Clinicopathologic and Prognostic Features of Pediatric Follicular Cell-derived Thyroid Carcinomas: A Retrospective Study of 222 Patients.

Pediatric thyroid carcinomas (TCs) are rare and mainly approached based on data extrapolated from adults. We retrospectively reviewed 222 pediatric TCs (patient age less than or equal to 21 y). Lymph node (LN) disease volume at presentation was considered high if the largest positive LN measured ≥1 cm and/or >5 LNs were positive. High-grade follicular cell-derived thyroid carcinoma (HGFCTC) were defined by the presence of marked mitotic count and/or tumor necrosis and considered as high-risk histology along with papillary thyroid carcinomas (PTC) diffuse sclerosing variant (DSV). Disease-free survival (DFS) was analyzed. LN involvement at presentation was significantly associated with male sex, larger tumor size, lymphatic invasion, positive surgical margins, and distant metastases at presentation. Five- and 10-year DFS was 84% and 77%, respectively. Only 1 patient with HGFCTC died of disease. Within PTC variants, PTC-DSV was associated with adverse histopathologic parameters and higher regional disease spread, unlike PTC tall cell variant which did not portend worse behavior. The presence of necrosis conferred worse DFS ( P =0.006), while increased mitotic activity did not. While the entire HGFCTC group did not correlate with outcome ( P =0.071), HGFCTC with necrosis imparted worse DFS ( P =0.006). When restricted to PTC-DSV and HGFCTC with necrosis, high-risk histologic classification emerged as an independent prognostic parameter of DFS ( P =0.020). The excellent prognosis of pediatric TCs differs from that of adult TCs showing similar histologic features. While neither increased mitotic activity nor PTC tall cell variant histology predict adverse outcome, PTC-DSV and tumors with necrosis constitute high-risk histologic variants with an increased risk of protracted disease.

NATIONAL SURVEY OF ENDOCRINOLOGISTS AND SURGEONS REGARDING ACTIVE SURVEILLANCE FOR LOW-RISK PAPILLARY THYROID CANCER.

OBJECTIVE: Active surveillance for low-risk papillary thyroid cancer (PTC) was endorsed by the American Thyroid Association guidelines in 2015. The attitudes and beliefs of physicians treating thyroid cancer regarding the active surveillance approach are not known. METHODS: A national survey of endocrinologists and surgeons treating thyroid cancer was conducted from August to September 2017 via professional society emails. This mixed-methods analysis reported attitudes toward potential factors impacting decision-making regarding active surveillance, beliefs about barriers and facilitators of its use, and reasons why physicians would pick a given management strategy for themselves if they were diagnosed with a low-risk PTC. Survey items about attitudes and beliefs were derived from the Cabana model of barriers to guideline adherence and theoretical domains framework of behavior change. RESULTS: Among 345 respondents, 324 (94%) agreed that active surveillance was appropriate for at least some patients, 81% agreed that active surveillance was at least somewhat underused, and 76% said that they would choose surgery for themselves if diagnosed with a PTC of ≤1 cm. Majority of the respondents believed that the guidelines supporting active surveillance were too vague and that the current supporting evidence was too weak. Malpractice and financial concerns were identified as additional barriers to offering active surveillance. The respondents endorsed improved information resources and evidence as possible facilitators to offering active surveillance. CONCLUSION: Although there is general support among physicians who treat low-risk PTC for the active surveillance approach, there is reluctance to offer it because of the lack of robust evidence, guidelines, and protocols.

Surgical considerations for papillary thyroid microcarcinomas.

We reevaluate current treatment recommendations of papillary thyroid microcarcinomas taking into account the indolent behavior of these tumors, and the potential morbidity that may result from an unnecessary surgery. The goals of this communication are to: 1) provide surgeons and endocrinologists with the most up-to-date evidence on management of microcarcinomas, 2) outline appropriate instances for active surveillance, and 3) describe the role of surgical interventions for microcarcinomas including lobectomy, total thyroidectomy, and central neck dissection.

The Delphian Node Revisited: An Uncommon Site of Recurrence.

