Medullary thyroid cancer

Metastatic lymph node ratio can further stratify risk for mortality in medullary thyroid cancer patients: A population-based analysis

Medullary thyroid cancer (MTC) has a propensity to cervical lymph node metastases (LNM). Recent studies have shown that both the number of involved lymph nodes (LNs) and the metastatic lymph node ratio (MLNR) confer prognostic information. This study was to determine the predictive value of MLNR on cancer-specific survival (CSS) in SEER (Surveillance, Epidemiology and End Results)-registered MTC patients treated with thyroidectomy and lymphadenectomy between 1991 and 2012, investigate the cutoff points for MLNR in stratifying risk of mortality and provide evidence for selection of appropriate treatment strategies. X-tile program determined 0.5 as optimal cut-off value for MLNR in terms of CSS in 890 MTC patients. According to multivariate Cox regression analysis, MLNR (0.50–1.00) is a significant independent prognostic factor for CSS (hazard ratio 2.161, 95% confidence interval 1.327–3.519, p=0.002). MLNR (0.50–1.00) has a greater prognostic impact on CSS in female, non-Hispanic white, T3/4, N1b and M1 patients. The lymph node yield (LNY) influences the effect of MLNR on CSS; LNY ≥9 results in MLNR (0.50–1.00) having a higher HR for CSS than MLNR (0.00-0.49). In conclusion, higher MLNRs predict poorer survival in MTC patients. Eradication of involved nodes ensures accurate staging and maximizes the ability of MLNR to predict prognosis.

Prognostic significance and optimal cutoff of age in medullary thyroid cancer

Age has been found to correlate with the prognosis for medullary thyroid cancer (MTC). This study was conducted to investigate whether age can predict long-term unfavorable prognosis and evaluate its predictive accuracy associated with TNM staging, using data of patients diagnosed with MTC between 2000 and 2010 from Surveillance, Epidemiology and End Results database. The relationship between the patients' age at diagnosis and cancer-specific survival (CSS) was evaluated using multivariate Cox regression analysis. Age stratifications were combined into a nomogram model to predict the CSS of MTC. The X-tile program determined 49 and 69 as optimal age cutoff values for CSS. On multivariate analysis, independent factors for survival were age (50-69 years, HR 2.853, 95% CI 1.631-4.991; ≥70 years, HR 5.804, 95% CI 2.91-11.555), race (white, HR 0.344, 95% CI 0.188-0.630), T (T3/4, HR 3.931, 95% CI 2.093-7.381), N (N1a, HR 3.269, 95% CI 1.386-7.710) and M (M1, HR 3.998, 95% CI 2.419-6.606). The C-index for CSS prediction with TNM, age (cutoff of 45)/sex/race/TNM and age (cutoff of 49 and 69)/sex/race/TNM were 0.832 (95% CI 0.763-0.901), 0.863 (95% CI 0.799-0.928), and 0.876 (95% CI 0.817-0.935), respectively. Subgroup multivariate analyses also showed that age significantly increased the risk for CSS in females, non-Hispanic white patients, and those with stage IV MTC. In conclusion, CSS was independently associated with ages between 49 and 69 years, which might be applied for risk stratification in MTC patients.

Recurrent spinal metastasis of a sporadic medullary carcinoma of the thyroid after radiation therapy: a case report and review of the literature

Sporadic Medullary Carcinoma of the Thyroid is a relatively uncommon entity and at the time of diagnosis, most already present loco-regional metastasis. Therapy should be aggressive to reduce recurrence and mortality. Follow-up period should continue lifelong and should also include calcium/pentagastrin infusion test, as well as 6-month interval diagnostic imaging.

Surgical management of thyroid cancer

Thyroid cancer is the most common endocrine neoplasm; however, it only accounts for less than 1% of all human malignances. Thyroid cancers are divided into well differentiated and non-well differentiated cancers, according to their histology and behavior. The surgical management options of well-differentiated thyroid cancer include total or near-total thyroidectomy, subtotal thyroidectomy and lobectomy plus isthmusectomy. The extent of surgery for thyroid cancer continues to be an area of controversy. Complications associated with thyroid surgery are directly proportional to the extent of thyroidectomy and inversely proportional to the experience of the operating surgeon. They occur less frequently with good surgical technique and better understanding of surgical anatomy, and include wound healing and infections (seroma, hematoma and wound infection), nerve injury, hypoparathyroidism, hypothyroidism, postoperative hemorrhage and respiratory obstruction.

