Transcriptomic-Based Microenvironment Classification Reveals Precision Medicine Strategies for Pancreatic Ductal Adenocarcinoma.

BACKGROUND & AIMS: The complex tumor microenvironment (TME) of pancreatic ductal adenocarcinoma (PDAC) has hindered the development of reliable predictive biomarkers for targeted therapy and immunomodulatory strategies. A comprehensive characterization of the TME is necessary to advance precision therapeutics in PDAC. METHODS: A transcriptomic profiling platform for TME classification based on functional gene signatures was applied to 14 publicly available PDAC datasets (n = 1657) and validated in a clinically annotated independent cohort of patients with PDAC (n = 79). Four distinct subtypes were identified using unsupervised clustering and assessed to evaluate predictive and prognostic utility. RESULTS: TME classification using transcriptomic profiling identified 4 biologically distinct subtypes based on their TME immune composition: immune enriched (IE); immune enriched, fibrotic (IE/F); fibrotic (F); and immune depleted (D). The IE and IE/F subtypes demonstrated a more favorable prognosis and potential for response to immunotherapy compared with the F and D subtypes. Most lung metastases and liver metastases were subtypes IE and D, respectively, indicating the role of clonal phenotype and immune milieu in developing personalized therapeutic strategies. In addition, distinct TMEs with potential therapeutic implications were identified in treatment-naive primary tumors compared with tumors that underwent neoadjuvant therapy. CONCLUSIONS: This novel approach defines a distinct subgroup of PADC patients that may benefit from immunotherapeutic strategies based on their TME subtype and provides a framework to select patients for prospective clinical trials investigating precision immunotherapy in PDAC. Further, the predictive utility and real-world clinical applicability espoused by this transcriptomic-based TME classification approach will accelerate the advancement of precision medicine in PDAC.

The Role of Demographic and Clinical Factors in Germline Mutation Testing for Patients with Primary Hyperparathyroidism.

INTRODUCTION: Guidelines recommending genetic counseling in primary hyperparathyroidism (PHPT) vary. To further delineate current recommendations, this study examined genetic counseling referral patterns and rates of mutations in surgical patients with PHPT. PATIENTS AND METHODS: A single-institution review was performed of adult patients who underwent parathyroidectomy for presumed sporadic PHPT. Genetic testing indications of hypercalcemia onset ≤ 40 years, multigland disease (MGD), family history (FHx) of PHPT, or other clinical indications suspicious for a PHPT-related endocrinopathy were examined by demographics and mutation detection rates. RESULTS: Genetic counseling was performed in 237 (37.9%) of 625 patients. Counseling was discussed but not performed in 121 (19.4%) patients. No evidence was noted of genetic referral discussion in the remaining 267 (42.7%). Of these groups, patients who received genetic counseling were youngest, p < 0.001 [median age 55.3 (IQR 43.2, 66.7) years]. The majority of patients with indications of age ≤ 40 years (65.7%), FHx (78.0%), and other clinical indications (70.7%) underwent genetic counseling, while most with MGD (57.0%) did not. Eight mutations were detected in 227 patients (3.5%). Mutations included: MEN1 (n = 2), CDC-73 (n = 4), and CASR (n = 2). Detection was most common in patients with FHx (4/71, 5.6%), then age ≤ 40 years (3/66, 4.5%), and other clinical indications (3/80, 3.8%). No mutations were identified in 48 patients tested solely for MGD. CONCLUSIONS: Most patients with onset of hypercalcemia age ≤ 40 years, positive FHx, or other clinical concerns underwent genetic counseling, while most with MGD did not. As no germline mutations were identified in patients with MGD alone, further investigation of MGD as a sole indication for genetic counseling may be warranted.

Cosyntropin Stimulation Testing is More Selective than Postoperative Day 1 Basal Cortisol for Diagnosing Secondary Adrenal Insufficiency After Unilateral Adrenalectomy.

