Patterns in the Reporting of Aggressive Histologic Subtypes in Papillary Thyroid Cancer

INTRODUCTION

The tall cell, columnar, and diffuse sclerosing subtypes are aggressive histologic subtypes of papillary thyroid cancer (PTC) with increasing incidence, yet there is a wide variation in reporting. We aimed to identify and compare factors associated with the reporting of these aggressive subtypes (aPTC) to classic PTC (cPTC) and secondarily identify differences in outcomes.

METHODS

The National Cancer Database was utilized to identify cPTC and aPTC from 2004 to 2017. Patient and facility demographics and clinicopathologic variables were analyzed. Independent predictors of aPTC reporting were identified and a survival analysis was performed.

RESULTS

The majority of aPTC (67%) were reported by academic facilities. Compared to academic facilities, all other facility types were 1.4-2.0 times less likely to report aPTC (P < 0.05). Regional variation in reporting was noted, with more cases reported in the Middle Atlantic, despite there being more total facilities in the South Atlantic and East North Central regions. Compared to the Middle Atlantic, all other regions were 1.4-5 times less likely to report aPTC (P < 0.001). Patient characteristics including race and income were not associated with aPTC reporting. Compared to cPTC, aPTC had higher rates of aggressive features and worse 5-y overall survival (90.5% versus 94.5%, log rank P < 0.001).

CONCLUSIONS

Aggressive subtypes of PTC are associated with worse outcomes. Academic and other facilities in the Middle Atlantic were more likely to report aPTC. This suggests the need for further evaluation of environmental or geographic factors versus a need for increased awareness and more accurate diagnosis of these subtypes.

Low Mitotic Activity in Papillary Thyroid Cancer: A Marker for Aggressive Features and Recurrence

CONTEXT

The significance of low mitotic activity in papillary thyroid cancer (PTC) is largely undefined.

OBJECTIVE

We aimed to determine the behavioral landscape of PTC with low mitotic activity compared to that of no- and high-mitotic activity.

METHODS

A single-institution consecutive series of PTC patients from 2018-2022 was reviewed. Mitotic activity was defined as no mitoses, low (1-2 mitoses/2 mm2) or high (≥3 mitoses/2 mm2) per the World Health Organization. The 2015 American Thyroid Association risk stratification was applied to the cohort, and clinicopathologic features were compared between groups. For patients with ≥6 months follow-up, Cox regression analyses for recurrence were performed.

RESULTS

640 PTCs were included - 515 (80.5%) no mitotic activity, 110 (17.2%) low mitotic activity, and 15 (2.3%) high mitotic activity. Overall, low mitotic activity exhibited rates of clinicopathologic features including vascular invasion, gross extrathyroidal extension, and lymph node metastases in between those of no- and high-mitotic activity. PTCs with low mitotic activity had higher rates of intermediate- and high-risk ATA risk stratification compared to those with no mitotic activity (p < 0.001). Low mitotic activity PTCs also had higher recurrence rates (15.5% vs. 4.5%, p < 0.001). Low mitotic activity was associated with recurrence, independent of the ATA risk stratification (HR 2.96; 95% CI 1.28-6.87, p = 0.01).

CONCLUSIONS

Low mitotic activity is relatively common in PTC and its behavior lies within a spectrum between no- and high-mitotic activity. Given its association with aggressive clinicopathologic features and recurrence, low mitotic activity should be considered when risk stratifying PTC patients for recurrence.

Timing to Surgery and Lymph Node Upstaging in Gastric Cancer: An NCDB Analysis

BACKGROUND

Prior studies have shown tumor specificity on the impact of longer time interval from diagnosis to surgery, however in gastric cancer (GC) this remains unclear. We aimed to determine if a longer time interval from diagnosis to surgery had an impact on lymph node (LN) upstaging and overall survival (OS) outcomes among patients with clinically node negative (cN0) GC.

PATIENTS AND METHODS

Patients diagnosed with cN0 GC undergoing surgery between 2004-2018 were identified in the National Cancer Database (NCDB) and divided into intervals between time of diagnosis and surgery [short interval (SI): ≥ 4 days to < 8 weeks and long interval (LI): ≥ 8 weeks]. Multivariable regression analysis evaluated the independent impact of surgical timing on LN upstaging and a Cox proportional hazards analysis and Kaplan-Meier curves evaluated survival outcomes.

RESULTS

Of 1824 patients with cN0 GC, 71.8% had a SI to surgery and 28.1% had a LI to surgery. LN upstaging was seen more often in the SI group when compared to LI group (82% versus 76%, p = 0.004). LI to surgery showed to be an independent factor protective against LN upstaging [adjusted odds ratio = 0.62, 95% CI: (0.39-0.99)]. Multivariate Cox regression analysis indicated that time to surgery was not associated with a difference in overall survival [hazard ratio (HR) = 0.91, 95% CI: (0.71-1.17)], however uncontrolled Kaplan-Meier curves showed OS difference between the SI and LI to surgery groups (p = 0.037).

CONCLUSION

Timing to surgery was not a predictor of LN upstaging or overall survival, suggesting that additional medical optimization in preparation for surgery and careful preoperative staging may be appropriate in patients with node negative early stage GC without affecting outcomes.

Impedance planimetry (EndoFLIPTM) and surgical outcomes after Hill compared to Toupet fundoplication

INTRODUCTION

Endoluminal functional lumen imaging probe (EndoFLIP) provides a real-time assessment of gastroesophageal junction (GEJ) compliance during fundoplication. Given the limited data on EndoFLIP measurements during the Hill procedure, we investigated the impact of the Hill procedure on GEJ compliance compared to Toupet fundoplication.

METHODS

Patients who underwent robotic Hill or Toupet fundoplication with intraoperative EndoFLIP between 2017 and 2022 were included. EndoFLIP measurements of the GEJ included cross sectional surface area (CSA), intra-balloon pressure, high pressure zone length (HPZ), distensibility index (DI), and compliance. Subjective reflux symptoms, gastroesophageal reflux disease-health related quality of life (GERD-HRQL) score, and dysphagia score were assessed pre-operatively as well as at short- and longer-term follow-up.

RESULTS

One-hundred and fifty-four patients (71.9%) had a Toupet fundoplication while sixty (28%) patients underwent the Hill procedure. The CSA [27.7 ± 10.9 mm2 vs 42.2 ± 17.8 mm2, p < 0.0001], pressure [29.5 ± 6.2 mmHg vs 33.9 ± 8.5 mmHg, p = 0.0009], DI [0.9 ± 0.4 mm2/mmHg vs 1.3 ± 0.6 mm2/mmHg, p = 0.001], and compliance [25.9 ± 12.8 mm3/mmHg vs 35.4 ± 13.4 mm3/mmHg, p = 0.01] were lower after the Hill procedure compared to Toupet. However, there was no difference in post-fundoplication HPZ between procedures [Hill: 2.9 ± 0.4 cm, Toupet: 3.1 ± 0.6 cm, p = 0.15]. Follow-up showed no significant differences in GERD-HRQL scores, overall dysphagia scores or atypical symptoms between groups (p > 0.05).

CONCLUSION

The Hill procedure is as effective to the Toupet fundoplication in surgically treating gastroesophageal reflux disease (GERD) despite the lower CSA, DI, and compliance after the Hill procedure. Both procedures led to DI < 2 mm2/mmHg with no significant differences in dysphagia reporting (12-24) months after the procedure. Further studies to elucidate a cutoff value for DI for postoperative dysphagia development are still warranted.

Clinical utility of a microRNA classifier in cytologically indeterminate thyroid nodules with RAS mutations: A multi-institutional study

BACKGROUND

Molecular testing guides the management of cytologically indeterminate thyroid nodules. We evaluated the real-world clinical benefit of a commercially available thyroid mutation panel plus microRNA risk classifier in classifying RAS-mutated nodules.

METHODS

We performed a subgroup analysis of the results of molecular testing of Bethesda III/IV nodules using the ThyGenX/ThyGeNEXT-ThyraMIR platform at 3 tertiary-care centers between 2017 and 2021, defining a positive result as 10% or greater risk of malignancy.

RESULTS

We identified 387 nodules from 375 patients (70.7% female, median age 59.3 years) who underwent testing. Positive nodules (32.3%) were associated with increased surgical intervention (74.4% vs 14.9%, P < .0001) and carcinoma on surgical pathology (46.4% vs 3.4%, P < .0001) compared to negative modules. RAS mutations were the most common mutations, identified in 71 of 380 (18.7%) nodules, and were classified as ThyraMIR- (28 of 71; 39.4%) or ThyraMIR+ (43 of 71; 60.6%). Among RAS-mutated nodules, there was no significant difference in operative rate (P = .2212) or carcinoma diagnosis (P = .6277) between the ThyraMIR+ and ThyraMIR- groups, and the sensitivity, specificity, negative predictive value, and positive predictive value of ThyraMIR were 64.7%, 34.8%, 40.0%, and 59.5%, respectively.

CONCLUSION

Although testing positive is associated with malignancy in surgical pathology, the ThyraMIR classifier failed to differentiate between benign and malignant RAS-mutated nodules. Diagnostic lobectomy should be considered for RAS-mutated nodules, regardless of microRNA expression status.

Radioactive iodine administration is not associated with improved disease-specific survival in classic papillary thyroid carcinoma greater than 4 cm confined to the thyroid

BACKGROUND

We aimed to evaluate the impact of radioactive iodine on disease-specific survival in intrathyroidal (N0M0) papillary thyroid carcinoma >4 cm, given conflicting data in the American Thyroid Association guidelines regarding their management.

METHODS

The Surveillance, Epidemiology, and End Results database was queried for N0M0 classic papillary thyroid carcinoma >4 cm. Kaplan-Meier estimates were performed to compare disease-specific survival between radioactive iodine-treated and untreated groups. A multivariable Cox regression was performed to identify predictors of disease-specific survival.

RESULTS

There were more patients aged ≥55 (41.7% vs 32.3%, P = .001) and fewer multifocal tumors (25.3% vs 30.6%, P = .006) in the no radioactive iodine group. Ten-year disease-specific survival was similar between the radioactive iodine treated and untreated groups (97.2% vs 95.6%, P = .34). Radioactive iodine was not associated with a significant disease-specific survival benefit (adjusted hazard ratio = 0.78, confidence interval [0.39-1.58], P = .49). Age ≥55 (adjusted hazard ratio = 3.50, confidence interval [1.69-7.26], P = .001) and larger tumor size (adjusted hazard ratio = 1.04, confidence interval [1.02-1.06], P < .001) were associated with an increased risk of disease-specific death. Subgroup analyses did not demonstrate improved disease-specific survival with radioactive iodine in patients ≥55 and in tumors >5 cm.

