Circulating endogenous sex steroids and risk of differentiated thyroid carcinoma in men and women.

Thyroid cancer (TC) is substantially more common in women than in men, pointing to a possible role of sex steroid hormones. We investigated the association between circulating sex steroid hormones, sex hormone binding globulin (SHBG) and the risk of differentiated TC in men and women within the European Prospective Investigation into Cancer and nutrition (EPIC) cohort. During follow-up, we identified 333 first primary incident cases of differentiated TC (152 in pre/peri-menopausal women, 111 in post-menopausal women, and 70 in men) and 706 cancer-free controls. Women taking exogenous hormones at blood donation were excluded. Plasma concentrations of testosterone, androstenedione, dehydroepiandrosterone, estradiol, estrone and progesterone (in pre-menopausal women only) were performed using liquid chromatography/mass spectrometry method. SHBG concentrations were measured by immunoassay. Odds ratios (ORs) were estimated using conditional logistic regression models adjusted for possible confounders. No significant associations were observed in men and postmenopausal women, while a borderline significant increase in differentiated TC risk was observed with increasing testosterone (adjusted OR T3 vs T1: 1.68, 95% CI: 0.96-2.92, ptrend = .06) and androstenedione concentrations in pre/perimenopausal women (adjusted OR T3 vs T1: 1.78, 95% CI: 0.96-3.30, ptrend = .06, respectively). A borderline decrease in risk was observed for the highest progesterone/estradiol ratio (adjusted OR T3 vs T1: 0.54, 95% CI: 0.28-1.05, ptrend = .07). Overall, our results do not support a major role of circulating sex steroids in the etiology of differentiated TC in post-menopausal women and men but may suggest an involvement of altered sex steroid production in pre-menopausal women.

The correlation between small papillary thyroid cancers and gamma radionuclides Cs-137, Th-232, U-238 and K-40 using spatially-explicit, register-based methods.

A steep increase of small papillary thyroid cancers (sPTCs) has been observed globally. A major risk factor for developing PTC is ionizing radiation. The aim of this study is to investigate the spatial distribution of sPTC in Sweden and the extent to which prevalence is correlated to gamma radiation levels (Caesium-137 (Cs-137), Thorium-232 (Th-232), Uranium-238 (U-238) and Potassium-40 (K-40)) using multiple geospatial and geostatistical methods. The prevalence of metastatic sPTC was associated with significantly higher levels of Gamma radiation from Th-232, U-238 and K-40. The association is, however, inconsistent and the prevalence is higher in densely populated areas. The results clearly indicate that sPTC has causative factors that are neither evenly distributed among the population, nor geographically, calling for further studies with bigger cohorts. Environmental factors are believed to play a major role in the pathogenesis of the disease.

Risk factors for recurrent disease in small papillary thyroid cancers - a Swedish register-based study.

AIMS: To study the correlation between clinicopathological risk factors and the risk for intervention-requiring cancer recurrence in patients with small papillary thyroid cancers (sPTCs). MATERIALS AND METHODS: Records for 397 patients with sPTC (T1 ≤ 20mm) were obtained from the Scandinavian Quality Register for Thyroid, Parathyroid and Adrenal Surgery (SQRTPA) between 2010 and 2016. Follow-up time was at least 5 years. Data regarding intervention-requiring cancer recurrence were obtained from patient medical records and analysed regarding lymph node (LN) status (N0, N1a and N1b) and recurrence. RESULTS: Age was significantly lower in the N1a and N1b groups compared to N0 (45 vs. 40.5 vs. 49 years, respectively; p = 0.002). Tumour size was smaller in the N1a group compared to N1b group (9 vs. 11.8 mm; p <0.01). The mean number of metastatic LNs at initial surgery was higher in the N1b compared to N1a group (6.6 vs. 3; p = 0.001), and in the recurrent compared to the non-recurrent group (7 versus 3.9; p <0.01). The recurrence rate was higher in the N1b group than the N1a and N0 groups (25% vs. 2.4% vs. 1.4%, respectively; p = 0.001). CONCLUSIONS: Lymph node stage N1b at diagnosis, and having five or more metastatic nodes, are strong risk factors for cancer recurrence and decreased disease-free survival in sPTC. The management of patients with sPTC should include thorough lymph node mapping for optimal treatment and individual risk stratification.

The expression of stromal biomarkers in small papillary thyroid carcinomas.

