259 patients with 383 affected limbs with radial deficiency. Eighty-three of these patients had a diagnosed syndrome. The severity of radial deficiency was correlated with the severity of thumb deficiency. The Kendall tau coefficient indicated significant correlation between radial severity and thumb severity (tau = 0.49 [95% confidence interval = 0.40 to 0.57]; p < 0.05). Subjects with a syndrome were twice as likely to have bilateral deficiency and 2.5 times more likely to have both radial and thumb deficiency compared with subjects without a syndrome. Subjects with VACTERL syndrome (vertebral defects, anal atresia, cardiac anomalies, tracheoesophageal fistula, renal anomalies, and limb defects) had patterns of thumb and radial deficiency similar to the general cohort, whereas subjects with Holt-Oram syndrome, TAR (thrombocytopenia absent radius) syndrome, and Fanconi anemia demonstrated varied presentations of thumb and radial deficiency.

CONCLUSIONS

The present study investigated the characteristics of patients with radial longitudinal deficiency and thumb hypoplasia. Our results support the findings of previous research correlating the severity of radial deficiency with the severity of thumb deficiency. Furthermore, we identified characteristic features of patients with radial longitudinal deficiency and associated syndromes.

Follow-up Study on the Effects of Tendon Transfers and Open Reduction on Moderate Glenohumeral Joint Deformity in Brachial Plexus Birth Injury

BACKGROUND

Soft-tissue contractures about the shoulder in patients with brachial plexus birth injury are common and can lead to progressive shoulder displacement and glenohumeral dysplasia. Open or arthroscopic reduction with musculotendinous lengthening and tendon transfers have become the standard of care. The clinical function and radiographic joint remodeling beyond the first 2 years after surgery are not well understood.

METHODS

We performed a follow-up study of 20 patients with preexisting mild to moderate glenohumeral joint deformity who had undergone open glenohumeral joint reduction with latissimus dorsi and teres major tendon transfers and concomitant musculotendinous lengthening of the pectoralis major and/or subscapularis. Prospective collection of Modified Mallet and Active Movement Scale (AMS) scores and radiographic analysis of cross-sectional imaging for glenoid version, humeral head subluxation, and glenohumeral joint deformity classification were analyzed for changes over time.

RESULTS

The average duration of radiographic follow-up was 4.2 years (range, 2 to 6 years). The mean glenoid version improved from -31.8° to -15.4° (p < 0.0001). The mean percentage of the humeral head anterior to the middle of the glenoid (PHHA) improved from 9.6% to 30.4% (p < 0.0001). The mean glenohumeral joint deformity score improved from 3.7 to 2.1 (p < 0.0001).

CONCLUSIONS

All parameters showed the greatest magnitude of improvement between preoperative measurements and 1 year of follow-up. There were no significant changes beyond the 1-year time point in the Mallet scores, AMS scores, or radiographic outcome measures, possibly because of insufficient power, although trends of improvement were noted for some outcomes. No decline in outcome measures was found during the study period.

LEVEL OF EVIDENCE

Therapeutic Level IV. See Instructions for Authors for a complete description of levels of evidence.

The transcription factor FLI1 promotes cancer progression by affecting cell cycle regulation

Binding of transcription factors to mutated DNA sequences is a likely regulator of cancer progression. Noncoding regulatory mutations such as those on the core promoter of the gene encoding human telomerase reverse transcriptase have been shown to affect gene expression in cancer. Using a protein microarray of 667 transcription factor DNA-binding domains and subsequent functional assays, we looked for transcription factors that preferentially bind the mutant hTERT promoter and characterized their downstream effects. One of them, friend leukemia integration 1 (FLI1), which belongs to the E26 transforming-specific family of transcription factors, exhibited particularly strong effects with respect to regulating hTERT expression, while the even better binding ELK3 did not. Depletion of FLI1 decreased expression of the genes for cyclin D1 (CCND1) and E2F transcription factor 2 (E2F2) resulting in a G1/S cell cycle arrest and in consequence a reduction of cell proliferation. FLI1 also affected CMTM7, another gene involved in G1/S transition, although by another process that suggests a balanced regulation of the tumor suppressor gene's activity via opposing regulation processes. FLI1 expression was found upregulated and correlated with an increase in CCND1 expression in pancreatic cancer and brain tumors. In non-neoplastic lung cells, however, FLI1 depletion led to rapid progression through the cell cycle. This coincides with the fact that FLI1 is downregulated in lung tumors. Taken together, our data indicate a cell cycle regulatory hub involving FLI1, hTERT, CCND1 and E2F2 in a tissue- and context-dependent manner.

Outcomes of Late Microsurgical Nerve Reconstruction for Brachial Plexus Birth Injury

PURPOSE

Microsurgical nerve reconstruction has been advocated between 3 and 9 months of life in select patients with brachial plexus birth injury (BPBI), yet some patients undergo indicated surgery after this time frame. Outcomes in these older patients remain poorly characterized. We analyzed outcomes of nerve reconstruction performed after 9 months of age and hypothesized that (1) Active Movement Scale (AMS) scores improve after surgery, and (2) there are no differences in AMS scores between patients undergoing nerve transfers versus those undergoing nerve grafting.

METHODS

From 2000 to 2014, 750 patients at 6 U.S. centers were prospectively enrolled in a multicenter database. We included patients treated with nerve reconstruction after 9 months of age with minimum 12 months' follow-up. Patients were evaluated using AMS scores. To focus on the results of microsurgery, only outcomes prior to secondary surgery were analyzed. We analyzed baseline variables using bivariate statistics and change in AMS scores over time and across treatment groups using linear mixed models.

RESULTS

We identified 32 patients (63% female) with median follow-up of 29.8 months. Median age at microsurgery was 11.2 months. Twenty-five (78%) had an upper trunk injury. Compared with before surgery, total AMS scores improved modestly at 1 year and 2 or more years follow-up. At 1 year follow-up, AMS scores improved for shoulder function (abduction, external rotation) and elbow flexion. Between-group comparisons found no differences in total AMS scores or AMS subscales between graft and transfer groups at 1 year or 2 or more years after surgery, so we cannot recommend one strategy over the other based on our findings.