CONCLUSION

Adjuvant radioactive iodine administration in classic papillary thyroid carcinoma >4 cm confined to the thyroid did not significantly impact disease-specific survival. Thus, these patients may not require routine treatment with adjuvant radioactive iodine.

Gastric development of pancreatic acinar cell metaplasia after Vonoprazan therapy in rats

BACKGROUND

Vonoprazan is a new acid-suppressing drug that received FDA approval in 2022. It reversibly inhibits gastric acid secretion by competing with the potassium ions on the luminal surface of the parietal cells (potassium-competitive acid blockers or P-CABs). Vonoprazan has been on the market for a short time and there are many clinical trials to support its clinical application. However, medical experience and comprehensive clinical data is still limited, especially on how and if, gastric histology is altered due to therapy.

METHODS

A 12-week experiment trial with 30 Wistar rats was to assess the presence of gastrointestinal morphologic abnormalities upon administration of omeprazole and vonoprazan. At six weeks of age, rats were randomly assigned to one of 5 groups: (1) saline as negative control group, (2) oral omeprazole (40 mg/kg), as positive control group, (3) oral omeprazole (40 mg/kg) for 4 weeks, proceeded by 8 weeks off omeprazole, (4) oral vonoprazan (4 mg/kg), as positive control group, and (5) oral vonoprazan (4 mg/kg) for 4 weeks, proceeded by 8 weeks off vonoprazan.

RESULTS

We identified non-inflammatory alterations characterized by parietal (oxyntic) cell loss and chief (zymogen) cell hyperplasia and replacement by pancreatic acinar cell metaplasia (PACM). No significant abnormalities were identified in any other tissues in the hepatobiliary and gastrointestinal tracts.

CONCLUSION

PACM has been reported in gastric mucosa, at the esophagogastric junction, at the distal esophagus, and in Barrett esophagus. However, the pathogenesis of this entity is still unclear. Whereas some authors have suggested that PACM is an acquired process others have raised the possibility of PACM being congenital in nature. Our results suggest that the duration of vonoprazan administration at a dose of 4 mg/kg plays an important role in the development of PACM.

Treatment of Secondary Hyperparathyroidism and Posttransplant Tertiary Hyperparathyroidism

INTRODUCTION

Secondary hyperparathyroidism (sHPT) is prevalent in dialysis patients and can lead to tertiary hyperparathyroidism (tHPT) after kidney transplantation. We aimed to assess the association of pretransplant sHPT treatment on posttransplant outcomes.

METHODS

We reviewed kidney transplant patients treated with parathyroidectomy or cinacalcet for sHPT. We compared patients biochemical and clinical parameters, and outcomes based on sHPT treatment.

RESULTS

A total of 41 patients were included: 18 patients underwent parathyroidectomy and 23 patients received cinacalcet prior to transplantation. There were no significant differences between demographics, comorbidities, allograft characteristics or pre-sHPT intervention parathyroid hormone (PTH) and calcium levels. Patients that underwent parathyroidectomy were on dialysis for longer, although not significantly (71.9 versus 42.3 mo, P = 0.051). At time of transplantation, patients treated by parathyroidectomy had increased rates of controlled sHPT (88.9%; 16/18 versus 47.8%; 11/23, P = 0.008). Patients treated by parathyroidectomy had decreased development of tHPT (5.9%; 1/17; versus 42.1%; 8/19, P = 0.020) as well as decreased rates of posttransplant treatment with cinacalcet (11.1%; 2/18 versus 52.2%; 12/23, P = 0.008). Three patients treated with cinacalcet underwent parathyroidectomy after transplantation. Median PTH after transplant remained lower in patients treated by parathyroidectomy prior to transplant compared to those treated with cinacalcet (60.7 [interquartile range 39.7-133.4] versus 170.0 [interquartile range 128.4-292.7], P = 0.001). Allograft function and survival were similar for parathyroidectomy and cinacalcet, with median follow-up after transplantation of 56.7 and 34.2 mo, respectively.

CONCLUSIONS

sHPT treated by parathyroidectomy is associated with controlled PTH levels at transplantation and decreased rates of tHPT. Long-term outcomes should be studied on a larger scale.

Long-term potassium-competitive acid blockers administration causes microbiota changes in rats

BACKGROUND

Vonoprazan is a new potassium-competitive acid blocker (P-CAB) that was recently approved by the FDA. It is associated with a fast onset of action and a longer acid inhibition time. Vonoprazan-containing therapy for helicobacter pylori eradication is highly effective and several studies have demonstrated that a vonoprazan-antibiotic regimen affects gut microbiota. However, the impact of vonoprazan alone on gut microbiota is still unclear.Please check and confirm the authors (Maria Cristina Riascos, Hala Al Asadi) given name and family name are correct. Also, kindly confirm the details in the metadata are correct.Yes they are correct.  METHODS: We conducted a prospective randomized 12-week experimental trial with 18 Wistar rats. Rats were randomly assigned to one of 3 groups: (1) drinking water as negative control group, (2) oral vonoprazan (4 mg/kg) for 12 weeks, and (3) oral vonoprazan (4 mg/kg) for 4 weeks, followed by 8 weeks off vonoprazan. To investigate gut microbiota, we carried out a metagenomic shotgun sequencing of fecal samples at week 0 and week 12.Please confirm the inserted city and country name is correct for affiliation 2.Yes it's correct.

RESULTS

For alpha diversity metrics at week 12, both long and short vonoprazan groups had lower Pielou's evenness index than the control group (p = 0.019); however, observed operational taxonomic units (p = 0.332) and Shannon's diversity index (p = 0.070) were not statistically different between groups. Beta diversity was significantly different in the three groups, using Bray-Curtis (p = 0.003) and Jaccard distances (p = 0.002). At week 12, differences in relative abundance were observed at all levels. At phylum level, short vonoprazan group had less of Actinobacteria (log fold change = - 1.88, adjusted p-value = 0.048) and Verrucomicrobia (lfc = - 1.76, p = 0.009).Please check and confirm that the author (Ileana Miranda) and their respective affiliation 3 details have been correctly identified and amend if necessary.Yes it's correct. At the genus level, long vonoprazan group had more Bacteroidales (lfc = 5.01, p = 0.021) and Prevotella (lfc = 7.79, p = 0.001). At family level, long vonoprazan group had more Lactobacillaceae (lfc = 0.97, p = 0.001), Prevotellaceae (lfc = 8.01, p < 0.001), and less Erysipelotrichaceae (lfc = - 2.9, p = 0.029).

CONCLUSION

This study provides evidence that vonoprazan impacts the gut microbiota and permits a precise delineation of the composition and relative abundance of the bacteria at all different taxonomic levels.

An Original Study: Is There an Optimal Time to Complete Dedicated Research During Surgical Residency? Twelve Years of Research Experience After PGY2 or PGY3

OBJECTIVE

We aimed to determine if there is an optimal time to complete dedicated research during surgical residency.

BACKGROUND

Research is an integral part of academic general surgical residency, and dedicated research usually occurs after the 2nd or 3rd post-graduate year (PGY). The timing of dedicated research and its association with resident productivity, self-assessed competency (including technical skills), and fellowship match is not known.

METHODS

PubMed was queried for publications resulting after dedicated research time for graduating surgical residents at a single institution from 2010 to 2021. Graduates were surveyed about their research experience and placed into 2 groups: research after PGY2 or PGY3.

RESULTS

Sixty-six of 91 (73%) graduating residents completed dedicated research (after PGY2, n=28; after PGY3, n=38). Median number of total and first author publications was similar between groups; however, research after PGY2 was associated with an increased number of basic science publications by fellowship application deadlines (PGY2: 1.0[0-13] vs PGY3: 0.0[0-6], p=0.02). With a 79% survey response rate, there were no differences in self-assessed competencies upon return from research between cohorts. Most surveyed residents matched at their top fellowship choice (PGY2:70% vs PGY3:62%, p=0.77).

CONCLUSIONS

Research after PGY2 or PGY3 had no association with residents' total number of publications, self-assessed competency, or rates of matching at first choice fellowship. As research after PGY2 had an increased number of basic science publications by time of fellowship application, surgical residents applying to fellowships that highly value basic science research may benefit from completing dedicated research after PGY2.

Activation of the JAK/STAT Pathway Leads to BRAF Inhibitor Resistance in BRAFV600E Positive Thyroid Carcinoma

A subset of thyroid cancers, recurrent differentiated thyroid cancers and anaplastic thyroid cancer (ATC), are difficult to treat by thyroidectomy and systemic therapy. A common mutation in thyroid cancer, BRAFV600E, has targetable treatment options; however, the results have been disappointing in thyroid cancers compared with BRAFV600E melanoma, as thyroid cancers quickly become resistant to BRAFV600E inhibitor (BRAFi). Here, we studied the molecular pathway that is induced in BRAFV600E thyroid cancer cells and patient-derived tumor samples in response to BRAFi, vemurafenib, using RNA-sequencing and molecular analysis. Both inducible response to BRAFi and acquired BRAFi resistance in BRAFV600E thyroid cancer cells showed significant activation of the JAK/STAT pathway. Functional analyses revealed that the combination of BRAFi and inhibitors of JAK/STAT pathway controlled BRAFV600E thyroid cancer cell growth. The Cancer Genome Atlas data analysis demonstrated that potent activation of the JAK/STAT signaling was associated with shorter recurrence rate in patients with differentiated thyroid cancer. Analysis of tumor RNA expression in patients with poorly differentiated thyroid cancer and ATC also support that enhanced activity of JAK/STAT signaling pathway is correlated with worse prognosis. Our study demonstrates that JAK/STAT pathway is activated as BRAFV600E thyroid cancer cells develop resistance to BRAFi and that this pathway is a potential target for anticancer activity and to overcome drug resistance that commonly develops to treatment with BRAFi in thyroid cancer.

IMPLICATIONS

Dual inhibition of BRAF and JAK/STAT signaling pathway is a potential therapeutic treatment for anticancer activity and to overcome drug resistance to BRAFi in thyroid cancer.

Perineural Invasion in Papillary Thyroid Cancer: A Rare Indicator of Aggressive Disease

BACKGROUND

Perineural invasion (PNI) is associated with aggressive tumor behavior, increased locoregional recurrence, and decreased survival in many carcinomas. However, the significance of PNI in papillary thyroid cancer (PTC) is incompletely characterized.

METHODS

Patients diagnosed with PTC and PNI from 2010-2020 at a single, academic center were identified and matched using a 1:2 scheme to patients without PNI based on gross extrathyroidal extension (ETE), nodal metastasis, positive margins, and tumor size (±4 cm). Mixed and fixed effects models were used to analyze the association of PNI with extranodal extension (ENE)-a surrogate marker of poor prognosis.