BACKGROUND: Secondary adrenal insufficiency (SAI) may occur in patients after unilateral adrenalectomy for adrenal-dependent hypercortisolism (HC) or primary aldosteronism (PA). This study aimed to assess whether postoperative day (POD) 1 basal cortisol was predictive of an abnormal cosyntropin stimulation test (CST) result and the need for glucocorticoid replacement (GR). METHODS: A retrospective review of consecutive patients who underwent unilateral adrenalectomy for HC, PA, or both between September 2014 and September 2022 was performed. On POD1, CST was performed for all the patients with HC, and before 2021 for all the patients with PA. The patients with an abnormal CST result were deemed at risk of SAI and discharged with GR. Receiver operating characteristic (ROC) curves were generated to evaluate the sensitivity (SN) and specificity (SP) of basal cortisol thresholds to predict an abnormal CST result. RESULTS: The patients underwent unilateral adrenalectomy for overt hypercortisolism (OH; n = 42), mild autonomous cortisol excess (MACE; n = 70), mixed PA/HC (n = 22), or PA (n = 73). On POD1, CST was performed for 152 patients (93% OH, 96% MACE,73% PA/HC, 41% PA), and 80 patients (53%) had SAI (67% OH, 55% MACE, 44% PA/HC, 33% PA). The SN and SP of a basal cortisol level of 10 µg/dL or lower to predict an abnormal CST were respectively 92% and 77% for OH, 94% and 73% for MACE, 100% and 85% for PA, and 100% and 67% for PA/HC. The optimal basal cortisol level for predicting an abnormal CST for patients with PA or PA/HC was 5 µg/dL or lower (SN/SP, 100%). CONCLUSIONS: After unilateral adrenalectomy for HC, PA, or mixed PA/HC, POD1 CST improved identification of patients at risk for SAI compared with basal cortisol levels alone. The authors recommend that POD1 CST be performed to determine the risk for SAI and the need for postoperative GR after unilateral adrenalectomy for patients with HC.

Hypercalcemia and Postoperative Joint Symptoms Following Joint Replacement for Osteoarthritis.

INTRODUCTION: Calcium metabolism dysregulation in the setting of primary hyperparathyroidism (PHPT) mediated chondrocalcinosis is implicated in joint pain, a key element in the decision regarding arthroplasty for osteoarthritis. The relationship between hypercalcemia and joint pain, before and after arthroplasty, is unknown. This study investigates the association between preoperative hypercalcemia and postoperative outcomes following total knee (TKA) and total hip arthroplasty (THA). METHODS: A retrospective chart review was conducted on patients who underwent initial elective THA or TKA. Patients with a preoperative serum calcium >10.2 mg/dL were matched (1:2-1:4) with nearest neighbor to patients with normal serum calcium. THA and TKA functional outcomes were measured at baseline and 1-y postoperatively using patient-reported Hip Disability and Osteoarthritis Outcome Scores and Knee Injury and Osteoarthritis Outcome Scores surveys. Postoperative complications, readmissions, length of stay, and functional outcome scores were compared. RESULTS: Four hundred ninety-five patients (106 hypercalcemic cases, 389 matched controls) were included. Of these, 223 patients underwent THA (46 cases; 177 controls) and 272 patients underwent TKA (61 cases; 211 controls). There were no differences in Hip Disability and Osteoarthritis Outcome Scores and Knee Injury and Osteoarthritis Outcome Scores scores, postoperative complications, readmissions, or length of stay between cases and controls. Only 19/106 (18%) hypercalcemic patients had a parathyroid hormone (PTH); of these, 9 (47%) had possible PHPT (PTH > 40). CONCLUSIONS: Patients with hypercalcemia undergoing arthroplasty have similar functional and postoperative outcomes as normocalcemic patients. As PTH was obtained in <20% of hypercalcemic cases and 50% had possible PHPT, we recommend that hypercalcemic patients undergo PHPT workup. Additional investigation is needed to determine the effect of PHPT on arthroplasty outcomes.

Going for Broke: The Impact of Cost of Living on Surgery Resident Stipend Value.

OBJECTIVE: The objective of this study was to provide a direct comparison of first-year general surgery resident stipends across states and major cities, using the Cost-of-Living Index (COLI) to determine stipend value. BACKGROUND: Financial challenges are among residents' top sources of stress, and this may be exacerbated in areas with high costs of living. A 2021 survey found that the mean first-year medical resident stipend increased by 0.6%, or $358, from 2020 to 2021, and only 33% of institutions used cost-of-living to determine annual resident stipend adjustments. METHODS: An American Medical Association database was used to identify accredited general surgery residency programs. The 2021-2022 stipend data for first-year general surgery positions were obtained, then data were grouped by state and major city and averaged. Major cities were defined as cities with >4 programs.A direct comparison of stipends was performed using the COLI. RESULTS: Stipend data were available for 337 of 346 general surgery programs. The national average first-year residency stipend was $60,064±$4233. The average COLI-adjusted stipend was $57,090±$5742, with a value loss of -$3493, or 5%.For major cities, the average stipend was $63,383±$4524, and the average COLI-adjusted stipend was $46,929±$8383, with an average value loss of -$16,454, or 26%. CONCLUSIONS: The financial burdens that residents face cannot be overlooked, and the cost of living has a meaningful impact on resident stipend value. The current Graduate Medical Education compensation structure limits federal and institutional capacity to adjust for the cost of living and creates an insulated market in which residents are under-compensated.