The Delphian nodes (DNs) are frequently involved in cancers of the head and neck, including laryngeal and thyroid malignancies. Positivity in the DN has been considered a predictor of recurrence as well as an overall aggressive tumor biology. However, little has been written regarding the consequences of recurrence at the site of the DN. We present two case reports regarding recurrence in the DN and the unique challenges associated with DN metastases. In addition, we discuss our surgical approach to disease at the prelaryngeal space, including workup, imaging, and resection.

Undetectable Thyroglobulin Levels in Poorly Differentiated Thyroid Carcinoma Patients Free of Macroscopic Disease After Initial Treatment: Are They Useful?

BACKGROUND: Predictive role of undetectable thyroglobulin (Tg) in patients with poorly differentiated thyroid carcinoma (PDTC) is unclear. Our goal was to report on Tg levels following total thyroidectomy and adjuvant RAI in PDTC patients and to correlate Tg levels with recurrence. METHODS: Forty patients with PDTC with no distant metastases at presentation (M0) and managed by total thyroidectomy and adjuvant RAI were identified from a database of 91 PDTC patients. Of these, 31 patients had Tg values recorded and formed the basis of our analysis. A nonstimulated Tg level <1 ng/ml was used as a cutoff point for undetectable Tg levels. Association of patient and tumor characteristics with Tg levels was examined by χ (2) test. Recurrence-free survival (RFS) stratified by postop Tg level was calculated by Kaplan-Meier method and compared by log-rank test. RESULTS: Twenty patients had undetectable Tg (<1 ng/ml) and 11 had detectable Tg (≥1 ng/ml; range 2-129 ng/ml) following surgery. After adjuvant RAI, 24 patients had undetectable Tg (<1 ng/ml) and 7 had detectable Tg (≥1 ng/ml; range 1-57 ng/ml). Patients with undetectable Tg were less likely to have pathologically positive margins compared to those with detectable Tg (33 vs. 72 % respectively; p = 0.03). Patients with undetectable Tg levels had better 5-year regional control and distant control than patients with detectable Tg level (5-year regional recurrence-free survival 96 vs. 69 %; p = 0.03; 5-year distant recurrence-free survival 96 vs. 46 %, p = 0.11). CONCLUSION: Postoperative thyroglobulin levels in subset of patients with PDTC appear to have predictive value for recurrence. Patients with undetectable Tg have a low rate of recurrence.

Undetectable thyroglobulin after total thyroidectomy in patients with low- and intermediate-risk papillary thyroid cancer--is there a need for radioactive iodine therapy?

BACKGROUND: The efficacy of radioactive iodine therapy (RAI) in patients who have an undetectable thyroglobulin (Tg) level after total thyroidectomy in well-differentiated papillary thyroid cancer (PTC) is questionable. The objectives of this study were to report the risk of recurrence in patients with PTC who had an undetectable Tg level after total thyroidectomy managed with postoperative RAI and without RAI. METHODS: After approval by the institutional review board, 751 consecutive patients who had total thyroidectomy for PTC as well as postoperative Tg measurement were identified from our institutional database of 1163 patients treated for well-differentiated thyroid carcinoma at Memorial Sloan Kettering Cancer Center between 1999 and 2005. Of these, 424 patients had an undetectable postoperative Tg (defined as a Tg <1 ng/mL) of whom 80 were classified as low, 218 intermediate, and 126 high risk via use of the GAMES (grade, age, distant metastasis, extrathyroidal extension, and size of the neoplasm) criteria. Patient, neoplasm, and treatment characteristics were recorded on the low- and intermediate-risk patients. Recurrence was defined as any structural abnormality on examination or imaging and confirmed by fine-needle aspiration biopsy. Disease-specific survival and recurrence-free survival (RFS) were calculated with the Kaplan-Meier method. Univariate analysis was carried out by the log rank test and multivariate analysis by Cox proportional hazards method. RESULTS: In the low-risk group (n = 80), 35 patients received postoperative RAI and 45 did not. Comparison of patient and tumor characteristics showed patients treated without RAI were more likely to have T1 tumors (82% vs 60%, P = .027). There were no disease-specific deaths in either group. There was 1 neck recurrence in the group that did not receive RAI. Patients managed without RAI had a similar RFS to patients managed with RAI (96% vs 100%, P = .337). In the intermediate risk group (n = 218), 135 were managed with RAI and 83 without. Comparison of patient and tumor characteristics showed patients managed without RAI were more likely to be older patients (≥ 45 years: 90% vs 39%, P < .0005) with smaller tumors (pT1T2: 97% vs 62%, P < .0005) and negative neck disease (N0: 56% vs 30%, P < .0005). There were no disease specific deaths in either group. There were 7 recurrences, of which 6 were in the RAI cohort (5 regional, 1 distant) and 1 in the non-RAI cohort (1 regional). Patients managed without RAI had a similar RFS to patients managed with RAI (97% vs 96%, P = .234). CONCLUSION: Select low- and intermediate-risk group patients who have undetectable Tg after total thyroidectomy for PTC can be managed safely without adjuvant RAI with no increase in risk of recurrence.

