Risk Patterns of Distant Metastases in Follicular, Papillary and Medullary Thyroid Cancer.

This study of 542 patients with follicular thyroid cancer, 366 patients with the follicular variant and 1452 patients with the classical variant of papillary thyroid cancer, and 819 patients with sporadic medullary thyroid cancer operated at a tertiary referral center aimed to determine risk patterns of distant metastasis for each tumor entity, which are ill-defined. On multivariable logistic regression analyses, lymph node metastasis consistently emerged as an independent risk factor of distant metastasis, yielding odds ratios (ORs) of 2.4 and 2.8 for follicular thyroid cancer and the follicular variant of papillary thyroid cancer, and ORs of 5.9 and 6.4 for the classical variant of papillary thyroid cancer and sporadic medullary thyroid cancer. Another independent risk factor consistently associated with distant metastasis, most strongly in follicular thyroid cancer and the follicular variant of papillary thyroid cancer (OR 3.5 and 4.0), was patient age >60 years. Altogether, 2 distinct risk patterns of distant metastasis were identified, which were modulated by other cancer type-dependent risk factors: one with lymph node metastasis as leading component (classical variant of papillary thyroid cancer and sporadic medullary thyroid cancer), and another one with age as leading component (follicular thyroid cancer and the follicular variant of papillary thyroid cancer). Distant metastasis was exceptional in node-negative patients with sporadic medullary thyroid cancer (1.7%) and the classical variant of papillary thyroid cancer (1.4%), and infrequent in node-negative patients with the follicular variant of papillary thyroid cancer (4.4%). These findings delineate windows of opportunity for early surgical intervention before distant metastasis has occurred.

Thyroid cancer overdiagnosis and overtreatment: a cross- sectional study at a thyroid cancer referral center in Ecuador.

BACKGROUND: In contrast to the rapid increase in thyroid cancer incidence, the mortality has remained low and stable over the last decades. In Ecuador, however, thyroid cancer mortality has increased. The objective of this study is to determine possible drivers of high rates of thyroid cancer mortality, through a cross-sectional analysis of all patients attending a thyroid cancer referral center in Ecuador. METHODS: From June 2014 to December 2017, a cross-sectional study was conducted at the Hospital de Especialidades Eugenio Espejo, a regional reference public hospital for endocrine neoplasia in adults in Quito, Ecuador. We identified the mechanism of detection, histopathology and treatment modalities from a patient interview and review of clinical records. RESULTS: Among 452 patients, 74.8% were young adults and 94.2% (426) were female. 13.7% had a family history of thyroid cancer, and patients' median tumor size was 2 cm. The incidental finding was 54.2% whereas 45.8% was non-incidental. Thyroid cancer histology reported that 93.3% had papillary thyroid cancer (PTC), 2.7% follicular, 1.5% Hurtle cells, 1.6% medullary, 0.7% poor differentiated, and 0.2% anaplastic carcinoma. The mean MACIS (metastasis, age, completeness, invasion, and size) score was 4.95 (CI 4.15-5.95) with 76.2% of the thyroid cancer patients having MACIS score less than or equal to 6. The very low and low risk of recurrence was 18.1% (79) and 62% (271) respectively. An analysis of 319 patients with non-metastatic thyroid cancer showed that 10.7% (34) of patients had surgical complications. Moreover, around 62.5% (80 from 128 patients with thyroglobulin laboratory results) of TC patients had a stimulated-thyroglobulin value equal or higher than 2 ng/ml. Overall, a poor surgical outcome was present in 35.1% (112) patients. Out of 436 patients with differentiated thyroid carcinoma, 86% (375) received radioactive iodine. CONCLUSION: Thyroid cancer histological characteristics and method of diagnosis are like those described in other reports without any evidence of the high frequency of aggressive thyroid cancer histology. However, we observed evidence of overtreatment and poor surgical outcomes that demand additional studies to understand their association with thyroid cancer mortality in Ecuador.

Oncological outcomes in differentiated thyroid cancer in South East Scotland.

