[Carcinoma with unknown primary site: Morphological diagnosis]

Carcinoma with unknown primary site (CUPs) is a group of malignant tumors, the first manifestation of which is metastatic dissemination. A primary tumor cannot be usually identified by a physical examination of patients with CUPs; a postmortem study plays a significant role in the diagnosis of the origin of metastasis. The paper gives the data available in the literature data on the postmortem diagnosis of CUPs and considers the morphological characteristics of metastases and the possibilities of immunohistochemical diagnosis and a molecular genetic method in the search for a primary focus.