Thyroid lobectomy for treatment of well differentiated intrathyroid malignancy.

BACKGROUND: There remains controversy over the type of surgery appropriate for T1T2N0 well differentiated thyroid cancers (WDTC). Current guidelines recommend total thyroidectomy for all but the smallest lesions, despite previous evidence from large institutions suggesting that lobectomy provides similar excellent results. The objective of this study was to report our experience of T1T2N0 WDTC managed by either thyroid lobectomy or total thyroidectomy. METHODS: Eight hundred eighty-nine patients with pT1T2 intrathyroid cancers treated surgically between 1986 and 2005 were identified from a database of 1810 patients with WDTC. Total thyroidectomy was carried out in 528 (59%) and thyroid lobectomy in 361 (41%) patients. Overall survival (OS), disease-specific survival (DSS) and recurrence-free survival (RFS) were determined by the Kaplan-Meier method. Factors predictive of outcome by univariate and multivariate analysis were determined using the log rank test and Cox proportional hazards method respectively. RESULTS: With a median follow-up of 99 months, the 10-yr OS, DSS, and RFS for all patients were 92%, 99%, and 98% respectively. Univariate analysis showed no significant difference in OS by extent of surgical resection. Multivariate analysis showed that age over 45 yr and male gender were independent predictors for poorer OS, whereas T stage and type of surgery were not. Comparison of the thyroid lobectomy group and the total thyroidectomy group showed no difference in local recurrence (0% for both) or regional recurrence (0% vs 0.8%, P = .96). CONCLUSION: Patients with pT1T2 N0 WDTC can be safely managed by thyroid lobectomy alone.

The impact of microscopic extrathyroid extension on outcome in patients with clinical T1 and T2 well-differentiated thyroid cancer.

OBJECTIVE: To report the impact of microscopic extrathyroid extension (ETE) on outcome in patients with cT1/cT2 well-differentiated thyroid cancer (WDTC), and to determine the effect of extent of surgery and adjuvant radioactive iodine (RAI) treatment on outcome in patients with microscopic ETE. PATIENTS AND METHODS: From an institutional database, we identified 984 patients (54%) who underwent surgery for cT1/T2N0 disease. Of these, 869 patients were pT1/T2 and 115 were upstaged to pT3 based on the finding of microscopic ETE. Disease-specific survival (DSS) and recurrence-free survival (RFS) were analyzed for each group using the Kaplan-Meier method. In the pT3 group, factors predictive of outcome were analyzed by univariate and multivariate analyses. RESULTS: There was no difference in the 10-year DSS (99% vs 100%; P = .733) or RFS (98% vs 95%; P = .188) on comparison of the pT1/pT2 and pT3 cohorts. Extent of surgery and administration of postoperative RAI were not significant for recurrence on univariate or multivariate analysis in the pT3 cohort. CONCLUSION: Outcomes in patients with cT1T2N0 WDTC are excellent and not affected by microscopic ETE. The extent of resection and administration of postoperative RAI in patients with microscopic ETE does not impact survival or recurrence.

