Endocrine Abstracts

Second malignant neoplasm following irradiation is a rare sequelae of primary childhood malignancies. Irradiation is a well-known risk factor for the development of benign and malignant thyroid tumors. Here we present the case of a young woman with medulloblastoma, who later developed thyroid cancer and eventually was also diagnosed with a cholangiocarcinoma.

At the age of 7 the patient presented with headaches, nausea, vomiting, fatigue, somnolence and double vision and was diagnosed with a posterior scala tumor. She underwent suboccipital craniotomy with macroscopic complete removal of the tumor. Pathology confirmed medulloblastoma. This was followed by chemotherapy with intrathecal methotrexate. After chemotherapy she received complete craniospinal irradiation (36 Gy + 20 Gy boost). Oncologic follow up did not reveal recurrence of medulloblastoma. Endocrinologic workup revealed GH deficiency, but no other pituitary hormone deficiency. GH therapy was not recommended since her history of malignant tumor. At the age of 15 she presented with neck lymphadenopathy and was found to have papillary thyroid cancer. She underwent total thyroidectomy and radioiodine therapy in 4 sessions with a cumulative dose of 800 MBq. Regular endocrinologic follow up with tumor markers and imaging did not reveal evidence of thyroid carcinoma recurrence. At the age of 27 she became pregnant. Her early pregnancy was complicated by gestational diabetes as well as an ovarian cyst, for which she underwent exploration laparotomy and left adnexectomy while 23 weeks pregnant. In the 37th week of her pregnancy during a routine endocrinology appointment she was found to have icterus, therefore urgent C-section was recommended. Since the icterus did not resolve after the delivery she had an ERCP and a biliary stent was placed. MRCP showed an intrahepatic tumor. Initial biopsy showed adenocarcinoma with an unknown pancreatic vs gastric vs biliary source. She had a percutan transhepatic drain placed. Subsequent exploratory laparotomy showed peritoneal carcinosis and biopsy revealed cholangiocarcinoma. Due to the extent of her disease surgical treatment was not possible, but palliative chemotherapy was planned. This had to be postponed due to bilateral pulmonary emboli. In the interim her disease has further progressed and she unfortunately passed away before she could have started her treatment.

While having thyroid cancer after irradiation for medulloblastoma could be accounted for the irradiation itself, the development of this patient’s third tumor raises the possibility of a genetic abnormality leading to development of multiple tumors. We are currently conducting genetic testing to further investigate this possibility.