BACKGROUND: The importance of stroma for tumor progression is recognized for many cancer types. In this study, we aim to evaluate the expression of types I (Col1) and IV (Col4) collagens, alpha-smooth muscle actin (a-SMA), and matrix metallopeptidase 9 (MMP-9) in the tumor stroma of small papillary thyroid carcinoma (PTC). MATERIAL AND METHODS: Twenty-five non-metastatic small PTCs (pT1N0) and nineteen metastatic small PTCs (pT1N1b) including corresponding metastatic lateral lymph nodes were selected and paraffinized tissue blocks retrieved. The samples were stained for Col1, COL4, a-SMA, and MMP-9 antibodies using immunohistochemistry. The expression of the stromal proteins was scored and analyzed based on the location, intensity, and distribution. RESULTS: Col1 and Col4 expression were significantly higher in normal thyroid tissue compared to PTC tissue. On the contrary, expression of a-SMA and MMP-9 was higher in PTC tissue compared to normal thyroid tissue. Both Col1 and Col4 were significantly more highly expressed in the non-metastatic tumors compared with metastatic tumors. The expression of a-SMA and MMP9 was slightly, but not significantly, higher in the metastasized tumors and their respective lymph nodes. There was a significant correlation between the metastasized tumors and their respective lymph nodes in Col1 and MMP-9 expression. CONCLUSIONS: Col1, Col4, a-SMA, and MMP-9 expression in PTCs differs significantly from that of normal thyroid tissue. The higher expression of Col1 and Col4 in normal thyroid tissue and in the non-metastasized tumors indicates that Col1 and 4 might have a potential protective role in tumor progression. The higher expression of a-SMA and MMP9 in PTCs indicates that these proteins might have a role in promoting PTC progression and aggressiveness.

Adherence to mediterranean diet and the risk of differentiated thyroid cancer in a European cohort: The EPIC study.

Background: The Mediterranean diet (MD) has been proposed as a healthy diet with a potential to lower the incidence of several types of cancer, but there is no data regarding thyroid cancer (TC). We investigated the association between MD adherence, and its components, and the differentiated TC risk within the European Prospective Investigation into Cancer and Nutrition (EPIC) cohort. Methods: Over 450,000 men and women from nine European countries were followed up for a mean of 14.1 years, during which 712 differentiated TC cases were identified. Adherence to MD was estimated using the relative MD (rMED) score, an 18-point scale including alcohol, and the adapted rMED (arMED) score, a 16-point scale excluding alcohol. Hazard ratios (HRs) and 95% confidence intervals (CIs) were estimated using Cox regression models adjusted for potential confounding factors. Results: Adherence to the arMED score was not associated with the risk of differentiated TC (HRhigh vs. low adherence = 0.94, 95% CI: 0.70-1.25; p-trend 0.27), while a suggestive, but non-statistically significant inverse relationship was observed with rMED (HRhigh vs. low adherence = 0.88, 95% CI: 0.68-1.14; p-trend 0.17). Low meat (HRlow vs. high meat intake = 0.81, 95% CI: 0.67-0.99; p-trend = 0.04) and moderate alcohol (HRmoderate vs. non-moderate intake = 0.88, 95% CI: 0.75-1.03) intake were related with lower differentiated TC risk. Conclusions: Our study shows that a high adherence to MD is not strongly related to differentiated TC risk, although further research is required to confirm the impact of MD and, especially, meat intake in TC risk.

Learning by doing: an observational study of the learning curve for ultrasonic fundus-first dissection in elective cholecystectomy.