CONCLUSIONS

Overall, nerve reconstruction in patients with BPBI after 9 months of age resulted in improved function over time. There was no difference in outcomes between nerve transfer and nerve graft groups and 1 or 2 or more years follow-up.

TYPE OF STUDY/LEVEL OF EVIDENCE

Therapeutic IV.

SST gene hypermethylation acts as a pan-cancer marker for pancreatic ductal adenocarcinoma and multiple other tumors: toward its use for blood-based diagnosis

Aberrant DNA methylation is often involved in carcinogenesis. Our initial goal was to identify DNA methylation biomarkers associated with pancreatic cancer. A genomewide methylation study was performed on DNA from pancreatic ductal adenocarcinoma (PDAC) and endocrine pancreas tumors. Validation of DNA methylation patterns and concomitant alterations in expression of gene candidates was performed on patient samples and pancreatic cancer cell lines. Furthermore, validation was done on independent data from The Cancer Genome Atlas (TCGA) and Gene Expression Omnibus (GEO). Finally, droplet digital PCR was employed to detect DNA methylation marks in cell-free (cf) DNA isolated from plasma samples of PDAC patients and cancer-free blood donors. Hypermethylation of the SST gene (encoding somatostatin) and concomitant downregulation of its expression were discovered in PDAC and endocrine tumor tissues while not being present in chronic pancreatitis (inflamed) tissues and normal pancreas. Fittingly, treatment with a somatostatin agonist (octreotide) reduced cell proliferation and migration of pancreatic cancer cells. Diagnostic performance of SST methylation in a receiver operating characteristic curve analysis was 100% and 89% for tissue and plasma samples, respectively. A large body of TCGA and GEO data confirmed SST hypermethylation and downregulation in PDAC and showed a similar effect in a broad spectrum of other tumor entities. SST promoter methylation represents a sensitive and promising molecular, pan-cancer biomarker detectable in tumor tissue, and liquid biopsy samples.

Thumb Hypoplasia Occurring in Patients With Preaxial Polydactyly

PURPOSE

Thumb polydactyly and thumb hypoplasia are generally regarded as separate clinical entities. However, several case reports indicate that hypoplasia of both the thumb and the radius can occur in patients with thumb polydactyly and improved understanding of the genetics of the developing upper limb may give an embryologic explanation for this occurrence. Our hypothesis was that patients with preaxial polydactyly can have ipsilateral thumb hypoplasia that may not be recognized until after surgical reconstruction of the extra digit.

METHODS

We searched our surgical database for all procedures performed on patients with a diagnosis of preaxial polydactyly between 2002 and 2014. We reviewed the medical record for demographic data, surgical procedures, and follow-up information. In addition, all available radiographs were reviewed. Through this, we identified patients with a diagnosis of ipsilateral thumb hypoplasia, including when in the course of treatment the diagnosis was made, and any related subsequent procedures.

RESULTS

We reviewed 132 patients who underwent reconstruction of thumb polydactyly, 10 of whom were identified as having evidence of ipsilateral thumb hypoplasia, an incidence of 8.2%. The diagnosis of thumb hypoplasia was made before surgery in 3 of the 10 patients. One additional patient was noted to have a duplicate thumb on one side and a hypoplastic thumb on the contralateral side.

CONCLUSIONS

This study supports the hypothesis that children with preaxial polydactyly can have ipsilateral thumb hypoplasia that may not be noted before surgery. In this study group, 8% of patients with preaxial polydactyly had ipsilateral hypoplasia.

TYPE OF STUDY/LEVEL OF EVIDENCE

Prognostic IV.

Reconstruction of the Suprascapular Nerve in Brachial Plexus Birth Injury: A Comparison of Nerve Grafting and Nerve Transfers

BACKGROUND

Shoulder external rotation recovery in brachial plexus birth injury is often limited. Nerve grafting to the suprascapular nerve and transfer of the spinal accessory nerve to the suprascapular nerve are commonly performed to restore shoulder external rotation, but the optimal surgical technique has not been clearly demonstrated. We investigated whether there was a difference between nerve grafting and nerve transfer in terms of shoulder external rotation recovery or secondary shoulder procedures.

METHODS

This is a multicenter, retrospective cohort study of 145 infants with brachial plexus birth injury who underwent reconstruction with nerve grafting to the suprascapular nerve (n = 59) or spinal accessory nerve to suprascapular nerve transfer (n = 86) with a minimum follow-up of 18 months (median, 25.7 months [interquartile range, 22.0, 31.2 months]). The primary outcome was the Active Movement Scale (AMS) score for shoulder external rotation at 18 to 36 months. The secondary outcome was secondary shoulder surgery. Two-sample Wilcoxon and t tests were used to analyze continuous variables, and the Fisher exact test was used to analyze categorical variables. The Kaplan-Meier method was used to estimate the cumulative risk of subsequent shoulder procedures, and the proportional hazards model was used to estimate hazard ratios (HRs).

RESULTS

The grafting and transfer groups were similar in Narakas type, preoperative AMS scores, and shoulder subluxation. The mean postoperative shoulder external rotation AMS scores were 2.70 in the grafting group and 3.21 in the transfer group, with no difference in shoulder external rotation recovery between the groups (difference, 0.51 [95% confidence interval (CI), -0.31 to 1.33]). A greater proportion of the transfer group (24%) achieved an AMS score of >5 for shoulder external rotation compared with the grafting group (5%) (odds ratio, 5.9 [95% CI, 1.3 to 27.4]). Forty percent of the transfer group underwent a secondary shoulder surgical procedure compared with 53% of the grafting group; this was a significantly lower subsequent surgery rate (HR, 0.58 [95% CI, 0.35 to 0.95]).