Biliary Adverse Events During Neoadjuvant Therapy for Pancreatic Cancer.

OBJECTIVE: To describe a high-volume experience with biliary drainage before neoadjuvant therapy (NAT) for patients with operable pancreatic cancer (PC) and characterize the association between biliary adverse events (BAEs) and patient outcome. BACKGROUND: Patients with PC presenting with biliary obstruction require durable decompression before NAT. METHODS: Patients with operable PC and tumor-associated biliary obstruction were examined and grouped by the presence or absence of a BAE during NAT. The incidence, timing, and management of BAEs are described, and outcomes, including the completion of all treatment and overall survival (OS), were compared. RESULTS: Of 426 patients who received pretreatment biliary decompression, 92 (22%) experienced at least 1 BAE during NAT, and 56 (13%) required repeat intervention on their biliary stent. The median duration of NAT was 161 days for all patients and was not different in the group that experienced BAEs. The median time from initial stent placement to BAE was 64 days. An interruption in the delivery of NAT (median 7 days) occurred in 25 (6%) of 426 patients. Among 426 patients, 290 (68%) completed all NAT, including surgery: 60 (65%) of 92 patients with BAE and 230 (69%) of 334 patients without BAE ( P =0.51). Among 290 patients who completed NAT and surgery, the median OS was 39 months, 26 months for the 60 patients with BAE, and 43 months for the 230 patients without BAE ( P =0.02). CONCLUSIONS: During extended multimodal NAT for PC, 22% of patients experienced a BAE. Although BAEs were not associated with a significant interruption of treatment, patients who experienced a BAE had worse OS.

An Exosome-based Transcriptomic Signature for Noninvasive, Early Detection of Patients With Pancreatic Ductal Adenocarcinoma: A Multicenter Cohort Study.

BACKGROUND & AIMS: Pancreatic ductal adenocarcinoma (PDAC) incidence is rising worldwide, and most patients present with an unresectable disease at initial diagnosis. Measurement of carbohydrate antigen 19-9 (CA19-9) levels lacks adequate sensitivity and specificity for early detection; hence, there is an unmet need to develop alternate molecular diagnostic biomarkers for PDAC. Emerging evidence suggests that tumor-derived exosomal cargo, particularly micro RNAs (miRNAs), offer an attractive platform for the development of cancer-specific biomarkers. Herein, genomewide profiling in blood specimens was performed to develop an exosome-based transcriptomic signature for noninvasive and early detection of PDAC. METHODS: Small RNA sequencing was undertaken in a cohort of 44 patients with an early-stage PDAC and 57 nondisease controls. Using machine-learning algorithms, a panel of cell-free (cf) and exosomal (exo) miRNAs were prioritized that discriminated patients with PDAC from control subjects. Subsequently, the performance of the biomarkers was trained and validated in independent cohorts (n = 191) using quantitative reverse transcription polymerase chain reaction (qRT-PCR) assays. RESULTS: The sequencing analysis initially identified a panel of 30 overexpressed miRNAs in PDAC. Subsequently using qRT-PCR assays, the panel was reduced to 13 markers (5 cf- and 8 exo-miRNAs), which successfully identified patients with all stages of PDAC (area under the curve [AUC] = 0.98 training cohort; AUC = 0.93 validation cohort); but more importantly, was equally robust for the identification of early-stage PDAC (stages I and II; AUC = 0.93). Furthermore, this transcriptomic signature successfully identified CA19-9 negative cases (<37 U/mL; AUC = 0.96), when analyzed in combination with CA19-9 levels, significantly improved the overall diagnostic accuracy (AUC = 0.99 vs AUC = 0.86 for CA19-9 alone). CONCLUSIONS: In this study, an exosome-based liquid biopsy signature for the noninvasive and robust detection of patients with PDAC was developed.

CA19-9 Response to First-Line Neoadjuvant FOLFIRINOX and Second-Line Gemcitabine/Nab-Paclitaxel for Patients with Operable Pancreatic Cancer.