BACKGROUND: Surgical safety and patient-related outcomes are important considerations when introducing new surgical techniques. Studies about the learning curves for different surgical procedures are sparse. The aim of this observational study was to evaluate the learning curve for ultrasonic fundus-first (FF) dissection in elective laparoscopic cholecystectomy (LC). METHODS: The study was conducted at eight hospitals in Sweden between 2017 and 2019. The primary endpoint was dissection time, with secondary endpoints being intra- and postoperative complication rates and the surgeon's self-assessed performance level. Participating surgeons (n = 16) were residents or specialists who performed LC individually but who had no previous experience in ultrasonic FF dissection. Each surgeon performed fifteen procedures. Video recordings from five of the procedures were analysed by two external surgeons. Patient characteristics and data on complications were retrieved from the Swedish Registry of Gallstone Surgery and Endoscopic Retrograde Cholangiopancreatography (GallRiks). RESULTS: Dissection time decreased as experience increased (p = 0.001). Surgeons with limited experience showed more rapid progress. The overall complication rate was 14 (5.8%), including 3 (1.3%) potentially technique-related complications. Video assessment scores showed no correlation with the number of procedures performed. The self-assessed performance level was rated lower when the operation was more complicated (p < 0.001). CONCLUSIONS: Our results show that dissection time decreased with increasing experience. Most surgeons identified both favourable and unfavourable aspects of the ultrasonic FF technique. The ultrasonic device is considered well suited for gallbladder surgery, but most participating surgeons preferred to dissect the gallbladder the traditional way, beginning in the triangle of Calot. Nevertheless, LC with ultrasonic FF dissection can be considered easy to learn with a low complication rate during the initial learning curve, for both residents and specialists.

Blood polyphenol concentrations and differentiated thyroid carcinoma in women from the European Prospective Investigation into Cancer and Nutrition (EPIC) study.

BACKGROUND: Polyphenols are natural compounds with anticarcinogenic properties in cellular and animal models, but epidemiological evidence determining the associations of these compounds with thyroid cancer (TC) is lacking. OBJECTIVES: The aim of this study was to evaluate the relations between blood concentrations of 36 polyphenols and TC risk in EPIC (the European Prospective Investigation into Cancer and Nutrition). METHODS: A nested case-control study was conducted on 273 female cases (210 papillary, 45 follicular, and 18 not otherwise specified TC tumors) and 512 strictly matched controls. Blood polyphenol concentrations were analyzed by HPLC coupled to tandem MS after enzymatic hydrolysis. RESULTS: Using multivariable-adjusted conditional logistic regression models, caffeic acid (ORlog2: 0.55; 95% CI: 0.33, 0.93) and its dehydrogenated metabolite, 3,4-dihydroxyphenylpropionic acid (ORlog2: 0.84; 95% CI: 0.71, 0.99), were inversely associated with differentiated TC risk. Similar results were observed for papillary TC, but not for follicular TC. Ferulic acid was also inversely associated only with papillary TC (ORlog2: 0.68; 95% CI: 0.51, 0.91). However, none of these relations was significant after Bonferroni correction for multiple testing. No association was observed for any of the remaining polyphenols with total differentiated, papillary, or follicular TC. CONCLUSIONS: Blood polyphenol concentrations were mostly not associated with differentiated TC risk in women, although our study raises the possibility that high blood concentrations of caffeic, 3,4-dihydroxyphenylpropionic, and ferulic acids may be related to a lower papillary TC risk.

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.

The Impact of a Surgical Unit's Structure and Operative Technique on Quality in Two Swedish Rural Hospitals.

Introduction: Laparoscopic cholecystectomy (LC) is a commonly performed surgical procedure with a low complication rate. It is performed either as an acute or as an elective procedure. Most elective LCs are performed on nonlethal diseases and this is why good quality is important. Our study compared the quality of LC in two surgical units in northern Sweden (Sundsvall and Östersund) which use different clinical structures (subspecialised vs. general surgery) and surgical techniques (ultrasound fundus first vs. conventional diathermy). The study aimed to investigate whether these differences affected the quality of outcomes after LC. Materials and methods: This is a registry-based study which included 607 elective LCs from January 2014 to May 2016. There were 286 from Sundsvall and 321 from Östersund. Primary outcomes were operative time and the percentage of day surgeries. The secondary outcome was the presence of postoperative complications within the first 30 days in terms of bile duct injury, bleeding that necessitated reoperation, bile leakage and abscesses treated with drainage and mortality. Results: The time length of surgery was shorter in Sundsvall (mean 48.3 min) compared to Östersund (mean 108.6 min, p < 0.001. The percentage of day care surgeries was 94% in Sundsvall and 23% in Östersund, p < 0.001. Six patients (2.1%) had a complication in Sundsvall compared to seven patients (2.2%) in Östersund, p = 1.00. Conclusion: There is a significant difference between the two hospitals regarding operative time and the percentage of day surgeries. Complication rates in both units were equal and low.

Invasiveness and Metastatic Aggressiveness in Small Differentiated Thyroid Cancers: Demography of Small Papillary Thyroid Carcinomas in the Swedish Population.

