Genomic sequence of a Lyme disease spirochaete, Borrelia burgdorferi

The genome of the bacterium Borrelia burgdorferi B31, the aetiologic agent of Lyme disease, contains a linear chromosome of 910,725 base pairs and at least 17 linear and circular plasmids with a combined size of more than 533,000 base pairs. The chromosome contains 853 genes encoding a basic set of proteins for DNA replication, transcription, translation, solute transport and energy metabolism, but, like Mycoplasma genitalium, it contains no genes for cellular biosynthetic reactions. Because B. burgdorferi and M. genitalium are distantly related eubacteria, we suggest that their limited metabolic capacities reflect convergent evolution by gene loss from more metabolically competent progenitors. Of 430 genes on 11 plasmids, most have no known biological function; 39% of plasmid genes are paralogues that form 47 gene families. The biological significance of the multiple plasmid-encoded genes is not clear, although they may be involved in antigenic variation or immune evasion.

Complete genome sequence of Treponema pallidum, the syphilis spirochete

The complete genome sequence of Treponema pallidum was determined and shown to be 1,138,006 base pairs containing 1041 predicted coding sequences (open reading frames). Systems for DNA replication, transcription, translation, and repair are intact, but catabolic and biosynthetic activities are minimized. The number of identifiable transporters is small, and no phosphoenolpyruvate:phosphotransferase carbohydrate transporters were found. Potential virulence factors include a family of 12 potential membrane proteins and several putative hemolysins. Comparison of the T. pallidum genome sequence with that of another pathogenic spirochete, Borrelia burgdorferi, the agent of Lyme disease, identified unique and common genes and substantiates the considerable diversity observed among pathogenic spirochetes.

Higher Absolute Lymphocyte Counts Predict Lower Mortality from Early-Stage Triple-Negative Breast Cancer

Purpose: Tumor-infiltrating lymphocytes (TIL) in pretreatment biopsies are associated with improved survival in triple-negative breast cancer (TNBC). We investigated whether higher peripheral lymphocyte counts are associated with lower breast cancer-specific mortality (BCM) and overall mortality (OM) in TNBC.Experimental Design: Data on treatments and diagnostic tests from electronic medical records of two health care systems were linked with demographic, clinical, pathologic, and mortality data from the California Cancer Registry. Multivariable regression models adjusted for age, race/ethnicity, socioeconomic status, cancer stage, grade, neoadjuvant/adjuvant chemotherapy use, radiotherapy use, and germline BRCA1/2 mutations were used to evaluate associations between absolute lymphocyte count (ALC), BCM, and OM. For a subgroup with TIL data available, we explored the relationship between TILs and peripheral lymphocyte counts.Results: A total of 1,463 stage I-III TNBC patients were diagnosed from 2000 to 2014; 1,113 (76%) received neoadjuvant/adjuvant chemotherapy within 1 year of diagnosis. Of 759 patients with available ALC data, 481 (63.4%) were ever lymphopenic (minimum ALC <1.0 K/μL). On multivariable analysis, higher minimum ALC, but not absolute neutrophil count, predicted lower OM [HR = 0.23; 95% confidence interval (CI), 0.16-0.35] and BCM (HR = 0.19; CI, 0.11-0.34). Five-year probability of BCM was 15% for patients who were ever lymphopenic versus 4% for those who were not. An exploratory analysis (n = 70) showed a significant association between TILs and higher peripheral lymphocyte counts during neoadjuvant chemotherapy.Conclusions: Higher peripheral lymphocyte counts predicted lower mortality from early-stage, potentially curable TNBC, suggesting that immune function may enhance the effectiveness of early TNBC treatment. Clin Cancer Res; 24(12); 2851-8. ©2018 AACR.

Characterization of blunt chest trauma in a long-term porcine model of severe multiple trauma

Chest trauma has a significant relevance on outcome after severe trauma. Clinically, impaired lung function typically occurs within 72 hours after trauma. However, the underlying pathophysiological mechanisms are still not fully elucidated. Therefore, we aimed to establish an experimental long-term model to investigate physiological, morphologic and inflammatory changes, after severe trauma. Male pigs (sus scrofa) sustained severe trauma (including unilateral chest trauma, femur fracture, liver laceration and hemorrhagic shock). Additionally, non-injured animals served as sham controls. Chest trauma resulted in severe lung damage on both CT and histological analyses. Furthermore, severe inflammation with a systemic increase of IL-6 (p = 0.0305) and a local increase of IL-8 in BAL (p = 0.0009) was observed. The pO₂/FiO₂ ratio in trauma animals decreased over the observation period (p < 0.0001) but not in the sham group (p = 0.2967). Electrical Impedance Tomography (EIT) revealed differences between the traumatized and healthy lung (p < 0.0001). In conclusion, a clinically relevant, long-term model of blunt chest trauma with concomitant injuries has been developed. This reproducible model allows to examine local and systemic consequences of trauma and is valid for investigation of potential diagnostic or therapeutic options. In this context, EIT might represent a radiation-free method for bedside diagnostics.

