Carcinoma tímico intratiroideo diagnosticado erróneamente como carcinoma medular de tiroides

Abstract

The intrathyroidal thymic carcinoma is a rare neoplasm. The probable origin of this neoplasm is the presence of ectopic thymic tissue or remnants of the third and fourth branchial arch. The case of a 49-year-old female with an initial diagnosis of medullary thyroid cancer is presented. When she was operated for regional recurrence, 16 years later, the pathology report demonstrates the presence of a intrathyroidal thymic carcinoma. Intrathyroidal thymic carcinoma is considered an independent type of thyroid carcinoma because this entity has specific clinical-pathological characteristics similar to thymic carcinomas and different prognosis than known thyroid carcinomas. We present the case of a patient initially treated as having a medullary thyroid carcinoma who, upon presenting recurrence, the presence of intrathyroidal thymic carcinoma was demonstrated.

Case report: Thymoid differentiated carcinoma of thyroid: Two cases

“…At present, it is believed that CASTLE may be derived from ectopic thymus or gill sac residual tissue, which usually has an insidious onset and is mostly found in the form of neck mass, and can also be seen for treatment in the form of hoarseness and dyspnea ( 3 , 4 ). Preoperative imaging and cytological diagnosis of this disease are difficult, and it is easy to be confused with thyroid squamous cell carcinoma, poorly differentiated or undifferentiated thyroid carcinoma, thyroid metastatic lymphoepitheliomatoid carcinoma, metastatic squamous cell carcinoma, and thymic carcinoma ( 5 , 6 ). Most literature studies show that CASTLE has a slow course of disease and a good prognosis.…”