Impact of Obesity on Risk of Hypocalcemia After Total Thyroidectomy: Targeted National Surgical Quality Improvement Program Analysis of 16,277 Patients.

INTRODUCTION: Hypocalcemia following total thyroidectomy (TT) is common due to postoperative parathyroid dysfunction and vitamin D deficiency. Given the association between obesity and vitamin D deficiency, we sought to correlate body mass index (BMI) with hypocalcemia after TT. METHODS: Patients undergoing TT between 2016 and 2020 were identified from the American College of Surgeons National Surgical Quality Improvement Program thyroidectomy-targeted database. Univariable and multivariable regressions, stratified by BMI category (normal, overweight, obese), identified factors associated with hypocalcemia prior to discharge, within 30 d, and severe hypocalcemic events (emergent evaluation, intravenous calcium supplementation, or readmission). RESULTS: Sixteen thousand two hundred seventy seven TT were performed with available BMI data. Three thousand five hundred thirty one (21.7%) patients had normal BMI, 4823 (29.6%) were overweight, and 7772 (47.7%) were obese. Patients with BMI ≥ 25 had decreased risk of hypocalcemia before discharge (9.8% versus 13%, odds ratio [OR] 0.73, P < 0.001), 30 d (8.1% versus 10.4%, OR 0.76, P < 0.001), and severe hypocalcemic events (5.5% versus 6.4%, OR 0.84, P = 0.029) compared to normal BMI patients. On multivariable analysis for normal BMI patients, age < 45 y was a risk factor for hypocalcemia before discharge, 30 d, and severe hypocalcemic events (P < 0.05 for all). Additional risk factors in this group for 30-d hypocalcemia included parathyroid autotransplant and central neck dissection (P < 0.05) and recurrent laryngeal nerve injury for severe hypocalcemic events (P = 0.01). CONCLUSIONS: Younger patients with BMI < 25 are at an increased risk for hypocalcemia and severe hypocalcemic events after TT. These patients may benefit from preoperative counseling and increased calcium/vitamin D supplementation to reduce prolonged hospitalization and mitigate morbidity.

Survival After Adrenalectomy for Metastatic Lung Cancer.

BACKGROUND: Adrenal metastasectomy is associated with increased survival in non-small cell lung cancer (NSCLC) with isolated adrenal metastases. Although clinical use of adrenal metastasectomy has expanded, indications remain poorly defined. The aim of this study was to evaluate the clinical benefit of adrenal metastasectomy for all lung cancer subtypes. PATIENTS AND METHODS: We performed a retrospective cohort study of patients who underwent adrenal metastasectomy for metastatic lung cancer at six institutions between 2001 and 2015. The primary outcomes were disease-free survival (DFS) and overall survival (OS). Cox proportional hazards regressions and Kaplan-Meier survival analysis were performed. RESULTS: For 122 patients, the mean age was 60.5 years and 49.2% were female. Median time to detection of the metastasis was 11 months, and 41.8% were ipsilateral to the primary lung cancer. Median DFS was 40 months (1 year: 64.8%; 5 year: 42.9%). Factors associated with longer DFS included primary tumor resection [hazard ratio (HR): 0.001; p = 0.005], longer time to adrenal metastasis (HR: 0.94; p = 0.005), and ipsilateral metastases (HR: 0.13; p = 0.004). Shorter DFS corresponded with older age (HR: 1.11; p = 0.01), R1 resection (HR: 8.94; p = 0.01), adjuvant radiation (HR: 9.45; p = 0.02), and open adrenal metastasectomy (HR: 10.0; p = 0.03). Median OS was 47 months (1 year: 80.2%; 5 year: 35.2%). Longer OS was associated with ipsilateral metastasis (HR: 0.55; p = 0.02) and adjuvant chemotherapy (HR: 0.35; p = 0.02). Shorter OS was associated with extra-adrenal metastases at adrenalectomy (HR: 3.52; p = 0.007), small cell histology (HR: 15.0; p = 0.04), and lung radiation (HR: 3.37; p = 0.002). DISCUSSION: Durable survival was observed in patients undergoing adrenal metastasectomy and should be considered for isolated adrenal metastases of NSCLC. Small cell histology and extra-adrenal metastases are relative contraindications to adrenal metastasectomy.

Increased Body Mass Index is Associated With Lower Risk of Hypocalcemia in Total Thyroidectomy Patients.