RESULTS

In total, 78 patients were included (26 with PNI, 52 without PNI). Both groups had similar demographics and ultrasound characteristics preoperatively. Central compartment lymph node dissection was performed in most patients (71%, n = 55), and 31% (n = 24) underwent a lateral neck dissection. Patients with PNI had higher rates of lymphovascular invasion (50.0% vs. 25.0%, p = 0.027), microscopic ETE (80.8% vs. 44.0%, p = 0.002), and a larger burden [median 5 (interquartile range [IQR] 2-13) vs. 2 (1-5), p = 0.010] and size [median 1.2 cm (IQR 0.6-2.6) vs. 0.4 (0.2-1.4), p = 0.008] of nodal metastasis. Among patients with nodal metastasis, those with PNI had an almost fivefold increase in ENE [odds ratio [OR] 4.9 (95% confidence interval [CI] 1.5-16.5), p = 0.008] compared with those without PNI. More than a quarter (26%) of all patients had either persistent or recurrent disease over follow-up (IQR 16-54 months).

CONCLUSIONS

PNI is a rare, pathologic finding that is associated with ENE in a matched cohort. Additional investigation into PNI as a prognostic feature in PTC is warranted.

Limited disease progression in endocrine surgery patients with treatment delays due to COVID-19

BACKGROUND

The COVID-19 pandemic profoundly impacted the delivery of care and timing of elective surgical procedures. Most endocrine-related operations were considered elective and safe to postpone, providing a unique opportunity to assess clinical outcomes under protracted treatment plans.

METHODS

American Association of Endocrine Surgeon members were surveyed for participation. A Research Electronic Data Capture survey was developed and distributed to 27 institutions to assess the impact of COVID-19-related delays. The information collected included patient demographics, primary diagnosis, resumption of care, and assessment of disease progression by the surgeon.

RESULTS

Twelve out of 27 institutions completed the survey (44.4%). Of 850 patients, 74.8% (636) were female; median age was 56 (interquartile range, 44-66) years. Forty percent (34) of patients had not been seen since their original surgical appointment was delayed; 86.2% (733) of patients had a delay in care with women more likely to have a delay (87.6% vs 82.2% of men, χ² = 3.84, P = .05). Median duration of delay was 70 (interquartile range, 42-118) days. Among patients with a delay in care, primary disease site included thyroid (54.2%), parathyroid (37.2%), adrenal (6.5%), and pancreatic/gastrointestinal neuroendocrine tumors (1.3%). In addition, 4.0% (26) of patients experienced disease progression and 4.1% (24) had a change from the initial operative plan. The duration of delay was not associated with disease progression (P = .96) or a change in operative plan (P = .66).

CONCLUSION

Although some patients experienced disease progression during COVID-19 delays to endocrine disease-related care, most patients with follow-up did not. Our analysis indicated that temporary delay may be an acceptable course of action in extreme circumstances for most endocrine-related surgical disease.

Metastatic pancreatic neuroendocrine tumors feature elevated T cell infiltration

Pancreatic neuroendocrine tumors (PNETs) are malignancies arising from the islets of Langerhans. Therapeutic options are limited for the over 50% of patients who present with metastatic disease. We aimed to identify mechanisms to remodel the PNET tumor microenvironment (TME) to ultimately enhance susceptibility to immunotherapy. The TMEs of localized and metastatic PNETs were investigated using an approach that combines RNA-Seq, cancer and T cell profiling, and pharmacologic perturbations. RNA-Seq analysis indicated that the primary tumors of metastatic PNETs showed significant activation of inflammatory and immune-related pathways. We determined that metastatic PNETs featured increased numbers of tumor-infiltrating T cells compared with localized tumors. T cells isolated from both localized and metastatic PNETs showed evidence of recruitment and antigen-dependent activation, suggestive of an immune-permissive microenvironment. A computational analysis suggested that vorinostat, a histone deacetylase inhibitor, may perturb the transcriptomic signature of metastatic PNETs. Treatment of PNET cell lines with vorinostat increased chemokine CCR5 expression by NF-κB activation. Vorinostat treatment of patient-derived metastatic PNET tissues augmented recruitment of autologous T cells, and this augmentation was substantiated in a mouse model of PNET. Pharmacologic induction of chemokine expression may represent a promising approach for enhancing the immunogenicity of metastatic PNET TMEs.

Care Fragmentation in Patients with Differentiated Thyroid Cancer

BACKGROUND

Among surgical patients, care fragmentation (CF) is associated with worse outcomes. However, oncologic literature documents an association between high surgical volume and improved outcomes, favoring centralized cancer-surgery centers and thus predisposing to CF in patients with surgically treated tumors. We aimed to identify features associated with CF and ascertain differences in overall survival (OS) among patients with differentiated thyroid cancer (DTC).

METHODS

The National Cancer Database was queried for DTC patients diagnosed from 2009 to 2017. Patients experienced CF if part of their treatment was performed outside of the reporting facility or an associated office. A multivariable logistic regression analysis identified independent features associated with CF. A Cox multivariable regression analysis assessed the impact of CF on OS. A Kaplan-Meier analysis compared survival differences between patients experiencing CF or unified care (UC).

RESULTS

A total of 131,620 patients were included. Among them, 70,204 (53.3%) experienced CF and 61,416 (46.7%) experienced UC. Age < 55, residing in high-income areas, and stage 3 and 4 tumors were features independently associated with CF, whereas uninsured patients were less likely to experience CF than the privately insured. The features most strongly associated with CF were treatment at highest thyroid cancer-surgery volume institutions and traveling in the top distance quartile. While patients with CF experienced minor delays in time from diagnosis to surgery, 5-year OS was improved among patients with CF compared to UC for those with Stage 1-3 disease.

CONCLUSIONS

Among patients with DTC, CF is associated with treatment at a highest thyroid cancer surgery volume facility and improved OS in a setting of minor treatment delays.

Metagenomic Sequencing of the Gallbladder Microbiome: Bacterial Diversity Does Not Vary by Surgical Pathology

INTRODUCTION

Alterations in the microbiome contribute to the pathogenesis of many gastrointestinal diseases. However, the composition of the microbiome in gallbladder disease is not well described.

METHODS

We aimed to characterize the biliary microbiome in cholecystectomy patients. Bile and biliary stones were collected at cholecystectomy for a variety of surgical indications between 2017 and 2019. DNA was extracted and metagenomic sequencing was performed with subsequent taxonomic classification using Kraken2. The fraction of bacterial to total DNA reads, relative abundance of bacterial species, and overall species diversity were compared between pathologies and demographics.

RESULTS

A total of 74 samples were obtained from 49 patients: 46 bile and 28 stones, with matched pairs from 25 patients. The mean age was 48 years, 76% were female, 29% were Hispanic, and 29% of patients had acute cholecystitis. The most abundant species were Klebsiella pneumoniae, Staphylococcus aureus, and Streptococcus pasteurianus. The bacterial fraction in bile and stone samples was higher in acute cholecystitis compared to other non-infectious pathologies (p < 0.05). Neither the diversity nor differential prevalence of specific bacterial species varied significantly between infectious and other non-infectious gallbladder pathologies. Multivariate analysis of the non-infectious group revealed that patients over 40 years of age had increased bacterial fractions (p < 0.05).

CONCLUSIONS

Metagenomic sequencing permits characterization of the gallbladder microbiome in cholecystectomy patients. Although a higher prevalence of bacteria was seen in acute cholecystitis, species and diversity were similar regardless of surgical indication. Additional study is required to determine how the microbiome can contribute to the development of symptomatic gallbladder disease.

Comparative Outcomes of Anti-Reflux Surgery in Obese Patients with Gastroesophageal Reflux Disease1

INTRODUCTION

Roux-en-Y gastric bypass (RYGB) has been the preferred operation for obese patients with gastroesophageal reflux disease (GERD); however, some patients are hesitant to undergo bypass. Obese patients have a multifactorial predisposition to GERD, including lower esophageal sphincter (LES) dysfunction and aberrant pressure gradients across their diaphragmatic crura. Among non-obese patients, anti-reflux surgery (ARS) with hiatal hernia (HH) repair and LES augmentation has shown excellent long-term results. We aimed to determine whether patient satisfaction and GERD recurrence differed between obese and non-obese patients who underwent ARS.

METHODS

Review of patients who underwent ARS between January 2012 and June 2021 was performed. Perioperative and postoperative characteristics were compared across three BMI groups: BMI < 30 kg/m², 30 kg/m² ≤ BMI < 35 kg/m², and BMI ≥ 35 kg/m².

RESULTS

Four-hundred thirteen patients were identified, of which 294 (71.1%) had BMI < 30 kg/m², 87 (21.1%) were 30 kg/m² ≤ BMI < 35 kg/m², and 32 (7.7%) had a BMI ≥ 35 kg/m². Patients with BMI ≥ 35 kg/m² had higher preoperative manometric and EndoFLIP™ intra-balloon pressure at the LES than those with lower BMIs. This value was increased to a similar level throughout ARS across the three cohorts. Post-operative GERD-specific satisfaction was similar across the three cohorts, as were rates of postoperative reflux and hiatal hernia recurrence on barium swallow; rates of reoperation were low.

CONCLUSIONS

ARS with HH repair and LES augmentation may be appropriate for select patients across a range of BMIs, including those with a BMI ≥ 35 kg/m² who are hesitant to undergo RYGB.

American Association of Endocrine Surgeons Guidelines for Adrenalectomy: Executive Summary

Importance

Adrenalectomy is the definitive treatment for multiple adrenal abnormalities. Advances in technology and genomics and an improved understanding of adrenal pathophysiology have altered operative techniques and indications.

Objective

To develop evidence-based recommendations to enhance the appropriate, safe, and effective approaches to adrenalectomy.

Evidence Review

A multidisciplinary panel identified and investigated 7 categories of relevant clinical concern to practicing surgeons. Questions were structured in the framework Population, Intervention/Exposure, Comparison, and Outcome, and a guided review of medical literature from PubMed and/or Embase from 1980 to 2021 was performed. Recommendations were developed using Grading of Recommendations, Assessment, Development and Evaluation methodology and were discussed until consensus, and patient advocacy representation was included.