CONCLUSIONS

Shoulder external rotation recovery in brachial plexus birth injury remains disappointing regardless of surgical technique, with a mean postoperative AMS score of 3, 17% of infants achieving an AMS score of >5, and a high frequency of secondary shoulder procedures in this study. Spinal accessory nerve to suprascapular nerve transfers were associated with a higher proportion of infants achieving functional shoulder external rotation (AMS score of >5) and fewer secondary shoulder procedures.

LEVEL OF EVIDENCE

Therapeutic Level III. See Instructions for Authors for a complete description of levels of evidence.

Reconstruction of the Suprascapular Nerve in Brachial Plexus Birth Injury: A Comparison of Nerve Grafting and Nerve Transfers

BACKGROUND

Shoulder external rotation recovery in brachial plexus birth injury is often limited. Nerve grafting to the suprascapular nerve and transfer of the spinal accessory nerve to the suprascapular nerve are commonly performed to restore shoulder external rotation, but the optimal surgical technique has not been clearly demonstrated. We investigated whether there was a difference between nerve grafting and nerve transfer in terms of shoulder external rotation recovery or secondary shoulder procedures.

METHODS

This is a multicenter, retrospective cohort study of 145 infants with brachial plexus birth injury who underwent reconstruction with nerve grafting to the suprascapular nerve (n = 59) or spinal accessory nerve to suprascapular nerve transfer (n = 86) with a minimum follow-up of 18 months (median, 25.7 months [interquartile range, 22.0, 31.2 months]). The primary outcome was the Active Movement Scale (AMS) score for shoulder external rotation at 18 to 36 months. The secondary outcome was secondary shoulder surgery. Two-sample Wilcoxon and t tests were used to analyze continuous variables, and the Fisher exact test was used to analyze categorical variables. The Kaplan-Meier method was used to estimate the cumulative risk of subsequent shoulder procedures, and the proportional hazards model was used to estimate hazard ratios (HRs).

RESULTS

The grafting and transfer groups were similar in Narakas type, preoperative AMS scores, and shoulder subluxation. The mean postoperative shoulder external rotation AMS scores were 2.70 in the grafting group and 3.21 in the transfer group, with no difference in shoulder external rotation recovery between the groups (difference, 0.51 [95% confidence interval (CI), -0.31 to 1.33]). A greater proportion of the transfer group (24%) achieved an AMS score of >5 for shoulder external rotation compared with the grafting group (5%) (odds ratio, 5.9 [95% CI, 1.3 to 27.4]). Forty percent of the transfer group underwent a secondary shoulder surgical procedure compared with 53% of the grafting group; this was a significantly lower subsequent surgery rate (HR, 0.58 [95% CI, 0.35 to 0.95]).

CONCLUSIONS

Shoulder external rotation recovery in brachial plexus birth injury remains disappointing regardless of surgical technique, with a mean postoperative AMS score of 3, 17% of infants achieving an AMS score of >5, and a high frequency of secondary shoulder procedures in this study. Spinal accessory nerve to suprascapular nerve transfers were associated with a higher proportion of infants achieving functional shoulder external rotation (AMS score of >5) and fewer secondary shoulder procedures.

LEVEL OF EVIDENCE

Therapeutic Level III. See Instructions for Authors for a complete description of levels of evidence.

Microsurgery for Brachial Plexus Injury Before Versus After 6 Months of Age: Results of the Multicenter Treatment and Outcomes of Brachial Plexus Injury (TOBI) Study

BACKGROUND

Infants with more severe brachial plexus birth injury (BPBI) benefit from primary nerve surgery to improve function. The timing of the surgery, however, is controversial. The Treatment and Outcomes of Brachial Plexus Injury (TOBI) study is a multicenter prospective study with the primary aim of determining the optimal timing of this surgical intervention. This study compared outcomes evaluated 18 to 36 months after "early" microsurgery (at <6 months of age) with the outcomes of "late" microsurgery (at >6 months of age).

METHODS

Of 216 patients who had undergone microsurgery, 118 were eligible for inclusion because they had had a nerve graft and/or transfer followed by at least 1 physical examination during the 18 to 36-month interval after the microsurgery but before any secondary surgery. Patients were grouped according to whether the surgery had been performed before or after 6 months of age. Postoperative outcomes were measured using the total Active Movement Scale (AMS) score as well as the change in the AMS score. To address hand reinnervation, we calculated a hand function subscore from the AMS hand items and repeated the analysis only for the subjects with a Narakas grade of 3 or 4. Our hypothesis was that microsurgery done before 6 months of age would lead to better clinical outcomes than microsurgery performed after 6 months of age.

RESULTS

Eighty subjects (68%) had early surgery (at a mean age of 4.2 months), and 38 (32%) had late surgery (at a mean age of 10.7 months and a maximum age of 22.0 months). Infants who underwent early surgery presented earlier in life, had more severe injuries at baseline, and had a significantly lower postoperative AMS scores in the unadjusted analysis. However, when we controlled for the severity of the injury, the difference in the AMS scores between the early and late surgery groups was not significant. Similarly, when we restricted our multivariable analysis to patients with a Narakas grade-3 or 4 injury, there was no significant difference in the postoperative AMS hand subscore between the early and late groups.

CONCLUSIONS

This study suggests that surgery earlier in infancy (at a mean age of 4.2 months) does not lead to better postoperative outcomes of BPBI nerve surgery than when the surgery is performed later in infancy (mean age of 10.7 months).

LEVEL OF EVIDENCE

Prognostic Level II. See Instructions for Authors for a complete description of levels of evidence.

Congenital pseudarthrosis of the clavicle: surgical decision making and outcomes

BACKGROUND

Congenital pseudarthrosis of the clavicle (CPC) is a rare entity in which the primary ossification center of the clavicle fails to coalesce. The natural history of CPC is unknown, and there is controversy regarding surgical vs. conservative treatment.

METHODS

A retrospective review of 47 pediatric patients treated for CPC was performed. The Quick Disabilities of the Arm and Shoulder (QuickDASH) survey and the Patient Reported Outcomes Measurement Information System (PROMIS) upper extremity domain were used to assess overall patient satisfaction, function, and quality of life after treatment.