Role of external beam radiotherapy in patients with advanced or recurrent nonanaplastic thyroid cancer: Memorial Sloan-kettering Cancer Center experience.

PURPOSE: External beam radiotherapy (EBRT) plays a controversial role in the management of nonanaplastic thyroid cancer. We reviewed our institution's outcomes in patients treated with EBRT for advanced or recurrent nonanaplastic thyroid cancer. METHODS AND MATERIALS: Between April 1989 and April 2006, 76 patients with nonanaplastic thyroid cancer were treated with EBRT. The median follow-up for the surviving patients was 35.3 months (range, 4.2-178.4). The lesions were primarily advanced and included Stage T2 in 5 (7%), T3 in 5 (7%), and T4 in 64 (84%) patients. Stage N1 disease was present in 60 patients (79%). Distant metastases before EBRT were identified in 27 patients (36%). The median total EBRT dose delivered was 6,300 cGy. The histologic features examined included medullary in 12 patients (16%) and nonmedullary in 64 (84%). Of the 76 patients, 71 (93%) had undergone surgery before RT, and radioactive iodine treatment was used in 56 patients (74%). RESULTS: The 2- and 4-year overall locoregional control rate for all histologic types was 86% and 72%, respectively, and the 2- and 4-year overall survival rate for all patients was 74% and 55%, respectively. No significant differences were found in locoregional control, overall survival, or distant metastases-free survival for patients with complete resection, microscopic residual disease, or gross residual disease. Grade 3 acute mucositis and dysphagia occurred in 14 (18%) and 24 (32%) patients, respectively. Late adverse toxicity was notable for percutaneous endoscopic gastrostomy tube use in 4 patients (5%). CONCLUSION: The results of our study have shown that EBRT is effective for locoregional control of selected locally advanced or recurrent nonanaplastic thyroid malignancies, with acceptable acute toxicity.

Prognostic factors of recurrence in encapsulated Hurthle cell carcinoma of the thyroid gland: a clinicopathologic study of 50 cases.

BACKGROUND: Follicular carcinomas of the thyroid gland, including its oncocytic variant (so-called Hurthle cell carcinoma), are subdivided into the indolent encapsulated ("minimally invasive") and the clinically aggressive widely invasive tumors. There are, however, cases of encapsulated follicular carcinoma that recur and metastasize. Identifying these cases at the time of diagnosis is crucial for prognostic and therapeutic considerations. Because to the authors' knowledge most studies do not focus exclusively on the encapsulated Hurthle cell carcinoma (EHC), the current study attempted to identify predictors of recurrence in EHC. METHODS: A tumor was defined as EHC if it was encapsulated, macroscopically well defined with microscopic but no macroscopic evidence of vascular or capsular invasion, and composed of > 75% follicular oncocytic cells. Retrospective chart review and microscopic examination identified 50 primary tumors meeting the above criteria at the Memorial Sloan-Kettering Cancer Center between 1967 and 2005. The cases were analyzed for various histologic and clinical parameters. Each parameter was correlated with recurrence-free survival (RFS). RESULTS: Seven of 50 (14%) patients developed disease recurrence. All patients who developed recurrence were found to have a high number of foci of vascular invasion (> or = 4). In univariate analysis, > or = 4 foci of vascular invasion (P <.0001), tumor size > 4 cm (P = .049), the presence of mitosis (P = .018), and a solid/trabecular growth pattern (P = .009) were found to be correlated with a decreased RFS. Extensive capsular invasion, gender, and age did not confer a statistically higher recurrence rate. The finding of a solid/trabecular growth and mitosis correlated with the presence of numerous foci (> or = 4) of vascular invasion (P = .01 and P = .005, respectively). CONCLUSIONS: A diligent search for vascular invasion is recommended in EHC that display mitosis or a solid/trabecular growth pattern. The presence of > or = 4 foci of vascular invasion should alert the pathologist and the clinician to a significantly higher risk of recurrence in EHC.