cancer of unknown primary; CUP
Medical term for metastatic cancer where the original tumor site cannot be identified.
I was diagnosed with cancer of unknown primary and underwent detailed tests.
Standard medical term using がん in kana; common in patient-facing materials.
Kanji form using 癌; often seen in formal medical documents.
Compound of 原発 (primary/origin), 不明 (unknown), and がん (cancer).