Vitamin D receptor and progesterone receptor protein and gene expression in papillary thyroid carcinomas: associations with histological features.

PURPOSE: Vitamin D receptor (VDR) and progesterone receptor (PR) expression has been described in papillary thyroid carcinoma (PTC) but data regarding association with tumor histological characteristics and localization of the protein expression are scarce. MATERIALS AND METHODS: Formalin-fixed, paraffin-embedded specimens from 45 patients with PTC (cases) were retrieved and tumor histological data were recorded. We analyzed gene and protein expression of VDR and PR and gene expression of vitamin D-inactivating 24-hyroxylase (CYP24A1) and the activating 1-alpha-hydroxylase (CYP27B1) enzymes in follicular cancer cells and the adjacent non-neoplastic thyroid tissue (NNTT). RESULTS: VDR mRNA and protein expression was higher in PTC compared with NNTT (p < 0.05). The protein was globally localized in the cytoplasm and cell membranes of the neoplastic cells in all cases, with differences in intensity. Cytoplasmic positivity was stronger in the majority of cases. Membranous positivity was also evident in cases, whereas in NNTT was generally weak and in a low percentage of the cells. Expression of CYP 24A1, but not CYP27B1, was increased in approximately all PTC specimens and was associated with lymph node metastasis and extrathyroidal extension. PR mRNA was increased in 34% and protein expression was present in 57% of cases, and none of NNTT. PR, but not VDR, mRNA expression was significantly associated with the tumor size (r = 0.645, p = 0.007). CONCLUSIONS: We provide evidence for the expression pattern of VDR, PR and CYP24A1 in the progression of PTC. Rapid anti-tumor responses of vitamin D in PTC may be blocked due to inactivation of local vitamin D metabolism.

Genetic screening of patients with medullary thyroid cancer in a referral center in Greece during the past two decades.

OBJECTIVE: Mutations in the RET gene are responsible for hereditary medullary thyroid cancer (MTC) and may vary between ethnic groups. We report the spectrum of mutations detected in patients with MTC in a referral center in Greece. PATIENTS AND METHODS: Screening for RET mutations was performed in 313 subjects from 188 unrelated families: 51 patients had clinical suspicion for familial disease, 133 were apparently sporadic, four patients had only C cell hyperplasia, and 125 were family members. Exons 8, 10, 11, and 13-16 were screened. RESULTS: A total of 58 individuals (30.85%) were RET mutations carriers, 120 (63.8%) were finally classified as sporadic, 13 apparently sporadic cases (9.8%) were identified with RET mutation: ten carried the exon 8 at codon 533 mutation (previously reported), two the exon 14 at codon 804 mutation, and one the exon 13 at codon 768 mutation. Six patients (3.19%) with clinical features of multiple endocrine neoplasia type 2A and negative for RET mutations were classified as 'unknown cause'. The mutations of hereditary cases were as follows: 21 cases (36.2%) in exon 8 codon 533, 19 (32.8%) in exon 11 codon 634, nine (15.5%) in exon 10, five (8.6%) in exon 16, three (5.2%) in exon 14 codon 804, and one in exon 13 codon 768 (1.7%). CONCLUSION: The spectrum of RET mutations in Greece differs from that in other populations and the prevalence of familial cases is higher. The exon 8 (Gly533Cys) mutation was the most prevalent in familial cases unlike other series, followed by exon 11 (codon 634) mutations which are the most frequent elsewhere. The wide application of genetic screening in MTC reveals new molecular defects and helps to characterize the spectrum of mutations in each ethnic group.

Obesity and thyroid cancer: epidemiologic associations and underlying mechanisms.

