Identifying Two Distinct Previously Undiagnosed Cancers Within a Single Osseous Lesion: A Diagnostic Dilemma

Abstract

A 71-year-old man presented with a distal femur lesion. Workup was positive for elevated prostate-specific antigen, serum protein electrophoresis, and urine protein electrophoresis. He underwent distal femoral resection, and histological evaluation was consistent with concomitant metastatic prostate cancer and multiple myeloma.