BACKGROUND: Differentiated thyroid cancer (DTC) is increasing in incidence but little is known about oncological outcomes for patients treated in the UK. Internationally there is a move toward conservative treatment of DTC. However, this is based on evidence from outside the UK. The aim of this study was to analyse oncological outcomes for a contemporary cohort of patients treated in a UK centre. METHODS: Review of 470 consecutive prospectively recorded cases of DTC from the South East of Scotland endocrine MDT 2009-2018. Data on patient, tumour and treatment details as well as recurrence and survival details were extracted from the electronic patient record. RESULTS: Of 470 patients female:male ratio was 3.4:1, median age at presentation was 48 years (range 16-86 years). Overall 193 (41%), 134 (29%), 119 (25%) and 22 (5%) patients were p T1, T2, T3, and p T4 respectively. 385 patients (82%) were pN0, 31 patients (7%) were pN1a and 53 patients (11%) were pN1b. 19 patients (4%) were M1. Of 470 patients 350 (74%) had papillary thyroid carcinoma, 120 patients (26%) had follicular carcinoma. Surgical management was lobectomy, isthumusectomy, total thyroidectomy and lobectomy then completion thyroidectomy in 14%,1%, 41% and 43% cases respectively. 64% patients received radioactive Iodine (RAI) therapy. With a median follow-up of 70 months (range 4-124 months), 5 years overall survival and disease specific survival were 96.7% and 98.5% respectively. The 5 year local recurrence free survival (LRFS), regional recurrence free survival (RRFS), locoregional recurrence free survival (LRRFS), distant recurrence free survival (DRFS) and any recurrence free survivals were 100%, 95.8%, 95.8%, 98.3% and 95% respectively. CONCLUSION: Oncological outcomes for patients treated with DTC were excellent, in keeping with experience from international groups, suggesting that a move towards conservative treatment in the UK seems reasonable.

Polyphenol intake and differentiated thyroid cancer risk in the European Prospective Investigation into Cancer and Nutrition (EPIC) cohort.

Polyphenols are bioactive compounds with several anticarcinogenic activities; however, human data regarding associations with thyroid cancer (TC) is still negligible. Our aim was to evaluate the association between intakes of total, classes and subclasses of polyphenols and risk of differentiated TC and its main subtypes, papillary and follicular, in a European population. The European Prospective Investigation into Cancer and Nutrition cohort included 476,108 men and women from 10 European countries. During a mean follow-up of 14 years, there were 748 incident differentiated TC cases, including 601 papillary and 109 follicular tumors. Polyphenol intake was estimated at baseline using validated center/country-specific dietary questionnaires and the Phenol-Explorer database. In multivariable-adjusted Cox regression models, no association between total polyphenol and the risks of overall differentiated TC (HRQ4 vs. Q1 = 0.99, 95% confidence interval [CI] 0.77-1.29), papillary (HRQ4 vs. Q1 = 1.06, 95% CI 0.80-1.41) or follicular TC (HRQ4 vs. Q1 = 1.10, 95% CI 0.55-2.22) were found. No associations were observed either for flavonoids, phenolic acids or the rest of classes and subclasses of polyphenols. After stratification by body mass index (BMI), an inverse association between the intake of polyphenols (p-trend = 0.019) and phenolic acids (p-trend = 0.007) and differentiated TC risk in subjects with BMI ≥ 25 was observed. In conclusion, our study showed no associations between dietary polyphenol intake and differentiated TC risk; although further studies are warranted to investigate the potential protective associations in overweight and obese individuals.

Randomised comparison of 1.1 GBq and 3.7 GBq radioiodine to ablate the thyroid in the treatment of low-risk thyroid cancer: a 13-year follow-up.

Purpose: The optimal activity of radioiodine (I-131) administered for ablation therapy in papillary and follicular thyroid cancer after thyroidectomy remains unknown in a long-term (> 10 year) follow-up. Some, shorter follow-up studies suggest that activities 1.1 GBq and 3.7 GBq are equally effective. We evaluated the long-term outcomes after radioiodine treatment to extend current knowledge about the optimal ablative dose of I-131.Methods: One hundred and sixty consecutive adult patients (129 females, 31 males; mean age 46 ± 14 y, range 18-89 y) diagnosed with histologically confirmed differentiated thyroid cancer, were randomised in a prospective, phase III, open-label, single-centre study, to receive either 1.1 GBq or 3.7 GBq of I-131 after thyroidectomy. At randomisation, patients were stratified according to the histologically verified cervical lymph node status and were prepared for ablation using thyroid hormone withdrawal. No uptake in the whole-body scan with I-131 and serum thyroglobulin concentration less than 1 ng/mL at 4-8 months after treatment was considered successful ablation.Results: Median follow-up time was 13.0 years (mean 11.0 ± 4.8 y; range 0.3-17.1 y). Altogether 81 patients received 1.1 GBq with successful ablation in 45 (56%) patients. In the original study, thirty-six patients (44%) needed one or more extra administrations to replete the ablation. Of these, 4 (8.9%) and 5 (14%) patients relapsed during the follow-up, respectively. Of the 79 patients treated with 3.7 GBq 45 (57%) had successful ablation after one administration of radioiodine and 34 (43%) needed several treatments. Of these, 2 (4.4%) and 9 (26.5%) patients relapsed, respectively. The groups did not differ in the proportion of patients relapsing (p = .591).Conclusion: During follow-up of median 13 years, 3.7 GBq is not superior to 1.1 GBq in the radioiodine treatment after thyroidectomy in papillary and follicular thyroid cancer.