INTRODUCTION: Hypocalcemia following total thyroidectomy is common due to postoperative parathyroid dysfunction. We sought to identify the impact of obesity on postthyroidectomy hypocalcemia. METHODS: We performed a single-center retrospective study of all total thyroidectomies performed from 2016 to 2019 after implementation of an updated calcium supplementation protocol. Patient characteristics and outcomes were measured including body mass index (BMI), postoperative hypocalcemia (Ca <8.3), and hypocalcemic symptoms. RESULTS: Overall, 559 total thyroidectomies were performed. A total of 146 patients (26.2%) developed hypocalcemia requiring supplementation adjustment and 116 patients (20.8%) developed mild hypocalcemia symptoms. On multivariable analysis, younger patients, patients with lower preoperative calcium, and lower BMI were more likely to develop postoperative hypocalcemia (all P < 0.05). Similarly, younger patients and patients with BMI <25 were more likely to develop hypocalcemic symptoms (all P < 0.05). CONCLUSIONS: Younger age and lower BMI were associated with increased risk of hypocalcemia after total thyroidectomy. These patients may benefit from preoperative and/or increased postoperative supplementation.

Adrenalectomy for Secondary Malignancy: Patients, Outcomes, and Indications.

OBJECTIVE: The goal of this study was to examine a multi-institutional experience with adrenal metastases to describe survival outcomes and identify subpopulations who benefit from adrenal metastasectomy. BACKGROUND: Adrenalectomy for metastatic disease is well-described, although indications and outcomes are incompletely defined. METHODS: A retrospective cohort study was performed of patients undergoing adrenalectomy for secondary malignancy (2002-2015) at 6 institutions. The primary outcomes were disease free survival (DFS) and overall survival (OS). Analysis methods included Kaplan-Meier and Cox proportional hazards. RESULTS: Of 269 patients, mean age was 60.1 years; 50% were male. The most common primary malignancies were lung (n = 125, 47%), renal cell (n = 38, 14%), melanoma (n = 33, 12%), sarcoma (n = 18, 7%), and colorectal (n = 12, 5%). The median time to detection of adrenal metastasis after initial diagnosis of the primary tumor was 17 months (interquartile range: 6-41). Post-adrenalectomy, the median DFS was 18 months (1-year DFS: 54%, 5-year DFS: 31%). On multivariable analysis, lung primary was associated with longer DFS [hazard ratio (HR): 0.49, P = 0.008). Extra-adrenal oligometastatic disease at initial presentation (HR: 1.84, P = 0.016), larger tumor size (HR: 1.07, P = 0.013), chemotherapy as treatment of the primary tumor (HR: 2.07 P = 0.027) and adjuvant chemotherapy (HR: 1.95, P = 0.009) were associated with shorter DFS. Median OS was 53 months (1-year OS: 83%, 5-year OS: 43%). On multivariable analysis, extra-adrenal oligometastatic disease at adrenalectomy (HR: 1.74, P = 0.031), and incomplete resection of adrenal metastasis (R1 margins; HR: 1.62, P = 0.034; R2 margins; HR: 5.45, P = 0.002) were associated with shorter OS. CONCLUSIONS: Durable survival is observed in patients undergoing adrenal metastasectomy and should be considered for subjects with isolated adrenal metastases.

Completion Thyroidectomy is Less Common Following Updated 2015 American Thyroid Association Guidelines.

BACKGROUND: The 2015 American Thyroid Association (ATA) guidelines recommended that low-risk, differentiated thyroid cancers (DTC) between 1 and 4 cm may be treated with thyroid lobectomy alone. We sought to determine the effect of these guideline changes on the rate of completion thyroidectomy (CT) for low-risk DTC and factors influencing surgical decision-making. METHODS: All patients from 2014 to 2018 who received an initial thyroid lobectomy at our institution with final pathology demonstrating DTC were included. Patients were divided into "pre" and "post" guideline cohorts (2014-2015 and 2016-2018, respectively). The rate of CT was compared between the two cohorts. Patient demographics and tumor characteristics were examined for association with CT. RESULTS: A total of 163 patients met study criteria: 63 patients in the 2014-2015 ("pre") and 100 in the 2016-2018 ("post") group. In the "pre" period, 41 (65.1%) patients received CT compared with 43 (43.0%) in the "post" period (p < 0.01)-a 34% decrease in the rate of completion surgery (p < 0.01). Of low-risk patients with DTC between 1 and 4 cm in size, 17 of 35 (48.6%) received CT in the "pre" period compared with 15 of 60 (25.0%) in the post period-a 48.6% decrease in the rate of completion surgery (p = 0.02). Greater tumor size, capsular invasion, and multifocality were associated with CT in low-risk "post" guideline patients (p < 0.05 for all). CONCLUSIONS: The rate of CT decreased significantly by 48.6% for low-risk patients with DTC between 1 and 4 cm, demonstrating recognition of the 2015 ATA guidelines. However, 25% of these patients underwent CT, suggesting additional factors influencing the decision for further treatment.