Findings

Patients with an adrenal incidentaloma 1 cm or larger should undergo biochemical testing and further imaging characterization. Adrenal protocol computed tomography (CT) should be used to stratify malignancy risk and concern for pheochromocytoma. Routine scheduled follow-up of a nonfunctional adrenal nodule with benign imaging characteristics and unenhanced CT with Hounsfield units less than 10 is not suggested. When unilateral disease is present, laparoscopic adrenalectomy is recommended for patients with primary aldosteronism or autonomous cortisol secretion. Patients with clinical and radiographic findings consistent with adrenocortical carcinoma should be treated at high-volume multidisciplinary centers to optimize outcomes, including, when possible, a complete R0 resection without tumor disruption, which may require en bloc radical resection. Selective or nonselective α blockade can be used to safely prepare patients for surgical resection of paraganglioma/pheochromocytoma. Empirical perioperative glucocorticoid replacement therapy is indicated for patients with overt Cushing syndrome, but for patients with mild autonomous cortisol secretion, postoperative day 1 morning cortisol or cosyntropin stimulation testing can be used to determine the need for glucocorticoid replacement therapy. When patient and tumor variables are appropriate, we recommend minimally invasive adrenalectomy over open adrenalectomy because of improved perioperative morbidity. Minimally invasive adrenalectomy can be achieved either via a retroperitoneal or transperitoneal approach depending on surgeon expertise, as well as tumor and patient characteristics.

Conclusions and Relevance

Twenty-six clinically relevant and evidence-based recommendations are provided to assist surgeons with perioperative adrenal care.

Proposed Risk Stratification and Patterns of Radioactive Iodine Therapy in Malignant Struma Ovarii

Introduction: Malignant struma ovarii (MSO) is a rare thyroid cancer arising within an ovarian teratoma. While surgical excision of the primary tumor is widely accepted as standard of care, recommendations for adjuvant treatment of MSO-whether or not to administer radioactive iodine (RAI)-are based largely on case reports and remain debated. In this study, we aimed to propose a risk stratification and analyze RAI utilization patterns in MSO cases. Methods: The National Cancer Database (NCDB) was queried for patients with MSO between 2004 and 2016. Demographic, oncological, and clinicopathologic data were compared between groups using Fisher's exact test. Kaplan-Meier curves were used to estimate overall survival (OS), and variables associated with OS were assessed via univariate Cox regression. We adapted the 2015 American Thyroid Association risk guidelines for MSO patients. We stratified patients into low-, intermediate-, and high-risk groups using metastasis, extraovarian extension, lymphovascular invasion, lymph node status, surgical margins, tumor size, and grade. Risk stratification, demographic, oncological, and clinicopathologic data were compared between the groups receiving and not receiving RAI therapy. We then queried the Surveillance, Epidemiology, and End Results (SEER) 18 registry for patients with MSO between 2000 and 2018 to confirm our risk stratification analysis. Results: In the NCDB analysis, a total of 158 patients were identified, and 19 received RAI. RAI therapy was associated with distant metastasis (p = 0.005) and lymph node status (p = 0.012). Twenty-one NCDB patients were stratified as high risk, and 30% of high-risk patients received RAI. High-risk stratification was associated with decreased OS via univariate Cox regression (hazard ratio = 4.0 [95% confidence interval 1.11-14.26], p = 0.034). In our subsequent analysis using the SEER registry, there were 95 MSO patients, and 18 received RAI. Again, the majority of high-risk patients did not receive RAI, with only 41% of high-risk patients receiving RAI. Conclusions: MSO is a rare malignancy with apparently variable and inconsistent patterns of postoperative RAI administration. The risk stratification described here provides a framework to identify patients potentially at risk for mortality, and utilization of RAI in this group should be studied further.

Quantifying physiologic parameters of the gastroesophageal junction during re-operative anti-reflux surgery

BACKGROUND

Hiatal hernia re-approximation during index anti-reflux surgery (ARS) contributes approximately 80% of overall change in distensibility index (DI) and, potentially, compliance of the gastroesophageal (GEJ), while sphincter augmentation contributes approximately 20%. Whether this is seen in re-operative ARS is unclear. We quantify the physiologic parameters of the GEJ at each step of robotic re-operative ARS and compare these to index ARS.

METHODS

Robotic ARS with hiatal hernia repair was performed on 195 consecutive patients with pathologic reflux utilizing EndoFLIP™, of which 26 previously had ARS. Intra-operative GEJ measurements, including cross-sectional area (CSA), pressure, DI, and high-pressure zone (HPZ) length were collected pre-repair, post-diaphragmatic re-approximation, post-mesh placement, and post-lower-esophageal sphincter (LES) augmentation.

RESULTS

Both cohorts were similar by sex and BMI and underwent similar procedures. The re-operative cohort was older (60.6 ± 15.3 vs. 52.7 ± 16.2 years, p = 0.03), had more frequent pre-operative dysphagia (69.2% vs. 42.6%, p = 0.01) and esophageal dysmotility on barium swallow (75.0% vs. 35.0%, p < 0.001) but lower rates of hiatal hernia on endoscopy (30.8% vs. 68.7%, p < 0.001) compared to index procedures. Among the re-operative cohort, the CSA decreased by 34 (IQR - 80, - 15) mm2 and DI 1.1 (IQR - 2.4, - 0.6) mm2/mmHg (both p < 0.001). Pressure increased by 11.2 (IQR 4.7, 14.9) mmHg and HPZ by 1.5 (1,2) cm (both p < 0.001). These changes were similar to those seen in index ARS. Diaphragmatic re-approximation contributed to a greater percentage of overall change to the GEJ than did the augmentation procedure, with 72% of the change in DI occurring during hiatal closure, similar to that seen during index ARS.

CONCLUSIONS

During re-operative ARS, dynamic intra-operative monitoring can quantify the effects of each operative step on GEJ physiologic parameters. Diaphragmatic re-approximation appears to have a greater effect on GEJ physiology than does LES-sphincter augmentation during both index and re-operative ARS.

Risk factors for venous thromboembolism (VTE) after adrenalectomy for adrenal cortical neoplasms

BACKGROUND

Incidence of venous thromboembolism (VTE) after adrenalectomy for adrenal cortical carcinoma (ACC) is unknown. Herein, we aim to identify the relative incidence and risk factors of VTE after adrenalectomy for ACC.

METHODS

The American College of Surgeons National Surgical Quality Improvement Program database was queried to identify patients who underwent adrenalectomy for ACC, Cushing syndrome (CS), and benign adrenal cortical syndromes (BACS). Univariable and multivariable analyses were used to determine clinical characteristics, 30-day postoperative VTE occurrences, and associated risk factors. Khorana oncologic risk score (KRS) for VTE was calculated and compared between groups.

RESULTS

A total of 5896 patients were analyzed: 576 ACC, 371 CS, and 4949 BACS. Postoperative VTE occurred 0.9%, with the highest rate occurring in ACC (2.6% ACC vs. 1.6% CS vs. 0.7% BACS, p < 0.001). Forty percent of VTEs in the ACC cohort were diagnosed postdischarge. ACC patients with KRS ≥ 2 had a 9.6% incidence of VTE (p = 0.007). Multivariable analysis identified increased age (p = 0.03), presence of adrenal cancer (p = 0.01), and KRS ≥ 2 (p = 0.005) as risk factors for VTE after adrenalectomy.

CONCLUSIONS

Postoperative VTE after adrenalectomy occurs most frequently for ACC. ACC patients with increased age and/or Khorana score ≥2 should be considered for extended VTE prophylaxis.

BRAF inhibition promotes ER stress-mediated cell death in uveal melanoma

Melanoma with a BRAF mutation is more common to develop into a fatal disease. BRAF mutation inhibitor-induced autophagy affects the drug efficacy in many cancer types. The role of autophagy during BRAF inhibition in uveal melanoma (UM) remains unclear. In this study, we examined the autophagic flux and compared the number of autophagic vacuoles during the BRAF inhibition in UM. The PKR-like endoplasmic reticulum (ER) kinase (PERK) arm was studied to test whether the ER stress was involved. The effects of downregulation of ER stress by targeting the PERK arm (pharmacologically and genetically) were also assessed. We found a dose-dependent increase of autophagic flux in OCM1A cells during the BRAF inhibition. This phenomenon was further verified by an enhanced number of GFP-LC3 puncta and was finally confirmed by raised autophagic index examined by transmission electron microscopy. Pathway analysis revealed that the vemurafenib (the BRAF inhibitor)-induced autophagy was independent of the MAPK signaling pathway. Instead, it was possibly regulated via the enhanced ER stress response. We further found that the inhibition of ER stress response rescued cell death. Therefore, our results suggest BRAF inhibition promotes ER stress response-induced autophagy in UM. Targeting ER stress response can partially revert autophagy and rescue cell death, which may impair the anti-tumor effect of BRAF inhibitor in UM.

Exposure to Polybrominated Diphenyl Ether Flame Retardants Causes Deoxyribonucleic Acid Damage in Human Thyroid Cells In Vitro

INTRODUCTION

The incidence of papillary thyroid cancer (PTC) in the United States has tripled in the past 30 y. Polybrominated diphenyl ethers (PBDEs) are flame retardants that were ubiquitously used over that time period, and exposure to PBDEs has been associated with PTC prevalence. They are potential carcinogens via their induction of reactive oxygen species (ROS) formation and resultant deoxyribonucleic acid (DNA) damage. We sought to determine the effects of PBDE and tris(2-chloroethyl) phosphate (TCEP), another flame retardant implicated in PTC incidence, on thyrocytes in vitro and measure PBDE levels in human thyroid tissue to determine their carcinogenic potential.

METHODS

Nthy-Ori, an immortalized benign human thyroid follicular cell line was used as a model of normal human thyroid. MTT assays were used to measure cell viability after exposure to PBDEs and TCEP. ROS levels and double-stranded and single-stranded DNA breaks were measured to determine genotoxicity. DNA damage response protein levels were measured with immunoblotting.

RESULTS

Exposure to 20μM PBDE or TCEP for 48 h had minimal effects on thyrocyte viability. There was no significant increase in intracellular ROS up to 6 h following PBDE or TCEP exposure in thyrocytes; however, cells exposed to PBDE 47 showed evidence of DNA single-stranded and double-stranded breaks. There was a dose-dependent increase in γH2AX levels following exposure to PBDEs 47 and 209 in Nthy-Ori cells but not with TCEP treatment.

CONCLUSIONS

PBDE 47 and 209 demonstrated genotoxicity but not cytotoxicity in follicular thyrocytes in vitro. Therefore, PBDE 47 and 209 may be carcinogenic in human thyroid cells.

Abstract 5579: First-in-human study of ICAM-1-specific affinity tuned CAR T cells against advanced thyroid cancer

Background: The use of chimeric antigen receptor (CAR) T cells for solid tumors has a number of challenges, such as lack of tumor-specific targets, CAR T cell exhaustion, and the immunosuppressive tumor microenvironment. To address these challenges, AffyImmune has developed technologies to affinity tune and track CAR T cells in patients. The targeting moiety is affinity tuned to preferentially bind to tumor cells overexpressing the target while leaving normal cells with low basal levels untouched, thereby increasing the therapeutic window and allowing for more physiological T cell killing. The CAR T cells are engineered to co-express somatostatin receptor 2 (SSTR2), which allows for the tracking of CAR T cells in vivo via PET/CT scan using FDA-approved DOTATATE.