RESULTS

Twenty-four of 47 (51%) patients underwent surgical treatment. Of these, 9 patients (38%, 9/24) underwent surgery at <18 months of age using suture fixation alone, whereas the older 15 surgical patients (15/24, 62%) were treated with plate fixation. The younger surgical cohort had a nonunion rate of 43% (3/7) compared with 13% (2/15) in the older cohort. All surgical patients had resolution of preoperative symptoms. Eleven (11/24, 46%) surgical subjects responded to the follow-up survey. Upper extremity function normalized according to the QuickDASH survey (score of 0 for all subjects). The median PROMIS upper extremity domain score was 55, which was also in the normal range.

CONCLUSIONS

This series of CPC patients improves our understanding of treatment options and outcomes of surgical treatment. All surgical patients had resolution of preoperative symptoms. Patients treated surgically with stable fixation at an older age had higher rates of union than those treated in infancy with suture fixation. Patient-reported outcomes were favorable overall.

NHC-gold compounds mediate immune suppression through induction of AHR-TGFβ1 signalling in vitro and in scurfy mice

Gold compounds have a long history of use as immunosuppressants, but their precise mechanism of action is not completely understood. Using our recently developed liver-on-a-chip platform we now show that gold compounds containing planar N-heterocyclic carbene (NHC) ligands are potent ligands for the aryl hydrocarbon receptor (AHR). Further studies showed that the lead compound (MC3) activates TGFβ1 signaling and suppresses CD4+ T-cell activation in vitro, in human and mouse T cells. Conversely, genetic knockdown or chemical inhibition of AHR activity or of TGFβ1-SMAD-mediated signaling offsets the MC3-mediated immunosuppression. In scurfy mice, a mouse model of human immunodysregulation polyendocrinopathy enteropathy X-linked syndrome, MC3 treatment reduced autoimmune phenotypes and extended lifespan from 24 to 58 days. Our findings suggest that the immunosuppressive activity of gold compounds can be improved by introducing planar NHC ligands to activate the AHR-associated immunosuppressive pathway, thus expanding their potential clinical application for autoimmune diseases.

Incarcerated Medial Epicondyle Fractures With Elbow Dislocation: Risk Factors Associated With Morbidity

BACKGROUND

Incarcerated medial epicondyle fractures in association with elbow trauma are rare and an absolute indication for intervention. Because of the infrequent nature, outcomes following this injury are not well documented. We studied a large cohort of these injuries to determine factors associated with functional outcomes. It was hypothesized that a greater duration between initial presentation and time of surgery would lead to poorer outcomes.

METHODS

A total of 32 patients aged 18 and under who underwent surgical treatment for an incarcerated medical epicondyle fracture at a level-1 pediatric trauma center from 2003 to 2015 were identified. All patients had a confirmed diagnosis of an incarcerated medial epicondyle at surgery. Medical records and radiographs were reviewed to determine the patient demographics, mechanism of injury, preoperative neurological symptoms, time of primary presentation, time of elbow reduction, and time to surgical intervention. Postoperative outcomes, including pain, range of motion, and ulnar nerve symptoms, were also collected. The Roberts outcome score was determined for each subject.

RESULTS

A radiographically confirmed elbow dislocation was identified in 25 subjects. The mean age at injury was 13.2 years (range, 7.3 to 17.8 y). Initial presentation was at a referring institution in 30 patients (94%). First closed reduction attempt of the ulnohumeral joint occurred in the emergency room in 24 subjects (75%); of these 7 subjects (22%) had a first reduction attempted in the emergency room at our institution, 2 patients experienced first elbow reduction during surgical intervention. The median time from first presentation to surgery was 21.9 hours (interquartile range, 15 to 40). Fourteen subjects displayed preoperative ulnar nerve symptoms. Of these, 9 subsequently reported postoperative ulnar nerve symptoms. There was no effect of time to surgical intervention on the Roberts outcome scores at follow-up, nerve symptoms, symptomatic hardware, or need for second surgery to remove hardware. There were 16 subjects with excellent outcomes, 13 with good outcomes, 3 with fair outcomes, and 0 with poor outcomes (based on the Roberts criteria).

CONCLUSIONS

Incarcerated medial epicondyle fractures are commonly associated with ulnar nerve symptoms; however, they are not associated with a significant rate of other complications. There was no increased risk of complications in subjects who had a longer duration between initial presentation and surgery. This suggests that, while the presence of an incarcerated medial epicondyle fracture is certainly an indication for timely operative intervention; the injury in isolation does not need to be considered emergent. Other factors including neurovascular status and ability to achieve joint reduction may still necessitate emergency operative care.

LEVEL OF EVIDENCE

Level IV-therapeutic study, case series.

The Anterior Approach for Transfer of Radial Nerve Triceps Fascicles to the Axillary Nerve

Nerve transfers are an increasingly popular method for surgical treatment of nerve injuries. One of the most popular of these is the transfer of radial nerve triceps fascicles to the axillary nerve. The most common approach for this transfer is the posterior approach, which gives excellent access to both nerves but is not easy to combine with other nerve transfers. We describe here an alternative, the anterior approach, that offers safe access to both radial and axillary nerves and has the added advantage of compatibility with approaches for other common nerve transfers.

In situ, Cell-free Protein Expression on Microarrays and Their Use for the Detection of Immune Responses

Until recently, whole-proteome microarrays for comprehensive studies of protein interactions were mostly produced by individual cloning and cellular expression of very many open reading frames, followed by protein isolation and purification as well as array production. To overcome this cumbersome process, we have developed a method to generate microarrays representing entire proteomes by a combination of multiple spotting and on-chip, cell-free protein expression. Here, we describe the protocol for the production of bacterial protein microarrays. With slight adaptations, however, the procedure can be applied to the proteome of any organism. Expression constructs of each gene are generated by PCR on bacterial genomic DNA followed by a common secondary amplification that is adding relevant regulative elements to either end of the constructs. The unpurified PCR-products are spotted onto the microarray surface. Full-length proteins are directly expressed in situ in a cell-free manner and stay attached to the surface without further action. As an example of a typical application, we describe here the proteome-wide analysis of the immune response to a bacterial infectious agent by characterizing the binding profiles of the antibodies in patient sera.

