Clinical characteristics of hereditary and sporadic medullary thyroid carcinoma

To study the clinical characteristics and outcomes of the hereditary medullary thyroid carcinoma (HMTC) and the sporadic medullary thyroid carcinoma (SMTC).

The clinical data of 78 patients with medullary thyroid carcinoma who underwent surgery in our hospital between July 1980 and May 2011 were retrospectively analyzed.

Of these 78 patients, there were 23 HMTC cases and 55 SMTC cases. The HMTC group was significantly younger age of onset [(36.4±13.5) years vs. (46.6±11.2) years, P<0.01] and a lower pre/post-operative serum calcitonin levels [(850.4±110.20) ng/L vs. (1450.4±118.3) ng/L, P<0.01 and (410.8±133.2) ng/L vs. (1585.4±129.5) ng/L, P<0.01] than the SMTC group. In addition, the mean tumor diameter was also significantly smaller in the HMTC group (14.3 mm vs. 21.0 mm in SMTC group, P<0.05). Tumor multifocality was seen in a significantly higher proportion of HMTC cases compared with the SMTC cases (56.6% vs. 29.1%, P<0.05). The overall 10-year survival was 100% in HMTC group and 80.2% in SMTC group (P<0.05).

HMTC has a better prognosis than SMTC.