Osseous Metaplasia in Rectal and Appendicular Carcinoma: A Diagnostic Dilemma?
Heterotopic bone formation also known as osseous metaplasia is an uncommon finding in benign and malignant gastrointestinal tumors. It has been described in adenocarcinoma lung, carcinoma breast, thyroid, parotid and pancreas. The overall incidence is approximately 0.4% as suggested by Dukes. We present two cases of rectal and appendicular mucinous adenocarcinoma with osseous metaplasia.