Mönckeberg sclerosis in patients with thyroid papillary carcinoma.

Background: Mönckeberg sclerosis is a form of calcification of the tunica media of small and medium size arteries. It occurs more often in the peripheral arteries of the lower limbs and it has been associated with diabetes and renal disease. Although there are a few reports of Mönckeberg sclerosis in thyroid vessels, there are no data regarding its significance in thyroid disease. Objective: The aim was to investigate the possible prognostic value of Mönckeberg sclerosis in thyroid vessels of patients with diagnosed thyroid cancer. Methods: We retrospectively studied patients with papillary thyroid cancer treated at the Theagenio Hospital of Thessaloniki from 2005 to 2021. The patients were divided into two groups based on the presence, or absence, of histopathological findings of Mönckeberg sclerosis in the thyroid vessels along with papillary thyroid cancer. Patient characteristics, histopathological details, personal history of thyroid disease, and metabolic parameters were compared between the two groups. Results: Thirty-three patients with papillary thyroid carcinoma and Mönckeberg sclerosis were identified and matched to 33 controls with papillary thyroid cancer, without evidence of Mönckeberg sclerosis. The metabolic profile of patients with Mönckeberg sclerosis was not significantly different from those who did not have Mönckeberg sclerosis. Moreover, the comparison between the two groups did not reveal any remarkable differences in terms of the aggressiveness of the disease. Conclusion: The presence of Mönckeberg sclerosis does not seem to impact on histological characteristics of patients with papillary thyroid cancer.

Diagnostic Accuracy of Ultrasound and Fine-Needle Aspiration Cytology in Thyroid Malignancy.

Introduction: Thyroid nodule incidence is increasing due to the widespread application of ultrasonography. Fine-needle aspiration cytology is widely applied for the detection of malignancies. The aim of this study was to evaluate the predictive value of ultrasonography in thyroid cancer. Methods: This retrospective study included patients that underwent total thyroidectomy for benign thyroid disease or well-differentiated thyroid carcinoma from January 2017 to December 2022. The study population was divided into groups: the well-differentiated thyroid cancer group and the control group with benign histopathological reports. Results: In total, 192 patients were enrolled in our study; 159 patients were included in the well-differentiated thyroid cancer group and 33 patients in the control group. Statistical analysis demonstrated that ultrasonographic findings such as microcalcifications (90.4%), hypoechogenicity (89.3%), irregular margins (92.2%) and taller-than-wide shape (90.5%) were correlated to malignancy (p < 0.001). Uni- and multivariate analysis revealed that both US score (OR: 2.177; p < 0.001) and Bethesda System (OR: 1.875; p = 0.002) could predict malignancies. In terms of diagnostic accuracy, the US score displayed higher sensitivity (64.2% vs. 33.3%) and better negative predictive value (34.5% vs. 24.4%) than the Bethesda score, while both scoring systems displayed comparable specificities (90.9% vs. 100%) and positive predictive values (97.1% vs. 100%). Discussion: The malignant potential of thyroid nodules is a crucial subject, leading the decision for surgery. Ultrasonography and fine-needle aspiration cytology are pivotal examinations in the diagnostic process, with ultrasonography demonstrating better negative predictive value.

A Rare Manifestation of Secondary Hyperparathyroidism Due to Brown Tumors: A Case Report.

Purpose: Brown tumors, also known as cystic fibrosa, are rare, benign, osteolytic, fibrotic lesions of the bones that occur secondary to hyperparathyroidism. They are caused by increased osteoclastic activity leading to an abnormal bone metabolism. Case Description: Here, we present the case of a 58-year-old male, who presented with painful bony lesions, initially attributed to metastatic disease. After biochemical workout, imaging and biopsy, the nature of the lesions was revealed. We discuss the differential diagnosis and clinical management of the disease. Conclusion: Patients with brown tumors should be assessed in the differential diagnosis of bony lesions and should always be tested for hyperparathyroidism. An early diagnosis is crucial for the successful treatment of such patients.

Pancreatic Vasoactive Intestinal Peptide-Producing Tumor as a Rare Cause of Acute Diarrhea and Severe Hypokalemia.

