Endocrine Abstracts

Pituitary tumors are the most frequent intracranial neoplasm, affecting 11 000 of the world wide population. However metastases in this location are rare and uncommon presentation of systemic malignancy. Although diabetes insipidus secondary to cancer metastasis to the pituitary gland is a common manifestation, anterior pituitary failure is rare. We present a −57-year-old man with hypopituitarism secondary to pituatry metastasis from lung cancer.

Case report: A 57-year-old patient active smoker presented with headache of 1 month. Cranial MRI revealed multiple subcortical lesions and hypophyseal noduler lesion 13.6 mm in diameter. The computary tomography scan of the Chest, Abdomen and Pelvis revealed a 23×22 mm rregularly margined mass in mass in the upper left lobe with mediastinal lymph nodes, liver and right adrenal metastases. Assessment of pituitary function revealed panhypopituitarism; Cortisol: 3.17 μg/dl, ACTH:11.5 pg/ml free T₄ 0.64 ng/dl (normal range 0–97–1.65), thyroid stimulating hormone level of 0.005 mUI/ml (normal range 0.5–4 IU/ml), total testosterone level of 0.025 ng/ml (normal range 2.5–10 ng/ml), follicle stimulating hormone level of 0.5 IU/ml (normal range 1–8.4 IU/ml), luteinizing hormon level of 0.1I U/l (normal range 1–10.5 IU/l) and normal urine osmolarity. Complete blood count showed the following: hemoglobin 13.6 g/dl, white cell count 12.64 K/ul, and platelet count 322 K/ul Evaluation of serum chemistry revealed lactate dehydrogenase 245 IU/l, sodium 129 mmol/l potassium 4.3 mmol/l. A hormone replacement therapy was indicated urgently. Fiberoptic bronchoscopy did not show any endobronchial lesion. Histopathologic examination of brochoalveolar lavage revealed metastasis of lung adenocarcinoma.

Conclusion: Despite the fact that pituitary metastasis are rare, they must be evaluated in the presence of pituitary involvement. It may be difficult to differentiate symptoms due to panhypopituitarism from the constitutional symptoms caused by cancer progression. Considering that the life expectancy is limited for advanced lung cancer patients, detection and appropriate treatment of hormonal insufficiency are important to improve their quality of life.