BACKGROUND: The western world is seeing a rising incidence of thyroid cancer. Improved diagnostic methods do not entirely explain this increase. Papillary thyroid carcinoma (PTC) is the most common subtype of thyroid cancer. Small PTC (≤20 mm) and especially papillary thyroid microcarcinomas (PTMC ≤10 mm) are considered to be low-risk tumors but some cases are considerably more aggressive. Sufficient understanding of these mechanisms is a long-term goal for more efficient and safer treatment of these tumors. METHODS: We identified 959 cases of small PTCs in the validated Scandinavian Quality Register for Thyroid, Parathyroid and Adrenal Surgery, grouped according to lymph node metastasis. These were analyzed according to age, gender, tumor size and geographic region. RESULTS: Patients with N1b disease (lateral lymph nodes metastases) had a smaller tumor size compared to patients with N1a disease (8.6 mm vs 10.1 mm respectively, p < 0.05). Patients and specifically females with N1b disease were younger than those with N0 or N1a disease. Patients with N1b disease had a lower proportion of females (60%) compared to N0 and N1a groups (81% and 78%, respectively). The incidence of operated small PTCs and of lymph node engagement differs between geographic regions in Sweden. CONCLUSIONS: Small PTC and especially PTMC seem to show different patterns of aggressiveness and demography regarding lateral lymph node metastases and 7% had N1b disease and tumor <1 cm, underscoring the importance of lymph node evaluation in PTMC patients. More understanding of predictive factors, mechanisms for metastatic disease and causes of regional differences, is needed.

Outcomes After Surgery for Unilateral Dominant Primary Aldosteronism in Sweden.

BACKGROUND: Primary aldosteronism (PA) is the most common cause of secondary hypertension. Surgery is the mainstay of treatment for unilateral dominant PA, but reported cure rates varies. The aim of the present study was to investigate contemporary follow-up practices and cure rates after surgery for PA in Sweden. METHODS: Patients operated for PA and registered in the Scandinavian Quality Register for Thyroid, Parathyroid and Adrenal Surgery (SQRTPA) 2009-2015 were identified. Patient data were extracted, and follow-up data (1-24 months) was recorded. Doses of antihypertensive medication and potassium supplementation were calculated using defined daily doses (DDD), and the Primary Aldosteronism Surgical Outcome (PASO) criteria were used to evaluate outcomes. RESULTS: Of 190 registered patients, 171 (47% female, mean age 53 years, median follow-up 3.7 months) were available for analysis. In 75 patients (44%), missing data precluded evaluation of biochemical cure according to the PASO criteria. Minimal invasive approach was used in 168/171 patients (98%). Complication rate (Clavien-Dindo >3a) was 3%. No mortality was registered. Pre/postoperatively 98/66% used antihypertensives (mean DDD 3.7/1.5). 89/2% had potassium supplementation (mean DDD 2.0/0) before/after surgery. Complete/partial biochemical and clinical success according to the PASO criteria were achieved in 92/7% and 34/60%, respectively. CONCLUSION: In this study, reflecting contemporary clinical practice in Sweden complete/partial biochemical and clinical success after surgery for PA was 92/7% and 34/60%. Evaluation of biochemical cure was hampered by lack of uniform reporting of relevant outcome measures. We suggest mandatory reporting of surgical outcomes using the PASO criteria for all units performing surgery for PA.

Coffee and tea drinking in relation to the risk of differentiated thyroid carcinoma: results from the European Prospective Investigation into Cancer and Nutrition (EPIC) study.

PURPOSE: Coffee and tea constituents have shown several anti-carcinogenic activities in cellular and animal studies, including against thyroid cancer (TC). However, epidemiological evidence is still limited and inconsistent. Therefore, we aimed to investigate this association in a large prospective study. METHODS: The study was conducted in the EPIC (European Prospective Investigation into Cancer and Nutrition) cohort, which included 476,108 adult men and women. Coffee and tea intakes were assessed through validated country-specific dietary questionnaires. RESULTS: During a mean follow-up of 14 years, 748 first incident differentiated TC cases (including 601 papillary and 109 follicular TC) were identified. Coffee consumption (per 100 mL/day) was not associated either with total differentiated TC risk (HRcalibrated 1.00, 95% CI 0.97-1.04) or with the risk of TC subtypes. Tea consumption (per 100 mL/day) was not associated with the risk of total differentiated TC (HRcalibrated 0.98, 95% CI 0.95-1.02) and papillary tumor (HRcalibrated 0.99, 95% CI 0.95-1.03), whereas an inverse association was found with follicular tumor risk (HRcalibrated 0.90, 95% CI 0.81-0.99), but this association was based on a sub-analysis with a small number of cancer cases. CONCLUSIONS: In this large prospective study, coffee and tea consumptions were not associated with TC risk.