Diabetes mellitus and hyperglycemia are associated with inferior oncologic outcomes in adrenocortical carcinoma.

PURPOSE: Prior literature suggests that cancer patients with hyperglycemia and type 2 diabetes mellitus (DM) exhibit worse oncologic and overall outcomes. Tumor metabolism and anabolism pathophysiology may explain this association, although this has not been adequately studied in adrenocortical carcinoma (ACC). We hypothesized that DM would be associated with worse oncological outcomes in ACC, and we utilized data from a national database and institutional sources for multimodal analysis. METHODS: Both a multi-institutional database (the Collaborative Endocrine Surgery Quality Improvement Program or CESQIP) and a single-center longitudinal cohort (Dana Farber Cancer Institute or DFCI) were queried as unique retrospective cohorts to identify patients with ACC. Patient demographics, tumor characteristics, DM-specific variables, and oncologic outcome data were assessed. Results were analyzed via univariate analysis and multivariable linear regression analysis. Statistical significance was defined as p < 0.05. RESULTS: Forty-eight CESQIP patients met inclusion criteria; 16 (33.0%) had DM. DM patients had a higher frequency of recurrence on longitudinal follow-up (12.5% v 0.0%, p = 0.04). Persistent disease was observed in 68.8% of DM patients and 40.6% of non-DM patients (p = 0.06). Patients in the DFCI cohort with lower average glucose values (< 110 mg/dL) had a significant survival benefit (p < .0001). A mean serum glucose > 110 mg/dL had increased risk (HR 36.3, 95% confidence interval 1.6, 831.3) for all-cause mortality. CONCLUSIONS: This multi-institutional, multimodal analysis suggests that patients with DM have worse oncologic and overall outcomes for ACC. While further study is warranted, consideration should be given among clinicians to optimize glycemic control as part of their ACC management.

A potential diagnostic pitfall for hobnail variant of papillary thyroid carcinoma.

AIMS: Hobnail variant of papillary thyroid carcinoma (PTC) is an aggressive PTC subtype characterised by a hobnail cytomorphology. However, some classic PTC have a 'hobnail-like' cytomorphology associated with thick, hyalinised, variably oedematous fibrovascular cores that appears to be a form of ischaemic/degenerative atypia. METHODS AND RESULTS: We studied three cohorts to compare the histopathological characteristics and clinical outcome of 'hobnail-like' classic PTC and true hobnail variant of PTC: cohort 1, PTC consecutively resected between 2016 and 2017 (to assess frequency of 'hobnail-like' cytomorphology); cohort 2, 20 'hobnail-like' classic PTC resected between 2005 and 2007 (to assess clinical outcome); and cohort 3, seven true hobnail variant of PTC. A 'hobnail-like' cytomorphology was identified in 16% of consecutively resected PTC. Compared with true hobnail variant, 'hobnail-like' classic PTC occurred in younger patients (mean age 40 years versus 68 years, P < 0.001), were smaller tumours (mean tumour size 2.1 cm versus 4.4 cm, P < 0.001), had a lower rate of gross extrathyroidal extension (0% versus 71%, P < 0.001), had a lower proliferative rate (≥3 mitoses per 10 high-power fields seen in 0% versus 71%, P < 0.001; Ki67 index ≥5% in 0% versus 86%, P < 0.001), a lower rate of secondary pathogenic mutations (for cases with molecular data, 0% versus 100%, P = 0.0061) and improved survival (for cases with sufficient clinical outcome data, 10-year disease-free survival of 93% versus 0%, P = 0.0016). CONCLUSION: Classic PTC can show ischaemic/degenerative atypia that mimics the hobnail cytomorphology of true hobnail variant; however, these tumours lack aggressive histopathological features and pursue an indolent clinical course.

Effect of Noninvasive Follicular Thyroid Neoplasm with Papillary-Like Nuclear Features (NIFTP) on Malignancy Rates in Thyroid Nodules: How to Counsel Patients on Extent of Surgery.

