Synchronous osteosarcoma of the bladder and adenocarcinoma of the colon: A case report

Abstract

Introduction: Extraosseous osteosarcomas are rare mesenchymal tumors. Primary osteosarcomas may arise from parenchymal organs like bladder, liver and heart. The number of cases with osteosarcoma primarily arising from the bladder found to be less than 35 in a literature review. We describe the second patient reported in the English literature with primary bladder osteosarcoma and colon adenocarcinoma. Case report: An 83-year-old male patient presented with complaints of abdominal pain, hematuria, constipation, and weight loss. Computed tomography of the abdomen and pelvis demonstrated a heterogeneous giant mass with lobulated contour measuring 5x3.5 cm at the level of the right ureter orifice in the bladder lumen. The transurethral bladder biopsy showed pleomorphic tumor cells with hyperchromatic nuclei, localized between eosinophilic homogeneous osteoids and fibroblastic malignant cells producing lace-like osteoid matrix. A polyp measuring 2 cm in diameter detected in the colon in the colonoscopy performed for preoperative evaluation. Adenocarcinoma reported as the result of biopsy. Cystectomy and left hemicholectomy in the same session decided. However, the patient refused all surgical and medical interventions. The patient died due to uropsepsis 8 months after initial diagnosis. Conclusion: Osteosarcoma of the bladder is a rare tumor with a very poor prognosis. The differential diagnosis gains a significant degree of importance. It would be beneficial to investigate cases like this with regard to synchronous colon and bladder tumors.