BACKGROUND: Response to second-line (2L) neoadjuvant therapy for operable pancreatic cancer (PC) is understudied. This study examined carbohydrate antigen 19-9 (CA19-9) response to first-line (1L) and 2L chemotherapy. METHODS: The study identified patients with operable PC and elevated CA19-9 (≥ 35 U/mL with total bilirubin < 2 mg/dL) who received 1L FOLFIRINOX (FFX). The patients were restaged after 2 months and based on response, received additional FFX or gemcitabine/nab-paclitaxel (GnP) as part of total neoadjuvant therapy. Response was defined as a decrease in tumor size on computed tomography (CT) imaging or a decline in CA19-9 of 50% or more and preserved performance status. RESULTS: For operable PC with an elevated CA19-9, 108 patients received 1L FFX. After 2 months of chemotherapy, the decision was made to continue FFX (FFX ≥ FFX) for 76 (70%) of the 108 patients and switch to GnP (FFX ≥ GnP)) for 32 (30%) of the patients. Of the 32 FFX ≥ GnP patients, 27 had no evidence of radiographic or biochemical (CA19-9) response to 1L FFX. Of these 27 patients, 26 (96%) demonstrated a response to 2L GnP. After 4 months of chemotherapy, 62 (82%) of the 76 FFX ≥ FFX patients had a CA19-9 response compared with 31 (97%) of the 32 FFX ≥ GnP patients (p = 0.04). CONCLUSIONS: Lack of biochemical response to 2 months of 1L FFX may identify a subgroup of patients with a very high rate of response to 2L GnP, emphasizing the importance of assessing treatment response at 2-month intervals.

Patterns of Unnecessary Insurer Prior Authorization Denials in a Complex Surgical Oncology Practice.

INTRODUCTION: Insurance prior authorization (PA) is a determination of need, required by a health insurer for an ordered test/procedure. If the test/procedure is denied, a peer-to-peer (P2P) discussion between ordering provider and payer is used to appeal the decision. The objective of this study was to measure the number and patterns of unnecessary PA denials. METHODS: This was a retrospective review at a quaternary cancer center from October 2021 to March 2022. Included were all patients with outpatient imaging orders for surgical planning or surveillance of gastrointestinal, endocrine, or skin cancer. Primary outcome was unnecessary initial denial (UID) defined as an order that required preauthorization, was initially denied by the insurer, and subsequently overturned by P2P. RESULTS: Nine hundred fifty seven orders were placed and 419 required PA (44%). Of tests requiring authorization, 55/419 (13.1%) were denied. Variability in the likelihood of initial denial was seen across insurers, ranging from 0% to 57%. Following P2P, 32/55 were overturned (58.2% UID). The insurers most likely to have a UID were Aetna (100%), Anthem (77.8%), and Cigna (50.0%). UID was most common for gastrointestinal (58.9%) and endocrine (58.3%) cancers. Average P2P was 33.5 min (interquartile range 28-40). CONCLUSIONS: The majority of imaging studies initially denied were overturned after P2P. If all UIDs were eliminated, this would represent 108 less P2P discussions with an estimated time-savings of 60.3 h annually within a high-volume surgical oncology practice. Combined personnel costs to the health systems and stress on patients with cancer due to image-associated PAs and P2P appear hard to justify.

Neoadjuvant chemotherapy for pancreatic cancer: Quality over quantity.

BACKGROUND AND OBJECTIVES: The ideal duration of neoadjuvant chemotherapy (NACT) in patients with localized pancreatic adenocarcinoma (PDAC) treated with curative intent is unclear. We sought to determine the prognostic significance of both duration of NACT and Carbohydrate Antigen 19-9 (CA19-9) normalization to NACT. METHODS: We examined patients with resectable and borderline resectable PDAC treated with NACT and chemoradiation. Patients were compared by NACT duration (2 vs. 4 months) and by CA19-9 normalization after NACT. RESULTS: Among 171 patients, 83 (49%) received 2 months of NACT, and 88 (51%) received 4 months. After NACT completion, 115 (67%) patients had persistently elevated CA19-9, and 56 (33%) had normalized. Of the 125 patients who had successful surgery, 73 (58%) had normalized CA19-9 postoperatively. Duration of NACT was not associated with overall survival (OS) while CA19-9 normalization after NACT (regardless of duration) was associated with improved OS (hazard ratio [HR] 0.56, 95% confidence interval [CI] 0.35-0.89, p = 0.02). Adjuvant chemotherapy was associated with improved OS among patients without CA19-9 normalization after NACT (HR 0.42, CI 0.20-0.86, p = 0.02) but not among those that normalized, independent of duration. CONCLUSIONS: CA19-9 normalization after NACT is a clinically significant endpoint of treatment; patients without CA19-9 normalization may benefit from additional therapy.

