Intrathyroidal Thymic Carcinoma Mimicking Anaplastic Thyroid Cancer: A Case Report

Intrathyroidal Thymic Carcinoma Mimicking Anaplastic Thyroid Cancer: A Case Report

Intrathyroidal thymic carcinoma (ITC) is an extremely rare malignant tumor that presents a diagnostic challenge owing to its similarity to anaplastic thyroid cancer and other aggressive thyroid malignancies. We present the case of a 79-year-old woman who was initially suspected of having anaplastic thyroid cancer; however, post-operative pathology revealed an ITC. The patient underwent a palliative surgical approach consisting of right total thyroidectomy and selective neck dissection, followed by adjuvant radiotherapy and chemotherapy. Treatment was successfully completed without complications or relapse. This case serves as a reminder to consider ITC as a differential diagnosis in patients presenting with atypical features resembling anaplastic thyroid cancer and to approach the treatment plan with careful consideration of the individual patient’s age, tumor characteristics, and prognosis.