Choice of the Optimal Volume of Surgery for Patients with Sporadic Medullary Thyroid Cancer

Abstract

ABSTRACTObjectivesInfluence of lymphatic metastases at immediate and follow-up results of patients’ surgical treatment is controversial, especially for sporadic medullary thyroid carcinoma (SMTC).MethodsA total of 3330 thyroid cancer patients were operated on (1973-2009), among them 226 (6.8%) were medullary thyroid cancer (MTC) patients. In 11 observations, MTC appeared as a part of MEN syndrome. Sporadic character of disease was confirmed in 215 (95.1%) cases. There were 140 (80.8%) females and 33 (19.2%) males (4.2:1.0) with average age 48.6 ± 2.7. Long-term results (1-40 yrs) were investigated in 173 (94.2%) cases. All SMTC patients were divided in to three groups. Group 1 made of 80 (46.2%) T1- 3N0M0, Group 2 of 47 (27.3%) T1-3N1a-bM0, Group 3 of 46 (26.6%) T4N1a-bM0 patients.ResultsGroup1: Organ-sparing operations were carried out in 59 (73.7%), thyroidectomies in 21 (26.3%) patients. Multicentric tumor growth (MTG) was observed in 19.1%: in T1 cases - 5.7%, T2 - 20.5%, T3 - 46.7%. All patients underwent ipsilateral prophylactic central neck dissection (CND). Average period of postoperative observation (APPO), 12.0 ± 1.7. 5 years survival rate made 98.4%, 10-91.7%. Local relapse of MTC was found in one patient (in contralateral thyroid lobe).Group 2: Organ-sparing operations were carried out in 20 (42.6%), thyroidectomies—27 (57.4%) with curative central or central and lateral lymphadenectomy (LAE). MTG took place in 47.2%. Six group metastases only (T1a) were found in 38.9% and CND was performed. In other cases (61.1%), CND, lateral and mediastinal (8.3%) LAE were performed. APPO correspondent to 10.8 + 2.1 years. Repeated LAE because lymphatic metastases were carry out in 15 (31.9%) patients through 7.2 ± 2.4 years in average after initial operations. Tumor relapses were not found in thyroid remnant. Five-year survival rate made 89.2%, 10-67.8%.Group 3: MTG was observed in 64.3%. Central compartment group lymphatic metastases were revealed in 93.3%, in 2 to 5 groups – 86.7%, in mediastinum – 38.5%, distant metastases – in 22.0%. Combined operations were performed in 58.9%, palliative in 45 (26.6 %) cases. Operations were completed by tracheostomy in 38.4%. Adjuvant therapy (X-ray, chemotherapy) was applied in 28.9%. Postoperative lethality made 6.5%. APPO corresponded to 3.3 ± 0.8 (1-10 yrs). During first year, eight patients have died. Five-year survival rate made 32.4%.ConclusionDetection of regional metastases of SMTC during the first patient presentation significantly worsen survival rate. Early diagnosis of SMTC by calcitonin level detection is the best way to improve results of treatment. Organ-sparing thyroidectomies with mandatory ipsilateral prophylactics CND are justified only at T1N0M0 sporadic MTC.