Pancreatic vasoactive intestinal peptide-producing tumor (VIPoma) is a rare functional neuroendocrine tumor most commonly presenting with watery diarrhea and electrolyte abnormalities that include hypokalemia, hypercalcemia and metabolic acidosis. This type of tumor has usually insidious clinical behavior that is characterized by chronic secretory diarrhea, lasting usually from months to years before diagnosis, not responsive to usual medical or dietary treatment approaches. Given the resemblance of VIPoma with other more common causes of chronic watery diarrhea, the final diagnosis is often delayed and the tumors are usually large and metastatic at the time of detection. Our case of pancreatic VIPoma demonstrates an unusual clinical course for this type of tumor with acute refractory diarrhea and rapid deterioration of patient's clinical and biochemical status that required emergent in-hospital diagnosis and treatment. Our patient is a 45-year-old woman who presented with abrupt, watery diarrhea during the past 24 h before admission accompanied with severe hypokalemia as well as hyponatremia, hyperglycemia and hypercalcemia. Despite aggressive management with fluid administration and electrolyte replenishment, no significant improvement in patient's symptoms and electrolyte imbalance was observed. After exclusion of other causes of acute diarrhea from the medical history and the laboratory tests, the clinical suspicion of a functional neuroendocrine tumor was raised. After the establishment of final diagnosis of pancreatic VIPoma with biochemical tests and magnetic resonance imaging (MRI), somatostatin analogues were prescribed and the patient underwent distal pancreatectomy and splenectomy with no signs of lymph node and splenic metastases. Few days after the surgical resection of the tumor, the patient readmitted to our hospital with tarry stools and severe anemia. The abdominal computed tomography (CT) revealed a retroperitoneal cystic lesion. The gastrointestinal bleeding gradually recessed after endoscopic hemostasis of duodenal ulcer lesions whereas the cystic lesion (postoperative lymphocele) was successfully drained under CT-guidance before discharge. After almost 10 years postoperatively, the patient is still asymptomatic with no signs of relapse or metastasis of the disease in the periodic laboratory and imaging follow-up. In conclusion, pancreatic VIPoma can sometimes manifest symptoms of abrupt onset and rapid progression that require high clinical suspicion, appropriate diagnostic workup and aggressive management.

Biomarkers in neuroendocrine neoplasms.

Neuroendocrine tumors are a heterogenous group of rare neoplasms with different morphological features, immunophenotype, molecular profile, and clinical presentation. They can derive from any neuroendocrine cell throughout the body, but the majority of NENs is developed in the gastrointestinal tract. They can be divided into two groups, based on hormone secretion, functioning and non-functioning NENs. The first group is characterised from the secretion of specific substances, defining the clinical manifestations. Functional NENs can be divided into carcinoid tumors, with serotonin overproduction, and functional GEP NEN's (mostly located in pancreas) that may secrete insulin, VIP, gastrin, glucagon or somatostatin. Non-functioning NENs, comprise approximately 85% of NEN's. As these tumors lack specific symptoms, they come to clinical attention later, when they have a large size or metastases. Apart from the specific biomarkers that functional NENs are producing, there are some general markers that are produced from all NENs and play a major role in the diagnosis, prognosis and follow up of these patients. These are chromogranin (CgA), neuron-specific enolase (NSE) and 5-hydroxyindolic acetic acid (5-HIAA).

Carcinoid syndrome-Symptoms and therapeutic approaches.

The carcinoid syndrome (CS) is a constellation of symptoms attributed to hypersecretion of amines, prostaglandins and polypeptides. The cardinal symptoms of CS are flushing, diarrhea and bronchospasm; however, CS may present with various symptoms and signs, as: Skin: cutaneous flushes, cyanosis, pellagra, Gastrointestinal: diarrhea, nausea, abdominal cramps, vomiting, Heart: tricuspid and pulmonic valve thickening causing right heart failure, edema, Respiratory: wheezing, dyspnea.

The Role of Somatostatin Analogues in the Control of Diarrhea and Flushing as Markers of Carcinoid Syndrome: A Systematic Review and Meta-Analysis.

