Ectopic calcitonin secretion in a woman with large cell neuroendocrine lung carcinoma

OBJECTIVE: Serum calcitonin (CT) is a sensitive but not specific marker for medullary thyroid carcinoma (MTC). There are a large number of conditions that may elevate CT levels. CASE REPORT: Herein we present the case of a 47-year old woman with Hashimoto thyroiditis, goiter, cervical lymphadenopathy and high CT and CEA levels. After surgical extirpation of the lymph node neuroendocrine cancer metastasis was suspected. Computed tomography of the chest showed a tumor mass on the right lung. Bronchoscopy was performed and pathological and immunohistochemical analysis revealed large cell neuroendocrine lung cancer (LCNEC). After chemotherapy, significant reduction of tumor mass was achieved with a moderate decrease in CT levels in parallel. CONCLUSIONS: We present a female with LCNEC, a condition which is usually observed in older men (7th decade) and is not associated with CT secretion. Hashimoto thyroiditis is associated with increased incidence of different types of cancers (e.g. thyroid, colon). No reports at present exist on the incidence of lung cancers in patients with thyroid disease.