Primary Hyperparathyroidism is Underdiagnosed and Suboptimally Treated in the Clinical Setting.

PURPOSE: To evaluate whether patients presenting with laboratory results consistent with primary hyperparathyroidism (pHPT) are managed in accordance with guidelines. METHODS: The laboratory database at a hospital in Sweden, serving 127,000 inhabitants, was searched for patients with biochemically determined pHPT. During 2014, a total of 365 patients with biochemical laboratory tests consistent with pHPT were identified. Patients with possible differential diagnoses or other reasons for not being investigated according to international guidelines were excluded after scrutinizing records, after new blood tests, and clinical assessments by endocrine surgeons. RESULTS: Altogether, 92 patients had been referred to specialists and 82 had not. The latter group had lower serum calcium (median 2.54 mmol/L) and PTH (5.7 pmol/L). Out of these 82 cases, 9 patients were diagnosed with pHPT or had some sort of long-term follow-up planned as outpatients. CONCLUSION: Primary hyperparathyroidism is overlooked and underdiagnosed in a number of patients in the clinical setting. It is important to provide local guidelines for the management of patients presenting with mild pHPT to ensure that these patients receive proper evaluation and follow-up according to current research.

Consumption of fruits, vegetables and fruit juices and differentiated thyroid carcinoma risk in the European Prospective Investigation into Cancer and Nutrition (EPIC) study.

Fruit and vegetable (F&V) intake is considered as probably protective against overall cancer risk, but results in previous studies are not consistent for thyroid cancer (TC). The purpose of this study is to examine the association between the consumption of fruits, vegetables, fruit juices and differentiated thyroid cancer risk within the European Prospective Investigation into Cancer and Nutrition (EPIC) study. The EPIC study is a cohort including over half a million participants, recruited between 1991 and 2000. During a mean follow-up of 14 years, 748 incident first primary differentiated TC cases were identified. F&V and fruit juice intakes were assessed through validated country-specific dietary questionnaires. Hazard ratios (HRs) and 95% confidence intervals (CIs) were estimated using Cox regression models adjusted for potential confounding factors. Comparing the highest versus lowest quartile of intake, differentiated TC risk was not associated with intakes of total F&V (HR: 0.89; 95% CI: 0.68-1.15; p-trend = 0.44), vegetables (HR: 0.89; 95% CI: 0.69-1.14; p-trend = 0.56), or fruit (HR: 1.00; 95% CI: 0.79-1.26; p-trend = 0.64). No significant association was observed with any individual type of vegetable or fruit. However, there was a positive borderline trend with fruit juice intake (HR: 1.23; 95% CI: 0.98-1.53; p-trend = 0.06). This study did not find any significant association between F&V intakes and differentiated TC risk; however a positive trend with fruit juice intake was observed, possibly related to its high sugar content.

Consumption of Fish Is Not Associated with Risk of Differentiated Thyroid Carcinoma in the European Prospective Investigation into Cancer and Nutrition (EPIC) Study.

Background: Differentiated thyroid cancer (TC) is the most common endocrine cancer. Fish can be an important source of iodine and other micronutrients and contaminants that may affect the thyroid gland and TC risk.Objective: We prospectively evaluated the relations between the consumption of total fish and different fish types and shellfish and TC risk in the EPIC (European Prospective Investigation into Cancer and Nutrition) study.Methods: EPIC is a cohort of >500,000 men and women, mostly aged 35-70 y, who were recruited in 10 European countries. After a mean follow-up of 14 y, 748 primary differentiated TC cases were diagnosed; 666 were in women and 601 were papillary TC. Data on intakes of lean fish, fatty fish, fish products, and shellfish were collected by using country-specific validated dietary questionnaires at recruitment. Multivariable Cox regression was used to calculate HRs and 95% CIs adjusted for many potential confounders, including dietary and nondietary factors.Results: No significant association was observed between total fish consumption and differentiated TC risk for the highest compared with the lowest quartile (HR: 1.03; 95% CI: 0.81, 1.32; P-trend = 0.67). Likewise, no significant association was observed with the intake of any specific type of fish, fish product, or shellfish. No significant heterogeneity was found by TC subtype (papillary or follicular tumors), by sex, or between countries with low and high TC incidence.Conclusion: This large study shows that the intake of fish and shellfish was not associated with differentiated TC risk in Europe, a region in which iodine deficiency or excess is rare.

