ABSTRACT
OBJECTIVE: We report a case of pituitary metastasis (PM) presenting with acute anterior and posterior pituitary dysfunction following a two-decade-long oncologic course marked by disease progression. CASE REPORT: An elderly woman with a history of stage IIA invasive ductal carcinoma of the breast presented with confusion. Her laboratory evaluation was significant for panhypopituitarism and central diabetes insipidus, and magnetic resonance imaging findings were suggestive of PM. She was treated with hormone replacement, resulting in the reversal of her metabolic and cognitive derangements. DISCUSSION: PM is a rare complication of advanced malignancy. Although several malignancies may spread to the pituitary, the most common are breast cancer in women and lung cancer in men. Unlike pituitary adenomas, which predominantly involve the anterior pituitary, PM has a predilection for the posterior lobe and infundibulum due to direct access via systemic circulation. The clinical presentation of PM depends on the size of the metastatic deposit and other structures involved in the vicinity of the sella. Magnetic resonance imaging with gadolinium is the gold standard for the evaluation of sellar masses. The diagnosis of PM involves a thorough history, physical examination, biochemical evaluation of the hypothalamic-pituitary axis, and imaging studies. CONCLUSION: Metastatic involvement of the pituitary is a rare condition seen in <2% of resected pituitary masses. The clinical presentation is heterogeneous and can include headache, visual impairment, and panhypopituitarism. Unfortunately, the presence of PM portends a poor prognosis, and the median survival rate after diagnosis is 6 to 13.6 months.
ABSTRACT
OBJECTIVES/HYPOTHESIS: Excitotoxic and related inflammatory injury are implicated in the spiral ganglion degeneration seen with Meniere's disease and endolymphatic hydrops (ELH). Excitotoxicity is initiated with glutamate elevation and associated with downstream increases in reactive oxygen species resulting in inflammation-mediated neuronal degeneration. This study tests the hypothesis that interruption of the initial and/or downstream aspects of excitotoxicity should provide hearing protection in ELH-associated hearing loss. STUDY DESIGN: This study tests whether riluzole, a glutamate release inhibitor, and dimethylsulfoxide (DMSO), an anti-inflammatory and antioxidant solvent with favorable properties at the level of glutamate receptors, can protect against early-stage hearing loss in a mouse model of ELH. METHODS: The Phex(Hyp-Duk) mouse spontaneously develops ELH and postnatal hearing loss. Starting at postnatal day 6 (P6), daily injections of riluzole + DMSO or just DMSO were administered. Untreated mutants served as controls. At P21, P25, and P30, hearing function was assessed by recording auditory brainstem responses. A cochlear function index was developed to assess global cochlear function at each time point. RESULTS: Compared to no treatment, DMSO provided significant hearing protection (P < .05). The riluzole + DMSO also showed protection, but it was statistically indistinguishable from DMSO alone; a synergistic increase in protection with riluzole was not observed. CONCLUSIONS: This study demonstrates pharmacological hearing protection in an animal model of ELH. The results support the assertion that inflammatory (reactive oxygen species) injury, which is part of the excitotoxic pathway, contributes to the development of ELH-associated hearing loss.
