Sellar and Suprasellar Masses: Pituitary Metastasis As An Important Differential
Mina Mohammad Ebrahim, Christopher Gilfillan, Rosemary Wong
Department of Diabetes and Endocrinology, Eastern Health, Melbourne, Vic
Background: Although pituitary metastases (PM) constitute 1% of all intracranial metastases, the incidence is rising due to longer life expectancy in patients with malignancies.
Case report: We are presenting two cases of PM from Prostate cancer and non-small-cell lung (NSCL) cancer. Case 1. 88-year-old man presented with fall and diplopia. He had diplopia, right 3rd, 5th and 6th nerve palsy and visual field defect. The Brain MRI revealed a mass at the junction of the right orbit and ethmoid and also a large pituitary mass. Multiple pulmonary, nodal, skeletal metastases and a small nodule in the left lateral chest wall noted on CT chest. The chest wall biopsy confirmed a metastatic prostatic adenocarcinoma. He received whole brain radiotherapy, androgen deprivation therapy and cabergolin. On follow up, diplopia and visual field were resolved. Repeat MRI pituitary showed no change in pituitary tumour size. Case 2. 59-year-old smoker presented with cough, weight loss, headache, diplopia and blurred vision. The CT scan showed lung mass and multiple hepatic lesions which confirmed to be metastatic squamous cell lung cancer on biopsy. MRI Brain showed sellar and suprasellar mass with invasion to left cavernous sinus and compression of the optic chiasm. The tests showed Pan-hypopituitarism. He had transphenoidal biopsy of the sellar tumour which showed metastatic NSCL carcinoma. Post-operatively, he represented with Left 5th and 6th nerve palsy and diabetes insipidus (DI) in one week and treated with palliative chemo-radiotherapy.
Conclusions: PM is an important differential diagnosis in patients with a pituitary mass. DI and cranial neuropathies are highly predictive of PM. Indications for surgery include confirmation of metastatic disease, and to alleviate symptoms although surgery has no impact on survival.