Prevalence and diagnostic significance of noninvasive follicular thyroid neoplasm with papillary-like nuclear features among tumors previously diagnosed as follicular adenoma: a single-institutional study in Japan.

The incidence of noninvasive follicular thyroid neoplasm with papillary-like nuclear features (NIFTP) in papillary thyroid carcinoma (PTC) is significantly lower in Asian countries than Western countries; however, the difference remains unexplained. This study aimed to evaluate the incidence of NIFTP in tumors diagnosed as follicular adenoma (FA) in a Japanese institution and discuss the significance of NIFTP. In this study, 44 tumors were investigated, which were histologically diagnosed as FA at the Kuma Hospital in 2008. Of the 44 tumors, 13 (29.5%) were revised as NIFTP. In the remaining 31 tumors, the FA diagnosis was reconfirmed. On aspiration cytology, most of the NIFTPs were categorized into follicular neoplasm or suspicious for a follicular neoplasm. On histological examination, 9 (29.0%) of 31 FA nodules showed a nuclear score of 1. Twelve (92.3%) of 13 NIFTP nodules showed a nuclear score of 2, and the remaining nodule had a nuclear score of 3. No metastasis of FA or NIFTP was detected. There were no evidences of distant metastasis during follow-up. This is the first study to describe that NIFTP is more frequently included in tumors diagnosed as FA rather than PTC in Japan. As clinical management of FA and NIFTP is the same, in Japan, there is no reason to distinguish between FA and NIFTP. Conclusively, the necessity of using the disease entity "NIFTP" is not found in Japan.

Older patients with differentiated thyroid cancer exhibit more aggressive pathological characteristics than younger patients

Summary: Differentiated thyroid cancer (DTC) has long been recognized as having a worse prognosis in older people. We retrospectively evaluated the clinical and pathological characteristics of 973 sequentially treated patients with primary DTC stratified into 2 age groups, ≥ 55 or < 55 years, based on the current American Joint Committee on Cancer (AJCC) DTC staging system. We found that older patients had a higher frequency of extrathyroidal cancer extension and larger cancers, and that their cancers were less commonly completely resectable.

A Population-Based Study on NIFTP Incidence and Survival: Is NIFTP Really a "Benign" Disease?

BACKGROUND: This study aimed to determine the incidence of noninvasive follicular thyroid neoplasm with papillary-like features (NIFTP) in Ontario, Canada and the predictors of disease-free survival (DFS) by comparing patients with follicular variant papillary thyroid cancer (FVPTC) and patients with NIFTP. METHODS: This population-based retrospective cohort study included all patients who had definitive surgery for well-differentiated thyroid cancer (WDTC) in Ontario, Canada between 1990 and 2001 and were followed until 2014. A conservative decision rule was applied to subtype-select FVPTCs into NIFTPs after pathology report review. The primary outcome was DFS, for which Cox proportional hazard regression analysis was performed to assess the impact of FVPTC versus NIFTP. RESULTS: At pathology re-review of the 725 FVPTC cases, 318 were reclassified as potential NIFTP. The median follow-up time was 15.3 years for the entire cohort and 15.9 years for those alive at the last follow-up visit. Disease failure occurred for 109 patients, 79 (19.4%) in the FVPTC group and 30 (9.4%) in the NIFTP group (p < 0.01). This effect was sustained in the multivariable analysis, with FVPTC showing significantly worse DFS than NIFTP (hazard ratio, 1.84; 95% confidence interval, 1.17-2.89). After recategorization of certain FVPTCs into NIFTPs, the findings showed that NIFTP accounted for 16.8% (1.461/8.699 per 100,000) of all WDTCs. CONCLUSION: The disease failure rate for NIFTP was 9.4%. The NIFTP diagnosis is challenging for the pathologist and may make tumor behavior difficult to predict for this entity. Caution should be used in the management of patients with an NIFTP.