Updates and new directions in the use of radiation therapy for the treatment of pancreatic adenocarcinoma: dose, sensitization, and novel technology.

Panc reatic ductal adenocarcinoma (PDAC) is a devastating malignancy. There have been few advances that have substantially improved overall survival in the past several years. On its current trajectory, the deaths from PDAC are expected to cross that from all gastrointestinal cancers combined by 2030. Radiation therapy is a technically very complex modality that bridges multiple different treatment strategies. It represents a hybrid among advanced diagnostic imaging, local (often ablative) intervention, and heterogeneous biological mechanisms contributing to normal and oncologic cell kill. In this article, we bring an overview of the several promising strategies that are currently being investigated to improve outcomes using radiation therapy for patients with PDAC.

Identification of Serum miRNA Signature and Establishment of a Nomogram for Risk Stratification in Patients With Pancreatic Ductal Adenocarcinoma.

OBJECTIVE: The aim of the study was to perform mRNA-miRNA regulatory network analyses to identify a miRNA panel for molecular subtype identification and stratification of high-risk patients with pancreatic ductal adenocarcinoma (PDAC). BACKGROUND: Recent transcriptional profiling effort in PDAC has led to the identification of molecular subtypes that associate with poor survival; however, their clinical significance for risk stratification in patients with PDAC has been challenging. METHODS: By performing a systematic analysis in The Cancer Genome Atlas and International Cancer Genome Consortium cohorts, we discovered a panel of miRNAs that associated with squamous and other poor molecular subtypes in PDAC. Subsequently, we used logistic regression analysis to develop models for risk stratification and Cox proportional hazard analysis to determine survival prediction probability of this signature in multiple cohorts of 433 patients with PDAC, including a tissue cohort (n = 199) and a preoperative serum cohort (n = 51). RESULTS: We identified a panel of 9 miRNAs that were significantly upregulated (miR-205-5p and -934) or downregulated (miR-192-5p, 194-5p, 194-3p, 215-5p, 375-3p, 552-3p, and 1251-5p) in PDAC molecular subtypes with poor survival [squamous, area under the receiver operating characteristic curve (AUC) = 0.90; basal, AUC = 0.89; and quasimesenchymal, AUC = 0.83]. The validation of this miRNA panel in a tissue clinical cohort was a significant predictor of overall survival (hazard ratio = 2.48, P < 0.0001), and this predictive accuracy improved further in a risk nomogram which included key clinicopathological factors. Finally, we were able to successfully translate this miRNA predictive signature into a liquid biopsy-based assay in preoperative serum specimens from PDAC patients (hazard ratio: 2.85, P = 0.02). CONCLUSION: We report a novel miRNA risk-stratification signature that can be used as a noninvasive assay for the identification of high-risk patients and potential disease monitoring in patients with PDAC.

Pancreatobiliary Maljunction-associated Gallbladder Cancer Is as Common in the West, Shows Distinct Clinicopathologic Characteristics and Offers an Invaluable Model for Anatomy-induced Reflux-associated Physio-chemical Carcinogenesis.

OBJECTIVE: To determine the associations of pancreatobiliary maljunction (PBM) in the West. BACKGROUND: PBM (anomalous union of common bile duct and pancreatic duct) is mostly regarded as an Asian-only disorder, with 200X risk of gallbladder cancer (GBc), attributed to reflux of pancreatic enzymes. Methods: Radiologic images of 840 patients in the US who underwent pancreatobiliary resections were reviewed for PBM and contrasted with 171 GBC cases from Japan. RESULTS: Eight % of the US GBCs (24/300) had PBM (similar to Japan; 15/ 171, 8.8%), in addition to 1/42 bile duct carcinomas and 5/33 choledochal cysts. None of the 30 PBM cases from the US had been diagnosed as PBM in the original work-up. PBM was not found in other pancreatobiliary disorders. Clinicopathologic features of the 39 PBM-associated GBCs (US:24, Japan:15) were similar; however, comparison with non-PBM GBCs revealed that they occurred predominantly in females (F/M = 3); at younger (<50-year-old) age (21% vs 6.5% in non-PBM GBCs; P = 0.01); were uncommonly associated with gallstones (14% vs 58%; P < 0.001); had higher rate of tumor-infiltrating lymphocytes (69% vs 44%; P = 0.04); arose more often through adenoma-carcinoma sequence (31% vs 12%; P = 0.02); and had a higher proportion of nonconventional carcinomas (21% vs 7%; P = 0.03). Conclusions: PBM accounts for 8% of GBCs also in the West but is typically undiagnosed. PBM-GBCs tend to manifest in younger age and often through adenoma-carcinoma sequence, leading to unusual carcinoma types. If PBM is encountered, cholecystectomy and surveillance of bile ducts is warranted. PBM-associated GBCs offer an invaluable model for variant anatomy-induced chemical (reflux-related) carcinogenesis.