Medullary thyroid carcinoma: surgical treatment advances

Since medullary thyroid cancer (MTC) was first recognized as a distinct tumor in 1959, it became clear that MTC is more difficult to cure than papillary thyroid cancer and has higher rates of recurrence and mortality. MTC represents 5-8% of thyroid cancers. It derives from parafollicular cells of the ultimobranchial body derived from the neural crest. MTC secretes calcitonin and other hormonal peptides and is considered part of the amine precursor uptake and decarboxilation system. MTC may occur either as a hereditary or nonhereditary entity. Hereditary MTC can occur either alone as the familial MTC or as the thyroid manifestation of multiple endocrine neoplasia (MEN) type 2 syndromes (MEN 2A MEN 2B). Activating point mutations of the RET proto-oncogene have demonstrated to be causative of the familial form of medullary thyroid cancer, both isolated familial MTC and associated with MEN 2A and 2B. In the last 10 years, major improvements and new technologies have been proposed and applied in thyroid surgery; among these are molecular diagnosis with genetic screening and mini-invasive video-assisted thyroidectomy. The history of thyroid surgery starts with Billroth, Kocher and Halsted, who developed the technique for thyroidectomy between 1873 and 1910. Prophylactic surgery for patients carrying a positive RET proto-oncogene has proven to be highly effective in curing those likely to experience the development of MTC. Video-assisted procedures with central compartment dissection have proved feasible for patients carrying a positive RET proto-oncogene. This paper reviews relevant medical literature published in the English language on surgery of MTC in well-controlled trials. We discuss the particular ethical and legal issues that thyroid prophylactic surgery raises. Searches were last updated in February 2007.

MicroRNA profiling of sporadic and hereditary medullary thyroid cancer identifies predictors of nodal metastasis, prognosis, and potential therapeutic targets

PURPOSE

While the molecular basis of hereditary medullary thyroid cancer (HMTC) has been well defined, little is known about the molecular pathogenesis of sporadic medullary thyroid cancer (SMTC). In addition, microRNAs (miRNAs) have been shown to be important diagnostic and prognostic markers in cancer but have not been defined in MTC. Our aim was to study the miRNA profile of MTC to identify prognostic biomarkers and potential therapeutic targets.

EXPERIMENTAL DESIGN

MiRNA microarray profiling was carried out in fresh frozen tissues from patients with SMTC (n = 12) and HMTC (n = 7). Differential expression of three miRNAs was confirmed in a validation cohort of SMTC and HMTC samples (n = 45) using quantitative reverse transcriptase-PCR and correlated with clinical outcomes. The functional role of a selected miRNA was investigated in vitro in the human medullary thyroid carcinoma cell line (TT cells) using cell proliferation assays and Western blotting analysis.

RESULTS

MiRs-183 and 375 were overexpressed (P = 0.001; 0.031) and miR-9* was under-expressed (P = 0.011) in SMTC versus HMTC. Overexpression of miRs-183 and 375 in MTC predicted lateral lymph node metastases (P < 0.001; P = 0.001) and was associated with residual disease (P = 0.001; 0.003), distant metastases (P = 0.003; 0.001), and mortality (P = 0.01; 0.011). Knock down of miR-183 expression in the TT cell line induced a significant decrease in the viable cell count and upregulation of the protein LC3B, which is associated with autophagy.

CONCLUSIONS

Our data indicate that miRNAs play a pivotal role in the biology of MTC and represent an important class of prognostic biomarkers and therapeutic targets warranting further investigation.

Medullary thyroid carcinoma: long-term outcomes of surgical treatment

BACKGROUND

Medullary thyroid carcinoma (MTC) accounts for 5 to 10% of all thyroid cancers but is responsible for a disproportionate number of deaths.

METHODS

We performed a retrospective review to describe clinical outcomes in patients with medullary thyroid carcinoma, screening a subset of patients for somatic mutations in the RET and p18 genes and performing genotype-phenotype correlation in a tertiary-care referral hospital from 1967 to 2009.