Risk of Recurrence in Differentiated Thyroid Cancer: A Population-Based Comparison of the 7th and 8th Editions of the American Joint Committee on Cancer Staging Systems.

BACKGROUND: Differentiated thyroid cancer (DTC) survival is excellent, making recurrence a more clinically relevant prognosticator. We hypothesized that the new American Joint Committee on Cancer (AJCC) 8th edition improves on the utility of the 7th edition in predicting the risk of recurrence in DTC. METHODS: A population-based retrospective review compared the risk of recurrence in patients with DTC according to the AJCC 7th and 8th editions using the Surveillance, Epidemiology, and End Results-based Kentucky Cancer Registry from 2004 to 2012. RESULTS: A total of 3248 patients with DTC were considered disease-free after treatment. Twenty percent of patients were downstaged from the 7th edition to the 8th edition. Most patients had stage I disease (80% in the 7th edition and 94% in the 8th edition). A total of 110 (3%) patients recurred after a median of 27 months. The risk of recurrence was significantly associated with stage for both editions (p < 0.001). In the 7th edition, there was poor differentiation between lower stages and better differentiation between higher stages (stage II hazard ratio [HR] 0.91, 95% confidence interval [CI] 0.39-2.11; stage III HR 3.72, 95% CI 2.29-6.07; stage IV HR 11.66, 95% CI 7.10-19.15; all compared with stage I). The 8th edition better differentiated lower stages (stage II HR 4.06, 95% CI 2.38-6.93; stage III HR 13.07, 95% CI 5.30-32.22; stage IV 11.88, 95% CI 3.76-37.59; all compared with stage I). CONCLUSIONS: The AJCC 8th edition better differentiates the risk of DTC recurrence for early stages of disease compared with the 7th edition. However, limitations remain, emphasizing the importance of adjunctive strategies to estimate the risk of recurrence.

Decreased staging of differentiated thyroid cancer in patients with chronic lymphocytic thyroiditis.

PURPOSE: The biological association between chronic lymphocytic thyroiditis (CLT) and differentiated thyroid cancer (DTC) has not been elucidated yet. The aim of the study was to assess whether the presence of CLT exerts any influence on clinical or histological presentation of DTC. METHODS: Nine hundred and seven consecutive patients with DTC treated in the years 1998-2016 were divided into two groups according to the presence or absence of concomitant CLT. The statistical differences were analysed. RESULTS: Out of 907 patients included in the study, 331 were diagnosed with DTC and CLT (studied group), while 576 patients with DTC but without CLT constituted a control group. The distribution of papillary and follicular thyroid cancer did not differ. In CLT group, the prevalence of pT1 was greater than for pT2-pT4 DTC (P = 0.0003; OR = 1.69, 95% CI 1.27-2.24) compared to controls (68.3 vs. 56.1%, respectively). The presence of multifocal lesions was similar. The thyroid capsule infiltration without extrathyroidal invasion (P < 0.0001; OR = 0.21, 95% CI 0.14-0.31) was more frequent in the studied group, unlike extracapsular invasion, which was significantly more often present in patients with DTC but without CLT (P = 0.004; OR = 1.66; 95% CI 1.17-2.34) as well as nodal involvement (P = 0.048; OR = 0.65, 95% CI 0.42-0.99). CONCLUSIONS: The collected data indicate a protective role of CLT in preventing the spread of the DTC. The presence of CLT might limit tumour growth to the primary site.

Thyroid disease and cancer in kidney transplantation: a single-center analysis.