Pancreatic ductal adenocarcinomas associated with intraductal papillary mucinous neoplasms (IPMNs) versus pseudo-IPMNs: relative frequency, clinicopathologic characteristics and differential diagnosis.

The literature is highly conflicted on what percentage of pancreatic ductal adenocarcinomas (PDACs) arise in association with intraductal papillary mucinous neoplasms (IPMNs). Some studies have claimed that even small (Sendai-negative) IPMNs frequently lead to PDAC. Recently, more refined pathologic definitions for mucin-lined cysts were provided in consensus manuscripts, but so far there is no systematic analysis regarding the frequency and clinicopathologic characteristics of IPMN-mimickers, i.e., pseudo-IPMNs. In this study, as the first step in establishing frequency, we performed a systematic review of the pathologic findings in 501 consecutive ordinary PDACs, which disclosed that 10% of PDACs had associated cysts ≥1 cm. While 31 (6.2%) of these were IPMN or mucinous cystic neoplasm (MCN), 19 (3.8%) were other cyst types that mimicked IPMN (pseudo-IPMNs) per recent WHO/consensus criteria. As the second step of the study, we performed a comparative clinicopathologic analysis by also including our entire surgical pathology/consultation databases that was comprised of 60 IPMN-associated PDACs, 30 MCN-associated PDACs and 40 pseudo-IPMN-associated PDACs. We found that 84% of true IPMNs were pre-operatively recognized, whereas IPMN was considered in differential diagnosis of 33% of pseudo-IPMNs. Of the 40 pseudo-IPMNs, there were 15 secondary duct ectasias; 6 large-duct-type PDACs; 5 pseudocysts; 5 cystic tumor necrosis; 4 simple mucinous cysts; 3 groove pancreatitis-associated paraduodenal wall cysts; and 2 congenital cysts. Microscopically, pseudo-IPMNs had at least partial mucinous-lining mimicking IPMN but had smaller cystic (mean = 1.9 cm) and larger PDAC (mean = 3.8 cm) components compared to true IPMNs (cyst = 5.7 cm; PDAC = 2.0 cm). In summary, in this pathologically verified analysis that utilized refined criteria, 10% of PDACs were discovered to have cysts ≥1 cm, about two-thirds of which were IPMN/MCN but about one-third were pseudo-IPMNs. True IPMNs underlying the PDACs are often large and are already diagnosed pre-operatively as having an IPMN component, whereas only a third of the pseudo-IPMNs receive IPMN diagnosis by imaging and their cysts are smaller. At the histopathologic level, pseudo-IPMNs are highly prone to misdiagnosis as IPMN, which presumably accounts for much higher association of IPMNs with PDAC as reported in some studies. The subtle but salient characteristics of pseudo-IPMNs elucidated in this study should be combined with careful radiological/clinical correlation in order to exclude pseudo-IPMNs.

The Clinical Utility of Preoperative Thyroglobulin for Surgical Decision Making in Thyroid Disease.