Breast cancer treatment across health care systems: linking electronic medical records and state registry data to enable outcomes research

BACKGROUND

Understanding of cancer outcomes is limited by data fragmentation. In the current study, the authors analyzed the information yielded by integrating breast cancer data from 3 sources: electronic medical records (EMRs) from 2 health care systems and the state registry.

METHODS

Diagnostic test and treatment data were extracted from the EMRs of all patients with breast cancer treated between 2000 and 2010 in 2 independent California institutions: a community-based practice (Palo Alto Medical Foundation; "Community") and an academic medical center (Stanford University; "University"). The authors incorporated records from the population-based California Cancer Registry and then linked EMR-California Cancer Registry data sets of Community and University patients.

RESULTS

The authors initially identified 8210 University patients and 5770 Community patients; linked data sets revealed a 16% patient overlap, yielding 12,109 unique patients. The percentage of all Community patients, but not University patients, treated at both institutions increased with worsening cancer prognostic factors. Before linking the data sets, Community patients appeared to receive less intervention than University patients (mastectomy: 37.6% vs 43.2%; chemotherapy: 35% vs 41.7%; magnetic resonance imaging: 10% vs 29.3%; and genetic testing: 2.5% vs 9.2%). Linked Community and University data sets revealed that patients treated at both institutions received substantially more interventions (mastectomy: 55.8%; chemotherapy: 47.2%; magnetic resonance imaging: 38.9%; and genetic testing: 10.9% [P < .001 for each 3-way institutional comparison]).

CONCLUSIONS

Data linkage identified 16% of patients who were treated in 2 health care systems and who, despite comparable prognostic factors, received far more intensive treatment than others. By integrating complementary data from EMRs and population-based registries, a more comprehensive understanding of breast cancer care and factors that drive treatment use was obtained.

Impact of age on the clinical outcomes of major trauma

PURPOSE

In view of demographic changes over the past few decades, the average age of trauma patients is progressively increasing. We therefore aimed to summarize the specific characteristics of geriatric trauma and to identify potential fields for further research to improve the care of elderly trauma patients.

METHODS

Review of the literature.

RESULTS

Due to the diverse risk factors (e.g., pre-existing conditions, limited physiological reserve), geriatric patients are prone to developing severe complications, even after less severe trauma. Yet, age is not considered as the only predictor of worse outcomes, and it should not be considered the only criterion for limiting care in those patients. It is crucial that age-specific treatment guidelines are developed to optimize the outcomes for senior trauma patients. Based on the current literature, these guidelines should emphasize the importance of field triage directly to a trauma center, along with the activation of the trauma team. Furthermore, early intensive monitoring, aggressive resuscitation, and time of surgical intervention are of upmost importance to reduce mortality.

CONCLUSION

The impact of several factors [age, premedical conditions (PMC), decreased physiological reserves, and impaired immune function] on the post-traumatic course of elderly trauma patients needs to be clarified in future experimental and clinical studies for the early identification of geriatric high-risk patients and for the development of age-adapted therapeutic strategies.

Indications for bullet removal: overview of the literature, and clinical practice guidelines for European trauma surgeons

PURPOSE

The incidence of gunshot wounds from civilian firearms is increasing. Despite this fact, guidelines on indications for bullet removal are scarce. In this analysis, we combine an overview of the available literature in these rare entities with our experiences in our own clinical practices.

METHODS

We conducted a systematic literature search of computerized bibliographic databases (Medline, EMBASE, and the Cochrane Central Register). The local experience of the authors was reviewed in light of the available literature.

RESULTS

145 full-text articles were suitable for further evaluation. Only six retrospective studies were available, and no prospective study could be retrieved. Most of the articles were case reports. In the South African co-author's own clinical practice, approximately 800 patients are treated per year with gunshot wounds.

CONCLUSIONS

In summary, there are only a few clear indications for bullet removal. These include bullets found in joints, CSF, or the globe of the eye. Fragments leading to impingement on a nerve or a nerve root, and bullets lying within the lumen of a vessel, resulting in a risk of ischemia or embolization, should be removed. Rare indications are lead poisoning caused by a fragment, and removal that is required for a medico-legal examination. In all other cases the indication should be critically reviewed.

Omission of Radiotherapy After Breast-Conserving Surgery for Women With Breast Cancer With Low Clinical and Genomic Risk: 5-Year Outcomes of IDEA

PURPOSE

Multiple studies have shown a low risk of ipsilateral breast events (IBEs) or other recurrences for selected patients age 65-70 years or older with stage I breast cancers treated with breast-conserving surgery (BCS) and endocrine therapy (ET) without adjuvant radiotherapy. We sought to evaluate whether younger postmenopausal patients could also be successfully treated without radiation therapy, adding a genomic assay to classic selection factors.

METHODS

Postmenopausal patients age 50-69 years with pT1N0 unifocal invasive breast cancer with margins ≥2 mm after BCS whose tumors were estrogen receptor-positive, progesterone receptor-positive, and human epidermal growth factor receptor 2-negative with Oncotype DX 21-gene recurrence score ≤18 were prospectively enrolled in a single-arm trial of radiotherapy omission if they consented to take at least 5 years of ET. The primary end point was the rate of locoregional recurrence 5 years after BCS.