PURPOSE: To investigate the impact of the nomenclature change to "noninvasive follicular thyroid neoplasm with papillary-like nuclear features" (NIFTP) on reported malignancy rates following thyroidectomy. METHODS: Retrospective cohort study of patients with thyroid nodules sampled preoperatively with fine-needle aspiration (FNA) and subsequently removed at one tertiary-care hospital from 4/2016 to 2/2017. Surgical procedure, anatomic pathology, thyroid cytopathology classification, and demographic characteristics were recorded. RESULTS: Thyroidectomy was performed in 353 patients. Twenty-six patients (7.3%) had NIFTP on anatomic pathology. Preoperative FNA demonstrated atypia of undetermined significance (AUS/Bethesda III) in 13 (50%), suspicious for malignancy (SUS/Bethesda V) in 6 (23%), suspicious for follicular neoplasm (SFN/Bethesda IV) in 4 (15%), benign/Bethesda I in 2 (8%), and malignant/Bethesda VI in 1 (4%). Invasive malignancy rates across cytologic categories changed as follows: benign (n = 74) from 4 to 1%, AUS (n = 85) from 33 to 18% (p < 0.05), SFN (n = 58) from 29 to 22%, SUS (n = 33) from 91 to 73% (p < 0.05), and malignant (n = 99) from 99 to 98%. Overall decrease in invasive malignancy was 7.3% for the entire population and 13.1% for indeterminate preoperative FNA cytology (Bethesda III-V). Among 26 NIFTP patients, 17 had thyroid lobectomy (TL) and 9 underwent total thyroidectomy (TT). Eight of the nine patients with TT could have been definitively treated with TL, an 89% decrease. CONCLUSIONS: The NIFTP nomenclature change led to an overall decrease in the malignancy rate at our institution, especially for Bethesda III-V categories. Patients may be counseled toward more conservative surgical options if NIFTP is in the differential.

The Posterior Adiposity Index: A Quantitative Selection Tool for Adrenalectomy Approach.

BACKGROUND: Objective criteria are lacking to determine whether a laparoscopic transabdominal (LA) or retroperitoneoscopic (RP) approach to adrenalectomy is optimal. We hypothesized that imaging characteristics could predict patients for whom RP adrenalectomy is the optimal approach. MATERIALS AND METHODS: Retrospective cohort study of all patients undergoing minimally invasive adrenalectomy between 2014 and 2016 (n = 113) at one institution. Imaging measurements included distances between the skin and Gerota's fascia (S-GF), upper borders of adrenal and kidney (A-K), adrenal and 12th rib (A-R), 12th rib and iliac crest (R-IC), and perinephric fat (PNF). These characteristics plus patient body mass index, gender, age, tumor size, and diagnosis were compared with operative time and estimated blood loss using Pearson's correlation or ANOVA. Multivariable linear regression also identified independent predictors of operative time. RESULTS: Half of patients underwent LA (n = 57) and RP adrenalectomy (n = 56). Median age was 57 y; 60% were female. Mean tumor size was 3.2 cm. Higher body mass index patients were more likely to undergo LA (P = 0.03). Increasing lesion size modestly correlated with longer operative time (r = 0.341). On bivariate analysis, S-GF and PNF distances moderately correlated with operative time (r = 0.464 and 0.494) for RP procedures. The sum of S-GF and PNF generated a Posterior Adiposity Index (PAI). The PAI strongly correlated with operative time for RP (r = 0.590). Nothing was significantly associated with estimated blood loss. Multivariate analysis revealed larger lesions (P = 0.025) and increasing PAI (P = 0.019) were predictive of longer operative time, with PAI ≥9 conferring the greatest risk (P = 0.004). CONCLUSIONS: Smaller tumors and PAI <9 are associated with shorter operative times in RP adrenalectomy. Surgeons can utilize preoperative images to calculate the PAI and determine whether an RP approach would be favorable.

4D-CT is Superior to Ultrasound and Sestamibi for Localizing Recurrent Parathyroid Disease.

