ck 7 negative and ck 20 negative tumor is?

Ans is 'a' i.e. Prostate carcinoma o Cytokeratin 7 (CK 7) and cytokeratin 20 (CK 20) are low molecular weight cytokeratins. Their anatomic distribution is generally restricted to epithelia and their neoplasms.Cytokeratin immunohistologyTumors/oragnsCK7+ / CK20+carcinomas of .bile duct (extrahepatic / gallbladder), mucinous bronchioloalveolar carcinoma of lung, pancreas carcinoma, urothelium carcinoma, primary mucinous tumors of ovary, upper GI tract and endocervix.CK7+/CK20-carcinomas of bile duct (intrahepatic), breast, endocervical and endometrial adenocarcinoma, esophagus (distal), lung (not mucinous bronchioloalveolar), salivary gland, thyroid, mesotheliomaCK7- / CK20+carcinoma of colon (particularly early stage), primary mucinous tumors of lower GI tract, GI stromal tumor (Krukenberg), primary bladder adenocarcinoma.CK7-/CK20-carcinoma of adrenal cortex, prostate