Heterotopic Ossification (HO) in Caecal Adenocarcinoma: A Case Report

The Heterotopic Ossification (HO) or Osseous Metaplasia (OM), is a rare condition that presents as benign bone formation at nonskeletal locations, often incidentally identified during histopathological evaluation but not typically radiologically detected. HO within colorectal adenocarcinoma occurs rarely; only a few cases have been reported in the literature, which demonstrate how unique cases expand our knowledge of this unusual entity and its diagnostic implications. Author presents a case of a 47-yearold female patient who had a history of three months of abdominal pain with a 5 kg weight loss over the past month. She was found to have a 3×3 cm hard immobile mass in the right iliac fossa on physical examination, which CT imaging showed to be an irregular circumferential thickening with a malignant-appearance involving the caecum, terminal ileum, lower ascending colon and proximal appendix. Interestingly, there was no sign of ossification on CT scan. A right hemicolectomy was done and the resected specimen was sent for histopathological examination. Histology confirmed an infiltrative malignant neoplasm consistent with a moderately differentiated adenocarcinoma. Importantly, benign bone tissue was seen within the fibrous stroma of the tumour. In this case, we emphasise the significance of histopathological evaluation for correct diagnosis when primary ossifying softtissue neoplasms or carcinosarcomas are suspected because these have a worse prognosis than HO. Although HO in colorectal carcinoma is rare, it does not appear to directly affect the patient’s prognosis; however, further study of this entity is crucial as cases continue to increase.