RESULTS

Between June 2015 and October 2018, 200 eligible patients were enrolled. Among the 186 patients with clinical follow-up of at least 56 months, overall and breast cancer-specific survival rates at 5 years were both 100%. The 5-year freedom from any recurrence was 99% (95% CI, 96 to 100). Crude rates of IBEs for the entire follow-up period for patients age 50-59 years and age 60-69 years were 3.3% (2/60) and 3.6% (5/140), respectively; crude rates of overall recurrence were 5.0% (3/60) and 3.6% (5/140), respectively.

CONCLUSION

This trial achieved a very low risk of recurrence using a genomic assay in combination with classic clinical and biologic features for treatment selection, including postmenopausal patients younger than 60 years. Long-term follow-up of this trial and others will help determine whether the option of avoiding initial radiotherapy can be offered to a broader group of women than current guidelines recommend.

Assessment of coincidence and defect sizes in Bankart and Hill-Sachs lesions after anterior shoulder dislocation: a radiological study

OBJECTIVE

Bankart and Hill-Sachs lesions are often associated with anterior shoulder dislocation. The MRI technique is sensitive in diagnosing both injuries. The aim of this study was to investigate Bankart and Hill-Sachs lesions with MRI to determine the correlation in occurrence and defect sizes of these lesions.

METHODS

Between 2006 and 2013, 446 patients were diagnosed with an anterior shoulder dislocation and 105 of these patients were eligible for inclusion in the study. All patients were examined using MRI. Bankart lesions were classified as cartilaginous or bony lesions. Hill-Sachs lesions were graded I-III using a modified Calandra classification.

RESULTS

The co-occurrence of injuries was high [odds ratio (OR) = 11.47; 95% confidence interval (CI) = 3.60-36.52; p < 0.001]. Patients older than 29 years more often presented with a bilateral injury (OR = 16.29; 95% CI = 2.71-97.73; p = 0.002). A correlation between a Bankart lesion and the grade of a Hill-Sachs lesion was found (ρ = 0.34; 95% CI = 0.16-0.49; p < 0.001). Bankart lesions co-occurred more often with large Hill-Sachs lesions (O  = 1.24; 95% CI = 1.02-1.52; p = 0.033).

CONCLUSION

If either lesion is diagnosed, the patient is 11 times more likely to have suffered the associated injury. The size of a Hill-Sachs lesion determines the co-occurrence of cartilaginous or bony Bankart lesions. Age plays a role in determining the type of Bankart lesion as well as the co-occurrence of Bankart and Hill-Sachs lesions.

ADVANCES IN KNOWLEDGE

This study is the first to demonstrate the use of high-quality MRI in a reasonably large sample of patients, a positive correlation of Bankart and Hill-Sachs lesions in anterior shoulder dislocations and an association between the defect sizes.

Cardiac Depression in Pigs after Multiple Trauma - Characterization of Posttraumatic Structural and Functional Alterations

The purpose of this study was to define the relationship between cardiac depression and morphological and immunological alterations in cardiac tissue after multiple trauma. However, the mechanistic basis of depressed cardiac function after trauma is still elusive. In a porcine polytrauma model including blunt chest trauma, liver laceration, femur fracture and haemorrhage serial trans-thoracic echocardiography was performed and correlated with cellular cardiac injury as well as with the occurrence of extracellular histones in serum. Postmortem analysis of heart tissue was performed 72 h after trauma. Ejection fraction and shortening fraction of the left ventricle were significantly impaired between 4 and 27 h after trauma. H-FABP, troponin I and extracellular histones were elevated early after trauma and returned to baseline after 24 and 48 h, respectively. Furthermore, increased nitrotyrosine and Il-1β generation and apoptosis were identified in cardiac tissue after trauma. Main structural findings revealed alteration of connexin 43 (Cx43) and co-translocation of Cx43 and zonula occludens 1 to the cytosol, reduction of α-actinin and increase of desmin in cardiomyocytes after trauma. The cellular and subcellular events demonstrated in this report may for the first time explain molecular mechanisms associated with cardiac dysfunction after multiple trauma.

Continuing Medical Student Education During the Coronavirus Disease 2019 (COVID-19) Pandemic: Development of a Virtual Radiation Oncology Clerkship

Purpose

Our institution cancelled all in-person clerkships owing to the coronavirus disease 2019 pandemic. In response, we designed a virtual radiation oncology medical student clerkship.

Methods and Materials

We convened an advisory panel to design a virtual clerkship curriculum. We implemented clerkship activities using a cloud-based learning management system, video web conferencing systems, and a telemedicine portal. Students completed assessments pre- and postclerkship to provide data to improve future versions of the clerkship.

Results

The virtual clerkship spans 2 weeks and is graded pass or fail. Students attend interactive didactic sessions during the first week and participate in virtual clinic and give talks to the department during the second week. Didactic sessions include lectures, case-based discussions, treatment planning seminars, and material adapted from the Radiation Oncology Education Collaborative Study Group curriculum. Students also attend virtual departmental quality assurance rounds, cancer center seminars, and multidisciplinary tumor boards. The enrollment cap was met during the first virtual clerkship period (April 27 through May 8, 2020), with a total of 12 students enrolling.

