What is the term used for cancer of unknown primary?

The term "occult tumor" refers specifically to cancer that is present in the body but for which the originating site or primary tumor cannot be identified through examinations, imaging studies, or biopsies. This phenomenon often occurs when the cancer has already spread to other parts of the body (metastasized), making it challenging to trace back to its original source.

Understanding "occult tumor" is crucial in oncology because it guides the treatment approach and helps healthcare providers determine the most effective management strategies for the patient. By recognizing that the primary site is unknown, oncologists may opt for broad-spectrum treatments that target multiple potential tumor types rather than focusing therapies only available for a confirmed primary site.

In contrast, metastatic carcinoma refers to malignancies that have spread from a known primary site to other parts of the body, while primary carcinoma would indicate cancer that is localized to its original site. Subclinical cancer, on the other hand, refers to a stage of cancer that is not detectable by symptoms or standard diagnostic tests. Thus, these terms serve different purposes in oncology, with "occult tumor" being the most accurately described term for cancers of unknown origin.