5 MC is a variant of endocrine carcinoma and should be classified according to endocrine carcinoma of lung or gastrointestinal tract into well-differentiated or poorly differentiated endocrine carcinoma. MC is associated with hormone secretions and is responsible for causing hormonal manifestations. Therefore, in the next WHO classification it should be classified with other endocrine carcinomas for uniformity in diagnosis, prognostic and therapeutic purposes.