Background: Medullary Thyroid Carcinoma (MTC) originates from the thyroid C cells and accounts for approximately 5-9% of all thyroid cancers. Aim of this study was to retrospectively evaluate the outcomes of 41 patients with MTC who underwent treatment at our institution. PATIENTS AND METHODS. We reviewed the records of 41 patients who underwent surgery between 1995 and 2004. The patients were divided into two groups: A) patients (n 30) without any previous surgery. B) patients (n 11) previously thyroidectomized and high calcitonin levels with or without radiological evidence of local regional or distant metastases. We performed total thyroidectomy with central compartment lymphadenectomy and ipsilateral modified radical neck dissection in group A patients. Group B patients underwent re-excision of the central neck compartment and bilateral modified radical neck dissection if it had not been previously performed.
Results: Most patients had major reduction in postoperative calcitonin levels. Compartmental dissection of the cervical node significantly improved the results of primary surgery and calcitonin returned to normal levels in approximately 60% of the patients in group A, but only the 30% of the patients in group B.
Conclusions: The extent of the primary surgical resection and the evidence of local or distant metastases significantly influence the outcome of MTC patients. An extensive lymphadenectomy performed early in the treatment and re-operative cervical lymphadenectomy in patients with persistently high calcitonin levels after thyroidectomy significantly improved the outcome, although re-operation rarely results in normalized calcitonin levels and is associated with a higher incidence of complications.