A Clinical Study of Medullary Thyroid Carcinoma: 12 Cases

Lee, Jang Han; Shim, Yoon Sang; Lee, Yong Sik; Lee, Guk Haeng; Park, Sang Jun; Park, Seok Jin

Abstract

BACKGROUND AND OBJECTIVES: Medullary thyroid carcinoma (MTC) accounts for about 5-10% of all thyroid cancers worldwide, but only for 2-4% in Korea. Its prognosis is relatively poorer than well-differentiated thyroid carcinoma (WDTC). We performed this study to find the adequate treatment methods through the analysis of clinical features and treatment process of 12 MTC cases.
MATERIALS AND METHODS
We conducted retrospective chart review about 12 cases of pathologically proven MTC treated from 1991 to 1996 at the department of Otolaryngology-Head and Neck Surgery, Korea Cancer Center Hospital. We analyzed their clinical features, treatment modalities and treatment outcomes.
RESULTS
Male/female ratio was 1:1 (6:6) with the mean age of 46.2 (19-73) years. Mean follow-up periods were 26.8 (3-48) months and MTC accounted for 2.7% of all thyroid cancers during the period of 1991 to 1996. We performed surgical procedures in all cases. In 5 cases of disease-free status, complete surgical removal of tumor was performed in the first operation, and no recurrence occurred during the follow-up period. In the other 5 cases, incomplete surgical removal was inevitable due to carotid artery invasion or mediastinal extension, etc. These patients received many additional surgery and radiotherapy, but their condtion did not improve. In one case, we performed complete excision but he expired with double primary cancer: one other case who was confirmed as MEN type 2b had been suspicious of recurrence, but she was lost during the follow-up period.
CONCLUSION
We confirmed that MTC has relatively poorer prognosis than WDTC, and completeness of surgical excision is important. Persistent tumor is a major cause of mortality, and the tumor is unable to remove through the other methods. So early diagnosis and treatment is the most important prognostic factor. We recommend that aggressive and meticulous surgical removal is important in MTC management.