Early Predictors of Microsurgical Reconstruction in Brachial Plexus Birth Palsy

BACKGROUND

Microsurgical reconstruction is indicated for infants with brachial plexus birth palsy (BPBP) that demonstrate limited spontaneous neurological recovery. This investigation defines the demographic, perinatal, and physical examination characteristics leading to microsurgical reconstruction.

METHODS

Infants enrolled in a prospective multicenter investigation of BPBP were evaluated. Microsurgery was performed at the discretion of the treating provider/center. Inclusion required enrollment prior to six months of age and follow-up evaluation beyond twelve months of age. Demographic, perinatal, and examination characteristics were investigated as possible predictors of microsurgical reconstruction. Toronto Test scores and Hospital for Sick Children Active Movement Scale (AMS) scores were used if obtained prior to three months of age. Univariate and multivariate logistic regression analyses were performed.

RESULTS

365 patients from six regional medical centers met the inclusion criteria. 127 of 365 (35%) underwent microsurgery at a median age of 5.4 months, with microsurgery rates and timing varying significantly by site. Univariate analysis demonstrated that several factors were associated with microsurgery including race, gestational diabetes, neonatal asphyxia, neonatal intensive care unit admission, Horner's syndrome, Toronto Test score, and AMS scores for finger/thumb/wrist flexion, finger/thumb extension, wrist extension, elbow flexion, and elbow extension. In multivariate analysis, four factors independently predicted microsurgical intervention including Horner's syndrome, mean AMS score for finger/thumb/ wrist flexion <4.5, AMS score for wrist extension <4.5, and AMS score for elbow flexion <4.5. In this cohort, microsurgical rates increased as the number of these four factors present increased from zero to four: 0/4 factors = 0%, 1/4 factors = 22%, 2/4 factors = 43%, 3/4 factors = 76%, and 4/4 factors = 93%.

CONCLUSIONS

In patients with BPBP, early physical examination findings independently predict microsurgical intervention. These factors can be used to provide counseling in early infancy for families regarding injury severity and plan for potential microsurgical intervention.Level of Evidence: Prognostic Level I.

Transcriptional variations in the wider peritumoral tissue environment of pancreatic cancer

Transcriptional profiling was performed on 452 RNA preparations isolated from various types of pancreatic tissue from tumour patients and healthy donors, with a particular focus on peritumoral samples. Pancreatic ductal adenocarcinomas (PDAC) and cystic tumours were most different in these non-tumorous tissues surrounding them, whereas the actual tumours exhibited rather similar transcript patterns. The environment of cystic tumours was transcriptionally nearly identical to normal pancreas tissue. In contrast, the tissue around PDAC behaved a lot like the tumour, indicating some kind of field defect, while showing far less molecular resemblance to both chronic pancreatitis and healthy tissue. This suggests that the major pathogenic difference between cystic and ductal tumours may be due to their cellular environment rather than the few variations between the tumours. Lack of correlation between DNA methylation and transcript levels makes it unlikely that the observed field defect in the peritumoral tissue of PDAC is controlled to a large extent by such epigenetic regulation. Functionally, a strikingly large number of autophagy-related transcripts was changed in both PDAC and its peritumoral tissue, but not in other pancreatic tumours. A transcription signature of 15 autophagy-related genes was established that permits a prognosis of survival with high accuracy and indicates the role of autophagy in tumour biology.

Endogenous CHRNA7-ligand SLURP1 as a potential tumor suppressor and anti-nicotinic factor in pancreatic cancer

Smoking is associated with increased risk and poorer prognosis of pancreatic ductal adenocarcinoma (PDAC). Nicotine acts through cholinergic nicotinic receptors, preferentially α7 (CHRNA7) that also binds the endogenous ligand SLURP1 (Secreted Ly-6/uPAR-Related Protein 1). The clinical significance of SLURP1 and its interaction with nicotine in PDAC are unclear. We detected similar levels of SLURP1 in sera from healthy donors and patients with chronic pancreatitis or PDAC; higher preoperative values were associated with significantly better survival in patients with resected tumors. Pancreatic tissue was not a source of circulating SLURP1 but contained diverse CHRNA7-expressing cells, preferentially epithelial and immune, whereas stromal stellate cells and a quarter of the tumor cells lacked CHRNA7. The CHRNA7 mRNA levels were decreased in PDAC, and CHRNA7^high-PDAC patients lived longer. In CHRNA7^high COLO357 and PANC-1 cultures, opposing activities of SLURP1 (anti-malignant/CHRNA7-dependent) and nicotine (pro-malignant/CHRNA7-infidel) were exerted without reciprocally interfering with receptor binding or downstream signaling. These data suggested that the ligands act independently and abolish each other’s effects through a mechanism resembling functional antagonism. Thus, SLURP1 might represent an inborn anti-PDAC defense being sensitive to and counteracting nicotine. Boosting SLURP1-CHRNA7 interaction might represent a novel strategy for treatment in high-risk individuals, i.e., smokers with pancreatic cancer.

Functional Assessment of Children and Adolescents with Symbrachydactyly: A Unilateral Hand Malformation

BACKGROUND

We studied children and adolescents with symbrachydactyly to determine whether hand function depends on digit opposability and whether scores for function and quality-of-life measures differ from population norms.

METHODS

Participants were grouped on the basis of hand morphology: Group A lacked opposable digits, and Group B had ≥2 digits that were opposable. The groups were compared with each other and with norms with respect to pinch strength, the performance of bimanual activities and in-hand manipulation, and questionnaires regarding psychosocial status and the ability to perform activities of daily living (ADLs). Participants and parents also rated the appearance and function of the hand.