BACKGROUND: Recurrent primary hyperparathyroidism (PHPT) presents a diagnostic challenge in localizing a hyperfunctioning gland. Although several imaging modalities are available for preoperative localization, 4D-CT is increasingly utilized for its ability to locate both smaller and previously unlocalized lesions. Currently, there is a paucity of data evaluating the utility of 4D-CT in the reoperative setting compared with ultrasound (US) and sestamibi. We aimed to determine the sensitivity of 4D-CT in localizing parathyroid adenomas in recurrent or persistent PHPT. METHODS: We performed a retrospective review of prospectively collected data from a tertiary-care hospital, and identified 58 patients who received preoperative 4D-CT with US and/or sestamibi between May 2008 and March 2016. Data regarding the size, shape, and number of parathyroid lesions were collected for each patient. RESULTS: A total of 62 lesions were identified intraoperatively among the 58 patients (6 with multigland disease) included in this investigation. 4D-CT missed 13 lesions identified intraoperatively, compared with 32 and 22 lesions missed by US and sestamibi, respectively. Sensitivity for correct lateralization of culprit lesions was 77.4% for 4D-CT, 38.5% for US, and 46% for sestamibi. 4D-CT was superior in lateralizing adenomas (49/62) compared with US (20/52; p < 0.001) and sestamibi (18/47; p < 0.001). The overall cure rate (6-month postoperative calcium < 10.7 mg/dL) was 89.7%. All patients with lesions correctly lateralized by 4D-CT were cured at 6 months. CONCLUSION: 4D-CT localized parathyroid adenomas with higher sensitivity among patients with recurrent or persistent PHPT compared with sestamibi or US-based imaging.

Reasons Associated with Total Thyroidectomy as Initial Surgical Management of an Indeterminate Thyroid Nodule.

BACKGROUND: Diagnostic hemithyroidectomy (HT) is the most widely recommended surgical procedure for a nodule with indeterminate cytology; however, additional details may make initial total thyroidectomy (TT) preferable. We sought to identify patient-specific factors (PSFs) associated with initial TT in patients with indeterminate thyroid nodules. METHODS: Retrospective analysis of all patients with a thyroid nodule ≥ 1 cm and initial cytology of atypia of undetermined significance or suspicious for follicular neoplasm between 2012 and 2015 who underwent thyroidectomy. Medical records were reviewed for patient demographics, neck symptoms, nodule size, cytology, molecular test results, final histopathology, and additional PSFs influencing surgical management. Variables were analyzed to determine associations with the use of initial TT. Logistic regression analyses were performed to identify independent associations. RESULTS: Of 325 included patients, 182/325 (56.0%) had HT and 143/325 (44.0%) had TT. While patient age and sex, nodule size, and cytology result were not associated with initial treatment, five PSFs were associated with initial TT (p < 0.0001). These included contralateral nodules, hypothyroidism, fluorodeoxyglucose avidity on positron emission tomography scan, family history of thyroid cancer, and increased surgical risk. At least one PSF was present in 126/143 (88.1%) TT patients versus 47/182 (25.8%) HT patients (p < 0.0001). Multivariate logistic regression analysis demonstrated that these variables were the strongest independent predictor of TT (odds ratio 45.93, 95% confidence interval 18.80-112.23, p < 0.001). CONCLUSIONS: When surgical management of an indeterminate cytology thyroid nodule was performed, several PSFs were associated with a preference by surgeons and patients for initial TT, which may be useful to consider in making decisions on initial operative extent.

Nonoperative, Active Surveillance of Larger Malignant and Suspicious Thyroid Nodules.

CONTEXT: Active surveillance for papillary thyroid cancer (PTC) meeting criteria for surgical resection is uncommon. Which patients may prove reasonable candidates for this approach is not well defined. OBJECTIVE: This work aimed to examine the feasibility and safety of active surveillance for patients with known or suspected intrathyroidal PTC up to 4 cm in diameter. METHODS: A retrospective review was conducted of all consecutive patients who underwent nonoperative active surveillance of suspicious or malignant thyroid nodules over a 20-year period from 2001 to 2021. We included patients with an initial ultrasound-fine-needle aspiration confirming either (a) Bethesda 5 or 6 cytology or (b) a "suspicious" Afirma molecular test. The primary outcomes and measures included the rate of adverse oncologic outcomes (mortality and recurrence), as well as the cumulative incidence of size/volume growth. RESULTS: Sixty-nine patients were followed with active surveillance for 1 year or longer (average 55 months), with 26 patients (38%) having nodules 2 cm or larger. No patients were found to develop new-incident occurrence of lymph node or distant metastasis. One patient, however, demonstrated concern for progression to a dedifferentiated cancer on repeat core biopsy 17 years after initial start of nonoperative selection. A total of 21% of patients had an increase in maximum diameter more than 3 mm, while volume increase of 50% or greater was noted in 25% of patients. Thirteen patients ultimately underwent delayed (rescue) surgery, and no disease recurrence was noted after such treatment. Age and initial nodule size were not predictors of nodule growth. CONCLUSION: These data expand consideration of active surveillance of PTC in select patients with intrathyroidal suspected malignancy greater than 1 cm in diameter. Rescue surgery, if required at a later time point, appears effective.