BACKGROUND: Somatostatin analogues (SSAs) are the cornerstone of treatment for carcinoid syndrome (CS)-related symptoms. The aim of this systematic review and meta-analysis is to evaluate the percentage of patients achieving partial (PR) or complete response (CR) with the use of long-acting SSAs in patients with CS. METHODS: A systematic electronic literature search was conducted in PubMed, Cochrane, and Scopus to identify eligible studies. Any clinical trials reporting data on the efficacy of SSAs to alleviate symptoms in adult patients were considered as potentially eligible. RESULTS: A total of 17 studies reported extractable outcomes (PR/CR) for quantitative synthesis. The pooled percentage of patients with PR/CR for diarrhea was estimated to be 0.67 (95% confidence interval (CI): 0.52-0.79, I2 = 83%). Subgroup analyses of specific drugs provided no evidence of a differential response. With regards to flushing, the pooled percentage of patients with PR/CR was estimated to be 0.68 (95% CI: 0.52-0.81, I2 = 86%). Similarly, no evidence of a significant differential response in flushing control was documented. CONCLUSIONS: We estimate there is a 67-68% overall reduction in symptoms of CS associated with SSA treatment. However, significant heterogeneity was detected, possibly revealing differences in the disease course, in management and in outcome definition.

Age-dependent and sex-dependent disparity in mortality in patients with adrenal incidentalomas and autonomous cortisol secretion: an international, retrospective, cohort study.

BACKGROUND: The association between cortisol secretion and mortality in patients with adrenal incidentalomas is controversial. We aimed to assess all-cause mortality, prevalence of comorbidities, and occurrence of cardiovascular events in uniformly stratified patients with adrenal incidentalomas and cortisol autonomy (defined as non-suppressible serum cortisol on dexamethasone suppression testing). METHODS: We conducted an international, retrospective, cohort study (NAPACA Outcome) at 30 centres in 16 countries. Eligible patients were aged 18 years or older with an adrenal incidentaloma (diameter ≥1 cm) detected between Jan 1, 1996, and Dec 31, 2015, and availability of a 1 mg dexamethasone suppression test result from the time of the initial diagnosis. Patients with clinically apparent hormone excess, active malignancy, or follow-up of less than 36 months were excluded. Patients were stratified according to the 0800-0900 h serum cortisol values after an overnight 1 mg dexamethasone suppression test; less than 50 nmol/L was classed as non-functioning adenoma, 50-138 nmol/L as possible autonomous cortisol secretion, and greater than 138 nmol/L as autonomous cortisol secretion. The primary endpoint was all-cause mortality. Secondary endpoints were the prevalence of cardiometabolic comorbidities, cardiovascular events, and cause-specific mortality. The primary and secondary endpoints were assessed in all study participants. FINDINGS: Of 4374 potentially eligible patients, 3656 (2089 [57·1%] with non-functioning adenoma, 1320 [36·1%] with possible autonomous cortisol secretion, and 247 [6·8%] with autonomous cortisol secretion) were included in the study cohort for mortality analysis (2350 [64·3%] women and 1306 [35·7%] men; median age 61 years [IQR 53-68]; median follow-up 7·0 years [IQR 4·7-10·2]). During follow-up, 352 (9·6%) patients died. All-cause mortality (adjusted for age, sex, comorbidities, and previous cardiovascular events) was significantly increased in patients with possible autonomous cortisol secretion (HR 1·52, 95% CI 1·19-1·94) and autonomous cortisol secretion (1·77, 1·20-2·62) compared with patients with non-functioning adenoma. In women younger than 65 years, autonomous cortisol secretion was associated with higher all-cause mortality than non-functioning adenoma (HR 4·39, 95% CI 1·93-9·96), although this was not observed in men. Cardiometabolic comorbidities were significantly less frequent with non-functioning adenoma than with possible autonomous cortisol secretion and autonomous cortisol secretion (hypertension occurred in 1186 [58·6%] of 2024 patients with non-functioning adenoma, 944 [74·0%] of 1275 with possible autonomous cortisol secretion, and 179 [75·2%] of 238 with autonomous cortisol secretion; dyslipidaemia occurred in 724 [36·2%] of 1999 patients, 547 [43·8%] of 1250, and 123 [51·9%] of 237; and any diabetes occurred in 365 [18·2%] of 2002, 288 [23·0%] of 1250, and 62 [26·7%] of 232; all p values <0·001). INTERPRETATION: Cortisol autonomy is associated with increased all-cause mortality, particularly in women younger than 65 years. However, until results from randomised interventional trials are available, a conservative therapeutic approach seems to be justified in most patients with adrenal incidentaloma. FUNDING: Deutsche Forschungsgemeinschaft, Associazione Italiana per la Ricerca sul Cancro, Università di Torino.

Thyroid sarcoidosis: a rare entity in the differential diagnosis of thyroid cancer.

