<prompt> Attacks of flushing and cyanosis occur in which type of ovarian tumors:Struma ovariiKrukenbergs tumorArrhenoblastomaCarcinoid tumors of ovary  <response>: Carcinoid tumour of Ovary: It is sometimes primary and sometimes metastatic. Also called Argentaffinoma. Occurs as a malignant change in benign dermoid cyst. Presence of solid yellow tumour with histological property of reducing silver salts derived from specialized Kulchitsky cells of intestine. It produced 5 - HT which causes attacks of flushing and cyanosis. 