Faculty Bibliography

BACKGROUND AND PURPOSE/OBJECTIVE:ADC histogram analysis can stratify outcomes in patients with GBM treated with bevacizumab. Therefore, we compared gene expression between high-versus-low ADC tumors to identify gene expression modules that could underlie this difference and impact patient prognosis. MATERIALS AND METHODS/METHODS:Up-front bevacizumab-treated patients (N = 38) with newly diagnosed glioblastoma were analyzed by using an ADC histogram approach based on enhancing tumor. Using microarrays, we compared gene expression in high-versus-low ADC tumors in patients subsequently treated with bevacizumab. Tissue sections from a subset of tumors were stained for collagen and collagen-binding proteins. Progression-free and overall survival was determined by using Cox proportional hazard ratios and the Kaplan-Meier method with the log rank test. RESULTS:A total of 13 genes were expressed at 2-fold or greater levels in high- compared with low-ADC tumors at the P < .05 level. Of these, 6 encode for collagen or collagen-binding proteins. High gene expression for the collagen-binding protein decorin was associated with shorter survival (HR, 2.5; P = .03). The pattern and degree of collagen staining were highly variable in both high- and low-ADC tumors. CONCLUSIONS:High-ADC GBMs show greater levels of ECM protein gene expression compared with low-ADC GBMs. It is unclear whether this translates to the accumulation of higher levels of the encoded proteins. However, because ECM molecules could contribute to a proinvasive phenotype, this relationship merits further investigation.

OBJECTIVE:To discuss the role of bilateral adrenalectomy in Cushing syndrome, as illustrated in a case of severe hypercortisolism that was unresponsive to combination agent medical therapy. METHODS:We report the clinical, laboratory, imaging, and pathologic findings in a patient with ectopic Cushing syndrome attributable to an adrenocorticotropic hormone (ACTH)-secreting neuroblastoma. In addition, we provide a literature review regarding olfactory neuroblastoma and discuss current and emerging therapeutic options for Cushing syndrome. RESULTS:A 59-year-old man presented with nasal congestion and neck swelling and was noted to have hypokalemia, hypertension, and hyperglycemia. A nasal biopsy demonstrated a poorly differentiated carcinoma with neuroendocrine features. He was subsequently diagnosed as having ACTH-dependent Cushing syndrome, but despite high-dose combination medical therapy, his condition rapidly deteriorated. Urgent bilateral adrenalectomy provided rapid control of the hypercortisolism, and the patient was later able to undergo an uncomplicated total macroscopic resection of his locally metastatic primary tumor. CONCLUSION/CONCLUSIONS:This report describes the challenges in the diagnosis and management of ACTH-dependent Cushing syndrome and highlights the important role that bilateral adrenalectomy can still have in patients with severe hypercortisolism causing life-threatening complications.