Cancer Of Unknown Primary (CUP)

CUP involves advanced adenocarcinoma, squamous cell, or poorly differentiated carcinomas spreading to lymph nodes, liver, lungs, or bones; it affects adults over 60 equally across genders, with poorer prognosis than known primaries due to heterogeneity. Molecular profiling reveals hidden origins in 20-30% cases.?

Symptoms and Diagnosis

Signs mirror metastases: unexplained weight loss, fatigue, pain (bone/abdomen), cough, lumps, jaundice, or ascites; diagnosis requires biopsy, IHC (CK7/20, TTF-1), CT/PET scans, and NGS to classify favorable (e.g., women with axillary nodes) vs. unfavorable subsets.?

Treatment Approaches

Empiric platinum-based chemotherapy (taxane/gemcitabine) yields 20-30% response; site-specific therapy if origin inferred (e.g., taxanes for breast-like); immunotherapy suits MSI-high/PD-L1+ cases, with median survival 6-12 months. Clinical trials test precision medicine.