RESULTS

Pinch strength was higher for participants in Group B (4.1 compared with 2.4 kg; p = 0.008), but the groups did not differ with respect to the proportion of participants outside of pinch norms. Participants in Group B were more likely to actively use their affected hand to perform bimanual activities (p ≤ 0.0009), and to use normal or supination strategies to accomplish in-hand manipulation (p = 0.031). The groups did not differ in the proportion of ADLs rated "difficult" or "impossible," and both groups tested within normal limits for psychosocial function. Participants from both groups and their parents rated their satisfaction with hand appearance and function similarly high.

CONCLUSIONS

Participants with ≥2 opposable digits incorporated their hand better in bimanual activities and used more effective strategies to accomplish in-hand manipulation than those who did not. These groups reported no difference in the ability to perform ADLs or with psychosocial function, which was within the normal range. Children and adolescents with symbrachydactyly demonstrated and reported a high level of function in all domains of validated function tests. This study provides information to help parents of children with a unilateral hand malformation understand their child's potential function, and assist surgeons with recommending treatment.

LEVEL OF EVIDENCE

Prognostic Level III. See Instructions for Authors for a complete description of levels of evidence.

Abstract 5925: Mapping the molecular communication within the tumor microenvironment of pancreatic cancer as well as between tumor and peritumoral tissue

We are analyzing in detail the molecular communication between the different cell types in the microenvironment of pancreatic ductal adenocarcinomas (PDAC). Also, its regulation is being investigated, looking at aspects such as the kind and mixture of molecules needed for triggering a particular regulative function, and unraveling the inter- and intracellular processes utilized to transmit a molecular message.

Although a rare tumor entity, adding up to only about 3% of all cancer cases in the Western world, PDAC is the fourth most frequent cause of cancer-related death; mortality is nearly identical to incidence. There is no real remedy apart from surgery, which can be applied to only 10 to 20% of patients. Even then, basically all patients will experience tumor recurrence.

Our study is based on a large basic set of data at the levels of DNA, RNA and protein that was generated from some 1000 pancreatic tumor samples [1], supplemented with information from studies that aim at an elucidation of functional molecules and comparative analyses in other tumors. This has already led to the creation of basic functional knowledge about metastasis [e.g., 2], the establishment of means for diagnosis [3, 4], an accurate disease prognosis [1], the characterization of communication processes [5] and the identification of new therapeutic avenues [6].

At the conference, we will report about the status of mapping particularly the protein-mediated communication between the different cell types in the tumor microenvironment. Also, we will show results about the effect that PDAC tissue has on the wider peritumoral environment and vice versa. The peritumoral tissue is exhibiting a field defect that does not seem to be dependent on DNA-methylation. A comparison of PDAC and cystic pancreatic tumors revealed that differences in communicating with the peritumoral tissue could actually be more important to the known pathological difference between the two cancer entities than the molecular variations in the tumor cells.

1. Bauer et al. (2017), work submitted for publication

2. Botla et al. (2016) Cancer Res. 76, 4149-4159

3. Keller et al. (2014) BMC Med. 12, 224

4. Moskalev et al. (2015) Oncotarget 6, 4418-4427

5. Dror et al. (2016) Nature Cell Biol. 18, 1006-1017

6. Jandaghi et al. (2016) Gastroenterology, in press (doi: 10.1053/j.gastro.2016.08.040)

www.dkfz.de/funct_genome/

Note: This abstract was not presented at the meeting.

Citation Format: Mohamed S. Alhamdani, Andrea S. Bauer, Jörg D. Hoheisel. Mapping the molecular communication within the tumor microenvironment of pancreatic cancer as well as between tumor and peritumoral tissue [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 5925. doi:10.1158/1538-7445.AM2017-5925

Ultrasound Screening for Posterior Shoulder Dislocation in Infants with Persistent Brachial Plexus Birth Palsy

BACKGROUND

Early detection of posterior shoulder dislocation in infants with brachial plexus birth palsy (BPBP) is essential, but it may be difficult to accomplish with physical examination alone. The aim of this study was to determine the prevalence of shoulder dislocation in patients with BPBP using ultrasound and to identify which physical examination measurements correlated most with dislocation in these patients.

METHODS

This study was a retrospective review of data obtained in an ultrasound screening program of infants with BPBP born from January 2011 to April 2014. Physical examination included the use of the Active Movement Scale (AMS) and measurement of passive external rotation of the shoulder. Ultrasound measurements included PHHD (percentage of the humeral head displaced posterior to the axis of the scapula) and the alpha angle (intersection of the posterior scapular margin with a line tangential to the humeral head through the glenoid). Shoulder dislocation was defined as both a PHHD of >0.5 and an alpha angle of >30°.

RESULTS

Of sixty-six infants who had undergone a total of 118 ultrasound examinations (mean, 1.8; range, 1 to 5), 19 (29%) demonstrated shoulder dislocation with the shoulder positioned in internal rotation; the dislocation was first detected between 2.1 and 10.5 months of age. Infants with a dislocated shoulder demonstrated significantly less mean passive external rotation in adduction (mean, 45.8° versus 71.4°, p < 0.001) and a greater difference between internal rotation and external rotation AMS scores (mean, 5.5-point versus 3.3-point difference, p < 0.001) than those without shoulder dislocation. Passive external rotation in adduction was a better measure for discriminating between dislocation and no dislocation (area under receiver operating characteristic curve [AUC] = 0.89) than was the difference between internal and external rotation AMS scores (AUC = 0.73). A cutoff of 60° of passive external rotation in adduction (≤60° versus° >60) yielded a sensitivity of 94% and a specificity of 69%.

CONCLUSIONS

Shoulder dislocation is common in infants with BPBP; 29% of the infants presenting to our tertiary care center had a dislocation during their first year of life. Ultrasound shoulder screening is appropriate for infants with BPBP. If passive external rotation in adduction is used to determine which infants should undergo ultrasound, ≤60° should be utilized as the criterion to achieve appropriate sensitivity.