Methods: AIC100 was generated by affinity tuning the I-domain of LFA-1, the physiological ligand to ICAM-1. Various mutants with 106-fold difference in affinity were evaluated for structure activity relationships using targets with varying antigen densities. The AIC100 with micromolar affinity was clearly the most effective in non-clinical animal models. AIC100 is currently being evaluated to assess safety, CAR T expansion, tumor localization, and preliminary activity in patients with advanced thyroid cancer (ATC) in a phase I study (NCT04420754). Our study uses a modified toxicity probability interval design with three dosage groups of 10 × 106, 100 × 106, and 500 × 106 cells.

Results: Preclinical studies demonstrated greater in vivo anti-tumor activity and safety with micromolar affinity CAR T cells. A single dose of AIC100 resulted in tumor elimination and significantly improved survival of animals bearing ATC xenografts. AIC100 activity was confirmed in other high ICAM-1 tumor models including breast cancer, gastric cancer, and multiple myeloma. In a Phase I patient given 10 × 106 CAR T cells, near synchronous imaging of FDG and DOTATATE revealed preliminary evidence of transient CAR T expansion and tumor reduction at multiple tumor lesions, with the peak of CAR T cell density coinciding with the spike in CAR T cell numbers in blood.

Conclusion: We have developed affinity tuned CAR T cells designed to selectively target ICAM-1 overexpressing tumor cells and to spatiotemporally image CAR T cells. Near-synchronous FDG and DOTATATE scans will enhance patient safety by early detection of off-tumor CAR T activity and validation of tumor response. We anticipate that our “tune and track” technology will be widely applicable to developing potent yet safe CAR T cells against hard-to-treat solid cancers.

Citation Format: Jingmei Hsu, Yen-Michael Hsu, Koen van Besien, Thomas J. Fahey, Jana Ivanidze, Janusz Puc, Karrie Du, Yanping Yang, Yogindra Vedvyas, Irene M. Min, Eric von Hofe, Moonsoo M. Jin. First-in-human study of ICAM-1-specific affinity tuned CAR T cells against advanced thyroid cancer [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr 5579.

Abstract 5270: Developing a predictive model for pancreatic neuroendocrine tumor metastatic potential: A multi-institutional analysis

Pancreatic neuroendocrine tumors (PNETs) are rare neoplasms that arise from cells in the islets of Langerhans, with surgical resection presently recommended for tumors &gt; 2cm. While many PNETs have the propensity to be indolent, some small tumors display aggressive features with early metastatic potential. We used machine learning to develop a predictive model of metastatic potential dependent upon the transcriptomic signature of primary PNET tissue. To build this model, RNA sequencing data was obtained from the primary tissue of 96 surgically-resected PNETs from various institutions. Two cohorts were generated with equally balanced metastatic PNET composition (15 (32.6%) vs. 13 (26.5%), p=0.52). A differential gene expression analysis identified 20 concordantly differentially expressed genes associated with metastatic status between the two cohorts. Unsupervised surrogate variable analysis estimated and adjusted for significant sources of variation not related to metastatic potential and mitigated unwanted noise and batch effects. A gene set enrichment analysis identified an additional 29 genes that most frequently contributed to the enriched biologic pathways extrapolated from the sequencing data. Log transformed, batch corrected TPM values for these 49 genes were combined with an additional 10 clinically-relevant genes, including ARX and PDX1, that are known to contribute to PNET signatures or oncogenesis. The datasets were subsequently randomized in a 1:1 ratio and informative features with respect to metastatic status were identified utilizing a Boruta algorithm, with a priori exclusion of highly-correlative genes and those that displayed near zero variance. Nine genes, including AURKA, ARX, CDCA8, CPB2, MYT1L, NDC80, PAPPA2, SFMBT1 and ZPLD1, were identified as sufficient to classify the localized or metastatic outcome. Distributed random forests (DRF), generalized linear models (GLM), gradient boosting machines (GBM) and extreme gradient boosting (XGBoost) models were trained utilizing these 9 genes. Training ROC ranged from 0.92 for DRF to 1 for XGboost. When applied to 47 independent validation samples, the testing sensitivity ranged from 75% for DRF to 94% for GBM; specificity ranged from 84% for DRF to 94% to XGboost and GLM; positive predictive value ranged from 72% for DRF to 86% for GLM; negative predictive value ranged from 88% for GLM to 97% to GBM. The degree of predictive agreement between models ranged from 64% to 91%. Taken together, we have developed a highly sensitive predictive model of the metastatic PNET phenotype that is based on expression of nine genes. Its application as a guide for management should be studied prospectively in patients with newly diagnosed PNETs.

Citation Format: Jacques A. Greenberg, Nikolay A. Ivanov, Yajas Shah, Scott Kulm, Jelani Williams, Catherine G. Tran, Theresa Scognamiglio, Yeon Joo Lee, Caitlin E. Egan, Irene M. Min, Rasa Zarnegar, James Howe, Xavier Keutgen, Thomas J. Fahey, Olivier Elemento, Brendan M. Finnerty. Developing a predictive model for pancreatic neuroendocrine tumor metastatic potential: A multi-institutional analysis [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr 5270.

Phase I study of AIC100 in relapsed and/or refractory advanced thyroid cancer and anaplastic thyroid cancer

6093

Background: ICAM-1 is a cell surface glycoprotein that is typically expressed on endothelial cells and immune cells and a ligand for LFA-1 integrin. It is also overexpressed in several malignancies, in particular anaplastic and advanced thyroid cancer. We designed an affinity tuned ICAM-1-directed CAR T cell (micromolar affinity) that preferentially binds overexpressed ICAM-1 on tumor cells and spares normal cells. The CAR T cells also express somatostatin receptor 2 (SSTR2), which allows tracking of CAR T cells in vivo via DOTATATE PET/CT scan. Murine studies showed excellent responses in ICAM-1 expressing thyroid cancer without significant toxicities. We are conducting a first-in-human phase 1 clinical trial to evaluate the feasibility, safety and preliminary efficacy of ICAM-1 in patients with relapsed/refractory thyroid cancer or anaplastic thyroid cancer who are BRAF wild-type, or BRAF mutated after failure of BRAF specific therapy (NCT04420754). Methods: This is a dose-escalation study with modified toxicity probability interval design and cohorts of 3 Patients. Patients receive a single dose of 1x 107 (Cohort 1), 1 x 108 (Cohort 2) or 5 x 108 (Cohort 3) ICAM-1 CAR T cells after FLU/CY lymphodepleting (LD) chemotherapy. Additional CAR T infusion is allowed if patients achieve partial response or stable disease. Whole-body Fluorodeoxyglucose (FDG) and DOTATATE PET/CT is used to stage tumor and track CAR T cells in vivo, respectively. Results: All ICAM-1 CAR T infusion products met target transduction efficiency. Two patients with progressive anaplastic thyroid cancer received ICAM-1 CAR T therapy at dose-level I. Evaluation of CAR T cellular kinetics demonstrated transient peripheral blood CAR T cell expansion. One patient developed grade 1 cytokine release syndrome (CRS) with fever. Several tumor lesions from this patient showed DOTATATE avidity, indicating CAR T homing to the tumor, concomitant with decrease in FDG avidity, suggesting biological activity at ̃2 weeks post CAR T infusion. DOTATATE avidity at 2 weeks post CAR T infusion also appeared to match that of CAR T abundance in the blood. Updated results on additional patients and cohorts will be presented. Conclusions: Adoptive cellular therapy with ICAM-1 directed CAR T is safe and feasible at dose level 1 in patients with anaplastic thyroid cancer. DOTATATE PET allows visualization of expansion and homing of SSTR2 expressing CAR T cells, while concomitant FDG PET permits correlation with biological activity. Clinical trial information: NCT04420754.

Preoperative Thyroid Peroxidase Antibody Predicts Recurrence in Papillary Thyroid Carcinoma: A Consecutive Study With 5,770 Cases

Background

Thyroid autoimmunity is common in papillary thyroid carcinoma (PTC) and was believed to confer a better prognosis; however, controversy still remains. This study aimed to investigate the prognostic value of chronic lymphocytic thyroiditis (CLT) and preoperative thyroid peroxidase antibody (TPOAb) in PTC patients.

Methods

A retrospective analysis was performed on 5,770 PTC patients who underwent surgical treatment with pathologically confirmed PTC in our institution between 2012 to 2016. The patients were divided into groups with respect to the coexistence of CLT or preoperative TPOAb levels. The clinicopathological characteristics and disease-free survival (DFS) rates were compared between the groups.

Results

The coexistence of CLT was likely to have bilateral, multifocal tumors. Particularly, PTC patients with TPOAb++ (&gt;1,000 IU/L) had a larger tumor size (p = 0.007) and higher rates of bilaterality and multifocality than those with TPOAb− (TPOAb&lt; 100 IU/L), while for lymph node metastasis and extrathyroidal extension, there is no statistical difference. Tumor recurrence was found in 15 of 425 (3.5%), 9 of 436 (2.1%), and 56 of 3,519 (1.6%) patients with TPOAb++, TPOAb+, and TPOAb−, respectively (p = 0.017). On univariate analysis, TPOAb++ was correlated with tumor recurrence, with a hazard ratio of 2.20 [95% confidence interval (CI), 1.25–3.89], which remained as an independent risk factor at 1.98 (95% CI, 1.10–3.55) on multivariate analysis. PTC patients with TPOAb++ had the lowest DFS rates (96.5 vs. 97.9 vs. 98.4%, p = 0.020).

Conclusion

CLT is not a protective factor in PTC patients. We provide initial evidence that the preoperative TPOAb instead predicts recurrence in papillary thyroid carcinoma.

A machine-learning algorithm for distinguishing malignant from benign indeterminate thyroid nodules using ultrasound radiomic features

Background: Ultrasound (US)-guided fine needle aspiration (FNA) cytology is the gold standard for the evaluation of thyroid nodules. However, up to 30% of FNA results are indeterminate, requiring further testing. In this study, we present a machine-learning analysis of indeterminate thyroid nodules on ultrasound with the aim to improve cancer diagnosis. Methods: Ultrasound images were collected from two institutions and labeled according to their FNA (F) and surgical pathology (S) diagnoses [malignant (M), benign (B), and indeterminate (I)]. Subgroup breakdown (FS) included: 90 BB, 83 IB, 70 MM, and 59 IM thyroid nodules. Margins of thyroid nodules were manually annotated, and computerized radiomic texture analysis was conducted within tumor contours. Initial investigation was conducted using five-fold cross-validation paradigm with a two-class Bayesian artificial neural networks classifier, including stepwise feature selection. Testing was conducted on an independent set and compared with a commercial molecular testing platform. Performance was evaluated using receiver operating characteristic analysis in the task of distinguishing between malignant and benign nodules. Results: About 1052 ultrasound images from 302 thyroid nodules were used for radiomic feature extraction and analysis. On the training/validation set comprising 263 nodules, five-fold cross-validation yielded area under curves (AUCs) of 0.75 [Standard Error (SE) = 0.04; P < 0.001 ] and 0.67 (SE = 0.05; P = 0.0012 ) for the classification tasks of MM versus BB, and IM versus IB, respectively. On an independent test set of 19 IM/IB cases, the algorithm for distinguishing indeterminate nodules yielded an AUC value of 0.88 (SE = 0.09; P < 0.001 ), which was higher than the AUC of a commercially available molecular testing platform (AUC = 0.81, SE = 0.11; P < 0.005 ). Conclusion: Machine learning of computer-extracted texture features on gray-scale ultrasound images showed promising results classifying indeterminate thyroid nodules according to their surgical pathology.