The incidence of thyroid cancer has been rising over the past few decades along with a parallel increase in obesity. Observational studies have provided evidence for a potential association between the two. By contrast, clinical data for a link between type 2 diabetes mellitus, a condition strongly associated with obesity, and thyroid cancer are limited and largely not supportive of such an association. Obesity leads to hypoadiponectinemia, a pro-inflammatory state, and insulin resistance, which, in turn, leads to high circulating insulin and insulin-like growth factor-1 levels, thereby possibly increasing the risk for thyroid cancer. Thus, insulin resistance possibly plays a pivotal role in underlying the observed association between obesity and thyroid cancer, potentially leading to the development and/or progression of thyroid cancer, through its interconnections with other factors including insulin-like growth factor-1, adipocytokines/cytokines and thyroid-stimulating hormone. In this review, epidemiological and clinical evidence and potential mechanisms underlying the proposed association between obesity and thyroid cancer risk are reviewed. If the association between obesity and thyroid cancer demonstrated in observational studies proves to be causal, targeting obesity (and/or downstream mediators of risk) could be of importance in the prevention and management of thyroid cancer.

The increase in thyroid cancer incidence is not only due to papillary microcarcinomas: a 40-year study in 1 778 patients.

AIM: Thyroid cancer incidence has been increased over the last decades. The aims of the present study were: (a) to identify a changing trend in thyroid cancer in Northern Greece, (b) to examine patients' and tumoral characteristics and (c) to investigate the increase of papillary microcarcinomas and that of invasive or larger cancers. PATIENTS AND METHODS: We retrospectively analyzed the records of 1 778 patients who were diagnosed with thyroid cancer between January 1971 and December 2010. The study period was divided into 4 decades: 1971-1980, 1981-1990, 1991-2000, 2001-2010. Patients were separated into 2 groups: in Group A we have included papillary thyroid microcarcinomas (PTM) and in Group B all cancers with diameter >10 mm as well as invasive cancers ≤10 mm. RESULTS: Patients diagnosed with thyroid cancer increased substantially per decade. The relative frequency of papillary thyroid cancer cases increased (from 60% up to 84.6% in the last decade) and follicular cancers decreased (from 40% down to 11.6%). During the study period, cancer size declined. Frequency of PTM (Group A) increased from 0% up to 19.3% in the last decade, but cancers of this group represent only a minority of total cancers. CONCLUSIONS: The increase of thyroid cancer in this cohort was mainly due to tumors larger than 1 cm and also to smaller in size but invasive thyroid tumors. This increase outnumbers the increase in papillary thyroid microcarcinomas.

Long-term outcome of primary endocrine non-Hodgkin lymphomas: does the site make the difference?

AIM: Primary lymphomas of endocrine glands are extremely rare. Our study adds more data to the few published series regarding the incidence, clinical characteristics, management and overall survival (OS) by comparing the various diffuse large B-cell endocrine lymphomas. Moreover, it contributes to a better understanding of these neoplasms and provides concepts for future research. METHODS: We retrospectively evaluated the clinical profile and the patterns of outcome among patients who were treated in our center with the diagnosis of aggressive, B-cell, primary endocrine lymphoma. RESULTS: Between May 1980 and December 2011, 450 patients were diagnosed as primary extranodal non-Hodgkin lymphomas. Among them, 18 cases (4%) were primary testicular lymphoma (PTL), 8 cases (2%) were primary thyroid lymphoma (PTHL) and 4 cases (1%) were primary adrenal lymphoma (PAL). The therapeutic approaches employed were variable, including mainly chemotherapy in combination with radiotherapy and surgery. The median OS for the patients with PTL and PAL was 27 and 6 months, respectively. Better outcome was observed in patients with PTHL for whom the median OS has not been reached yet, whereas the PAL group had the worst prognosis. CONCLUSIONS: The discrepancies in the outcome among endocrine lymphomas could be partly attributed to their biologic variability, which might be determined by the initial site involved. We conclude that treatment decisions should be made according to a multi-disciplinary approach to avoid unnecessary surgery. Existing treatment strategies for PTL and PAL fail to provide long-term survival, rendering the application of novel therapeutic approaches essential.