LEVEL OF EVIDENCE

Therapeutic Level IV. See Instructions for Authors for a complete description of levels of evidence.

Neonatal Magnetic Resonance Imaging Without Sedation Correlates With Injury Severity in Brachial Plexus Birth Palsy

PURPOSE

Which infants with brachial plexus birth palsy (BPBP) should undergo microsurgical plexus reconstruction remains controversial. The current gold standard for the decision for plexus reconstruction is serial clinical examinations, but this approach obviates the possibility of early surgical treatment. We hypothesize that a new technique using 3-dimensional volumetric proton density magnetic resonance imaging (MRI) without sedation can evaluate the severity of BPBP injury earlier than serial clinical examinations.

METHODS

Infants were prospectively enrolled prior to 12 weeks of age and imaged using 3 Tesla MRI without sedation. Clinical scores were collected at all visits. The imaging findings were graded based on the number of injured levels and the severity of each injury, and a radiological score was calculated. All infants were followed at least until the decision for surgery was made based on clinical examination.

RESULTS

Nine infants completed the MRI scan and clinical follow-up. The average Toronto score at presentation was 4.4 out of 10 (range, 0-8.2); the average Active Movement Scale score was 50 out of 105 (range, 0-86). Four infants required surgery: 2 because of a flail limb and Horner syndrome and 2 owing to failure to recover antigravity elbow flexion by age 6 months. Radiological scores ranged from 0 to 18 out of a maximum score of 25. The average radiological score for those infants who required surgery was 12 (range, 6.5-18), whereas the average score for infants who did not require surgery was 3.5 (range, 0-8).

CONCLUSIONS

Three-dimensional proton density MRI can evaluate spinal nerve roots in infants without the need for radiation, contrast agents, or sedation. These data suggest that MRI can help determine the severity of injury earlier than clinical examination in infants with BPBP, although further study of a larger sample of infants with varying severity of disease is necessary.

TYPE OF STUDY/LEVEL OF EVIDENCE

Diagnostic II.

Tumor cells interact with red blood cells via galectin-4 - a short report

BACKGROUND

The ability of tumor cells to invade and metastasize is relevant to the process of cancer progression and, as such, it represents an obstacle to cancer cure. So far, limited information is available on interactions between circulating tumor cells and blood cells. It is well-documented that galectin-4 is upregulated in many types of tumor cells and is involved in metastasis. Here, we address the hypothesis that tumor cells may interact with red blood cells (RBCs) via galectin-4.

METHODS

High galectin-4 expressing colon, normal pancreatic and pancreatic cancer-derived cell lines (n = 5) were incubated with peripheral blood cells from different donors. Their interactions and associated proteins were examined by immunostaining and live cell imaging.

RESULTS

We found that (endogenous or exogenous) galectin-4 expressing tumor cells interact directly with RBCs. We also observed an accumulation of galectin-4 and human blood group antigens at the contact sites between these cells. By comparing the number of RBCs attaching to each tumor cell, we found that cells with high pre-incubation expression levels of galectin-4 attached significantly more RBCs than those with low expression levels (p < 1 × 10^-7). Conversely, we found that RBC attachment induces galectin-4 expression in tumor cells.

CONCLUSIONS

From our data we conclude that tumor cells directly interact with red blood cells via galectin-4.

Expression of DRD2 Is Increased in Human Pancreatic Ductal Adenocarcinoma and Inhibitors Slow Tumor Growth in Mice

BACKGROUND & AIMS

Incidence of and mortality from pancreatic ductal adenocarcinoma (PDAC), the most common form of pancreatic cancer, are almost equivalent, so better treatments are needed. We studied gene expression profiles of PDACs and the functions of genes with altered expression to identify new therapeutic targets.

METHODS

We performed microarray analysis to analyze gene expression profiles of 195 PDAC and 41 non-tumor pancreatic tissue samples. We undertook an extensive analysis of the PDAC transcriptome by superimposing interaction networks of proteins encoded by aberrantly expressed genes over signaling pathways associated with PDAC development to identify factors that might alter regulation of these pathways during tumor progression. We performed tissue microarray analysis to verify changes in expression of candidate protein using an independent set of 152 samples (40 nontumor pancreatic tissues, 63 PDAC sections, and 49 chronic pancreatitis samples). We validated the functional relevance of the candidate molecule using RNA interference or pharmacologic inhibitors in pancreatic cancer cell lines and analyses of xenograft tumors in mice.

RESULTS

In an analysis of 38,276 human genes and loci, we identified 1676 genes that were significantly up-regulated and 1166 genes that were significantly down-regulated in PDAC compared with nontumor pancreatic tissues. One gene that was up-regulated and associated with multiple signaling pathways that are dysregulated in PDAC was G protein subunit αi2, which has not been previously associated with PDAC. G protein subunit αi2 mediates the effects of dopamine receptor D2 (DRD2) on cyclic adenosine monophosphate signaling; PDAC tissues had a slight but significant increase in DRD2 messenger RNA. Levels of DRD2 protein were substantially increased in PDACs, compared with non-tumor tissues, in tissue microarray analyses. RNA interference knockdown of DRD2 or inhibition with pharmacologic antagonists (pimozide and haloperidol) reduced proliferation of pancreatic cancer cells, induced endoplasmic reticulum stress and apoptosis, and reduced cell migration. RNA interference knockdown of DRD2 in pancreatic tumor cells reduced growth of xenograft tumors in mice, and administration of the DRD2 inhibitor haloperidol to mice with orthotopic xenograft tumors reduced final tumor size and metastasis.

CONCLUSIONS

In gene expression profile analysis of PDAC samples, we found the DRD2 signaling pathway to be activated. Inhibition of DRD2 in pancreatic cancer cells reduced proliferation and migration, and slowed growth of xenograft tumors in mice. DRD2 antagonists routinely used for management of schizophrenia might be tested in patients with pancreatic cancer.