Conclusions

Our virtual clerkship can increase student exposure and engagement in radiation oncology. Data on clerkship outcomes are forthcoming.

Histologic subtypes of breast cancer following radiotherapy for Hodgkin lymphoma

BACKGROUND

The purpose of the study was to determine whether breast cancers (BCs) that develop in women previously irradiated for Hodgkin lymphoma (HL) are biologically similar to sporadic BC.

MATERIALS AND METHODS

We retrospectively reviewed the charts of patients who developed BC after radiotherapy (RT) for HL. Tumors were classified as ductal carcinoma in situ (DCIS) or invasive carcinoma. Invasive carcinomas were further characterized according to the subtype: hormone receptor (HR)+/human epidermal growth factor receptor 2 (HER2)-, HR+/HER2+, HR-/HER2+, and HR-/HER2-. BCs after HL were compared with four age-matched sporadic, non-breast cancer (BRCA) I or II mutated BCs.

RESULTS

One hundred forty-seven HL patients who were treated with RT between 1966 and 1999 and subsequently developed BCs were identified. Of these, 65 patients with 71 BCs had complete pathologic information. The median age at HL diagnosis was 23 (range, 10-48). The median age at BC diagnosis was 44 (range, 28-66). The median time to developing BC was 20 years. Twenty cancers (28%) were DCIS and 51 (72%) were invasive. Of the 51 invasive cancers, 24 (47%) were HR+/HER2-, 2 (4%) were HR+/HER2+, 5 (10%) were HR-/HER2+, and 20 (39%) were HR-/HER2-. There were no differences in BC histologic subtype according to the age at which patients were exposed to RT, the use of chemotherapy for HL treatment, or the time from RT exposure to the development of BC. In a 4 : 1 age-matched comparison to sporadic BCs, BCs after HL were more likely to be HR-/HER2- (39% versus 14%) and less likely to be HR+/HER2- (47% versus 61%) or HR+/HER2+ (4% versus 14%) (P = 0.0003).

CONCLUSION(S)

BCs arising in previously irradiated breast tissue were more likely to be triple negative compared with age-matched sporadic invasive cancers and less likely to be HR positive. Further studies will be important to determine the molecular pathways of carcinogenesis in breast tissue that is exposed to RT.

Impact of haemorrhagic shock intensity on the dynamic of alarmins release in porcine poly-trauma animal model

PURPOSE

Traumatic insults result in an altered inflammatory response, in which alarmins release has a central role. The impact of haemorrhagic shock intensity on the long-term kinetics of alarmins is not yet fully elucidated. We investigated these aspects in a combined trauma (chest, abdominal, and extremities injury) porcine model with different severities and durations of haemorrhagic shock.

METHODS

After induction of combined trauma (tibia fracture, lung contusion, and liver laceration), haemorrhagic shock was induced at different intensities: moderate haemorrhage (MH; n = 15): mean arterial pressure (MAP) <30 ± 5 mmHg [maximum loss of total blood volume (TBVmax): 45 %] for 90 min, and severe haemorrhage (SH; n = 10): MAP <25 ± 5 mmHg (TBVmax 50 %) for 120 min. Resuscitation was performed using a standardized crystalloid infusion protocol. Animals were mechanically ventilated and underwent ICU-monitoring for 48 h (MH) and 48.5 h (SH). Blood samples were collected over the clinical time course, and systemic levels of serum alarmins [High-Mobility Group Protein B-1 (HMGB-1) and Heat Shock Protein 70 (HSP70)] were measured using an ELISA kit.

RESULTS

Heart rate, systemic blood pressure, lactate, and base excess were significantly altered as a function of haemorrhagic shock in both trauma groups (MH and SH). Systemic HMGB-1 levels were significantly elevated in both trauma groups when compared to the sham group. Haemorrhagic shock severity and duration were positively correlated with HMGB-1 levels and compared to baseline values, concentrations remained significantly increased in SH when compared to MH. On the other hand, we observed a significant decrease in the systemic HSP70 levels of trauma groups (MH, and SH) when compared to the sham group, which was significantly decreased compared to baseline values in SH over the entire time course.

CONCLUSION

Our data show that haemorrhagic shock duration and severity affect the systemic levels of HMGB-1 and HSP70. This early alarmins release after trauma can be used to guide the treatment strategies (e.g. surgical procedures) of polytrauma patients.

A porcine polytrauma model with two different degrees of hemorrhagic shock: outcome related to trauma within the first 48 h

BACKGROUND

An animal polytrauma model was developed, including trunk and extremity injuries combined with hemorrhagic shock and a prolonged post-traumatic phase. This could be useful for the assessment of different therapeutic approaches during intensive care therapy.

METHODS

A standardized polytrauma including lung contusion, liver laceration and lower leg fracture was applied in 25 pigs. They underwent controlled haemorrhage either with a blood volume loss of 45 % and a median arterial pressure (MAP) <30 mmHg/90 min (group L, n = 15) or a 50 % blood loss of and an MAP <25 mmHg/120 min (group H, n = 10). Five non-traumatized pigs served as a control (group C). Subsequently, intensive care treatment was given for an observational period of 48 h.