SUMMARY: We present two cases of thyroid sarcoidosis that were misdiagnosed as thyroid cancer. In the first patient, fine needle aspiration cytology (FNAc) of a suspicious thyroid nodule indicated the presence of papillary thyroid cancer, and the patient underwent thyroid surgery. However, histopathology identified a sarcoid granuloma, without any sign of malignancy. The second patient had a history of papillary microcarcinoma with suspicious lymph nodes diagnosed years after the initial diagnosis and was referred for assessment of cervical lymphadenopathy. Fine needle aspiration cytology (FNAc) of the suspicious lymph nodes erroneously indicated metastasis from thyroid cancer, and lateral modified lymph node dissection was performed, based on FNAc and ultrasonographic features. Histopathology excluded malignancy and identified non-caseating granulomas. Sarcoidosis of the thyroid may have a clinical presentation similar to well-differentiated thyroid carcinoma and, although rare, should be considered in the differential diagnosis, especially when other signs of the disease are already present. In these cases, FNAc provided a false diagnosis of papillary thyroid carcinoma and lymph node metastases that led to unnecessary surgery. LEARNING POINTS: Sarcoidosis may share clinical and ultrasonographic features with papillary thyroid carcinoma. Fine needle aspiration cytology is helpful in the diagnosis of both conditions; however, the overlapping cytological characteristics may lead to erroneous diagnosis. The present cases illustrate the importance of cytological identification of these difficult cases. Every piece of information provided by the clinician is essential to the cytologist.

ENSAT registry-based randomized clinical trials for adrenocortical carcinoma.

Adrenocortical carcinoma (ACC) is an orphan disease lacking effective systemic treatment options. The low incidence of the disease and high cost of clinical trials are major obstacles in the search for improved treatment strategies. As a novel approach, registry-based clinical trials have been introduced in clinical research, so allowing for significant cost reduction, but without compromising scientific benefit. Herein, we describe how the European Network for the Study of Adrenal Tumours (ENSAT) could transform its current registry into one fit for a clinical trial infrastructure. The rationale to perform randomized registry-based trials in ACC is outlined including an analysis of relevant limitations and challenges. We summarize a survey on this concept among ENSAT members who expressed a strong interest in the concept and rated its scientific potential as high. Legal aspects, including ethical approval of registry-based randomization were identified as potential obstacles. Finally, we describe three potential randomized registry-based clinical trials in an adjuvant setting and for advanced disease with a high potential to be executed within the framework of an advanced ENSAT registry. Thus we, therefore, provide the basis for future registry-based trials for ACC patients. This could ultimately provide proof-of-principle of how to perform more effective randomized trials for an orphan disease.

Intrathyroidal parathyroid adenoma mimicking thyroid cancer.

Primary hyperparathyroidism (PHPT) is the most common cause of hypercalcemia; patients are usually asymptomatic and the cause in 80-85% of cases is a single parathyroid adenoma (PA). Parathyroid adenomas arise from clonal expansion of tumor cells and may be located either posteriorly to the thyroid lobes or in ectopic sites. The incidence of intrathyroidal PAs varies from 1% to 6% and although uncommon, they pose certain diagnostic difficulties which may complicate treatment. The identification of the adenoma requires a combination of clinical evidence, imaging information and cytological findings due to the challenging distinction between thyroid and parathyroid lesions. We present the case of a patient with a large, partially cystic intrathyroidal parathyroid adenoma which was initially identified as a malignant thyroid nodule. We discuss the caveats that present in these rare cases and the important clinical and histological features that aid in the final diagnosis. In the case of our patient the cytological similarities between thyroid malignant cells and parathyroid cells, in combination with the negative sestamibi scan, resulted in a more invasive surgery than that a single parathyroid adenoma would require. Clinicians need to be vigilant in terms of the similarities between parathyroid and thyroid cytology in order to provide optimal patient care in these rare cases.

Malignant Pheochromocytomas/Paragangliomas and Ectopic Hormonal Secretion: A Case Series and Review of the Literature.

