| Summary: | The term "cancer of unknown primary" refers to a condition in which a patient has metastatic malignancy without an identified primary source. This is a very heterogeneous disease in which the type of tumour, the extent of spread, and the outcome of treatment all vary widely. When categorising patients with cancer of unknown primary, one important factor initially considered is the cell type of origin of the metastatic disease. The majority of patients have malignancy which appears to derive from epithelial cells, and hence are regarded as having carcinoma of unknown primary. Patients with tumours of non-epithelial lineage (melanoma, sarcoma, lymphoma, germ-cell) form a distinct and important minority, since subsequent management can often be satisfactorily undertaken even in the absence of an identifiable primary source. Such patients are not considered in this guideline, since their care is adequately defined in existing guidelines for their specific tumour type. The term "carcinoma of unknown primary" (CUP) is used henceforth to refer to those patients with metastatic malignancy of epithelial, neuroendocrine or undifferentiated lineage whose investigation and management is considered within the scope of this guideline
|
|---|