Calcitonin stimulation tests for the early diagnosis and follow-up of patients with C cell disease: a descriptive analysis.

BACKGROUND/AIM: Residual or recurrent medullary thyroid carcinoma (MTC) after thyroidectomy is diagnosed by elevated serum calcitonin (CT) levels. However, in minimal residual MTC or C-cell hyperplasia (CCH), where imaging studies are often negative, basal CT levels are frequently normal and CT stimulation tests are required. We aimed to compare CT stimulation tests with calcium, pentagastrin and their combination in identifying minimal residual MTC and CCH. MATERIAL AND METHODS: We studied 10 post-thyroidectomy patients with MTC and 20 first-degree relatives of the patients who had no clinically apparent MTC. We performed 54 combined (calcium plus pentagastrin) stimulation tests, 35 calcium stimulation tests and 26 pentagastrin stimulation tests. RESULTS: Basal CT levels were abnormal (≥500 pg/ml) in 4 patients with apparent metastatic disease (Group 1A) and in 2 patients with minimal residual disease (Group 1B) but were normal (0-300 pg/ml) in 4 patients with no residual disease (Group 1C) and in the relatives (Group 2). In Groups 1A, 1B and 1C, maximal elevation in CT levels was greater after the combined stimulation test than after calcium or pentagastrin tests. The combined stimulation test induced the greatest increases (920, 700 and 706 pg/ml, respectively) in 3 relatives (Group 2); CCH was confirmed histologically in these patients. Side-effects were mild, short-lasting and of similar intensity and duration during all tests. CONCLUSIONS: Patients with subclinical MTC (minimal residual or recurrent MTC) or their relatives (with CCH) usually have normal basal CT levels and stimulation tests are necessary. Combined test represents the most sensitive and safe stimulation test for the diagnosis of subclinical hypercalcitonemia.

Thyroid cancer in patients with hyperthyroidism.

Thyroid cancer can be associated with thyrotoxicosis caused by Graves' disease, toxic multinodular goiter, or autonomously functioning thyroid adenoma. The objective of this study was to summarize current evidence regarding the association of thyroid cancer and hyperthyroidism, particularly with respect to the type of hyperthyroidism found in some patients, and whether this affects the outcome of the patient. A PubMed search was performed up to August 2011. Articles were identified using combinations of the following keywords/phrases: thyroid cancer, papillary thyroid cancer, follicular thyroid cancer, medullary thyroid cancer, anaplastic thyroid cancer, hyperthyroidism, Graves' disease, auto-nomous adenoma, toxic thyroid nodule, and toxic multinodular goiter. Original research papers, case reports, and review articles were included. We concluded that the incidence, as well as the prognosis of thyroid cancer associated with hyperthyroidism is a matter of debate. It seems that Graves' disease is associated with larger, multifocal, and potentially more aggressive thyroid cancer than single hot nodules or multinodular toxic goiter. Patients with Graves' and thyroid nodules are at higher risk to develop thyroid cancer compared to patients with diffuse goiter. Every suspicious nodule associated with hyperthyroidism should be evaluated carefully.

Height, whole Body Surface Area, gender, working outdoors, and sunbathing in previous summer are important determinants of serum 25-hydroxyvitamin D levels.

