Prognostic Significance of Disseminated Tumor Cells in the Connective Tissue of Patients with Medullary Thyroid Carcinoma

Persistent Hypercalcitoninemia in Patients with Medullary Thyroid Cancer

Medullary thyroid carcinoma is a highly malignant and progressive disease. Surgery is the only effective treatment. Calcitonin is a significant marker for medullary thyroid carcinoma, and due to its sensitivity it represents a useful tool for the follow-up. The outcome of patients affected by medullary thyroid carcinoma depends on tumor size, lymph node involvement, and adequacy of primary surgical management. In the present study, the authors reviewed their own experience in the cure of medullary thyroid carcinoma. Forty-one patients operated for sporadic medullary thyroid carcinoma were included. Indications for surgery, inclusive of lymphectomy techniques, timing of redo surgery, and the meaning of calcitonin levels in highlighting disease are extensively discussed. Patients with elevated calcitonin levels and favorable outcome are considered, together with the various diagnostic tools to be employed during patient workup.

[Total thyroidectomy with lymph node dissection of the central compartment for node-positive, capsular invasive papillary thyroid cancer: video contribution]

The aim of radical oncological surgery for nodal metastasized papillary thyroid cancer is, as for other oncological interventions in visceral surgery, the anatomy-related implementation of the concept of en bloc (no touch) resection of the organ bearing the primary tumor together with the first lymph node station, while the structures of the aerodigestive tract, the recurrent laryngeal nerves and parathyroid glands are preserved. The surgical technique is demonstrated in detail with the help of a video of the operation and which is available on-line, the advantages and disadvantages of the technique are discussed.

[Hereditary thyroid cancer]

Hereditary thyroid carcinomas are present in about 5% of differentiated (DTC) and 25% of medullary thyroid carcinomas (MTC). They are part of a multiorgan tumour syndrome (e. g. FAP Gardner's syndrome with DTC and MEN 2 syndrome with MTC) or confined to the thyroid gland. Hereditary thyroid carcinomas typically show multifocal growth and occur in young patients. Due to germ cell mutations as the underlying cause of disease, partial thyroidectomies that may be justified in early sporadic carcinomas are not indicated in this type of tumours. In the case of hereditary DTC, the genetic basis of the disease has been demonstrated only in syndromatic tumour variants. In most nonsyndromatic cases, specific genetic alterations have not yet been identified. In both types of hereditary DTC, prophylactic thyroidectomy is not warranted due to the favourable prognosis of tumours that do not differ from sporadic ones. Point mutations of the RET proto-oncogene have been known for 15 years to be the genetic basis of hereditary MTC. Recently several new mutations were discovered; however, final conclusions regarding their clinical significance are not possible at present. Basically it has been shown that the clinical aggressivity of tumour development follows a genotype-phenotype correlation (risk groups 1-3). However, in mutations of all risk classes there exists a wide spectrum of different stages of hereditary C-cell disease in individual risk groups. Regarding time and extent of prophylactic thyroidectomy (without or with lymph node dissection) a combined molecular-biochemical concept including the use of pentagastrin-stimulated calcitonin values is therefore recommended.