RESULTS

Both trauma groups showed signs of shock and organ injury (heart rate, MAP and lactate). The frequency of cardiopulmonary resuscitation (CPR) and lung injury was directly related to the severity of the haemorrhagic shock (CPR-group L: 4 of 15 pigs, group H: 4 of 10 pigs; Respiratory failure-group L: 3 of 13, group H: 3 of 9. There was no difference in mortality between trauma groups.

CONCLUSION

The present data suggest that our model reflects the mortality and organ failure of polytrauma in humans during shock and the intensive care period. This suggests that the experimental protocol could be useful for the assessment of therapeutic approaches during the post-traumatic period.

Systemic Inflammation After Radiation Predicts Locoregional Recurrence, Progression, and Mortality in Stage II-III Triple-Negative Breast Cancer

PURPOSE

Patients with triple-negative breast cancer experience high rates of recurrence after radiation, which may be facilitated by the recruitment of circulating tumor cells to proinflammatory microenvironments in the absence of lymphocytes. We hypothesized that patients with lymphopenia and elevated inflammatory hematologic markers after radiation therapy would have an increased risk of locoregional failure.

METHODS AND MATERIALS

With approval, we retrospectively studied a cohort of women treated with adjuvant radiation therapy for stage II-III triple-negative breast cancer. We analyzed the relationship between post-radiation therapy neutrophil:lymphocyte ratio (NLR) and locoregional recurrence by using Cox regression.

RESULTS

One-hundred thirty patients met inclusion criteria, and median follow-up time was 7.6 years. Patients with an NLR ≥3 had a higher rate of locoregional failure (P = .04) and lower overall survival (P = .04). After adjusting for stage (hazard ratio [HR], 5.5; P < .0001) and neoadjuvant chemotherapy (HR, 2.5; P = .0162), NLR was highly predictive of locoregional failure (HR, 1.4; P = .0009). NLR was also highly predictive of overall survival (HR, 1.3; P = .0007) after adjustment for stage and neoadjuvant chemotherapy.

CONCLUSIONS

Innate peripheral inflammation after radiation therapy for triple-negative breast cancer in an immunocompromised setting may be a novel prognostic biomarker for locoregional recurrence, progression, and survival. This finding supports preclinical studies of post-radiation therapy inflammation-mediated tumor progression. Further studies are needed to confirm this finding and develop treatment strategies.

Comparative study on the treatment of Rockwood type III acute acromioclavicular dislocation: Clinical results from the TightRope® technique vs. K-wire fixation

BACKGROUND AND HYPOTHESIS

The aim of this study was to address the inconsistency regarding the operative treatment of Rockwood type III acromioclavicular joint separation. We compared results after single- and double TightRope^® reduction with results after acromioclavicular transfixation via K-wires only and additional ligament augmentation in acute acromioclavicular (AC) joint separations graded Rockwood type III, and hypothesized that the TightRope^® technique leads to better clinical and radiological results.

MATERIALS AND METHODS

We conducted a retrospective clinical cohort study and included 42 consecutive patients (mean age 43 years [24-66]) diagnosed and operatively treated between 2004 and 2012 (mean follow-up was 54.6 months [15-118]). Specific shoulder scores as well as scores reflecting the patients' overall mental and physical health status were used. Radiological evaluation was also performed.

RESULTS

The SF12 test revealed comparability between all subgroups. Specific shoulder tests and a visual analogue scale demonstrated comparable results. Radiographic measurements showed a significant reduction in the AC distance and CC distance after surgery in all subgroups. The early complication rate was 9.5% for all patients, while late complications occurred in 14.3% of all cases.

CONCLUSIONS

Compared to the established methods, the operative TightRope^® procedures represent a safe alternative in Rockwood III injuries. All investigated techniques predominantly led to good and excellent clinical results in acute Rockwood type III AC joint instabilities. Avoidance of material removal and shorter hospital stays appear to speak in favour for the TightRope^® technique.

LEVEL OF EVIDENCE

IV.

A meta-analysis of operative versus nonoperative treatment in 463 scapular neck fractures

BACKGROUND AND AIMS

Treatment of scapular neck fractures remains controversial. Advantages of surgical treatments, such as anatomical restoration of fracture displacement, are counterbalanced by approach morbidity. We conducted a meta-analysis of 463 scapular neck fractures and compared clinical, functional, and radiographical outcomes in operatively and nonoperatively treated scapular neck fractures.

MATERIAL AND METHODS

A literature search was conducted, including the databases PubMed/MEDLINE, Embase, and the Cochrane Database of Systematic Reviews. Manuscripts were included if they reported a precise description of treatment, complications, functional outcomes, and/or radiographic evaluation. Data about day-to-day activities, level of pain-freeness, range of motion, functional grading, and radiographical assessment were pooled and compared using fixed effects models.

RESULTS AND CONCLUSIONS

A total of 22 manuscripts were relevant, including 1 prospective cohort study and 21 retrospective studies. The studies showed a high heterogeneity in the result assessment. Most patients had concomitant injuries. In total, 234 out of the 463 fractures were treated operatively. Pain-freeness and radiographic outcome measurements were significantly better in the operatively treated group, whereas range of motion was significantly improved in the nonoperative treated patients. Complication rate for surgical treatment was about 10%. From the achievable data, there was no bias detected when comparing the two treatment groups. However, those data could not be analyzed for all included studies. For the same reason, the role of additional surgical treatment for concomitant injuries to the shoulder girdle could not be cleared completely. Caution should be exercised, and individual injury patterns have to be taken into consideration when considering the best treatment options.