RESULTS

We studied a total of 94 patients identified from a prospectively maintained thyroid cancer database. Data gathered included patient demographics, serum calcitonin, clinical outcomes, histopathology, genetic analysis, and status at final follow-up. A subset cohort (n = 50) was screened for somatic mutations in the RET gene and the three exons of the p18 gene. The subset cohort was composed of hereditary medullary thyroid carcinoma (HMTC) (n = 19, index patients = 10, screen detected = 9) and sporadic medullary thyroid carcinoma (SMTC) (n = 31). There were no mutations in the p18 gene in the subset cohort.

CONCLUSIONS

A total of 67 SMTC and 27 (28.7%) HMTC cases identified. SMTC were older at initial presentation (52 vs. 34, P = 0.003), had higher preoperative serum calcitonin levels (7968 vs. 1346 ng/L, P = 0.008), and had lymph node recurrence (P = 0.001) compared to HMTC. The tumors were smaller in HMTC (P = 0.038). Overall 10-year survival in SMTC versus HMTC was 69 versus 93% (P = 0.12). On multivariate analysis, vascular invasion (hazard ratio 6.4, P = 0.019) was an adverse predictor for disease-free survival. HMTC in the era of RET analysis presents with a smaller primary tumor, lower preoperative serum calcitonin levels, and lower rates of lymph node metastasis. Mutations in the p18 gene were not a major factor in medullary thyroid carcinoma tumorigenesis.

Sporadic medullary thyroid carcinoma: clinical data from a university hospital

INTRODUCTION

Medullary thyroid carcinoma may occur in a sporadic (s-medullary thyroid carcinoma, 75%) or in a multiple endocrine neoplasia type 2 form (MEN2, 25%). These clinical forms differ in many ways, as s-medullary thyroid carcinoma cases are RET-negative in the germline and are typically diagnosed later than medullary thyroid carcinoma in MEN2 patients. In this study, a set of cases with s-medullary thyroid carcinoma are documented and explored.

PURPOSE

To document the phenotypes observed in s-medullary thyroid carcinoma cases from a university group and to attempt to improve earlier diagnosis of s-medullary thyroid carcinoma. Some procedures for diagnostics are also recommended.

METHOD

Patients (n=26) with apparent s-medullary thyroid carcinoma were studied. Their clinical data were reviewed and peripheral blood was collected and screened for RET germline mutations.

RESULTS

The average age at diagnosis was 43.9 years (+/- 10.82 SD) and did not differ between males and females. Calcitonin levels were increased in all cases. Three patients presented values that were 100-fold greater than the normal upper limit. Most (61.54%) had values that were 20-fold below this limit. Carcinoembryonic antigen levels were high in 70.6% of cases. There was no significant association between age at diagnosis, basal calcitonin levels or time of disease onset with thyroid tumor size (0.6-15 cm). Routine thyroid cytology yielded disappointing diagnostic accuracy (46.7%) in this set of cases. After total thyroidectomy associated with extensive cervical lymph node resection, calcitonin values remained lower than 5 pg/mL for at least 12 months in eight of the cases (30.8%). Immunocyto- and histochemistry for calcitonin were positive in all analyzed cases. None of the 26 cases presented germline mutations in the classical hotspots of the RET proto-oncogene.

CONCLUSION

Our cases were identified late. The basal calcitonin measurements and immunostaining for calcitonin were highly useful for diagnosing s-medullary thyroid carcinoma. The rate of complete patient recovery was low, and none of the parameters analyzed were useful predictors of the thyroid tumor size. Our findings support previous recommendations for routine serum calcitonin evaluation and immunostaining analysis involving single thyroid nodules.

Neck management in medullary thyroid carcinoma

AIMS

The aims of this study were to retrospectively evaluate incidence and patterns of lymph node metastases, surgical treatment and prognostic factors of medullary thyroid carcinoma.

METHODS

Out of a group of 70 MTC patients data of 67 patients were collected. Sixty-two of these patients underwent surgery. Apart from thyroidectomy, 16 patients underwent a bilateral neck dissection, 21 a unilateral neck dissection and 29 a paratracheal dissection or node-picking operation. Thirty-six patients were irradiated, of which 31 postoperatively and five with palliative intent.