OBJECTIVE: To investigate if serum 25-hydroxyvitamin D (25(OH)D) is related to the whole Body Surface Area (BSA), and to several other anthropometric and environmental factors. MATERIALS/METHODS: Serum 25(OH)D was determined in 489 apparently healthy subjects (346 women and 143 men, mean age 43.9 years) in April and May. From all subjects the following data were available: height, body weight, waist to hip ratio, BSA, BMI, environment of work (indoors vs. outdoors), habit of regularly sunbathing during previous summer(s), fear of sun, dwelling in city or village, and skin color. RESULTS: Approximately 43% of the participants had serum 25(OH)D levels between 10 and 20 ng/ml, 44% had values between 20.1 and 30 ng/ml, whereas about 5% had values below 10 ng/ml and only 9% had values above 30 ng/ml. There was a significant positive relationship between 25(OH)D, height and BSA, which was more pronounced for BSA in obese subjects even after adjustment for work outdoors and sunbathing during previous summer(s). Outdoor workers and sunbathers had higher 25(OH)D compared to indoor workers and non-sunbathers respectively. Men when compared to women had higher 25(OH)D regardless of BMI and this difference was apparently due to the fact that men were taller, had greater BSA, and worked more often outdoors. CONCLUSIONS: Height, whole BSA, gender, working outdoors and sunbathing in previous summer(s) proved to be significant determinants of serum 25(OH)D. Vitamin D status is higher in taller individuals with greater BSA, and in men when compared to women.

Distinct distribution of corticotropin releasing factor receptors in human breast cancer.

The hypothalamic neuropeptide corticotropin releasing factor (CRF) has been found in several types of human cancer, where its biological role is not clarified. In experimental models of breast cancer CRF has been shown to exert anti-proliferative and other actions. Aim of the present study was to describe the expression of the two types of CRF receptors CRF(1) and CRF(2) in human breast tumors. Receptor expression was studied in breast biopsies from patients diagnosed for primary breast adenocarcinoma, obtained from the tumor and the adjacent benign tissue. Gene expression levels were evaluated by real-time PCR following reverse transcription of total RNA extracts. CRF(1) transcripts were found in 23.1% of benign and in 23.1% of malignant biopsies. CRF(2(a)) was found in 22.2% of benign and 36.0% of malignant biopsies. Transcript levels of both receptors did not differ significantly between cancer and benign biopsies from the same tumor. No correlation was found between CRF receptor expression and patient histo/clinicopathological characteristics. Histological mapping using immunohistochemistry revealed positive CRF(1) immunostaining in the cancerous implants and breast ducts, whereas CRF(2) immunoreactivity was localized mainly in the perineural invasions. In conclusion, both CRF receptors were found in breast cancer and the respective benign adjacent tissue. The two CRF receptor proteins presented distinct distribution and subcellular localization, pointing into differing biological roles. CRF receptors could serve as targets of endogenous ligands expressed in the tumor microenvironment, regulating cancer growth.

Familial non-medullary thyroid carcinoma displays the features of clinical anticipation suggestive of a distinct biological entity.

Non-medullary thyroid carcinoma (NMTC) is mostly sporadic, but familial clustering is described. We aimed to compare the features of patients with sporadic and familial NMTC (FNMTC) patients and to assess whether FNMTC patients with parent-child relationship exhibit the 'anticipation' phenomenon (earlier age at disease onset and increased severity in successive generations). Among 300 NMTCs followed in the Section of Endocrinology (University of Siena, Italy), 34 (11.3%) patients, all with the papillary histotype, (16 kindred), met the criteria of FNMTC. Twenty-seven of them (79.4%) exhibited a parent-child relationship and seven (20.6%) a sibling relationship. These patients were compared with 235 patients with sporadic papillary thyroid cancer (PTCs). To analyze the features of FNMTC of the first and second generations, we cumulated the series of Siena with 32 additional FNMTC patients (15 kindred) from the Department of Endocrinology-Endocrine Oncology, Thessaloniki, Greece. Significant difference between sporadic PTC and FNMTC patients included more frequent tumor multifocality (P=0.001) and worse final outcome in FNMTC patients (P=0.001). Among 47 FNMTC with parent-child relationship, we found an earlier age at disease presentation (P<0.0001), diagnosis (P<0.0001), and disease onset (P=0.04) in the second generation when compared with the first generation. Patients in the second generation were more frequently males (P=0.02); their tumors were more frequently multifocal (P=0.003) and bilateral (P=0.01), had higher rate of lymph node metastases at surgery (P=0.02) and worse outcome (P=0.04) when compared with the first generation. In conclusion, FNMTC displays the features of clinical 'anticipation' with the second generation acquiring the disease at an earlier age and having more advanced disease at presentation.