Reconstruction of a quadriceps tendon tear using Polyvinylidene fluoride sutures and patellar screw fixation: A biomechanical study

BACKGROUND

Acute quadriceps tendon tears are infrequent injuries requiring surgical treatment. Improved stability after surgical repair may allow for earlier weight-bearing and range of motion. Therefore, a new implant was tested and compared with the "gold standard", using transosseous sutures.

METHODS

Quadriceps tendon tears were constructed using a cadaveric model of 12 fresh matched-pair specimens (aged 61-97; mean age: 82 years). The biomechanical testing compared non-absorbable suture anchors (Polyvinylidene fluoride) versus transosseous absorbable sutures (Polydioxanon). Following anatomic reconstruction, the repaired specimens were loaded until they failed (testing machine: Hounsfield H10KM, Redhill, United Kingdom; maximum force: 1000 N; load speed: 25 mm/min; maximum test length: 150 mm; pre-load: 5 N). Values for load until tear displacement, maximum load until complete failure of the construct (pullout or breakage of the sutures or anchors) and stiffness of the reconstruction were recorded.

RESULTS

The stiffness found in the Polyvinylidene fluoride reconstruction (mean 9.83 N/mm) (standard deviation (SD) 7.75) showed a significant increase compared to the Polydioxanon reconstruction (mean 6.66 N/mm (SD 3.32); P=0.045). Transosseous fixation showed comparable results to the suture anchor system. There was no significant difference found in the maximum load to tear displacement (PVDF: 290.88 N (SD 106.01) vs. PDS: 266.75 N (SD 82.61); P=0.358).

CONCLUSIONS

Using the Polyvinylidene fluoride thread showed comparable results to the established method in reconstruction of ruptured quadriceps tendon. Stiffness of the Polyvinylidene fluoride thread reconstruction was even greater than Polydioxanon thread.

CLINICAL RELEVANCE

Improved stiffness may facilitate healing and is suggested as clinical relevance in reconstruction.

[The rotationally stable screw-anchor with trochanteric stabilizing plate (RoSA/TSP) : First results in unstable trochanteric femur fractures]

BACKGROUND

In unstable trochanteric fractures, the extramedullary rotationally stable screw-anchor (RoSA) combines the benefits of the load and rotational stability of the blade with the advantages of the screw (pull-out resistance, compression capability) in a single load carrier, and was designed to prevent femoral neck shortening by using an additional locked trochanteric stabilizing plate (TSP).

OBJECTIVES

The aim of the current prospective cohort study was the clinical evaluation of the RoSA/TSP system regarding the mechanical re-operation rate and the amount of postoperative femoral neck shortening.

METHODS

From September 2011 to January 2014 80 patients with unstable trochanteric fractures underwent internal extramedullary fixation with the RoSA/TSP (Königsee Implantate GmbH, Allendorf, Germany). Due to fracture stability and after induction of compression, additional long locked antitelescoping screws (AT, n = 1-4) were placed reaching the femoral head. Radiological (femoral neck shortening) and clinical re-examination of patients (n = 61) was performed 6-10 weeks and 6-10 months later.

RESULTS

In the 61 re-examined patients (76 %) femoral neck shortening was very low with 2 mm 6-10 months after operation. Re-operations occurred in 8 % (n = 6) and in 4 % (n = 3) as prophylactic surgical intervention. Whereas one-third (4 %) of re-operations occurred due to iatrogenic surgical problems from the first operation two-thirds of patients (8 %) had a re-operation due to delay of bone union (3× nonunion, 3 planned removals of AT-screws to improve healing). The in-hospital mortality was 3 % (n = 2).

CONCLUSIONS

The fixation of unstable trochanteric femur fractures using the RoSA/TSP in a first clinical setting led to a great primary stability, with significant advantages with regard to limited femoral neck shortening. However, the rigidity of the construct with its consequences regarding bone healing can be challenging for the surgeon. Nevertheless, in some cases of revision it could be beneficial for stability.

Hypothermia does not influence liver damage and function in a porcine polytrauma model

BACKGROUND

Previous studies revealed evidence that induced hypothermia attenuates ischemic organ injuries after severe trauma. In the present study, the effect of hypothermia on liver damage was investigated in a porcine long term model of multi-system injury, consisting of blunt chest trauma, penetrating abdominal trauma, musculoskeletal injury, and hemorrhagic shockMETHODS: In 30 pigs, a standardized polytrauma including blunt chest trauma, penetrating abdominal trauma, musculoskeletal injury, and hemorrhagic shock of 45% of total blood volume was induced. Following trauma, hypothermia of 33∘C was induced for 12 h and intensive care treatment was evaluated for 48 h. As outcome parameters, we assessed liver function and serum transaminase levels as well as a histopathological analysis of tissue samples. A further 10 animals served as controls.

