Synchronous occurrence of Retroperitoneal Pleomorphic Liposarcoma and Papillary thyroid carcinoma: A Rare Case Report

Introduction: Pleomorphic liposarcoma is one of the rarest malignancies. In this case report, we present a primary pleomorphic liposarcoma of the retroperitoneal cavity in a 73-year-old male patient. Case Presentation: Contrast-enhanced computed tomography revealed a giant mass in the right abdomen (retroperitoneal) with areas of fat attenuation, appearing to encase the right kidney and showing features of a retroperitoneal liposarcoma involving the right kidney. The patient subsequently underwent surgery, and the specimen sent for histopathological examination was confirmed as pleomorphic liposarcoma of the retroperitoneal cavity. Additionally, papillary thyroid carcinoma, which is usually seen in younger patients and rarely presents as part of synchronous malignancies, was noted in this case where the same patient presented with a swelling in the front of the neck. Fine needle aspiration cytology revealed it to be papillary thyroid carcinoma. Following surgery, histopathological examination of the specimen confirmed it as a papillary variant of thyroid carcinoma. Conclusion: This case report highlights the occurrence of rare synchronous malignancies of both epithelial and non-epithelial/sarcomatous origin. The concurrent presentation of papillary thyroid carcinoma with pleomorphic liposarcoma is particularly rare.