BACKGROUND: Thyroid diseases are frequent in patients with end-stage renal disease, but data on renal transplant recipients are conflicting. This study evaluated the incidence of thyroid disease and cancer in a population of kidney transplant recipients performed in a single center. METHODS: Seven hundred sixty patients receiving a kidney transplantation between January 2000 and October 2017 were followed with thyroid ultrasonography to determine nodules together with thyroid hormone levels. Ultrasound-guided fine-needle aspiration citology (FNAc) was performed to the nodules > 10 mm . RESULTS: Two hundred four patients (26.8%) patients demonstrated functional or morphologic changes in the thyroid gland compared with pre-transplant period. Among the 204 patients with newly diagnosed thyroid disease, 165 patients had single or multiple nodular lesions less than 1 cm in diameter, and were followed yearly. Nodule size progression was observed in 23 patients (13.9%), and they underwent a FNAc. A total of sixty-two patients (30.3%) underwent FNAc. The biopsy samples were cytologically interpreted as benign in 20 patients (32.2%), suspicious in 40 patients (64.5%), or at high risk of cancer in 2 patients (3.2%). Forty-two patients underwent total thyroidectomy. At histological examination, 18 patients had a thyroid cancer (papillary cancer in 17 patients, follicular cancer in one). Thyroid cancer was more frequent in male patients with a mean time from transplant to diagnosis of 5.6 years. At a mean follow-up was 8 ± 1.2 years, all patients are alive with a normal functioning graft. CONCLUSIONS: Thyroid diseases are common in transplant recipients. Thyroid disease may evolve after transplantation, probably as a consequence of immunosuppression. A complete evaluation of thyroid disease is mandatory in kidney transplant recipients because early diagnosis and appropriate treatment of thyroid disease and cancer may significantly decrease the morbidity and mortality in these patients.

Occupational radiation exposure and thyroid cancer incidence in a cohort of U.S. radiologic technologists, 1983-2013.

Although childhood exposure to ionizing radiation is a well-established risk factor for thyroid cancer, the risk associated with adulthood exposure remains unclear. We prospectively examined the association between cumulative, low-to-moderate dose occupational radiation exposure to the thyroid and thyroid cancer incidence in the U.S. Radiologic Technologists cohort. The study included 89,897 members who completed at least two of four mailed questionnaires and were cancer-free at the time of the first questionnaire. Cumulative occupational thyroid radiation dose (mean = 57 mGy, range = 0-1,600 mGy) was estimated based on self-reported work histories, historical data and, during the years 1960-1997, 783,000 individual film badge measurements. During follow-up, we identified 476 thyroid cancer cases. We used Poisson regression to estimate excess relative risk of thyroid cancer per 100 milliGray (ERR/100 mGy) absorbed dose to the thyroid gland. After adjusting for attained age, sex, birth year, body mass index and pack-years smoked, we found no association between thyroid dose and thyroid cancer risk (ERR/100 mGy = -0.05, 95% CI <-0.10, 0.34). In this large cohort study of radiologic technologists, protracted, low-to-moderate dose ionizing radiation exposure to the thyroid gland in adulthood was not associated with an increased risk of thyroid cancer.

Racial/ethnic differences in thyroid cancer incidence in the United States, 2007-2014.

BACKGROUND: Small tumor diagnostic tools including ultrasound-guided fine needle aspiration (FNA) and computed tomography (CT) could be causing rising and racially/ethnically different thyroid cancer incidence rates due to variable overdiagnosis of indolent tumors. Papillary tumors and <40 mm tumors are most likely to be overdiagnosed as indolent tumors by FNA and CT. METHODS: Age-adjusted incidence rates (AAIRs) for the years 2007-2014 were calculated for race/ethnicity (white, Hispanic, Asian, African American, Native American) by patient/tumor characteristics for microscopically confirmed malignant thyroid cancer cases in the Surveillance, Epidemiology, and End Results Program 18 database (SEER 18; N = 93,607). Multivariate analysis determined cancer patients' odds ratios of diagnosis with papillary thyroid carcinoma (vs other histologies) and tumors <40 mm (vs ≥40 mm). RESULTS: For both males and females, there were statistically significant differences in incidence rates between race/ethnicity, with whites having the highest AAIRs and African Americans the lowest AAIRs. Among thyroid cancer patients, tumor size and histology differed significantly by race and insurance coverage after controlling for age, sex, stage, and tumor sequence. Non-whites with thyroid cancer (vs whites) were less associated with small tumors (odds ratio [OR], 0.51-0.79; P < .0001). Medicaid and uninsured patients with thyroid cancer were less associated with tumors <40 mm (OR, 0.55-0.71; 95% confidence interval [CI], 0.49-0.76) and papillary carcinoma (OR, 0.86; 95% CI, 0.80-0.93). CONCLUSION: The diagnosis of small tumors is occurring at greater rates in whites (vs non-whites) and insured (vs Medicaid and uninsured) patients; consequently, these groups may be vulnerable to unnecessary tests and treatments or potentially aided by early detection. Guidelines that define postdetection interventions may be needed to limit the overtreatment of indolent and small papillary carcinomas. Cancer 2018;124:1483-91. © 2018 American Cancer Society.