RESULTS

Lymph node metastases were found in 91% of the ipsilateral neck dissection specimens, 91% of the paratracheal dissections and 63% of the contralateral dissections. Of the 12 elective neck dissections, 5 were tumor positive. Level VI was positive in 91% of the cases where a dissection was done, whereas preoperatively only 16% were scored tumor positive. During follow-up 22 of the 67 patients developed one or more locoregional recurrences (in total 28 recurrences). The most important factors that were correlated with a worse prognosis of survival were late stage of disease (stage III and IV) (p=0.0014), high number of positive lymph nodes (p=0.0023) and incomplete surgical resection (p=0.0002).

CONCLUSIONS

The high rate of locoregional recurrences in this study are a strong argument for a more aggressive approach to the primary and neck. A routine central and ipsilateral selective neck dissection of levels II-V should be considered in all MTC patients based on the high incidence of metastases and the relative low morbidity of a unilateral neck dissection. Patients referred after thyroidectomy alone with elevated (stimulated) calcitonin levels should be re-operated, performing an elective or therapeutic central and unilateral neck dissection.

Locoregional control in patients with palpable medullary thyroid cancer: results of standardized compartment-oriented surgery

BACKGROUND

Extent of neck dissection is controversial in patients with palpable medullary thyroid cancer (MTC).

METHODS

We evaluated 64 MTC patients (19 hereditary, 45 sporadic) with palpable thyroid nodules (group 1, n = 35) or palpable lymph node metastases (group 2, n = 29). Standard surgery included total thyroidectomy, central compartment dissection, and additional neck dissection on indication.

RESULTS

In group 1, 40% of the patients were cured. Thirty-one percent of all patients had central, 23% ipsilateral, 14% contralateral, and 14% mediastinal, metastases. Fifty-one percent developed locoregional recurrence. Locoregional recurrence (p = .043) and reoperations (p = .020) were noted more often after a less than standard initial procedure. In group 2, no patients were cured. All had central, 93% ipsilateral, 45% contralateral, and 52% mediastinal metastases. Thirty-eight percent developed locoregional recurrence.

CONCLUSIONS

Locoregional recurrence frequently occurs in palpable MTC, and tumor control may be improved by standard central, bilateral, and upper mediastinal neck dissection.

Late-Onset Medullary Carcinoma of the Thyroid: Need for Genetic Testing and Prophylactic Thyroidectomy in Adult Family Members

OBJECTIVE

Sporadic late-onset medullary carcinoma of the thyroid is quite rare. Usually, the patient presents with a thyroid mass or neck node metastasis along with high levels of calcitonin and preoperative fine needle aspiration biopsy suggestive of medullary carcinoma of the thyroid. The role of genetic testing in such individuals, along with testing of other family members, remains somewhat unclear at this stage, especially in patients presenting with familial medullary thyroid carcinoma. Genetic testing with RET proto-oncogene mutational studies is very popular in familial medullary thyroid carcinoma, especially in children, with routine prophylactic thyroidectomy. However, its indications in adults remain unclear at this time.

CASE STUDY

Recently, a 69-year-old woman presented with a thyroid mass and underwent total thyroidectomy and central compartment dissection. She was found to have medullary carcinoma of the thyroid. The patient had four children, three of whom were found to have a RET mutation similar to their mother's, V804M. In view of the RET mutation, the three children were offered prophylactic thyroidectomy at ages 42, 45, and 47. The patient's son was noted to have extensive C-cell hyperplasia in both lobes of the thyroid. The other two individuals had benign pathology with no evidence of C-cell hyperplasia.

CONCLUSIONS

There is no definite consensus of opinion about the need for prophylactic total thyroidectomy in adults with RET mutation. The rarely reported 804 mutation is, however, a predictor of medullary carcinoma of the thyroid. One individual in this group had extensive C-cell hyperplasia, suggesting that he would have developed medullary carcinoma of the thyroid in the future. Prophylactic thyroidectomy should be recommended in patients with RET mutation and a family history of medullary carcinoma of the thyroid; however, its role in adult family members needs to be evaluated with larger registry of prophylactic thyroidectomy. Whether these adults with rare 804-mutation could be observed and followed with serial calcitonin, ultrasound, or calcitonin stimulation tests remains to be studied.