Malignant pheochromocytomas (PCs) and paragangliomas (PGLs) are rare neuroendocrine neoplasms defined by the presence of distant metastases. There is currently a relatively paucity of data regarding the natural history of PCs/PGLs and the optimal approach to their treatment. We retrospectively analyzed the clinical, biochemical, imaging, genetic and histopathological characteristics of fourteen patients with metastatic PCs/PGLs diagnosed over 15 years, along with their response to treatment. Patients were followed-up for a median of six years (range: 1-14 years). Six patients had synchronous metastases and the remaining developed metastases after a median of four years (range 2-10 years). Genetic analysis of seven patients revealed that three harbored succinate dehydrogenase subunit B/D gene (SDHB/D) mutations. Hormonal hypersecretion occurred in 70% of patients; normetanephrine, either alone or with other concomitant hormones, was the most frequent secretory component. Patients were administered multiple first and subsequent treatments including surgery (n = 12), chemotherapy (n = 7), radionuclide therapy (n = 2) and radiopeptides (n = 5). Seven patients had stable disease, four had progressive disease and three died. Ectopic hormonal secretion is rare and commonly encountered in benign PCs. Ectopic secretion of interleukin-6 in one of our patients, prompted a literature review of ectopic hormonal secretion, particularly from metastatic PCs/PGLs. Only four cases of metastatic PC/PGLs with confirmed ectopic secretion of hormones or peptides have been described so far.

Patients with extra-adrenal malignancies and adrenal lesions have similar rates of subclinical hypercortisolism compared with patients with true adrenal incidentalomas.

OBJECTIVE: During follow-up in cancer patients, adrenal lesions are frequently found by computer tomography imaging. In these patients, the frequency of subclinical Cushing's syndrome (SCS) has not been fully explored. The aim of the present study was to investigate the presence of SCS in cancer patients with adrenal lesions in comparison to patients with true adrenal incidentalomas. DESIGN: We studied 95 patients with adrenal lesions: 57 patients (group A, 20 males and 37 females) had a history of extra-adrenal malignancy and adrenal lesions were discovered during staging of the primary cancer, and 38 patients (group B, 6 males and 32 females) had adrenal incidentalomas. The two groups had similar BMI. All patients had unenhanced HU < 10 in computed tomography to ensure low risk of adrenal metastatic disease. Patients' morning plasma cortisol levels and ACTH were measured. An overnight 1 mg dexamethasone suppression test (ODST) was performed in all participants; in case of abnormal results, 24-h urine cortisol and the low-dose dexamethasone suppression test were additionally conducted. The cutoffs of morning cortisol values used for ODST were 1.8 and 5 µg/dl. RESULTS: When the cutoff of 1.8 µg/dl for suppressed morning cortisol was used, 42.1% of group A and 39.5% of group B had abnormal results (p = 0.95). By using the threshold of 5 µg/dl after ODST, 5.3% of group A and 13.2% of group B did not have suppressed cortisol levels with the 1 mg ODST (p = 0.18). The main factors found to influence suppressed cortisol levels after ODST in both groups were BMI and size of the adrenal lesion. CONCLUSIONS: Patients with extra-adrenal malignancies and adrenal lesions had similar rates of subclinical hypercortisolemia compared to patients with true adrenal incidentalomas.

Loss of Efficacy of Pasireotide After its Re-Administration: is There a Reason Why?

Pasireotide is a recently approved medical treatment for persistent or recurrent Cushing's disease (CD). However, an escape from the initial successful response has not yet been described. A 42-year-old female presented with several symptoms indicative of hypercortisolism. Biochemical evaluation and imaging were consistent with CD due to a pituitary adenoma. Surgical excision of the adenoma was unsuccessful and gamma-knife radiosurgery was followed. Our patient remained hypercortisolemic thus treatment with pasireotide (900 mg subcutaneously twice daily) was decided. Biochemical and clinical remission was noted shortly thereafter. Moderate adverse events led to dose reduction to 600 mg subcutaneously twice daily. The patient remained in remission for 6 months, when treatment was discontinued due to cholecystitis. One month after cholecystectomy, pasireotide was restarted with no clinical or biochemical benefit that time. Pasireotide is an effective medical treatment for CD. Nevertheless, a loss of its initial efficacy may rarely be described.

Treatment compliance and severe adverse events limit the use of tyrosine kinase inhibitors in refractory thyroid cancer.