RET Fusion-Positive Papillary Thyroid Cancers are Associated with a More Aggressive Phenotype

BACKGROUND

It is unclear if different genetic drivers in papillary thyroid cancer (PTC) confer different phenotypic tumor behavior leading to more aggressive disease. We hypothesized that RET-driven cancers are more aggressive.

PATIENTS AND METHODS

We reviewed records of consecutive patients treated for newly diagnosed PTC at this single institution from 2015 to 2016. Tumor samples from these patients were genotyped to identify RET-translocated, BRAFV600E mutant, and HRAS, KRAS, and NRAS mutant tumors. Patient demographic, clinicopathologic, and outcomes data were compared to identify genotype-specific patterns of disease.

RESULTS

Of the 327 patients who underwent initial surgery for PTC during the study period, 192 (58.7%) had BRAFV600E mutant tumors (BRAF), 14 (4.3%) had RET-rearranged tumors (RET), 46 (14.1%) had RAS mutant tumors (RAS), and 75 (22.9%) had BRAF, RET, and RAS wildtype tumors. RET-driven tumors were more likely to have extrathyroidal extension (50.0% versus 27.0% for BRAF and 2.2% for RAS, P < 0.001), multifocal disease (85.7% versus 60.3%, and 44.4%, respectively, P = 0.017), and distant metastases (14.3% versus 1.1%, and 0%, respectively, P = 0.019). RET and BRAF patients also had worse disease-free survival than RAS patients (Kaplan-Meier log rank, P = 0.027).

CONCLUSIONS

Patients with RET-driven PTCs had higher rates of extrathyroidal extension, multifocal disease, and distant metastases than patients whose tumors had BRAFV600E or RAS mutations. Patients with RET-rearranged tumors had similar disease-free survival to patients with BRAFV600E mutant tumors. RET rearrangement may confer an aggressive phenotype in PTC.

Evaluation of post-operative dysphagia following anti-reflux surgery

BACKGROUND

Anti-reflux surgery (ARS) has known long-term complications, including dysphagia, bloat, and flatulence, among others. The factors affecting the development of post-operative dysphagia are poorly understood. We investigated the correlation of intra-operative esophagogastric junction (EGJ) characteristics and procedure type with post-operative dysphagia following ARS.

METHODS

Robotic ARS was performed on 197 consecutive patients with pathologic reflux utilizing EndoFLIP™ technology. Intraoperative EGJ measurements including distensibility index (DI), cross-sectional area (CSA), and high-pressure zone (HPZ) length were collected. Dysphagia was assessed pre-operatively and at 3 months post-operatively.

RESULTS

The median pre-operative DI for all procedures was 2.6 (IQR 1.6-4.5) mm²/mmHg. There was no difference in post-operative DI between procedures [Hill: 0.9 (IQR 0.7-1.1) mm²/mmHg, Nissen: 1.0 (IQR 0.7-1.4) mm²/mmHg, Toupet: 1.2 (IQR 0.8-1.5) mm²/mmHg, Linx: 1.0 (IQR 0.7-1.2) mm²/mmHg, p = 0.24], whereas post-operative HPZ length differed by augmentation type [Hill: 3 (IQR 2.8-3) cm, Nissen: 3.5 (IQR 3-3.5) cm, Toupet: 3 (IQR 2.5-3.5) cm, Linx: 2.5 (IQR 2.5-3) cm, p = 0.032]. Eighty-nine patients (45.2%) had pre-operative dysphagia. Thirty-two patients (27.6%) reported any dysphagia at their 3-month post-operative visit and 12 (10.3%) developed new or worsening post-operative dysphagia [Hill: 2/18 (11.1%), Nissen: 2/35 (5.7%), Toupet: 4/54 (7.4%), Linx: 4/9 (44.4%), p = 0.006]. The median pre-operative and post-operative DI of patients who developed new or worsening dysphagia was 2.0 (IQR 0.9-3.8) mm²/mmHg and 1.2 (IQR 1.0-1.8) mm²/mmHg, respectively, and that of those who did not was 2.5 (IQR 1.6-4.0) mm²/mmHg and 1.0 (IQR 0.7-1.4) mm²/mmHg (p = 0.21 and 0.16, respectively).

CONCLUSIONS

Post-operative DI was similar between procedures, and there was no correlation with new or worsening post-operative dysphagia. Linx placement was associated with higher rates of new or worsening post-operative dysphagia despite a shorter post-procedure HPZ length and similar post-operative DI when compared to other methods of LES augmentation.

Association of the Affordable Care Act with access to highest-volume centers for patients with thyroid cancer

BACKGROUND

Disparities exist in access to high-volume surgeons, who have better outcomes after thyroidectomy. The association of the Affordable Care Act's Medicaid expansion with access to high-volume thyroid cancer surgery centers remains unclear.

METHODS

The National Cancer Database was queried for all adult thyroid cancer patients diagnosed from 2010 to 2016. Hospital quartiles (Q1-4) defined by operative volume were generated. Clinicodemographics and adjusted odds ratios for treatment per quartile were analyzed by insurance status. An adjusted difference-in-differences analysis examined the association between implementation of the Affordable Care Act and changes in payer mix by hospital quartile.

RESULTS

In total, 241,448 patients were included. Medicaid patients were most commonly treated at Q3-Q4 hospitals (Q3 odds ratios 1.05, P = .020, Q4 1.11, P < .001), whereas uninsured patients were most often treated at Q2-Q4 hospitals (Q2 odds ratios 2.82, Q3 2.34, Q4 2.07, P < .001). After expansion, Medicaid patients had lower odds of surgery at Q3-Q4 compared with Q1 hospitals (odds ratios Q3 0.82, P < .001 Q4 0.85, P = .002) in expansion states, but higher odds of treatment at Q3-Q4 hospitals in nonexpansion states (odds ratios Q3 2.23, Q4 1.86, P < .001). Affordable Care Act implementation was associated with increased proportions of Medicaid patients within each quartile in expansion compared with nonexpansion states (Q1 adjusted difference-in-differences 5.36%, Q2 5.29%, Q3 3.68%, Q4 3.26%, P < .001), and a decrease in uninsured patients treated at Q4 hospitals (adjusted difference-in-differences -1.06%, P = .001).

CONCLUSIONS

Medicaid expansion was associated with an increased proportion of Medicaid patients undergoing thyroidectomy for thyroid cancer in all quartiles, with increased Medicaid access to high-volume centers in expansion compared with nonexpansion states.

Can general surgery interns accurately measure their own technical skills? Analysis of cognitive bias in surgical residents' self-assessments

BACKGROUND

Accurate self-assessment of knowledge and technical skills is key to self-directed education required in surgical training. We aimed to investigate the presence and magnitude of cognitive bias in self-assessment among a cohort of surgical interns.

METHODS

First-year general surgery residents self-assessed performance on a battery of technical skill tasks (knot tying, suturing, vascular anastomosis, Fundamentals of Laparoscopic Skills peg transfer and intracorporeal suturing) at the beginning of residency. Each self-assessment was compared to actual performance. Bias and deviation were defined as arithmetic and absolute difference between actual and estimated scores. Spearman correlation assessed covariation between actual and estimated scores. Improvement in participant performance was analyzed after an end-of-year assessment.

RESULTS

Participants (N = 34) completed assessments from 2017 to 2019. Actual and self-assessment scores were positively correlated (0.55, P < .001). Residents generally underestimated performance (bias -4.7 + 8.1). Participants who performed above cohort average tended to assess themselves more negatively (bias -7.3 vs -2.3) and had a larger discrepancy between self and actual scores than below average performers (deviation index 9.7 + 8.2 vs 3.8 + 3.1, P < .05). End-of-year total scores improved in 31 (91.2%) participants by an average of 11 points (90 possible). Least accurate residents in initial self-assessments (deviation indices >75th percentile) improved less than more accurate residents (median 5 vs 16 points, P < .05). All residents with a deviation index >75 percentile underestimated their performance.

CONCLUSION

Cognitive bias in technical surgical skills is apparent in first-year surgical residents, particularly in those who are higher performers. Inaccuracy in self-assessment may influence improvement and should be addressed in surgical training.

Ablation therapy using a low dose of radioiodine may be sufficient in low- to intermediate-risk patients with follicular variant papillary thyroid carcinoma

OBJECTIVES

Follicular variant papillary thyroid carcinoma (FVPTC) is treated similarly to classical variant papillary thyroid carcinoma (cPTC). However, FVPTC has unique tumour features and behaviours. We investigated whether a low dose of radioiodine was as effective as a high dose for remnant ablation in patients with FVPTC and evaluated the recurrence of low-intermediate risk FVPTC.

METHODS

Data from cPTC and FVPTC patients treated with I-131 from 2004 to 2014 were reviewed. Demographics, tumour behaviour, lymph node metastasis, and local recurrence data were compared between FVPTC and cPTC patients. Then, low-intermediate risk FVPTC patients were divided into low, intermediate, and high I-131 dose groups, and postoperative I-131 activities were analysed to evaluate the effectiveness of I-131 therapy for thyroid remnant ablation.

RESULTS

In total, 799 cases of FVPTC (n = 168) and cPTC (n = 631) treated with I-131 were identified. Patients with FVPTC had a larger primary nodule size than cPTC, but lymph node metastases and local recurrence were more prevalent in cPTC than in FVPTC. For the low-, intermediate-, and high-dose groups, success rates of ablation did not differ (82.0%, 80%, and 81.3%, respectively).

CONCLUSION

FVPTC differs from cPTC in behaviour. Low-dose ablation may be sufficient in FVPTC patients with low-intermediate disease risk.

Association of Adrenal Venous Sampling With Outcomes in Primary Aldosteronism for Unilateral Adenomas

Importance

Adrenal venous sampling is recommended prior to adrenalectomy for all patients with hyperaldosteronism; however, cross-sectional imaging resolution continues to improve, while the procedure remains invasive and technically difficult. Therefore, certain patients may benefit from advancing straight to surgery.