Prognostic factors for sporadic medullary thyroid carcinoma

INTRODUCTION

Medullary thyroid carcinoma (MTC) originates from the thyroid parafollicular cells and accounts for 3% to 10% of all thyroid malignancies. Approximately 84% of cases are sporadic. The aim of this study was to evaluate the outcomes of treatment for sporadic medullary thyroid carcinoma (SMTC) and define the prognostic factors for overall survival.

METHODS

The records of 32 SMTC patients treated at Ankara Oncology Education and Research Hospital between September 1993 and April 2003 were retrospectively evaluated. The effects of age, gender, tumor localization, extent of the primary surgical resection, tumor size, capsule invasion, lymph node metastasis, extranodal extension, tumor stage, local recurrence, and distant metastasis on the overall survival rate were evaluated by univariate and multivariate analyses.

RESULTS

There were 32 patients (19 females, 13 males) with a median age of 45 years (21-76 years). Altogether, 22 patients had undergone complete resection and 10 patients incomplete resection. The median follow-up was 48 months (9-111 months), and the overall 5-year survival rate was 51%. Based on the univariate analysis, the extent of primary surgical resection, pathologic tumor size, capsule invasion, lymph node invasion, extranodal extension, tumor stage, local recurrence, and distant metastasis were factors that significantly affected survival. In the multivariate analysis, however, only the extent of the primary surgical resection, capsule invasion, and distant metastasis were found to be statistically significant factors.

CONCLUSIONS

The extent of the primary surgical resection significantly influences the survival of patients with SMTC. Capsule invasion and distant metastasis were additional factors affecting the prognosis.

[Pre-symptomatic diagnosis of severe hereditary diseases with late onset in Lebanon: a choice or a necessity?]

Progress achieved in the field of molecular genetics has opened the door to pre-symptomatic diagnosis tests of several severe hereditary disease, a majority of which are dominant and appear later in life. Given the importance of diagnosis in some of the cases where medical supervision and prevention are possible, there are a number of ethical dilemmas with regards to most of these diseases that, unfortunately, do not have a cure or any preventive treatment available. Above and beyond the capacity for medical care provision, there is a very high level of pressure and anxiety felt by every member of a family who has someone affected by one of these diseases in that they might be a carrier of a mutated gene which could be the cause or source of illness. They carry the burden of uncertainty that they may have already transmitted this gene or could give it to any of their children, and often there is also a significant level of guilt when one is the carrier but not to be affected by the disease itself. More and more frequently in these types of cases, there is a strong desire to know--in order to better organise and plan one's life and that of one's potential future family in the instance where one wishes to found one. This article discusses these problems based upon the consideration of four examples of such diseases with late onset: Huntington's disease, the common forms of thyroid cancer, the familiar forms of a predisposition to breast and ovarian cancer, and von Hippel-Lindau syndrome. However, regardless of the type of disease, the decision to take a genetic test is solely the choice of the individual in question, and the person should be accompanied and guided in his or her reflection by a multi-disciplinary team who can advise him or her and initiate useful deliberations on the various possibilities, their advantages and their disadvantages.

Thyroid disorders in Brazilian patients with celiac disease

INTRODUCTION/AIM

Patients with celiac disease (CD) can develop a gluten related autoimmune disorder that affects not only the small intestine but other tissues as well. An increased prevalence of autoimmune diseases has been reported, particularly autoimmune thyroiditis. The aim of this study was to characterize thyroid disorders in patients with CD.

PATIENTS/METHODS

Fifty-two patients with CD (43 female, 9 male; mean age, 41.1 years) were studied. Nine were on a gluten-free diet (GFD). They were divided into four groups: Group 1, without thyroid involvement (n=30); Groups 2A-C, with thyroid involvement (n=22); Group 2A, subclinical hypothyroidism (n=11); Group 2B, clinical hypothyroidism (n=10); and Group 2C, other thyroid disorders (n=1). CD was confirmed by serologic and histologic criteria. Thyroid involvement was detected by measurement of thyroid stimulating hormone (TSH) and anti-thyroperoxidase antibodies (anti-TPO).