OBJECTIVE: The aim of the present study was to assess patient compliance with tyrosine kinase inhibitor (TKI) treatment used for refractory and progressive thyroid cancer, in addition to the efficacy and serious adverse events associated with these agents. METHODS: We retrospectively analyzed data from adult patients with metastatic differentiated or medullary thyroid cancer unresponsive to conventional treatment and treated with TKIs. Patients received treatment until disease progression or onset of serious adverse events, or until they expressed an intention to stop treatment. RESULTS: Twenty-four patients received TKIs. The median duration of treatment was four (range: 1-19) cycles. The most frequent adverse events were fatigue, nausea, diarrhea, hypertension, and stomatitis, and the most severe were nasal bleeding, diarrhea, heart failure, rhabdomyolysis, renal failure, QT prolongation, neutropenia, and severe fatigue. Dose reduction was required in eight patients, while five decided to terminate TKI therapy because adverse events impaired their everyday activities. During therapy, two patients showed a partial response and three showed stable disease. The lungs were the metastatic sites favoring a response to treatment. CONCLUSION: Patient selection and meticulous pretreatment education are necessary in order to ensure adherence with TKI therapy. If adverse events appear, dose reduction or temporary treatment interruption may be offered because some adverse events resolve with continuation of treatment. In the event of serious adverse events, treatment discontinuation is necessary.

Breast Metastasis from Medullary Thyroid Carcinoma in a Male Patient: Case Report and Review of the Literature.

Medullary thyroid carcinoma (MTC) is a rare malignancy that may metastasize to liver, lungs and bones. Breast is an unusual metastatic site for MTC and only 20 female cases have been reported in the literature. We present a male patient in whom histological examination and immunohistochemistry of a breast mass were indicative of breast metastasis from MTC. A 67-year-old man with recent diagnosis of MTC and metastases to cervical and upper mediastinum lymph nodes was referred to our department for further treatment. At first evaluation, diagnostic imaging techniques showed lung and bone metastases and three months later the presence of liver metastases. Due to the extension of the disease, treatment with vandetanib was decided, but serious adverse events led to its interruption after two weeks. During follow-up, patient developed a painful swelling in the right breast. Ultrasound and mammography showed the presence of multiple masses to the right breast suspicious for malignancy. Core needle biopsy and histological examination of the specimen confirmed the presence of metastatic MTC. Palliative external beam irradiation was used to relieve local pain and, after one month, the patient died. Consequently, breast masses should be cautiously evaluated, mainly in the presence of a known primary malignancy. Histological and/or cytopathological examination are requisite diagnostic tools, while external beam irradiation and tyrosine kinase inhibitors may be used as palliative therapies in the concurrent presence of breast metastases from MTC.

Pituitary disorders in pregnancy.

The pituitary gland is significantly affected during gestation in terms of both size and function. Due to this physiologic adaptation, endocrine evaluation and interpretation of imaging is far more complex than in the non-pregnant state. Pituitary disorders are rare in pregnancy, as they are usually associated with gonadal dysfunction, thereby posing difficulties with fertility. This review will focus on pituitary adenomas (prolactinomas, GH-secreting and ACTH-secreting), their diagnostic handicaps and the recommendations for treatment. We will also discuss the two pituitary disorders encountered in pregnancy, Sheehan's syndrome and lymphocytic hypophysitis.

Predictive factors that influence the course of medullary thyroid carcinoma.

BACKGROUND: Medullary thyroid cancer (MTC) is an infrequent form of thyroid cancer. We aimed to examine how gender and histological characteristics influence the rate of recurrence/persistent disease, distant metastases and survival and also to define specific characteristics of MTC microcarcinomas. METHODS: The medical records of 85 patients with MTC were reviewed. The following characteristics were recorded: year of diagnosis, age at diagnosis, sex, tumor size, number of tumor foci, lymph node metastases, thyroid capsule and vascular invasion, infiltration of thyroid parenchyma and extrathyroid extension, and distant metastases. RESULTS: During follow-up (mean 78.8 months), persistent disease occurred in 40 patients, local recurrences in 5 and distant metastases in 32 patients. Local and distant disease appeared more frequently in patients with larger tumors (p < 0.005) and lymph node metastases (p < 0.01). In addition, patients with invasive tumors had local and distant disease more frequently. The percentage of males who had persistent disease and/or local recurrence was significantly higher than the percentage of males who did not (p < 0.05). Similar results were observed for distant disease (p < 0.01). Independent predictors of recurrence and persistent disease was the presence of lymph node metastases at diagnosis (risk ratio 11.66) and of distant metastases were the presence of lymph node metastases at diagnosis (risk ratio 17.42) and the presence of vascular invasion (risk ratio 2.41). Fifteen patients died due to MTC during follow-up (17.6 %). Patients who died were more frequently males, and had thyroid capsule invasion, extrathyroidal extension, vascular invasion and metastatic disease. CONCLUSIONS: Male sex, tumor size and invasive characteristics of the tumor are negative predictive factors for evolution of MTC.