Bilateral neck exploration decreases operative time compared to minimally invasive parathyroidectomy in patients with discordant imaging.

BACKGROUND: Unilateral parathyroidectomy for primary hyperparathyroidism (PHPT) has a high success rate in patients with concordant imaging by sestamibi and ultrasound. However, the optimal procedure when imaging is discordant remains controversial; therefore we compared unilateral exploration with intraoperative parathyroid hormone (IOPTH) monitoring to bilateral neck exploration without IOPTH monitoring in patients with discordant localization studies. METHODS: We conducted a retrospective study of 324 consecutive patients with PHPT treated at our institution from October 2005 to September 2009. We collected information regarding imaging, localization site, procedure performed, operative time, and calcium/PTH measurements. RESULTS: Of the 324 patients in the study, 79 (24 %) had discordant imaging by sestamibi and ultrasound. Of these, 62 patients (78 %) underwent bilateral neck exploration without IOPTH monitoring, and 14 patients (18 %) had unilateral exploration with IOPTH monitoring. IOPTH monitoring during unilateral exploration correctly predicted removal of single adenomas in 10/14 patients (71 %) and altered operative management in 4/14 cases (29 %), resulting in conversion to bilateral neck exploration. Operative time for unilateral exploration with IOPTH [median time: 96 min (range: 51-153 min)] was significantly increased relative to bilateral exploration [median time: 52 min (range: 28-149 min)]; p = 0.0027. We identified single-gland disease in 53/76 patients (70 %), double adenomas in 13/76 patients (17 %), and multiglandular hyperplasia in 10/76 patients (13 %). There was no difference in cure rate between these two surgical approaches (p = 1.0) CONCLUSIONS: In contrast with prior studies, we found that operative time for unilateral exploration with IOPTH was significantly increased compared to bilateral neck exploration. In patients with discordant imaging, IOPTH is a useful adjunct in limiting exploration to a single side despite a high false negative rate.

B-Raf(V600E) and thrombospondin-1 promote thyroid cancer progression.

Although B-Raf(V600E) is the most common somatic mutation in papillary thyroid carcinoma (PTC), how it induces tumor aggressiveness is not fully understood. Using gene set enrichment analysis and in vitro and in vivo functional studies, we identified and validated a B-Raf(V600E) gene set signature associated with tumor progression in PTCs. An independent cohort of B-Raf(V600E)-positive PTCs showed significantly higher expression levels of many extracellular matrix genes compared with controls. We performed extensive in vitro and in vivo validations on thrombospondin-1 (TSP-1), because it has been previously shown to be important in the regulation of tumor angiogenesis and metastasis and is present in abundance in tumor stroma. Knockdown of B-Raf(V600E) resulted in TSP-1 down-regulation and a reduction of adhesion and migration/invasion of human thyroid cancer cells. Knockdown of TSP-1 resulted in a similar phenotype. B-Raf(V600E) cells in which either B-Raf(V600E) or TSP-1 were knocked down were implanted orthotopically into the thyroids of immunocompromised mice, resulting in significant reduction in tumor size and fewer pulmonary metastases from the primary carcinoma as compared with the control cells. Treatment of orthotopic thyroid tumors, initiated 1 week after tumor cell implantation with PLX4720, an orally available selective inhibitor of B-Raf(V600E), caused a significant tumor growth delay and decreased distant metastases, without evidence of toxicity. In conclusion, B-Raf(V600E) plays an important role in PTC progression through genes (i.e., TSP-1) important in tumor invasion and metastasis. Testing of a patient's thyroid cancer for B-Raf(V600E) will yield important information about potential tumor aggressiveness and also allow for future use of targeted therapies with selective B-Raf(V600E) inhibitors, such as PLX4720.

Higher SUVmax on FDG-PET is associated with shorter survival in adrenocortical carcinoma.