Incidence and histological patterns of thyroid cancer in Sri Lanka 2001-2010: an analysis of national cancer registry data.

BACKGROUND: An increasing incidence of thyroid cancer is observed in many developed countries. Increasing incidence may also reflect better reporting or increased diagnostic scrutiny. We conducted this study to examine trends in thyroid cancer incidence and histological patterns in Sri Lanka. METHODS: A retrospective cohort evaluation of patients with thyroid cancer during 2001-2010 was performed using population based data published from the Sri Lanka National Cancer Registry. Trends in incidence and histological patterns were analysed by age and gender. RESULTS: The age-standardized incidence of thyroid cancer increased from 2.44 per 100,000 in 2001 (95% confidence interval [95% CI]: 2.21-2.67) to 5.16 per 100,000 in 2010 (95% CI: 4.85-5.47); a 2.1-fold increase (p < 0.05 for trend). A greater part of this increase is attributable to increase in incidence of papillary thyroid cancer, which increased from 1.64 to 3.61 per 100,000; a 2.2-fold increase (p < 0.05 for trend). Follicular cancer showed lesser, yet a significant increase from 0.56 to 0.95 per 100,000 (p < 0.05). Other varieties of thyroid cancer showed no significant increases in incidence. Trends in the increases in incidence of papillary cancer in females showed a much greater increase compared with males (from 2.45 to 5.60 per 100,000, a 2.28-fold increase in females compared with from 0.82 to 1.55; a 1.89-fold increase in males, p < 0.001). Highest incidence of papillary cancer was observed in 30-39-year age group, which has increased from 5.56 to 12.9 per 100,000; a 2.32-fold increase (p < 0.001). CONCLUSIONS: The increasing incidence of thyroid cancer in Sri Lanka is predominantly due to the increasing incidence of papillary cancers. These trends may reflect increased detection and better reporting, although an inherent increase in the incidence is the likely main contributor. Further studies including tumour stage and mortality may help answer these questions.

Thyroid cancer: trends in incidence, mortality and clinical-pathological patterns in Zhejiang Province, Southeast China.

BACKGROUND: Thyroid cancer is the most common malignant disease of the endocrine system. Previous studies indicate a rapid increase in the incidence of thyroid cancer in recent decades, and this increase has aroused the great public concern. The aim of this study was to analyze the trends in incidence, mortality and clinical-pathological patterns of thyroid cancer in Zhejiang province. METHODS: Population-based incidence and mortality rates of thyroid cancer were collected from eight cancer registries in Zhejiang from 2000 to 2012. The incidence and mortality rates were age-standardized to Segi's world population. A Joinpoint model was used to examine secular trends in age-adjusted thyroid cancer rates with the Joinpoint Regression Program Version 4.0.0. Thyroid cancer patients were recruited from Zhejiang Cancer Hospital from 1972 to 2014. Patient demographics, tumor histology and tumor size were compared among the different periods of 1972-1985, 1986-1999 and 2000-2014. RESULTS: The age-standardized incidence rate of thyroid cancer in Zhejiang cancer registries was 2.75/105 in 2000, and increased to 19.42/105 in 2012. Additionally, we observed significantly increasing incidence rates with the Annual Percent Change (APC) of 22.86% (95%CI, 19.2%-26.7%). The age-standardized mortality of thyroid cancer in Zhejiang cancer registries was 0.23/105 in 2000 and 0.25/105 in 2012. No significant change in mortality rate was found. We observed a rapid increase in the proportions of papillary thyroid carcinoma (PTC) in 12,508 patients with thyroid carcinoma identified in the Zhejiang Cancer Hospital from 1972 to 2014 while the proportions of poorly differentiated thyroid cancer (PDTC), medullary thyroid carcinoma (MTC) and follicular thyroid carcinoma (FTC) decreased over the decades. In the PTC cases, the proportion of patients with maximum tumor diameter (MTD) < 1 cm dramatically and significantly increased from 0 in 1972-1985 to 32.1% in 2000-2014. CONCLUSIONS: A rapid increase in incidence and a stable trend in mortality of thyroid cancer were found in the distribution of thyroid cancer. Most of the increased incidence was PTC, especially the papillary thyroid microcarcinoma (PTMC) with MTD < 1 cm. This increase in incidence might be due to increased diagnosis with advanced technology.

