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.

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.

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.

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.

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.

Does Aggressive Variant Histology Without Invasive Features Predict Overall Survival in Papillary Thyroid Cancer?: A National Cancer Database Analysis.

OBJECTIVE: We aimed to clarify whether aggressive histology of papillary thyroid cancer (PTC) impacts overall survival (OS). SUMMARY BACKGROUND DATA: Aggressive variants of PTC (AVPTC) are associated with invasive features. However, their behavior in the absence of these features is not well characterized. METHODS: Patients treated from 2004 to 2015 for classic PTC (cPTC) or AVPTCs were identified from the National Cancer Database. Patients were further stratified based on presence of at least 1 invasive feature-extrathyroidal extension, multifocality, lymphovascular invasion, nodal or distant metastasis. Demographics, treatments, and OS were compared. RESULTS: A total of 170,778 patients were included-162,827 cPTC and 7951 AVPTC. Invasive features were more prevalent in AVPTC lesions compared to cPTC (70.7% vs 59.7%, P < 0.001). AVPTC included tall cell/columnar cell (89.5%) and diffuse sclerosing (10.5%) variants. Patients with invasive features had worse OS irrespective of histology. Furthermore, when controlling for demographics, tumor size, and treatment variables in patients with noninvasive lesions, AVPTC histology alone was not associated with worse OS compared to cPTC (P = 0.209). In contrast, among patients who had at least 1 invasive feature, AVPTC histology was independently predictive of worse OS (P < 0.05) {TCV/Columnar hazard ratio [HR] 1.2; [95% confidence interval (CI) 1.1-1.3] and diffuse sclerosing HR 1.3; 95% CI 1.0-1.7]}. All invasive features, except multifocality, were independently associated with worse OS, with metastasis being the most predictive [HR 2.9 (95% CI 2.6-3.2) P < 0.001]. CONCLUSIONS: In the absence of invasive features, AVPTC histology has similar OS compared to cPTC. In contrast, diffuse sclerosing and tall cell/columnar variants are associated with worse OS when invasive features are present.

The Use and Benefit of Adjuvant Radiotherapy in Parathyroid Carcinoma: A National Cancer Database Analysis.

BACKGROUND: The routine use of external beam radiotherapy (EBRT) is not recommended for parathyroid carcinoma (PC). However, case series have demonstrated a potential benefit in preventing local recurrence with EBRT. We aimed to characterize the patient population treated with EBRT and identify any impact of EBRT on overall survival (OS) in parathyroid carcinoma. METHODS: Patients who underwent surgery for PC from 2004 to 2016 were identified from the National Cancer Database. Clinicopathologic variables and OS were compared between patients based on treatment with EBRT. Multivariable logistic and Cox regression models were performed with propensity scores and inverse-probability-weighting (IPW) adjustment to reduce treatment-selection bias in the OS analysis. RESULTS: A total of 885 patients met the inclusion criteria, with 126 (14.2%) undergoing EBRT. Demographics were similar between the two cohorts (EBRT vs. no EBRT). However, patients treated with EBRT had a higher frequency of regionally extensive disease, nodal metastases, and residual microscopic disease (all p < 0.05). On multivariable analysis, Black race, regional tumor extension, nodal metastasis, and treatment at an urban facility were independently associated with EBRT. The 5-year OS was 85.3% with a median follow-up of 60.8 months. EBRT was not associated with a difference in OS in crude, multivariable, or IPW models. More importantly, 10.5% of patients with completely resected localized disease (M0, N0 or Nx) underwent EBRT without a benefit in OS (p = 0.183). CONCLUSIONS: EBRT is not associated with any survival benefit in the treatment of PC. Therefore, it may be overutilized, particularly in patients with localized disease and complete surgical resection.

Not all laparoscopic adrenalectomies are equal: analysis of postoperative outcomes based on tumor functionality.

BACKGROUND: Laparoscopic adrenalectomy is known to have a low complication rate; however, the influence of functional tumor subtype on postoperative outcomes is not well defined. METHODS: Patients undergoing laparoscopic adrenalectomy for benign adrenal tumors between 2009 and 2017 were selected from the American College of Surgeons National Surgical Quality Improvement Program (NSQIP) database. Patient demographics, postoperative outcomes, and length of stay were compared between tumor subtypes. RESULTS: A total of 3946 patients underwent a laparoscopic adrenalectomy during the study period; 3214 (81.5%) were performed for non-functional adenomas, and 732 (18.6%) for functional tumors-467 (64%) aldosteronomas, 184 (25%) cortisol-producing adenomas, and 81 (11%) pheochromocytomas. The risk of any complication was highest for patients with Cushing's (6.5%) and lowest with Conn's syndrome (1.1%) compared to other lesions (3.7% pheochromocytoma, 5.3% adenoma, p < 0.001). Among the patients with functional tumors, those with cortisol-producing adenomas had the highest rates of both deep surgical site infection (1.6%, p = 0.026) and urinary tract infection (2.2%, p = 0.029), whereas myocardial infarction was most prevalent in patients with pheochromocytoma (2.5%, p = 0.012). When adjusted for demographic differences, BMI, and comorbidity scores, no tumor type was associated with increased complication rate; instead aldosteronoma (vs. benign adenoma) was independently predictive of fewer adverse events [0.3 (95% CI 0.1-0.7), p = 0.004] and a shorter length of hospital stay [0.6 (95% CI 0.4-0.8), p = 0.001]. The overall mortality rate was low at 0.4%, although significantly higher in Cushing's patients (2.2%, p = 0.015). CONCLUSIONS: Laparoscopic adrenalectomy is a safe operation with low mortality and complication rates. However, postoperative risks differ between tumor subtype, so patients should be counseled accordingly.

