title: Thyroid neoplasia following irradiation for medulloblastoma: report of two cases.
abstract: Thyroid neoplasms occurred in two patients 14 and 18 years after treatment with radiation for medulloblastoma. One patient has a papillary cancer and the other patient had multiple adenomas and a Hurthle cell adenoma. In addition, the latter case had foci of hyperplasia plus a microfollicular transformation, which has not been described in association with prior thyroid irradiation. The radiation doses delivered to the thyroid through posterior cervical spinal ports (2000--3000 roentgens) fall within the upper range of radiation dosage associated with induction of neoplastic changes within the thyroid.
mesh_terms: D000236:Adenoma / Q000209:etiology / Q000473:pathology; D000328:Adult; D001932:Brain Neoplasms / Q000532:radiotherapy*; D002291:Carcinoma, Papillary / Q000209:etiology / Q000473:pathology; D002675:Child, Preschool; D005260:Female; D006801:Humans; D008527:Medulloblastoma / Q000532:radiotherapy*; D009378:Neoplasms, Multiple Primary / Q000209:etiology* / Q000473:pathology; D009381:Neoplasms, Radiation-Induced / Q000473:pathology; D011879:Radiotherapy Dosage; D013964:Thyroid Neoplasms / Q000209:etiology* / Q000473:pathology