A Case of Papillary Thyroid Carcinoma in a Patient with Prader-Willi Syndrome

Abstract

The patient was a 38-year-old woman who had been diagnosed with Prader-Willi syndrome (PWS) in infancy. A screening ultrasonography showed a nodular lesion in the right lobe of the thyroid gland, and the patient was referred to our department for further examination and treatment. As a result of a thorough examination, its lesion was strongly suspected to be malignant, and we decided to perform surgery. Because of a delay in mental development, the patient sometimes became agitated, and it was difficult to induce general anesthesia. The patient underwent surgery to remove the right lobe and isthmus of the thyroid gland, followed by additional cervical lymph node dissection due to the diagnosis of papillary thyroid cancer by intraoperative diagnosis. Preoperative CT scan showed no enlarged cervical lymph nodes, but nine microscopic metastatic lymph nodes were found. As of two years and nine months after the surgery, no apparent recurrence has been observed. There are very few reports of malignant neoplasms in PWS patients, and this is the first report of papillary thyroid carcinoma with PWS in Japan.