BACKGROUND: Adrenocortical carcinoma (ACC) is an aggressive, rare malignancy. 2-deoxy-2-[18F]-fluoro-d-glucose positron emission tomography (FDG-PET) assesses tumor metabolism and glucose utilization. We hypothesized that higher maximum standard uptake value (SUVmax) is associated with decreased survival. METHODS: We performed a retrospective analysis of patients with ACC. Included patients (n = 26) had an FDG-PET scan available with a documentable SUVmax. Patients were dichotomized into "High" (≥8.4, n = 12) and "Low" (<8.4, n = 14) SUVmax. Univariate analysis and survival analysis were performed to compare groups. RESULTS: Demographics between groups were equivalent. The high SUVmax cohort demonstrated lower survival (median 479 days or 15.7 months) compared to the low group (median 1490 days or 48.6 months, p = .01). Log-Rank curve confirmed differences in survival (p = .007). CONCLUSIONS: Higher SUVmax was associated with significantly worse survival in ACC and may reflect a more aggressive phenotype. FDG-PET may provide clinically useful information to determine prognosis and treatment. Further studies should prospectively evaluate using FDG-PET/CT in ACC.

Additional Oncogenic Alterations in RAS-Driven Differentiated Thyroid Cancers Associate with Worse Clinicopathologic Outcomes.

PURPOSE: RAS mutations occur across the spectrum of thyroid neoplasms, and more tools are needed for better prognostication. The objective of this study was to evaluate how additional genetic events affecting key genes modify prognosis in patients with RAS-mutant thyroid cancers, and specifically differentiated thyroid cancers (DTC). EXPERIMENTAL DESIGN: We performed a clinical-genomic analysis of consecutive patients with DTC, poorly differentiated (PDTC), or anaplastic thyroid cancer (ATC) between January 2014 and December 2021, in whom a custom-targeted next-generation sequencing assay was performed. Patients harboring RAS mutations were included, and we compared their clinical features and outcomes based upon the presence of additional oncogenic alterations. RESULTS: Seventy-eight patients were identified, with 22% (17/78) harboring a driver RAS mutation plus an additional oncogenic alteration. All six (100%) ATCs had an additional mutation. Compared with DTCs harboring a solitary RAS mutation, patients with DTC with RAS and additional mutation(s) were more likely to be classified as American Thyroid Association high-risk of recurrence (77% vs. 12%; P < 0.001) and to have larger primary tumors (4.7 vs. 2.5 cm; P = 0.002) and advanced stage (III or IV) at presentation (67% vs. 3%; P < 0.001). Importantly, over an average 65-month follow-up, DTC-specific-mortality was more than 10-fold higher (20% vs. 1.8%; P = 0.011) when additional mutations were identified. CONCLUSIONS: Identification of key additional mutations in patients with RAS-mutant thyroid cancers confers a more aggressive phenotype, increases mortality risk in DTC, and can explain the diversity of RAS-mutated thyroid neoplasia. These data support genomic profiling of DTCs to inform prognosis and clinical decision-making.

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.

Effect of Lactate Export Inhibition on Anaplastic Thyroid Cancer Growth and Metabolism.

BACKGROUND: Anaplastic thyroid cancer (ATC) is an aggressive malignancy without effective treatments. ATC cells demonstrate upregulated glycolysis (Warburg effect), generating lactate that is subsequently exported by monocarboxylate transporter 4 (MCT4). This study aims to determine whether MCT4 inhibition can suppress ATC growth. STUDY DESIGN: ATC cell lines 8505C, JL30, and TCO1 were grown in low (3 mmol/L; LG) or high (25 mmol/L; HG) glucose medium containing the lactate shuttle inhibitors acriflavine (10-25 µmol/L; ACF), syrosingopine (100 µmol/L; SYR), or AZD3965 (20 µmol/L; AZD). Lactate level and cell proliferation were measured with standard assays. Seahorse analysis was performed to determine glycolytic response. RESULTS: Compared with HG, addition of ACF to LG decreased lactate secretion for both 8505C (p < 10-5) and JL30 (p < 10-4) cells, whereas proliferation was also reduced (p < 10-4 and 10-5, respectively). During Seahorse analysis, addition of oligomycin increased acidification by 84 mpH/min in HG vs 10 mpH/min in LG containing ACF (p < 10-5). Treatment with LG and SYR drastically diminished 8505C and TCO1 growth vs HG (p < 0.01 for both). LG and AZD treatment also led to reduced proliferation in tested cell lines (p ≤ 0.01 for all) that was further decreased by addition of ACF (p < 10-4 vs HG, p ≤ 0.01 vs LG and AZD). CONCLUSION: Inhibition of lactate shuttles significantly reduced proliferation and glycolytic capacity of ATC cells in a low-glucose environment. Targeting suppression of glycolytic and lactate processing pathways may represent an effective treatment strategy for ATC.