Noninvasive follicular thyroid neoplasm with papillary-like nuclear features reclassification and its impact on thyroid malignancy rate and treatment.

BACKGROUND: The reclassification of noninvasive encapsulated follicular variant papillary thyroid carcinoma (FVPTC) to noninvasive follicular thyroid neoplasm with papillary-like nuclear features (NIFTP) may have significant implications by changing overall malignancy rates and minimizing the extent of surgical treatment. METHODS: A retrospective review of 847 patients who underwent thyroidectomy at a single institution from January 2010 to April 2016 was performed. The subgroup with FVPTC (n = 181) was re-reviewed by endocrine pathologists for reclassification to NIFTP. The overall rate of malignancy (ROM) and within each Bethesda classification was determined before and after the reclassification of NIFTP. The extent of thyroidectomy among others in patients reclassified as NIFTP was further reviewed. RESULTS: Of 847 patients who underwent thyroidectomy, there was an overall ROM of 58% (n = 495), the majority being papillary thyroid cancer (PTC) (n = 454, 92%). In 181 patients with FVPTC, 146 underwent pathology re-review. There were 32 cases (22%) reclassified as NIFTP, reducing the overall ROM to 55%. ROM decreased across Bethesda categories I to V by the following: 3% Bethesda I, 8% Bethesda II, 8% Bethesda III, 10% Bethesda IV, and 3% Bethesda V. Among NIFTP patients, 16 underwent total thyroidectomy and 16 underwent thyroid lobectomy, of which 12 had completion thyroidectomies (75%). Twenty patients (63%) underwent central neck dissection, and nine underwent postoperative radioactive iodine ablation treatment (28%). CONCLUSIONS: A significant proportion of patients with FVPTC reclassified as NIFTP may decrease the overall institutional thyroid ROM. On final pathology, NIFTP should be regarded as an indolent tumor requiring no further surgical treatment.

Differentiated thyroid cancer in children: Heterogeneity of predictive risk factors.

OBJECTIVE: To correlate clinical and pathological characteristics at diagnosis with patient long-term outcomes and to evaluate ongoing risk stratifications in a large series of paediatric differentiated thyroid cancers (DTC). STUDY DESIGN: Retrospective analysis of clinical and pathological prognostic factors of 124 paediatric patients with DTC (age at diagnosis <19 years) followed up for 10.4 ± 8.4 years. Patients with a follow-up >3 years (n = 104) were re-classified 18 months after surgery on the basis of their response to therapy (ongoing risk stratification). RESULTS: Most patients had a papillary histotype (96.0%), were older than 15 years (75.0%) and were diagnosed because of clinical local symptoms (63.7%). Persistent/recurrent disease was present in 31.5% of cases during follow-up, but at the last evaluation, only 12.9% had biochemical or structural disease. The presence of metastases in the lymph nodes of the lateral compartment (OR 3.2, 95% CI, 1.28-7.16, P = 0.01) was the only independent factor associated with recurrent/persistent disease during follow-up. At the last evaluation, biochemical/structural disease was associated with node metastases (N1a, N1b) by univariate but not multivariate analysis. Ongoing risk stratification compared to the initial risk classification method better identified patients with a lower probability of persistent/recurrent disease (NPV = 100%). CONCLUSIONS: In spite of the aggressive presentations at diagnosis, paediatric patients with DTC show an excellent response to treatment and often a favourable outcome. N1b status should be considered a strong predictor of persistent/recurrent disease which, as in adults, is better predicted by ongoing risk stratification.

Thyroid cancer after hysterectomy on benign indications: Findings from an observational cohort study in Sweden.