Objective

To determine whether clinical and biochemical resolution varied for patients with primary aldosteronism with unilateral adenomas who underwent adrenal venous sampling vs those who proceeded to surgery based on imaging alone.

Design, Setting, and Participants

Retrospective, international cohort study of patients treated at 3 tertiary medical centers from 2004 to 2019, with a median follow-up of approximately 6 months. A total of 217 patients were consecutively enrolled. Exclusion criteria consisted of unknown postoperative serum aldosterone level and imaging inconsistent with unilateral adenoma with a normal contralateral gland. A total of 125 patients were included in the analysis. Data were analyzed between October 2019 and July 2020.

Exposures

Adrenal venous sampling performed preoperatively.

Main Outcomes and Measures

The primary outcome measurements were the clinical and biochemical success rates of surgery for the cure of hyperaldosteronism secondary to aldosterone-producing adenoma.

Results

A total of 125 patients were included (45 cross-sectional imaging with adrenal venous sampling and 80 imaging only). The mean (SD) age of the study participants was 50.2 (10.6) years and the cohort was 42.4% female (n = 53). Of those patients for whom race or ethnicity were reported (n = 80), most were White (72.5%). Adrenal venous sampling failure rate was 16.7%, and the imaging concordance rate was 100%. Relevant preoperative variables were similar between groups, except ambulatory systolic blood pressure, which was higher in the imaging-only group (150 mm Hg; interquartile range [IQR], 140-172 mm Hg vs 143 mm Hg, IQR, 130-158 mm Hg; P = .03). Resolution of autonomous aldosterone secretion was attained in 98.8% of imaging-only patients and 95.6% of adrenal venous sampling patients (P = .26). There was no difference in complete clinical success (43.6% [n = 34] vs 42.2% [n = 19]) or partial clinical success (47.4% [n = 37] vs 51.1% [n = 23]; P = .87) between groups. Complete biochemical resolution was similar as well (75.9% [n = 41] vs 84.4% [n = 27]; P = .35). There was no difference in clinical or biochemical cure rates when stratified by age, although complete clinical success rates downtrended in the older cohorts, and sample sizes were small.

Conclusions and Relevance

Given the improved sensitivity of cross-sectional imaging in detection of adrenal tumors, adrenal venous sampling may be selectively performed in appropriate patients with clearly visualized unilateral adenomas without affecting outcomes. This may facilitate increased access to surgical cure for aldosterone-producing adenomas and will decrease the incidence of morbidities associated with the procedure.

A Comparison of the Seventh and Eighth Editions of the AJCC Staging Systems to Predict Recurrence in Papillary Thyroid Microcarcinoma

BACKGROUND

The incidence of papillary thyroid microcarcinoma has been constantly rising in recent decades. The tumor, node, metastasis staging system is designed to predict prognosis in patients with papillary thyroid carcinoma. Recent studies have shown that the American Joint Committee on Cancer (AJCC) 8th edition is superior to the 7th edition for predicting tumor recurrence in PTC patients. To date, whether the 8th edition is also better able to predict recurrence in papillary thyroid microcarcinoma (PTMC) remains unclear.

METHOD

We enrolled 1007 cases from our thyroid cancer database in the First Affiliated Hospital, Zhejiang University School of Medicine, from 1997 to 2011. Univariable and multivariate Cox hazard regression analyses were used to identify the association between variables and recurrence. Disease-free survival was calculated using the Kaplan-Meier method and compared using the log-rank test.

RESULTS

A total of 1007 PTMC patients were enrolled, with a median follow-up of 67 months. Of 93 (9.2%) patients downstaged by the changes in versions, 49 (52.7%) were downstaged because the age-at-diagnosis cut-off used for staging increased from 45 to 55 years, while 35 (37.6%) were downstaged due to the weakening of the effects of lymph node metastasis. The recurrence rate of PTMC was 4.17%. Univariate Cox hazards regression analyses showed that TNM stage according to the AJCC 8th edition was significantly associated with recurrence, while the recurrence survival curves showed that TNM stage (stage I vs. stage II-IV) according to the AJCC 8th edition, but not the 7th edition, was significantly associated with disease-free survival (p < 0.05).

CONCLUSIONS

The AJCC 8th edition has better ability to predict recurrence in PTMC patients than the 7th edition.

Frailty is More Predictive than Age for Complications After Thyroidectomy for Multinodular Goiter

BACKGROUND

Risks of thyroidectomy for multinodular goiter (MNG) in older and frail patients are unclear, particularly regarding hematoma and recurrent laryngeal nerve (RLN) palsy.

METHODS

MNG patients undergoing total thyroidectomy were reviewed in the ACS-NSQIP procedure-targeted database (2016-2017). Outcomes were analyzed between adult (age <65), older-adult (age ≥65 and <80), and oldest-old (age ≥80) patients. Five-factor modified frailty index (mFI-5) was calculated based on functional status, diabetes, COPD, CHF, and hypertension, and used in comparative analyses.

RESULTS

A total of 2189 adult, 635 older-adult, and 59 oldest-old patients were included. Compared to adult patients, older-adult and oldest-old patients had higher mFI-5 ≥0.4 rates (14% vs. 22% vs. 31%, respectively, p < 0.001). The overall complication rate was 17.0% and similar between groups; however, oldest-old patients had higher rates of surgical site infection (3.4% vs. 0.3% vs. 0.4%), pneumonia (5.1% vs. 0.3% vs. 0.2%), and readmission (10.2% vs. 2.4% vs. 2.6%) compared to older-adult and adult patients, respectively (p < 0.05). On multivariable analyses of thyroidectomy-specific complications, mFI-5 ≥0.4 (OR 2.5, 95%-CI 1.4-4.4) and bleeding disorder (OR 4.6, 95%-CI 1.3-16.3) were predictive of hematoma, whereas vessel-sealant device usage (OR 0.4, 95%-CI 0.3-0.7) was protective. mFI-5 ≥ 0.4 (OR 1.5, 95%-CI 1.1-2.2), bleeding disorder (OR 2.8, 95%-CI 1.04-7.8), parathyroid autotransplantation (OR 1.7, 95%-CI 1.2-2.6), and prolonged operative time (OR 1.4, 95%-CI 1.02-1.8) were predictive of RLN palsy. Age was not a significant predictor of hematoma or RLN palsy.

CONCLUSIONS

Patients ≥80 years old are at increased risk for systemic complications and readmission after thyroidectomy for MNG. Frailty index better risk-stratifies patients than age for thyroidectomy-specific complications.

The impact of pneumoperitoneum on esophagogastric junction distensibility during anti-reflux surgery

OBJECTIVE

We aimed to quantify the contribution of pneumoperitoneum on compliance of the esophagogastric junction (EGJ) during anti-reflux surgery.

BACKGROUND

Compliance of the EGJ is reduced with anti-reflux surgery. EndoFLIP® planimetry can be used to assess dynamic changes of EGJ compliance intraoperatively. It is unclear how pneumoperitoneum impacts intraoperative measurements by EndoFLIP® and the implications thereof on validity of the results. Therefore, determining variability in EndoFLIP® measurements based on pneumoperitoneum is warranted to establish guidelines to interpret clinical outcomes.

METHODS

Primary anti-reflux surgery was performed on 39 consecutive patients with pathologic reflux. Intraoperative EGJ measurements including distensibility index (DI), cross-sectional area (CSA), and intrabag pressure were collected using EndoFLIP® at 0, 10, and 15 mmHg of intraperitoneal pressure. Data were acquired pre-procedure, post-hiatal hernia repair, and post-LES augmentation with fundoplications.

RESULTS

Patients underwent Nissen (13.2%), Toupet (68.4%), LINX (10.5%), or Hill-fundoplications (7.9%). There was no difference between 0 and 10 mmHg of pneumoperitoneum in CSA, pressure, or DI measurements pre-procedure; however, there was a difference between 0 and 15 mmHg in pressure (p = 0.016) and DI (p = 0.023) measurements. After LES augmentation, 10 mmHg intraperitoneal pressure reduced DI, though the absolute difference is small (2.0 vs. 1.5 mm²/mmHg, p = 0.002).

CONCLUSION

Pneumoperitoneum affected EGJ distensibility at 15 mmHg, but not 10 mmHg, of insufflation prior to anti-reflux procedures. After anti-reflux surgery, there was a significant variance between 0 and 10 mmHg of pneumoperitoneum in pressure and distensibility. The change in pressure appears linear and needs to be considered if procedural modifications are performed based on intraoperative findings and when evaluating clinical outcomes.

Preoperative molecular testing in thyroid nodules with Bethesda VI cytology: Clinical experience and review of the literature

Risk assessment is critical to determine the timing of elective surgeries and preserve valuable resources in time of pandemic. This study was undertaken to better understand the potential value of molecular testing to risk‐stratify thyroid nodules with malignant cytology (Bethesda VI). Systematic review of the literature contributed 21 studies representing 2036 preoperative specimens. The BRAF p.V600E substitution was detected in 46% to 90% of cases with a pooled positivity rate of 70% (95% confidence intervals: 64%‐76%). None of the studies used comprehensive oncogene panels. Retrospective analysis of 531 clinical specimens evaluated with the next‐generation sequencing ThyGeNEXT Thyroid Oncogene Panel identified a total of 436 gene alterations. BRAF mutation rate was 64% in specimens tested as part of standard clinical care and 75% in specimens from cross‐sectional research studies (P = .022). Testing for additional actionable gene alterations such as TERT promoter mutations or RET and NTRK gene rearrangements further increased the diagnostic yield to 78%‐85% and up to 95% when including the ThyraMIR Thyroid miRNA Classifier. These data support the role of molecular cytopathology in surgical and therapeutic decision‐making and warrant additional studies.

PD1 Blockade Enhances ICAM1-Directed CAR T Therapeutic Efficacy in Advanced Thyroid Cancer

PURPOSE

Advanced thyroid cancers, including poorly differentiated and anaplastic thyroid cancer (ATC), are lethal malignancies with limited treatment options. The majority of patients with ATC have responded poorly to programmed death 1 (PD1) blockade in early clinical trials. There is a need to explore new treatment options.

EXPERIMENTAL DESIGN

We examined the expression of PD-L1 (a ligand of PD1) and intercellular adhesion molecule 1 (ICAM1) in thyroid tumors and ATC cell lines, and investigated the PD1 expression level in peripheral T cells of patients with thyroid cancer. Next, we studied the tumor-targeting efficacy and T-cell dynamics of monotherapy and combination treatments of ICAM1-targeting chimeric antigen receptor (CAR) T cells and anti-PD1 antibody in a xenograft model of ATC.