Non-Sedated Rapid Volumetric Proton Density MRI Predicts Neonatal Brachial Plexus Birth Palsy Functional Outcome

BACKGROUND AND PURPOSE

The current prognostic biomarker of functional outcome in brachial plexus birth palsy is serial clinical examination throughout the first 6 months of age. This can delay surgical treatment and prolong parental anxiety in neonates who will recover spontaneously. A potentially superior biomarker is a volumetric proton density MRI performed at clinical presentation and within the first 12 weeks of life, providing a high spatial and contrast resolution examination in 4 minutes.

METHODS

Nine neonates ranging in age from 4 to 9 weeks who presented with brachial plexus birth palsy were enrolled. All subjects underwent non-sedated 3 Tesla MRI with Cube Proton Density MRI sequence at the same time as their initial clinical visit. Serial clinical examinations were conducted at routine 4 week intervals and the functional performance scores were recorded. MRI findings were divided into pre-ganglionic and post-ganglionic injuries and a radiological scoring system (Shriners Radiological Score) was developed for this study.

RESULTS

Proton Density MRI was able to differentiate between pre-ganglionic and post-ganglionic injuries. Radiological scores (Shriners Radiological Score) correlated better with functional performance at 6 months of age (P = .022) than the initial clinical examinations (Active Movement Scale P = .213 and Toronto P = .320).

CONCLUSIONS

Rapid non-sedated volumetric Cube Proton Density MRI protocol performed at initial clinical presentation can accurately grade severity of brachial plexus birth palsy injury and predict functional performance at 6 months of age.

Symbrachydactyly

Background: Symbrachydactyly is a unilateral congenital hand malformation characterized by failure of formation of fingers and the presence of rudimentary digit nubbins. The management is variable and are investigated in this review. Methods: A detailed review of the literature was compiled into succinct clinically relevant categories. Results: Etiology, classification, non-surgical management, surgical intervention, and patient oriented outcomes are discussed. Conclusions: All interventions should prioritize realistic, evidence-supported appearance and functional gains. Studies of the baseline function and quality of life of children with symbrachydactyly would allow surgeons to better understand functional changes associated with various interventions and would help surgeons and parents to make the best treatment decisions.

Early Epigenetic Downregulation of microRNA-192 Expression Promotes Pancreatic Cancer Progression

Pancreatic ductal adenocarcinoma (PDAC) is characterized by very early metastasis, suggesting the hypothesis that metastasis-associated changes may occur prior to actual tumor formation. In this study, we identified miR-192 as an epigenetically regulated suppressor gene with predictive value in this disease. miR-192 was downregulated by promoter methylation in both PDAC and chronic pancreatitis, the latter of which is a major risk factor for the development of PDAC. Functional studies in vitro and in vivo in mouse models of PDAC showed that overexpression of miR-192 was sufficient to reduce cell proliferation and invasion. Mechanistic analyses correlated changes in miR-192 promoter methylation and expression with epithelial-mesenchymal transition. Cell proliferation and invasion were linked to altered expression of the miR-192 target gene SERPINE1 that is encoding the protein plasminogen activator inhibitor-1 (PAI-1), an established regulator of these properties in PDAC cells. Notably, our data suggested that invasive capacity was altered even before neoplastic transformation occurred, as triggered by miR-192 downregulation. Overall, our results highlighted a role for miR-192 in explaining the early metastatic behavior of PDAC and suggested its relevance as a target to develop for early diagnostics and therapy. Cancer Res; 76(14); 4149-59. ©2016 AACR.

Promoter SNPs rs116896264 and rs73933062 form a distinct haplotype and are associated with galectin-4 overexpression in colorectal cancer

Galectin-4 is a member of the galectin family which consists of 15 galactoside-binding proteins. Previously, galectin-4 has been shown to have a role in cancer progression and metastasis and it is found upregulated in many solid tumours, including colorectal cancer (CRC). Recently, the role in the metastatic process was suggested to be via promoting cancer cells to adhere to blood vascular endothelium. In the present study, the regulatory region of LGALS4 (galectin-4) in seven colon cell lines was investigated with respect to genetic variation that could be linked to expression levels and therefore a tumourigenic effect. Interestingly, qRT-PCR and sequencing results revealed that galectin-4 upregulation is associated with SNPs rs116896264 and rs73933062. By use of luciferase reporter- and pull-down assays, we confirmed the association between the gene upregulation and the two SNPs. Also, using pull-down assay followed by mass spectrometry, we found that the presence rs116896264 and rs73933062 is changing transcription factors binding sites. In order to assess the frequencies of the two SNPs among colon cancer patients and healthy individuals, we genotyped 75 colon cancer patients, 12 patients with adenomatous polyposis and 17 patients with ulcerative colitis and we performed data mining in the 1000 genomes databank. We found the two SNPs co-occuring in 21% of 75 CRC patients, 0 out of 12 patients of adenomatous polyposis, and 6 out of 17 patients (35%) with ulcerative colitis. Both in the patient samples and in the 1000 genomes project, the two SNPs were found to co-occur whenever present (D' = 1).

Pediatric Trigger Digits

Pediatric trigger thumb presents not at birth but early in childhood. Most evidence suggests that it is caused by a developmental size mismatch between the flexor pollicis longus tendon and its sheath. Patients generally present with the thumb interphalangeal joint locked in flexion. Surgical reviews report near universally excellent outcomes after open release of the A1 pulley. However, recent reports indicate that there may be a role for nonsurgical treatment for families that are willing to wait several years for possible spontaneous resolution of the deformity. Triggering in digits other than the thumb in children is generally associated with an underlying diagnosis including anatomic abnormalities of the tendons, and metabolic, inflammatory, and infectious etiologies. Although some have advocated nonsurgical treatment, surgery is often necessary to address the underlying anatomic etiology. More extensive surgery beyond simple A1 pulley release is often required, including release of the A3 pulley and resection of a slip of the flexor digitorum superficialis tendon.