Effects of thyroxine withdrawal in biochemical parameters and cardiac function and structure in patients with differentiated thyroid cancer.

AIM: Patients with differentiated thyroid carcinoma (DTC) are closely monitored during the first decade after diagnosis. At intervals of 1-2 years withdrawal of suppressive doses of T(4) is recommended in order to check thyroglobulin (Tg) levels under increased TSH. T(4) therapy is usually withdrawn for 5 weeks (during the first 3 weeks patients receive treatment with T(3) instead of T(4), and the last 2 weeks stop all medication). There are a few reported studies looking into the effects of T(4) withdrawal in athyreotic patients in terms of biochemical parameters and ultrasound indices. We studied patients with DTC at two time points: during suppressive T(4) treatment and at the end of the T(4) withdrawal protocol in order to identify acute changes that become apparent after 5 weeks of treatment modification. METHODS: Hormonal and biochemical parameters were measured as well as ultrasound indices of cardiac function and structure. RESULTS: Statistically significant increases were found in total cholesterol, low density lipoprotein (LDL) and high density lipoprotein (HDL) cholesterol and triglycerides with T(4) withdrawal. Creatine phosphokinase showed a striking increase with treatment withdrawal. In addition, liver enzymes, total protein and albumin concentrations increased. Creatinine levels increased significantly and sodium decreased on stopping T(4) treatment. The ultrasound indices of cardiac function and structure did not show significant changes. CONCLUSIONS: Acute hypothyroidism following T(4) withdrawal in DTC patients leads to important biochemical changes without significant alterations in cardiac function and structure. These changes may adversely affect patients, especially older patients or those with other chronic diseases.

Somatostatin receptor expression in vivo and response to somatostatin analog therapy with or without other antineoplastic treatments in advanced medullary thyroid carcinoma.

The long-term treatment of metastatic medullary thyroid carcinoma (MTC) with somatostatin (SST) analogs was evaluated in 22 patients with persistant or relapsed disease and with in vivo positive SST receptor (SSTR) tumors. After surgical intervention all patients but one, initially or at a later time, had persistenly (15) or after relapse (7) elevated serum calcitonin (CT, 252-69482 pg/ml) and carcinoembryonic antigen (CEA, 8-1130 ng/ml) concentrations; also, all of them showed positive uptake in 111In-pentetreotide scanning. Daily doses of 0.4-1.0 mg octreotide subcutaneously, or monthly doses of 20-30 mg long-acting octreotide (LAR) intramuscularly for 3-21 months were administered. Systemic chemotherapy (Ch) with or without external radiotherapy (eRT) was given to 13 patients simultaneously. A beneficial effect on pre-existing diarrhea was observed in 8 patients (subjective partial remmission, sPR 36.4%); 10 other patients showed stable disease, while in 4 a worsening of pre-existing diarrhea was observed. CT and CEA concentrations decreased more than 25% in 4 out of 22 patients (18%) and 11 patients showed a decrease of less than 25% (biological SD). No objective response in tumour growth was demonstrated. Patients (10 survivors in group B) treated with Ch+eRT plus Octerotide showed higher sR (92.5%), lower mortality (23.1%), longer mean time to death (130 months) and longer mean total survival (mts) time (145 months) in comparison to group A patients who had 66.7% sR, 33.3% mortality, only 88.5 months mean time to death and 101 months mts-time. Long-term octreotide and octreotide-LAR treatment offers a subjective and biological partial remission in one third and in one fourth of the MTC patients respectively, but it does not improve the natural course of the tumor. It remains to be answered if these drugs, combined with other antineoplastic therapies, have a synergistic effect relating to treatment response and to patient survival and mortality.