Energy and macronutrient intake and risk of differentiated thyroid carcinoma in the European Prospective Investigation into Cancer and Nutrition study.

Incidence rates of differentiated thyroid carcinoma (TC) have increased in many countries. Adiposity and dietary risk factors may play a role, but little is known on the influence of energy intake and macronutrient composition. The aim of this study was to investigate the associations between TC and the intake of energy, macronutrients, glycemic index (GI) and glycemic load in the European Prospective Investigation into Cancer and Nutrition (EPIC) cohort. The study included 477,274 middle-age participants (70.2% women) from ten European countries. Dietary data were collected using country-specific validated dietary questionnaires. Total carbohydrates, proteins, fats, saturated, monounsaturated and polyunsaturated fats (PUFA), starch, sugar, and fiber were computed as g/1,000 kcal. Multivariable Cox regression was used to calculate multivariable adjusted hazard ratios (HR) and 95% confidence interval (CI) by intake quartile (Q). After a mean follow-up time of 11 years, differentiated TC was diagnosed in 556 participants (90% women). Overall, we found significant associations only with total energy (HRQ4 vs .Q1 , 1.29; 95% CI, 1.00-1.68) and PUFA intakes (HRQ4 vs .Q1 , 0.74; 95% CI, 0.57-0.95). However, the associations with starch and sugar intake and GI were significantly heterogeneous across body mass index (BMI) groups, i.e., positive associations with starch and GI were found in participants with a BMI ≥ 25 and with sugar intake in those with BMI < 25. Moreover, inverse associations with starch and GI were observed in subjects with BMI < 25. In conclusion, our results suggest that high total energy and low PUFA intakes may increase the risk of differentiated TC. Positive associations with starch intake and GI in participants with BMI ≥ 25 suggest that those persons may have a greater insulin response to high starch intake and GI than lean people.

Baseline and lifetime alcohol consumption and risk of differentiated thyroid carcinoma in the EPIC study.

BACKGROUND: Results from several cohort and case-control studies suggest a protective association between current alcohol intake and risk of thyroid carcinoma, but the epidemiological evidence is not completely consistent and several questions remain unanswered. METHODS: The association between alcohol consumption at recruitment and over the lifetime and risk of differentiated thyroid carcinoma was examined in the European Prospective Investigation into Cancer and Nutrition. Among 477 263 eligible participants (70% women), 556 (90% women) were diagnosed with differentiated thyroid carcinoma over a mean follow-up of 11 years. Hazard ratios (HRs) and 95% confidence intervals (CIs) were estimated using multivariable Cox proportional hazards models. RESULTS: Compared with participants consuming 0.1-4.9 g of alcohol per day at recruitment, participants consuming 15 or more grams (approximately 1-1.5 drinks) had a 23% lower risk of differentiated thyroid carcinoma (HR=0.77; 95% CI=0.60-0.98). These findings did not differ greatly when analyses were conducted for lifetime alcohol consumption, although the risk estimates were attenuated and not statistically significant anymore. Similar results were observed by type of alcoholic beverage, by differentiated thyroid carcinoma histology or according to age, sex, smoking status, body mass index and diabetes. CONCLUSIONS: Our study provides some support to the hypothesis that moderate alcohol consumption may be associated with a lower risk of papillary and follicular thyroid carcinomas.

Reproductive and menstrual factors and risk of differentiated thyroid carcinoma: the EPIC study.

