What is the most likely underlying diagnosis in this 82-year-old patient with diabetes mellitus who had undergone a total hip replacement 10 years previously?
Answer A. Colon cancerThere is free air extending lateral to the greater trochanter. Intra-articular cultures grew Clostridium septicum, which has a known association with colorectal cancer. Subsequent colonoscopy revealed a fungating colonic adenocarcinoma.
Colon cancer
Hypogammaglobulinemia
Hypophosphatasia
Osteosarcoma
Endocrinology