RESULTS

Serum transaminase levels were increased at the end of the observation period following hypothermia without reaching statistical significance compared to normothermic groups. Liver function was preserved (p⩽ 0.05) after the rewarming period in hypothermic animals but showed no difference at the end of the observation period. In H&E staining, cell death was slightly increased hypothermic animals and caspase-3 staining displayed tendency towards more apoptosis in hypothermic group as well.

CONCLUSIONS

Induction of hypothermia could not significantly improve hepatic damage during the first 48 h following major trauma. Further studies focusing on multi-organ failure including a longer observation period are required to illuminate the impact of hypothermia on hepatic function in multiple trauma patients.

Predicting Adverse Cardiac Events After Radiotherapy for Locally Advanced Non-Small Cell Lung Cancer

Background

Radiotherapy may cause grade ≥3 cardiac events, necessitating a better understanding of risk factors. The potential predictive role of imaging biomarkers with radiotherapy doses for cardiac event occurrence has not been studied.

Objectives

The aim of this study was to establish the associations between cardiac substructure dose and coronary artery calcium (CAC) scores and cardiac event occurrence.

Methods

A retrospective cohort analysis included patients with locally advanced non-small cell lung cancer treated with radiotherapy (2006-2018). Cardiac substructures, including the left anterior descending coronary artery, left main coronary artery, left circumflex coronary artery, right coronary artery, and TotalLeft (left anterior descending, left main, and left circumflex coronary arteries), were contoured. Doses were measured in 2-Gy equivalent units, and visual CAC scoring was compared with automated scoring. Grade ≥3 adverse cardiac events were recorded. Time-dependent receiver-operating characteristic modeling, the log-rank statistic, and competing-risk models were used to measure prediction performance, threshold modeling, and the cumulative incidence of cardiac events, respectively.

Results

Of the 233 eligible patients, 61.4% were men, with a median age of 68.1 years (range: 34.9-90.7 years). The median follow-up period was 73.7 months (range: 1.6-153.9 months). Following radiotherapy, 22.3% experienced cardiac events, within a median time of 21.5 months (range: 1.7-118.9 months). Visual CAC scoring showed significant correlation with automated scoring (r = 0.72; P < 0.001). In a competing-risk multivariable model, TotalLeft volume receiving 15 Gy (per 1 cc; HR: 1.38; 95% CI: 1.11-1.72; P = 0.004) and CAC score >5 (HR: 2.51; 95% CI: 1.08-5.86; P = 0.033) were independently associated with cardiac events. A model incorporating age, TotalLeft CAC (score >5), and volume receiving 15 Gy demonstrated a higher incidence of cardiac events for a high-risk group (28.9%) compared with a low-risk group (6.9%) (P < 0.001).

Conclusions

Adverse cardiac events associated with radiation occur in more than 20% of patients undergoing thoracic radiotherapy within a median time of <2 years. The present findings provide further evidence to support significant associations between TotalLeft radiotherapy dose and cardiac events and define CAC as a predictive risk factor.

Abstract OT3-09-04: A randomized phase II study comparing surgical excision versus NeOadjuvant Radiotherapy followed by delayed surgical excision of Ductal carcinoma In Situ (NORDIS)

A randomized phase II study comparing surgical excision versus NeOadjuvant Radiotherapy followed by delayed surgical excision of Ductal carcinoma In Situ (NORDIS)

Breast radiotherapy (RT) for DCIS has been studied only in the adjuvant setting, following lumpectomy surgery. Adjuvant RT reduced invasive recurrences by 52% in the combined analysis of the two largest DCIS trials NSABP B-17/B-24, and reduced recurrences even for low or intermediate grade DCIS in the RTOG 9804 trial (recurrence 0.9% with RT versus 6.7% without RT). The mechanism of action is hypothesized to be elimination of occult disease and/or inhibition of neoplastic transformation in normal breast tissue.

Trial Design To understand the ablative effects of RT on pure DCIS, we are conducting a prospective randomized trial comparing histopathological findings of surgical excision (Arm 1) to neoadjuvant partial breast irradiation (neoRT) followed by delayed surgical excision (Arm 2) for patients with core needle biopsy proven DCIS. Arm 1 will provide a reference group for upstaging to invasive cancer, molecular markers and pathological-radiological correlations. Arm 2 participants will receive 6 Gy daily x 5 to the intact tumor with a 0.5 cm margin of normal tissue. Surgical excision will be delayed 12-16 weeks to allow for the radioablative effects to occur and radiation-induced inflammation to subside.

Specific Aims To determine if neoRT can completely ablate at least 30% of pure DCISTo determine if DCIS subtypes exhibit differential sensitivity to neoRTTo determine the radiation-induced treatment effects; wound complication rates; radiological

Eligibility Women 18 years of age or older with DCIS diagnosed on vacuum assisted core needle biopsy who intend to receive breast conserving surgery are eligible, excluding those with a prior history of ipsilateral breast cancer. The imaging abnormality must be mammographic microcalcifications and/or MRI non-mass enhancement measuring &lt;3 cm and not completely removed by core needle biopsy.

Statistics A total of 50 patients will be recruited. Upstaging to invasive cancer is anticipated to be approximately 10% in the reference group. With 25 subjects in each arm, we will have 80% power to detect a 30% or higher improvement in the DCIS complete response rate following neoRT.