Quantifying Factors Essential to the Integrity of the Esophagogastric Junction During Antireflux Procedures.

OBJECTIVE: To quantify the contribution of key steps in antireflux surgery on compliance of the EGJ. BACKGROUND: The lower esophageal sphincter and crural diaphragm constitute the intrinsic and extrinsic sphincters of the EGJ, respectively. Interventions to treat reflux attempt to restore the integrity of the EGJ. However, there are limited data on the relative contribution of critical steps during antireflux procedures to the functional integrity of the EGJ. METHODS: Primary antireflux surgery was performed on 100 consecutive patients with pathologic reflux. Intraoperative EGJ measurements including distensibility index (DI), cross-sectional area (CSA), and HPZ length were collected using EndoFLIP. Data was acquired pre-repair, post-diaphragmatic re-approximation with sub-diaphragmatic EGJ relocation, and post-sphincter augmentation. RESULTS: Patients underwent Nissen (45%), Toupet (44%), or LINX (11%). After diaphragmatic re-approximation, DI decreased by a median 0.77 mm2/mm Hg [95%-confidence interval (CI): -0.99, -0.58; P < 0.0001], CSA decreased 16.0 mm2 (95%-CI: -20.0, -8.0; P < 0.0001), whereas HPZ length increased 0.5 cm (95%-CI: 0.5, 1.0; P < 0.0001). After sphincter augmentation, DI decreased 0.14 mm2/mm Hg (95%-CI: -0.30, -0.04; P = 0.0005) and CSA decreased 5.0 mm2 (95%-CI: -10.0, 1.0; P = 0.0.0015), whereas HPZ length increased 0.5 cm (95%-CI: 0.50, 0.54; P < 0.0001). Diaphragmatic re-approximation had a higher percent contribution to distensibility (79% vs 21%), CSA (82% vs 18%), and HPZ (60% vs 40%) than sphincter augmentation. CONCLUSION: Dynamic intraoperative monitoring demonstrates that diaphragmatic re-approximation and sub-diaphragmatic relocation has a greater effect on EGJ compliance than sphincter augmentation. As such, antireflux procedures should address both for optimal improvement of EGJ physiology.

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.

Does the ATA Risk Stratification Apply to Patients with Papillary Thyroid Microcarcinoma?

BACKGROUND: The incidence of papillary thyroid microcarcinoma (PTMC) has increased over the past decade. The American Thyroid Association (ATA) suggests that these patients may undergo either thyroid lobectomy or active surveillance. It remains unclear whether there exists a subgroup of PTMC patients who may benefit from more aggressive treatment due to increased risk of recurrence. METHODS: We retrospectively reviewed 357 patients with PTMC who underwent surgery at a single institution from 2004 to 2016. Patients were classified according to 2015 ATA risk stratification for structural disease recurrence. Demographic, oncologic, and clinicopathologic data were compared between groups. RESULTS: Out of 357 patients, 246 were classified as low-risk PTMC, 93 were intermediate-risk, and 18 were high-risk. There were more male patients in the high-risk group (38.9%) than the intermediate- (31.2%) or low-risk groups (15.4%) (p < 0.001). Patients with low-risk microcarcinomas were more likely to have an incidental PTMC when compared to intermediate- or high-risk groups (98[39.8%], 15[16.1%], 1[5.6%], respectively, p < 0.001). Patients with high-risk PTMCs, compared to those with intermediate- and low-risk PTMCs, were more likely to have rising postoperative thyroglobulin levels after total thyroidectomy (6[40.0%], 4[5.1%], 9[5.7%], respectively, p = 0.001) and structural recurrence after lobectomy or total thyroidectomy (3[16.7%], 0[0%], 0[0%], respectively, p < 0.001). The median follow-up time was 17.5 (IQR 3-55) months. CONCLUSIONS: Patients with high-risk PTMC have an increased risk of recurrence when compared to low- and intermediate-risk microcarcinomas, whereas intermediate-risk PTMC may behave similarly to low-risk tumors. ATA risk stratification may inform clinical decision making for patients with PTMC.

Prognostic Characteristics of Primary Squamous Cell Carcinoma of the Thyroid: A National Cancer Database Analysis.