To investigate the association between hysterectomy and thyroid cancer subtypes based on histopathology. They did a nationwide, population-based, cohort study from 1973 to 2009 in Sweden. All women above 18 years of age during the period between January 1, 1973 and December 31, 2009 from the Register of Population (n = 5.704,202) were identified as the study population. Individual case ascertainment of primary thyroid cancer subtypes were restricted to 1993-2009 based on histological pathologic-anatomical-diagnosis from the Cancer Register. Thyroid cancer subtypes were categorized based on histological morphology as: papillary, follicular and others (including anaplastic and medullary thyroid carcinoma). Information on benign hysterectomy derived from the Swedish Inpatient Register. Women with a hysterectomy (exposed) were compared with women not having had a hysterectomy (unexposed) using Cox's proportional hazard ratios (HRs). The adjusted HR for papillary thyroid cancer was significantly increased in exposed as compared with unexposed women (HR 1.70, 95% CI 1.04-2.79). There was no significant association between hysterectomy and follicular carcinoma or other thyroid cancers. There was a clear shift in the occurrence of thyroid cancer toward a lower attained age at the time of diagnosis among the exposed but no significant difference in overall survival when comparing exposed and unexposed (HR 1.02, 95% CI 0.48-2.16) Hysterectomy was associated with an increased risk for subsequent papillary thyroid cancer and diagnosis at a younger age compared with women not having had a hysterectomy but there were no differences in survival.

Iodine deficiency a persisting problem: assessment of iodine nutrition and evaluation of thyroid nodular pathology in Portugal.

BACKGROUND: The goal of eliminating iodine deficiency (ID) by the year 2000 has still not been achieved in several countries. More than 2 billion people worldwide (over 260 million school age children) remain ID. In Europe, there are still countries, such as Portugal, without national general population data on iodine nutrition (IN). This study aims at evaluating combined complementary data of the IN of the general population through urinary iodine concentration (UIC) and the thyroid histology profile from the inland region of Beira Interior (BI), in Portugal. METHODS: UIC from a population sample of 214 volunteers (131 females and 83 males), with ages ranging from 8 to 97 years (mean 51.5 years ± SD 20.74 years), from BI was determined; the thyroid histology pattern in BI (6-year period) was evaluated; and the iodine content of the largest surface water reservoir of BI, never previously reported, was measured. RESULTS: Median UIC of 62.6 µg/L was measured. Over 92 % of the population had UIC less than 100 µg/L. From 279 histology reports evaluated, the incidence of the different types of thyroid nodular pathology in BI was established. There were 60 histologic diagnoses of malignancy. The observed ratio of papillary to follicular carcinoma relatively close to 1 and the fairly high percentage of anaplastic carcinomas are characteristic of ID areas. CONCLUSIONS: The findings of this first general population study on IN from the inland region of BI, Portugal, document significant ID. This problem, with its serious public health implications, could be corrected by having affordable iodised salt widely and generally available and by promoting a proactive population attitude generated by ample public information and educational programs as to the negative consequences of ID.

Predictive factors for recurrence of differentiated thyroid cancer in patients under 21 years of age and a meta-analysis of the current literature.

The influence of predictors for recurrence in relation to recurrence-free survival was analyzed retrospectively in differentiated thyroid cancer (DTC) patients under 21 years of age who underwent primary surgical treatment and who had a pathological diagnosis of DTC between 1983 and 2012 at Fudan University Cancer Hospital. Recurrences were retrospectively analyzed using a Cox regression model for the hazard ratio (HR) according to the clinicopathological features. A meta-analysis was performed with respect to the potential predictors for recurrence from current related studies. In the present study, there were 146 young patients aged from 7 to 20 years, with a female/male ratio of 2.65/1. Female gender was the only factor significantly associated with recurrence according to univariate (HR = 2.812, P = 0.037) and multivariate (HR = 4.107, P = 0.024) Cox regression analyses. Meta-analyses revealed that multifocality (HR = 1.91, P < 0.05) and presentation at diagnosis (HR = 1.39, P < 0.05) were highly associated with recurrence in young DTC patients. However, female gender and other factors, such as age (≤10 vs. 11-20 years), PTC (PTC vs. FTC), extrathyroidal extension, lymph node metastasis, total thyroidectomy (total vs. less than total), radioiodine therapy, and radiation history, were not associated with recurrence in young DTC patients. In conclusion, multifocality and presentation at diagnosis are strong predictive factors of recurrence in relation to recurrence-free survival. We recommend studies with larger sample sizes and longer follow-up to verify the influence of predictors for disease recurrence in young patients.