RESULTS

Increased levels of TSH and/or anti-TPO levels were detected in Groups 2A (21.1%) and 2B (19.2%). The patients of Group 2B presented clinical symptoms of hypothyroidism before the diagnosis of CD, and 5 of these patients were receiving levothyroxine. One woman (Group 2C; 1.92%) had a medullary carcinoma. There was statistical significance between the age when thyroid disease was diagnosed (current age) and the age of CD diagnosis between Groups 1 and 2B. Patients with thyroid involvement presented associated diseases such as diabetes mellitus (2), Down's syndrome (2), ulcerative colitis (1), and dermatitis herpetiformis (2).

CONCLUSIONS

Our findings demonstrated an increased prevalence of thyroid disorders (hypothyroidism, 19.2%; and subclinical hypothyroidism, 21.2%), and other associated diseases in celiac patients, even on a GFD, increasing with the age of the patients. Screening for associated diseases is recommended for patients with CD, independent of age at diagnosis or treatment duration.

Prognostic Variables and Calcitonin in Medullary Thyroid Cancer

OBJECTIVES/HYPOTHESIS

Medullary thyroid cancer (MTC) is a nonepithelial, neuroendocrine tumor with a more aggressive clinical behavior than differentiated thyroid cancer. The purpose of the study was to review a single institution's experience with MCT since 1969.

STUDY DESIGN

Retrospective cohort study.

METHODS

A retrospective review of 30 patients treated for MTC at a tertiary care referral center between 1969 and 2000. There were 17 female and 13 male patients, median age at presentation was 38 years, and median follow-up for survivors was 12.4 years.

RESULTS

Seventy percent of patients had sporadic MTC, 6.7% had familial MTC, 16.7% had multiple endocrine neoplasia syndrome type IIA, and 6.7% had multiple endocrine neoplasia syndrome type IIB. The cumulative overall survival rates at 5, 10, and 20 years were 97%, 88%, and 84%, respectively; disease-free survival rates were 97%, 74%, and 29%, respectively. Advanced tumor stage (P = .014) and multiple endocrine neoplasia syndrome type IIB predicted decreased disease-specific survival. Variables affecting disease-free survival were post-thyroidectomy calcitonin level (P = .001), vascular invasion (P = .005), perineural invasion (P = .010), extrathyroidal extension (P < .001), and the presence of nodal metastases (P = .001). Locoregional control rates were 83% at 5 years and 70% at 10 years. Vascular invasion (P = .004), extrathyroidal extension (P = .008), and post-thyroidectomy basal calcitonin level (P = .003) predicted locoregional failure. Many patients in the series experienced prolonged survival despite elevated calcitonin levels.

CONCLUSION

Long-term disease-free survival is uncommon in MTC, but the study data indicate that the majority of patients with MTC live for prolonged periods, despite biochemical evidence of persistent disease. Adverse pathological features such as extrathyroidal extension and vascular and perineural invasion were predictors of disease recurrence. The use of serum markers in the follow-up of patients with MTC must be interpreted within the clinical context.

Increased expression of mRNA specific for thymidine kinase, deoxycytidine kinase or thymidine phosphorylase in human papillary thyroid carcinoma

The aim of the present study was to estimate the expression of mRNA, specific for thymidine kinase 1 (TK1), deoxycytidine kinase (dCK), and thymidine phosphorylase (dThdPase), i.e. enzymes involved in pyrimidine and purine metabolism in human papillary thyroid carcinoma (PTC) tissue. Additionally, the expression of dCK was estimated, in medullary thyroid carcinoma (MTC). For control, the RNA expression levels for all the enzymes were measured in macroscopically unchanged thyroid tissue. Reverse transcriptase-polymerase chain reaction (RT-PCR) and densitometry were employed for mRNA expression measurements, with the beta-actin gene as a control housekeeping gene. The levels of mRNA expression for TK1, dCK and dThdPase in human PTC, as well as mRNA expression for dCK in MTC, were significantly higher than mRNA expressions for those enzymes found in macroscopically unchanged thyroid tissue. It is concluded that an increased expression of mRNA, specific for TK1, dCK and dThdPase, may be involved in carcinogenic processes in the human thyroid.