BACKGROUND: Primary squamous cell carcinoma of the thyroid (ThySCC) is a rare cancer, primarily described only in case reports. We aimed to characterize the prognosis of ThySCC and compare its oncologic behavior to other thyroid malignancies. METHODS: The National Cancer Database was queried to identify patients with ThySCC, papillary, tall cell variant, poorly differentiated (PDTC), and anaplastic (ATC) subtypes of thyroid cancer treated from 2004 to 2015. Demographics, tumor characteristics, and treatments were compared by tumor type and assessed to identify independent predictors of overall survival (OS). RESULTS: Of 123,684 patients included, 314 had ThySCC. ThySCC patients had a 5-year OS of 17.7%, more closely resembling ATC (8.3%) than PDTC or PTC. ThySCC and ATC patients had similar demographics, except ThySCC patients who were younger (68.0 vs. 70.2 years, p < 0.01). ThySCC tumors were smaller (mean 53.5 ± 45.7 vs. 69.5 ± 75.2 mm) with less frequent extrathyroidal extension (ETE) (64.0% vs. 73.8%), lymphovascular invasion (8.3% vs. 12.3%), and positive margins (22.0% vs. 28.3%) compared to ATCs (p < 0.05). ETE [HR 3.1 (95% CI 1.5-6.4), p < 0.05] and lymph node metastases [HR 2.2 (95% CI 1.2-4.0) p < 0.05] were independently associated with worse OS for ThySCC patients. Both ThySCC and ATC patients had similar surgical success rates, with R1 resection possible in 37.3% versus 35.0% of patients, respectively (p < 0.05). However, in contrast to ATC patients, adjuvant therapy was not associated with improved OS for ThySCC patients after complete resection. CONCLUSIONS: ThySCC has a poor prognosis, similar to ATC, but with fewer aggressive features and no apparent survival benefit with adjuvant therapy after complete macroscopic surgical resection.

Laparoscopic Adrenalectomy Has the Same Operative Risk as Routine Laparoscopic Cholecystectomy.

BACKGROUND: Laparoscopic adrenalectomy (LA) is the treatment of choice for aldosteronomas and other adrenal tumors. Despite evidence that surgical cure of aldosteronomas is superior to medical treatment, reluctance remains to refer patients for LA. Here we compared the safety profile of LA to laparoscopic cholecystectomy (LC), a commonly performed laparoscopic procedure. MATERIALS AND METHODS: Patients undergoing LA or LC from 2012 to 2015 were selected from the National Surgical Quality Improvement Program. Patients who had an LA for an adrenal adenoma or aldosteronoma were compared to those who had LC for biliary colic or cholelithiasis. Multivariable logistic regressions were used to analyze postoperative outcomes between the two groups, controlling for patient factors. RESULTS: A total of 19,315 patients met inclusion criteria (n = 1458 LA, n = 17,857 LC). Patients undergoing an LA were older (median 53 versus 46 y old, P < 0.001), with a higher rate of American Society of Anesthesiologists score ≥3 (65.6% versus 25.0%, P < 0.001) and modified frailty index score ≥ 1 (78.5% versus 33.6%, P < 0.001). Overall mortality was 0.1% with no difference between the two cohorts (P = 0.426). Incidence of at least one postoperative complication was higher in the LA cohort (3.6% versus 2.2%, P < 0.001). However, when adjusting for demographics, comorbidities, and operative time, adrenalectomy was not associated with an increased risk of postoperative complications (OR 0.83 (0.6-1.2), P = 0.268). CONCLUSIONS: After comparing postoperative outcomes between patients undergoing LA and LC, operation type was not independently associated with an increased incidence of complications. Therefore, physicians should consider LA as having a similar overall risk profile to LC when deciding whether to refer patients to surgery.

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.

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.

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.

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.

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.

Impact of multikinase inhibitor approval on survival and physician practice patterns in advanced or metastatic medullary thyroid carcinoma.

BACKGROUND: This study aimed to identify whether multikinase inhibitor approval for medullary thyroid carcinoma was associated with changes in systemic therapy administration or overall survival. METHODS: The National Cancer Database was queried for advanced medullary thyroid carcinoma patients. Clinicopathologic comparisons were performed between premultikinase inhibitor (2005-2010) and postmultikinase inhibitor (2011-2016) approval groups. Multivariable logistic and Cox regressions were applied to assess predictors of systemic therapy and overall survival. RESULTS: A total of 2,891 patients met the criteria. Postmultikinase inhibitor patients were less likely to undergo radiation (P = .02) and more likely to receive systemic therapy (P = .01). The rate of systemic therapy nearly doubled from 2010 to 2011 (8.1% to 13.8%, P = .04); it subsequently declined back toward preapproval rates. Before multikinase inhibitor approval, only metastases and radiation were associated with systemic therapy (P < .05). After multikinase inhibitor approval, patients with small tumors, extrathyroidal extension, positive lymph nodes, or metastases were more likely to receive systemic therapy (P < .05). The 5-year overall survival between pre and postmultikinase inhibitor groups, for those who received systemic therapy (n = 288), was similar (P = .58), even when restricted to patients with distant metastases (P = .55). CONCLUSION: After approval of multikinase inhibitors, physicians broadened the criteria for systemic therapy. Prescription rates have since declined. Given the toxicities of these drugs and no improvement in overall survival since introduction, selective utilization may be warranted.