BACKGROUND: Serum thyroglobulin (Tg) levels are used to monitor for differentiated thyroid cancer (DTC) recurrence and have been correlated with posttreatment disease burden. The clinical significance of Tg in the preoperative setting to predict the risk of DTC is unclear. Our aim is to examine the clinical utility of preoperative Tg levels in those undergoing thyroidectomies for DTC or benign disease. MATERIALS AND METHODS: From a prospectively collected database, we identified 385 patients who underwent thyroidectomy from 01/14 to 12/19 and had preoperative Tg levels available. Preoperative Tg levels were compared by preoperative indication for surgery, Bethesda category of biopsied nodules, presence of DTC on surgical pathology, and number of metastatic lymph nodes. RESULTS: There was no difference in mean preoperative Tg level when comparing indication for surgery (P = 0.2) or Bethesda classification (P = 0.4). Mean preoperative Tg levels were lower in patients with DTC (238 ± 77) compared to without DTC (532 ± 97) on final pathology (P = 0.02). Among 188 DTC patients who had lymph nodes removed, there was no significant correlation between the preoperative Tg level and number of positive lymph nodes on final pathology (P = 0.4). CONCLUSIONS: Preoperative serum Tg levels were lower in patients with DTC compared to those with benign disease on final pathology and did not correlate with extent of lymph node metastasis in patients with DTC. We found that serum Tg levels obtained in the preoperative setting do not predict DTC or lymph node metastasis and, therefore, do not inform the extent of surgery for differentiated thyroid cancer.

Wide Variability in Catecholamine Levels From Adrenal Venous Sampling in Primary Aldosteronism.

INTRODUCTION: While adrenal venous sampling (AVS) differentiates between the unilateral and bilateral disease in patients with primary aldosteronism (PA), it is unknown if AVS can determine laterality of pheochromocytoma in patients with bilateral adrenal masses. This study analyzes adrenal vein (AV) epinephrine and norepinephrine levels in nonpheochromocytoma patients to determine the "normal" range. MATERIALS AND METHODS: We reviewed patients who underwent AVS for PA between 2009 and 2019 at a single institution; pheochromocytoma was excluded. Aldosterone, cortisol, epinephrine, and norepinephrine levels were obtained from the inferior vena cava (IVC), left adrenal vein (LAV), and right adrenal vein (RAV). Successful AV cannulation was defined by an AV/IVC cortisol ratio of ≥3:1 or an AV epinephrine level ≥364 pg/mL. Plasma measurements (pg/mL) are median values with interquartile ranges; normal ranges for epinephrine and norepinephrine are 10-200 pg/mL and 80-520 pg/mL, respectively. RESULTS: AVS was performed in 172 patients in 405 AVs (173 LAV and 232 RAV). Median epinephrine levels were IVC = 19 (14 and 34), LAV = 3811 (1870 and 6915), and RAV = 2897 (1500 and 5288). Median norepinephrine levels were IVC = 325 (186 and 479), LAV = 1450 (896 and 2050), and RAV = 786 (436 and 1582). There was a difference between LAV and RAV epinephrine levels (P = 0.024) and between LAV and RAV norepinephrine (P = 0.002) levels. CONCLUSIONS: This extensive experience with AVS demonstrated a wide range of "normal" AV catecholamine levels in patients without pheochromocytoma, which suggests that the utility of AVS to determine disease laterality in patients with pheochromocytoma and bilateral adrenal nodules is likely to be limited.

Lessons learned from investigator-initiated clinical trials for localized pancreatic cancer.

Investigator-initiated trials (IITs) are clinical trials in which the clinician is both the sponsor and the investigator. IITs have also been developed to test strategies designed to optimize existing therapies or treatment approaches that may not be supported by industry sponsors or may be too novel to gain the consensus to be supported by cooperative groups. The role of the investigator is comprehensive and includes protocol development, securing funding for the administration of the trial, recruitment and monitoring of subjects, and assurance for the protection of human subjects. We will briefly review the importance of surgeons in developing IITs and provide insights into logistical barriers from conception to completion of the trial.

Utility of Epinephrine Levels in Determining Adrenal Vein Cannulation During Adrenal Venous Sampling for Primary Aldosteronism.

