A rare case of thyroid carcinosarcoma arising from recurrent papillary thyroid cancer: Case report and review of the literature

Background: Thyroid carcinosarcoma represents a rare subtype of thyroid cancer, distinguished by its unique histopathology-simultaneous malignant epithelial and mesenchymal cells. The occurrence of thyroid carcinosarcoma arising from recurrent papillary thyroid cancer is exceptionally infrequent. Methods: Study outlines a patient's thyroid carcinosarcoma journey, covering presentation, recurrence, diagnostics, surgeries, and follow-up. A PubMed search gathered data on pathological features and treatment approaches for thyroid carcinosarcoma. Results: The patient initially diagnosed with papillary thyroid cancer underwent thyroidectomy, neck dissection, and radioactive iodine therapy. Recurrence revealed thyroid carcinosarcoma, featuring papillary carcinoma, squamous cell carcinoma, and spindle cell components. Total laryngectomy followed by adjuvant radiotherapy and chemotherapy. The patient was followed for 17 months with no evidence of disease. Conclusions: This extraordinary case exemplifies a rare instance of local relapse in form of thyroid carcinosarcoma following an initial diagnosis of papillary thyroid carcinoma. Surgical resection and chemoradiotherapy show promising outcomes in managing this challenging condition.