RESULTS

Advanced thyroid cancers were associated with increased expression of both ICAM1 and PD-L1 in tumors, and elevated PD1 expression in CD8⁺ T cells of circulating blood. The expression of ICAM1 and PD-L1 in ATC lines was regulated by the IFNγ-JAK2 signaling pathway. ICAM1-targeted CAR T cells, produced from either healthy donor or patient T cells, in combination with PD1 blockade demonstrated an improved ability to eradicate ICAM1-expressing target tumor cells compared with CAR T treatment alone. PD1 blockade facilitated clearance of PD-L1 high tumor colonies and curtailed excessive CAR T expansion, resulting in rapid tumor clearance and prolonged survival in a mouse model.

CONCLUSIONS

Targeting two IFNγ-inducible, tumor-associated antigens-ICAM1 and PD-L1-in a complementary manner might be an effective treatment strategy to control advanced thyroid cancers in vivo.

Restructuring of a General Surgery Residency Program in an Epicenter of the Coronavirus Disease 2019 Pandemic: Lessons From New York City

On March 1, 2020, the first case of coronavirus disease 2019 (COVID-19) was confirmed in New York, New York. Since then, the city has emerged as an epicenter for the ongoing pandemic in the US. To meet the anticipated demand caused by the predicted surge of patients with COVID-19, the Department of Surgery at NewYork-Presbyterian Hospital/Weill Cornell Medicine developed and executed an emergent restructuring of general surgery resident teams and educational infrastructure. The restructuring of surgical services described in this Special Communication details the methodology used to safely deploy the necessary amount of the resident workforce to support pandemic efforts while maintaining staffing for emergency surgical care, limiting unnecessary exposure of residents to infection risk, effectively placing residents in critical care units, and maintaining surgical education and board eligibility for the training program as a whole.

Abstract 1895: The role of the IFNγ pathway in the development of vemurafenib resistance in BRAFV600E mutant thyroid carcinoma

BRAFV600E is the most common driver mutation in anaplastic thyroid cancer, and BRAF inhibitors are increasingly being used in the treatment of this disease. However, the therapeutic benefit of BRAFV600E inhibitors, such as vemurafenib, has been limited in thyroid cancer due to rapid development of drug resistance in clinical practice. Here, we characterize a targetable mechanism of vemurafenib resistance by studying vemurafenib-resistant clones derived from BRAFV600E mutant anaplastic thyroid cancer cell lines (8505C and FRO), and propose a drug combination to overcome resistance. Vemurafenib resistance in these established clones was verified by persistent activation of ERK1/2 after vemurafenib treatment by western blot analysis. RNA-sequencing and subsequent ingenuity pathway analysis (IPA) was used to identify differences in pathway activation after vemurafenib treatment in parental and vemurafenib-resistant cell lines. Treatment of parental cells with vemurafenib resulted in differential gene expression correlating with upstream activation of the IFNγ-STAT1-IRF1 pathway (All FDR &lt; 0.05). Furthermore, parental cells treated with vemurafenib demonstrated higher HLA-II and HLA-A2 expression than untreated cells when analyzed by flow cytometry, implying the activation of IFNγ signaling pathway. In the IPA of a vemurafenib-resistant clone (8505C Res1), IFNγ, STAT1 and IRF1 expression was upregulated compared to their respective untreated parental cell line (All FDR &lt; 0.05). Increased IRF1 expression in 8505C Res1 compared to parental cells was also demonstrated by qPCR, supporting innate IFNγ activation in the resistant clone. Inhibition of the IFNγ pathway with increasing concentrations of neutralizing anti-IFNγ antibody sensitized resistant thyroid cancer cells to vemurafenib. Pharmacologically blocking the IFNγ downstream pathway in resistant clones with AZD1480 (JAK2 inhibitor) or fludarabine (STAT1 inhibitor), resulted in decreased cell viability in combination treatment groups compared to vemurafenib treatment only (cell viability: 92% vemurafenib vs 19% fludarabine combination, p &lt; 0.05) (cell viability: 73% vemurafenib vs 37% AZD1480 combination, p &lt; 0.05). These results demonstrate that activation of the IFNγ pathway is a potential mechanism for the development of resistance of anaplastic thyroid cancer to BRAFV600E inhibitors. Our study suggests that blockade of the IFNγ pathway may potentiate the therapeutic benefit of vemurafenib treatment in this disease.

Citation Format: Jessica Limberg, Katherine D. Gray, Mandeep Singh, Timothy M. Ullmann, Brian Wyrwas, Weibin Wang, Zachary Lowenstein, Steve El Eshaky, Heng Liang, Wei Li, Tuo Zhang, Jenny Xiang, Dessislava Stefanova, Rasa Zarnegar, Thomas J. Fahey, Irene M. Min. The role of the IFNγ pathway in the development of vemurafenib resistance in BRAFV600E mutant thyroid carcinoma [abstract]. In: Proceedings of the Annual Meeting of the American Association for Cancer Research 2020; 2020 Apr 27-28 and Jun 22-24. Philadelphia (PA): AACR; Cancer Res 2020;80(16 Suppl):Abstract nr 1895.

Treatment Utilization and Socioeconomic Disparities in the Surgical Management of Gastroparesis

BACKGROUND

Gastroparesis is an end-organ sequela of diabetes. We evaluated the roles of race and socioeconomic status in hospitalization rates and utilization of surgical treatments in these patients.

METHODS

Data was extracted from the National Inpatient Sample (NIS) between the years 2012 and 2014, and any discharge diagnosis of gastroparesis (536.3) was included. Gastrostomy, jejunostomy, and total parenteral nutrition were considered nutritional support procedures, and procedures aimed at improving motility were considered definitive disease-specific procedures: pyloroplasty, endoscopic pyloric dilation, gastric pacemaker placement, and gastrectomy.

RESULTS

There were 747,500 hospitalizations reporting a discharge diagnosis of gastroparesis. On multivariable analysis, black race (OR 1.93, 95% CI 1.89-1.98; p < 0.001) and Medicaid insurance (OR 1.46, 95% CI 1.42-1.50; p < 0.001) were the strongest socioeconomic risk factors for hospitalization due to gastroparesis. Patients in urban teaching institutions were most likely to undergo a surgical intervention for gastroparesis (5.53% of patients versus 3.94% of patients treated in urban non-teaching hospitals and 2.38% of patients in rural hospitals; p < 0.001). Uninsured patients were less than half as likely to receive treatment compared to those with private insurance (OR 0.41, 95% CI 0.34-0.48; p < 0.001), and black patients had an OR 0.75 (95% CI 0.69-0.81; p < 0.001) for receiving treatment. Urban teaching hospitals had a twofold higher likelihood of intervention (OR 2.12, 95% CI 1.84-2.44; p < 0.001).

CONCLUSIONS

Marked racial and economic disparities exist in surgical distribution of care for gastroparesis, potentially driven by differences in utilization of care.

Risk Factors for Prolonged Length of Stay and Readmission After Parathyroidectomy for Renal Secondary Hyperparathyroidism

BACKGROUND

Population-based analyses of 30-day outcomes after parathyroidectomy for renal secondary hyperparathyroidism are limited. We sought to identify risk factors associated with prolonged length of stay (LOS) and readmission in this patient population.

METHODS

Patients with secondary hyperparathyroidism who underwent parathyroidectomy were reviewed in the ACS-NSQIP database (2011-2016). Patients were identified by ICD codes specific to secondary hyperparathyroidism of renal origin and the ACS-NSQIP variable for current preoperative dialysis. Multivariable logistic regression was used to identify independent factors associated with prolonged LOS and 30-day readmission after parathyroidectomy.

RESULTS

The cohort included 1846 patients with secondary hyperparathyroidism on dialysis who underwent parathyroidectomy. There were 416 (22.5%) patients classified under the prolonged LOS group. On multivariable analysis, factors associated with prolonged LOS included elevated preoperative alkaline phosphatase [OR 3.13 (95%-CI 2.09-4.70), p < 0.001], decreased preoperative hematocrit [OR 1.83 (95%-CI 1.25-2.68), p = 0.002], unplanned reoperation (OR 5.02 [95%-CI 2.22-11.3], p < 0.001) and any postoperative complication [OR 6.12 (95%-CI 3.31-11.3), p < 0.001]. The overall 30-day readmission rate was 15.0%. Hypocalcemia and hungry bone syndrome accounted for 47.0% (n = 93/198) of readmissions. On multivariable analysis, patients with a history of hypertension and those undergoing unplanned reoperation were at risk of readmission [2.16 (95%-CI 1.21-3.87), p = 0.009, and 2.40 (95%-CI 1.15-5.02), p = 0.020, respectively], whereas reoperative parathyroidectomy was inversely associated with readmission (OR 0.24, 95%-CI 0.07-0.80, p = 0.021).

CONCLUSION

In patients undergoing parathyroidectomy for renal secondary hyperparathyroidism, several readily available preoperative biochemical markers, including those of increased bone turnover and anemia, are associated with prolonged postoperative LOS. Unplanned reoperation was predictive of both increased LOS and readmission.

Indoleamine 2,3-Dioxygenase-1 Expression in Adrenocortical Carcinoma

BACKGROUND

Indoleamine 2,3-dioxygenase 1 (IDO-1) is overexpressed in many human carcinomas and a successful target for therapy in mouse models. Prognosis of patients with advanced adrenocortical carcinoma (ACC) is poor due to the lack of effective treatments, and new therapies are therefore needed. Herein, we investigate whether IDO-1 is expressed in human ACC tissues.

METHODS

53 tissue samples from patients with ACC, adrenal adenoma (AA), adrenocortical tumors (ACTs), and normal adrenal were identified. Immunohistochemistry was performed on formalin-fixed, paraffin-embedded slides for IDO-1. Samples were scored for cytoplasmic staining as per intensity and the percent of positive cells and for stromal staining by percent of positive cells. Tumor characteristics, PD-L1, PDL-2, and CD-8+ T-lymphocyte expression were also determined.

RESULTS

Samples from 32 ACC, 3 ACT, 15 AA, and 3 normal adrenal were analyzed. IDO-1 was expressed in tumor tissue in 22 of 32 ACC samples, compared with 8 of 15 AA sample (P = 0.344). IDO-1 expression was significantly increased in stromal tissue of ACC samples (16 of 33), compared with AA samples (0 of 15) (P = 0.001). IDO-1 expression in ACC and AA samples was associated with PD-L2 expression (P = 0.034). IDO-1 expression in ACC stromal tissue was associated with CD8+ T-lymphocyte infiltration (P = 0.028).

CONCLUSIONS

IDO-1 is expressed in a majority of ACC samples. Its expression in tumor tissue is associated with PD-L2 expression, and expression in stroma is associated with CD8+ cell infiltration. IDO-1 inhibition, alone or in combination with PD-1 inhibition, could therefore be an interesting target in treatment of ACC.