The retrospective study of 33 patients with medullary thyroid carcinoma (MCT) after primary surgical therapy is presented. In the course of ten years 4 patients with hereditary form of MCT (12.1%) were operated and 29 patients (87.9%) sporadic MCT with were treated. Mixed (diferenciated and medullary) carcinoma was found in three cases (9.9%). Pacients with histopatologic classification pT3N0M0, pT2pN1aM0 or worse were indicated to adjuvant postoperative external radiotherapy. As complications of surgical therapy there were identified unilateral recurrens nerve damage in 2 cases (6.6%). Lasting postoperative hypocalcemia was determinated in 3 cases (9,9%), Horner’s syndrome and postoperative lymphorrhea were observed each in one case (3.3%). We saw the most early manifestating distant metastasis 5 months after the operation of patient with MCT pT3pN1aM0. On the other side, no locoregional persistent disease and no lymphatic metastasis of MCT were identified after surgical therapy of patients with pT1N0M0. Only 2 patients (6.6%) with primary advanced disease died 8 and 11 years after operation. The authors discuss first of all an advance of primary surgical therapy at 33 patients. The review of contemporary opinions is adduced. More extensive surgical intervention is recommended for hereditary forms of MCT. If there is a suspicion of micrometastasis in prelaryngeal et pretracheal region, applying of central neck dissection is necessary according to a biological character of this disease. The extent of primary tumor, the attendance of nodal nad distant metastasis, high basal and stimulating level of imunocalcitonin (iCT) and hereditary form of MCT – there are defined as main negative prognostic factors for MCT. Finally, the suggestion of primary surgical therapeutic extension is recommended, according to TMN classification and clinical form of MCT disease.

        Key words: medullary carcinoma, surgical treatment, neck dissection, negative prognostic factor, complications of surgical treatment.