OBJECTIVE: In patients with primary aldosteronism, adrenal venous sampling (AVS) is performed to determine the presence of unilateral or bilateral adrenal disease. During AVS, verification of catheter positioning within the left adrenal vein (AV) and the right AV by comparison of AV and inferior vena cava (IVC) cortisol levels can be variable. The objective of this study was to determine the utility of AV epinephrine levels in assessing successful AV cannulation. METHODS: This was a single institution, retrospective review of patients who underwent AVS with cosyntropin stimulation for primary aldosteronism between 2009 and 2018. Successful cannulation of the AV was defined by an AV/IVC cortisol ratio selectivity index (SI) ≥3:1. Epinephrine thresholds to predict catheter placement in the AV were determined using logistic regression. The calculated epinephrine thresholds were compared with previously published thresholds. RESULTS: AVS was performed on 101 consecutive patients and, based on the SI, successful cannulation of the left AV and right AV occurred in 98 (97%) and 91(90%) patients, respectively. The calculated optimal epinephrine threshold to predict AV cannulation was 364 pg/mL (sensitivity, 92.1%; specificity, 94.6%) and the calculated optimal AV/IVC epinephrine ratio threshold was 27.4, (sensitivity, 92.1%; specificity, 91.3%). Among the 14 patients with failed AV cannulation, 3 patients would have been considered to have successful AVS using AV epinephrine levels >364 pg/mL and AV/IVC epinephrine ratio >27.4 thresholds. CONCLUSION: Obtaining 2 right AV samples routinely as well as AV and IVC epinephrine levels during AVS could prevent unnecessary repeat AVS in patients with failed AV cannulation based on cortisol-based SI <3:1.

Variation in parathyroid adenoma size in patients with sporadic, primary hyperparathyroidism: small gland size does not preclude single gland disease.

PURPOSE: Small, abnormal parathyroid glands are usually associated with multigland hyperplasia in patients with primary hyperparathyroidism (pHPT). The purpose of this study was to determine the association between parathyroid adenoma size and biochemical cure rates in patients undergoing single gland parathyroidectomy. METHODS: The study included patients with sporadic pHPT who underwent initial parathyroidectomy and met intraoperative PTH criteria for cure after resection of a single adenoma (SGD). Patients were divided into quartiles (Q1 = smallest) based on gland weight and maximum dimension; cure rates were compared across groups. RESULTS: A single parathyroid adenoma was removed in 517 patients, with a median gland weight of 500 mg (range 50-11890). Median maximum gland dimension was 15 mm (range 5-55). With median follow-up of 28 months (range 6-81), the biochemical cure rate was 97.1%. There was no difference in cure rate by gland weight (Q1 94.6%, Q2 96.9%, Q3 98.4%, Q4 98.5%, p = 0.217) or maximum gland dimension (Q1 95.6%, Q2 97.6%, Q3 97.1%, Q4 98.2%, p = 0.641). When Q1 patients (by gland weight) were divided by quartile, there was no difference in cure rates (93.1% [50-140 mg]; 95.2% [150-190 mg]; 97.1% [200-230 mg]; 93.3% [240-280 mg]; p = 0.665). CONCLUSION: For patients with pHPT who underwent single gland parathyroidectomy, there was no difference in cure rates by gland weight or maximum dimension. These data suggest that the removal of parathyroid adenomas as small as 50 mg with an appropriate decline in ioPTH likely represent single gland disease and additional exploration may not be necessary.

Validation of a Cost-effective Cast Saw Simulation-based Educational Module to Improve Cast Removal Safety.

BACKGROUND: Inexperience in cast removal in the pediatric population can lead to a range of cast saw-related injuries. The purpose of this study is to validate a simple simulation-based wax model that is both reproducible and economical while providing a valuable tool that can be used to grade cast saw use performance in trainees. METHODS: Cylindrical wax models were used as an analog for a pediatric upper extremity. The wax models were casted in a proscribed reproducible fashion for consistency. Two groups, the first consisting of 15 experienced cast saw users and the second consisting of 15 inexperienced individuals, completed 4 sequential longitudinal cuts in the casted wax models. After removal of the cast material, marks left by the cast saw in the wax were counted and measured. Indentation length, maximum depth, and maximum width were measured on each wax model. The total length of the cast saw indentations per cast saw user was also calculated. RESULTS: For the inexperienced cast saw users, the average total length of the cast saw indentations was 526.56 mm, average maximum depth was 1.91 mm, and average maximum width was 3.24 mm. For experienced cast saw users, the average total length of the cast saw indentations was 156.57 mm with an average maximum depth of 1.06 mm and average maximum width of 2.19 mm. Receiver operating characteristic curves of the total number of errors, total error length, maximum error depth, and maximum error width show effective discrimination of experienced from inexperienced trainees. CONCLUSIONS: This study provides valid evidence supporting a cost-effective, time-efficient, and easily reproducible educational simulation module that can objectively measure cast saw the performance in trainees. This model demonstrates construct validity and can distinguish novice from experienced cast saw users. It is sensitive enough to identify mistakes even in the most experienced cast saw users, creating a platform that can provide performance-based feedback to cast saw users of all experience levels. LEVEL OF EVIDENCE: Level III-diagnostic test.