Differentiated thyroid carcinoma (TC) is threefold more common in women than in men and, therefore, a role of female hormones in the etiology of differentiated TC has been suggested. We assessed these hypotheses in the European Prospective Investigation into Cancer and Nutrition (EPIC) cohort. Among 345,157 women (mean age 51) followed for an average of 11 years, 508 differentiated TC cases were identified. Hazard ratios (HRs) and 95% confidence intervals (CIs) were estimated using Cox proportional hazards regression models. No significant associations were observed between differentiated TC risk and number of pregnancies, breast feeding, menopausal status, and age at menarche and at menopause. Significant associations were found with history of infertility problems (HR 1.70; 95% CI 1.12-2.60), a recent pregnancy (HR for ≤ 5 vs. >5 years before recruitment 3.87; 95% CI 1.43-10.46), menopause type (HR for surgical vs. natural menopause: 2.16; 95% CI 1.41-3.31), oral contraceptive (OC) use at recruitment (HR: 0.48; 95% CI 0.25-0.92) and duration of OC use (HR for ≥ 9 vs. ≤ 1 year: 0.66; 95% CI: 0.50-0.89). An increased risk was also found with hormone replacement therapy use at recruitment (HR = 1.30, 95% CI 1.02-1.67), but this was not significant after adjustment for type of menopause (HR = 1.22, 95% CI 0.95-1.57). Overall, our findings do not support a strong role of reproductive and menstrual factors, and female hormone use in the etiology of differentiated TC. The few observed associations may be real or accounted for by increased surveillance in women who had infertility problems, recent pregnancies or underwent surgical menopause.

Thyroid-stimulating hormone, thyroglobulin, and thyroid hormones and risk of differentiated thyroid carcinoma: the EPIC study.

BACKGROUND: Increased levels of thyroglobulin (Tg) and thyroid-stimulating hormone (TSH) are associated with differentiated thyroid carcinoma (TC) risk, but strong epidemiological evidence is lacking. METHODS: Three hundred fifty-seven incident TC case patients (n = 300 women and 57 men; mean age at blood collection = 51.5 years) were identified in the EPIC cohort study and matched with 2 (women) or 3 (men) control subjects using incidence density sampling. Matching included study center, sex, age, date, time, and fasting status at blood collection. Levels of total and free (f) thyroxine (T4) and triiodo-thyronine (T3), TSH, Tg, and anti-Tg antibodies (TgAb) were measured by commercially available immunoassays. Odds ratios (ORs) and 95% confidence intervals (CIs) were computed using conditional logistic regression. All statistical tests were two-sided. RESULTS: TC risk was positively associated with Tg (OR for the highest vs lowest quartile = 9.15; 95% CI = 5.28 to 15.90; P < .001) and negatively associated with TSH level (OR = 0.56; 95% CI = 0.38 to 0.81; P = .001). Odds ratios were not modified by adjustment for weight and height and were consistent across sexes, age groups, and countries. The association with Tg was stronger in follicular than papillary TC. The odds ratio for TgAb-positivity was 1.50 (95% CI = 1.05 to 2.15; P = .03). Among case patients, TSH level was stable over time, whereas Tg level was higher in proximity to TC diagnosis. Areas under the receiver operating characteristic curve were 57% and 74% for TSH and Tg level, respectively. CONCLUSIONS: High Tg levels precede by up to 8 years the detection of TC, pointing to a long sojourn time of the disease. Low TSH levels may predispose to TC onset. Neither marker has sufficient accuracy to be a screening test.

Insulin-like growth factor-i and risk of differentiated thyroid carcinoma in the European prospective investigation into cancer and nutrition.

BACKGROUND: Little is known about the causes of thyroid cancer, but insulin-like growth factor-I (IGF-I) might play an important role in its development due to its mitogenic and antiapoptotic properties. METHODS: This study prospectively investigated the association between serum IGF-I concentrations and risk of differentiated thyroid carcinoma in a case-control study nested within the European Prospective Investigation into Cancer and Nutrition. The 345 incident cases of differentiated thyroid carcinoma were individually matched to 735 controls by study center, sex and age, date, time, and fasting status at blood collection, follow-up duration, and for women menopausal status, use of exogenous hormones, and phase of menstrual cycle at blood collection. Serum IGF-I concentrations were measured by immunoassay, and risk of differentiated thyroid cancer in relation to IGF-I concentration was estimated using conditional logistic regression. RESULTS: There was a positive association between IGF-I concentrations and risk of differentiated thyroid carcinoma: the OR for a doubling in IGF-I concentration was 1.48 (95% confidence interval, 1.06-2.08; Ptrend = 0.02). The positive association with IGF-I was stable over time between blood collection and cancer diagnosis. CONCLUSION: These findings suggest that IGF-I concentrations may be positively associated with risk of differentiated thyroid carcinoma. IMPACT: This study provides the first prospective evidence of a potential association between circulating IGF-I concentrations and risk of differentiated thyroid carcinoma and may prompt the further investigations needed to confirm the association.