Glycolytic inhibition with 3-bromopyruvate suppresses tumor growth and improves survival in a murine model of anaplastic thyroid cancer.

BACKGROUND: Anaplastic thyroid cancer is a rare but devastating malignancy. Anaplastic thyroid cancer cells exhibit the Warburg effect by preferentially undergoing glycolysis even in aerobic conditions, leading to high glucose use. Here we assess if targeted inhibition of glycolysis can diminish anaplastic thyroid cancer growth and improve outcomes. METHODS: Human anaplastic thyroid cancer cell line 8505C was grown in medium containing high (25 mmol/L) or low (3 mmol/L) glucose concentration and hexokinase II inhibitor 3-bromopyruvate (200 µM). Cellular proliferation, migration, and invasion were measured. An orthotopic xenograft model of anaplastic thyroid cancer was generated in nude mice using 8505C cells. Animals were provided standard chow or a ketogenic diet and treated with 3-bromopyruvate (1.8 mg/kg). Overall survival time was monitored. Necropsies were performed to harvest tumors for analysis. RESULTS: Growth of 8505C in low-glucose medium with 3-bromopyruvate decreased cell proliferation by 89%, migration by 44%, and invasion by 73% (P < .001 for all) compared with high glucose. Animals concomitantly receiving a ketogenic diet and 3-bromopyruvate exhibited smaller tumor volumes (P = .03), slower tumor growth rates (P = .01), and improved overall survival (P = .006) compared with standard-diet control subjects. Monotherapy with a ketogenic diet or 3-bromopyruvate alone did not reduce tumor size or increase survival over the standard-diet control group. CONCLUSION: Glycolytic inhibition with 3-bromopyruvate inhibits tumor growth and extends survival in a murine model of anaplastic thyroid cancer when combined with the ketogenic diet. Thus, targeted glycolytic inhibition of anaplastic thyroid cancer exhibits context-specific utility and may only be effective during ketosis induced by dietary restriction of glycolytic inputs.

Targeting BRAFV600E with PLX4720 displays potent antimigratory and anti-invasive activity in preclinical models of human thyroid cancer.

PURPOSE: B-Raf(V600E) may play a role in the progression from papillary thyroid cancer to anaplastic thyroid cancer (ATC). We tested the effects of a highly selective B-Raf(V600E) inhibitor, PLX4720, on proliferation, migration, and invasion both in human thyroid cancer cell lines (8505c(B-RafV600E) and TPC-1(RET/PTC-1 and wild-type B-Raf)) and in primary human normal thyroid (NT) follicular cells engineered with or without B-Raf(V600E). EXPERIMENTAL DESIGN: Large-scale genotyping analysis by mass spectrometry was performed in order to analyze >900 gene mutations. Cell proliferation and migration/invasion were performed upon PLX4720 treatment in 8505c, TPC-1, and NT cells. Orthotopic implantation of either 8505c or TPC-1 cells into the thyroid of severe combined immunodeficient mice was performed. Gene validations were performed by quantitative polymerase chain reaction and immunohistochemistry. RESULTS: We found that PLX4720 reduced in vitro cell proliferation and migration and invasion of 8505c cells, causing early downregulation of genes involved in tumor progression. PLX4720-treated NT cells overexpressing B-Raf(V600E) (heterozygous wild-type B-Raf/B-Raf(V600E)) showed significantly lower cell proliferation, migration, and invasion. PLX4720 treatment did not block cell invasion in TPC-1 cells with wild-type B-Raf, which showed very low and delayed in vivo tumor growth. In vivo, PLX4720 treatment of 8505c orthotopic thyroid tumors inhibited tumor aggressiveness and significantly upregulated the thyroid differentiation markers thyroid transcription factor 1 and paired box gene 8. CONCLUSIONS: Here, we have shown that PLX4720 preferentially inhibits migration and invasion of B-Raf(V600E) thyroid cancer cells and tumor aggressiveness. Normal thyroid cells were generated to be heterozygous for wild-type B-Raf/B-Raf(V600E), mimicking the condition found in most human thyroid cancers. PLX4720 was effective in reducing cell proliferation, migration, and invasion in this heterozygous model. PLX4720 therapy should be tested and considered for a phase I study for the treatment of patients with B-Raf(V600E) ATC.