[Medullary carcinoma of the thyroid gland (sporadic, familial)]

Medullary thyroid cancer (MTC) is uncommon thyroid tumor with specific characteristics which undoubtedly divide this tumor from other thyroid malignancies. Patients with sporadic or hereditary form of MTC differ in clinical presentation, recurrence of the disease and outcome. The aim of study was to establish surgical characteristics of MTC as well as clinical factors that influence surgical treatment. The study group consisted of 68 patients with MTC managed at the Center for Endocrine Surgery between 1987 and 1999. Retrospective analysis included clinical form of the disease, general data, histological and other tumor characteristics. Mean age of the patients were 47.3 years (female/male ratio: 1.5:1). Mean size of tumor was 80.5 cm3, 72.1% patients had tumor greater than 4 cm. in diameter or extrathyroid spread. The majority of patients were in II and III stadium of the disease. Primary operation (at least total thyroidectomy) was performed in 57 (84%) patients. 2(3%) had postoperatively temporally nerve palsy and 7(10.29%) temporally hypoparathyroidism. The overall survival was 46.8 +/- 9.9% after 9 years and 63.6 +/- 7.2% at 5 years. Postoperative calcitonin value is significant predictor of survival/Spearman's coefficient (R = 0.7048)/, worse prognosis is in correlation with high postoperative calcitonin values. The treatment of choice is at least total thyroidectomy and central lymph nodes resection if enlarged lymph nodes are found. Precise operative technique lowers the risk of postoperative complications. Complex approach to the patient with MTC includes all available methods in pre and postoperative evaluation as well as surgeon's knowledge and skill.

The diagnosis and medical management of advanced neuroendocrine tumors

Neuroendocrine tumors (NETs) constitute a heterogeneous group of neoplasms that originate from endocrine glands such as the pituitary, the parathyroids, and the (neuroendocrine) adrenal, as well as endocrine islets within glandular tissue (thyroid or pancreatic) and cells dispersed between exocrine cells, such as endocrine cells of the digestive (gastroenteropancreatic) and respiratory tracts. Conventionally, NETs may present with a wide variety of functional or nonfunctional endocrine syndromes and may be familial and have other associated tumors. Assessment of specific or general tumor markers offers high sensitivity in establishing the diagnosis and can also have prognostic significance. Imaging modalities include endoscopic ultrasonography, computed tomography and magnetic resonance imaging, and particularly, scintigraphy with somatostatin analogs and metaiodobenzylguanidine. Successful treatment of disseminated NETs requires a multimodal approach; radical tumor surgery may be curative but is rarely possible. Well-differentiated and slow-growing gastroenteropancreatic tumors should be treated with somatostatin analogs or alpha-interferon, with chemotherapy being reserved for poorly differentiated and progressive tumors. Therapy with radionuclides may be used for tumors exhibiting uptake to a diagnostic scan, either after surgery to eradicate microscopic residual disease or later if conventional treatment or biotherapy fails. Maintenance of the quality of life should be a priority, particularly because patients with disseminated disease may experience prolonged survival.

BRAF T1796A transversion mutation in various thyroid neoplasms

A high prevalence of activating mutation of the B type Raf kinase (BRAF) gene was recently reported in papillary thyroid cancer (PTC). However, the frequency of this mutation in several other types of thyroid neoplasms was not thoroughly investigated. In the present study, in addition to PTC, we evaluated various thyroid tumor types for the most common BRAF T1796A mutation by direct genomic DNA sequencing. We found a high and similar frequency (45%) of the BRAF T1796A mutation in two geographically distinct PTC patient populations: one composed of sporadic cases from North America, and the other from Kiev, Ukraine, that included individuals who were exposed to the Chernobyl nuclear accident. In contrast, we found BRAF mutation in only 20% of anaplastic thyroid cancers and no mutation in medullary thyroid cancers and benign thyroid hyperplasia. We also confirmed previous reports that the BRAF T1796A mutation did not occur in benign thyroid adenomas and follicular thyroid cancers. Specific analysis of the Ukraine patients with confirmed history of radiation exposure failed to show a higher incidence of BRAF mutation. Our results suggest that frequent occurrence of BRAF mutation is inherently associated with PTC, irrespective of geographic origin, and is apparently not a radiation-susceptible mutation. The lack or low prevalence of BRAF mutation in other thyroid neoplasms is consistent with the notion that other previously defined genetic alterations on the same signaling pathway are sufficient to cause tumorigenesis in most thyroid neoplasms.