Accrual Opened to accrual June 1, 2019

Contact wapnir@stanford.edu

Wapnir IL, Dignam JJ, Fisher B, et al. Long-term outcomes of invasive ipsilateral breast tumor recurrences after lumpectomy in NSABP B-17 and B-24 randomized clinical trials for DCIS. J Natl Cancer Inst. 2011;103(6):478-488. doi:10.1093/jnci/djr027.

McCormick B, Winter K, Hudis C, et al. RTOG 9804: a prospective randomized trial for good-risk ductal carcinoma in situ comparing radiotherapy with observation. J Clin Oncol. 2015;33(7):709-715. doi:10.1200/JCO.2014.57.9029.

Citation Format: Irene Wapnir, Wendy DeMartini, Kimberly Allison, Kimberly Stone, Frederick Dirbas, Carol Marquez, Debra Ikeda, Sunita Pal, Jacqueline Tsai, Rachel Yang, Robert West, Alex McMillan, Melinda Telli, Kathleen Horst. A randomized phase II study comparing surgical excision versus NeOadjuvant Radiotherapy followed by delayed surgical excision of Ductal carcinoma In Situ (NORDIS) [abstract]. In: Proceedings of the 2019 San Antonio Breast Cancer Symposium; 2019 Dec 10-14; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2020;80(4 Suppl):Abstract nr OT3-09-04.

Predictors of Atrial Fibrillation After Thoracic Radiotherapy

Background

Atrial fibrillation (AF) has been associated with thoracic radiotherapy, but the specific risk with irradiating different cardiac substructures remains unknown.

Objectives

This study sought to examine the relationship between irradiation of cardiac substructures and the risk of clinically significant (grade ≥3) AF.

Methods

We analyzed data from patients who underwent definitive radiotherapy for localized cancers (non-small cell lung, breast, Hodgkin lymphoma, or esophageal) at our institution between 2004 and 2022. The 2-Gy fraction equivalent dose was calculated for cardiac substructures, including the pulmonary veins (PVs), left atrium, sinoatrial node, and left coronary arteries (the left main, left anterior descending, and left circumflex arteries). Competing risk models (subdistribution HRs [sHRs]) for AF incidence were adjusted for the Mayo AF risk score (MAFRS).

Results

Among 539 patients, the median follow-up was 58.8 months. The 5-year cumulative incidence of AF was 11.1% for non-small cell lung cancer, 8.3% for esophageal cancer, 1.3% for breast cancer, and 0.8% for Hodgkin lymphoma. Increased AF risk was associated with a higher PV maximum dose (dmax) (sHR: 1.22; P < 0.001), larger left atrial volume (sHR: 1.01; P = 0.002), greater smoking history in pack-years (sHR: 1.01; P = 0.010), and higher MAFRS (sHR: 1.16; P < 0.001). PV dmax remained a significant predictor of AF across different MAFRS subgroups (P interaction = 0.11), and a PV dmax >39.7 Gy was linked to a higher AF risk, even when stratified by MAFRS.

Conclusions

PV dmax is a significant predictor of grade ≥3 AF regardless of underlying risk factors. These findings highlight the importance of cardiac substructures in radiation toxicity and suggest that various PV dose metrics should be further validated in clinical settings.

Abstract P4-16-11: Impact of receptor status on prognosis among breast cancer patients with brain metastases treated with Cyberknife radiosurgery

Purpose: Stereotactic radiosurgery (SRS) is increasingly used in the management of brain metastases. Receptor status is an important prognostic factor among women with breast cancer. The aim of this study was to evaluate the effect of receptor status on clinical outcomes in breast cancer patients with brain metastases treated with SRS.

Materials and Methods: We performed a retrospective review of 102 primary breast cancer patients with brain metastases treated with Cyberknife radiosurgery at Stanford University Medical Center between 2004 and 2011. The clinical characteristics, pathologic features, treatment details and clinical outcomes were reviewed. Median follow-up time was 18 months from the date of treatment with Cyberknife radiosurgery. All analyses were performed using SAS software, version 9.3 (SAS Institute, Cary, NC).

Results: Patients with Her-2/neu positive receptor status treated with trastuzumab had a significantly improved median overall survival after treatment with stereotactic radiosurgery compared to patients with Her-2/neu negative receptor status (27 months vs 7 months, p = 0.002) or patients with Her-2/neu positive receptor status who did not receive trastuzumab (27 months vs 12 months, p = 0.04). In contrast, patients with estrogen receptor, progesterone receptor and Her-2/neu negative receptor status had significantly worse median overall survival after treatment with stereotactic radiosurgery compared to patients with at least one positive receptor (8 months vs 17 months, p = 0.02). On multivariable analysis, Her-2/neu status emerged as the only significant predictor of survival (p = 0.01).

Conclusions: Her-2/neu receptor status was found to be a significant prognostic factor influencing survival among breast cancer patients with brain metastases treated with SRS. Importantly, the addition of treatment with trastuzumab among Her-2 neu positive patients significantly improved clinical outcomes.

Citation Information: Cancer Res 2012;72(24 Suppl):Abstract nr P4-16-11.