Metastatic carcinoma from a tumour of unknown origin is a frequent clinical problem and identification of the primary site of origin may represent a difficult challenge for the clinician. Although most patients with metastatic carcinoma of unknown primary site have an ominous prognosis, there are subgroups of patients who are eligible for specific therapy and it is therefore mandatory to exploit every effort in order to identify accurately the tumour origin. The pathologist has acquired an increasing role in the characterization of the site of origin of these tumours by utilizing immunohistochemistry and molecular biological techniques. Recently, new powerful markers like cytokeratin 7 and 20, thyroid transcription factor 1 and Hep-1 have become available for the identification of the primary site of metastatic tumours, widening our limited repertoire of site-specific tumour antibodies. With the appropriate utilization of a restricted panel of antibodies it is now frequently possible to determine the site of origin of a metastatic carcinoma, solving several difficult clinico-pathological problems. However, this is not the end of the story: we still need more site- and tumour-specific markers in order to increase our diagnostic accuracy further.
- Metastatic carcinoma
- Unknown primary site
ASJC Scopus subject areas
- Pathology and Forensic Medicine