Association of melanoma with glioblastoma multiforme

Abstract

2082 Background: There are few well-established risk factors for the development of primary brain tumors. We conducted a descriptive, retrospective chart review, with the goal of identifying other systemic malignancies, including melanomas, which develop in adult patients with glioblastoma multiforme (GBM). We hypothesized an increased association of melanomas with GBM based on anecdotal observations. Methods: We queried the Johns Hopkins Cancer Registry to create a database of all patients with pathologically confirmed GBM diagnosed or treated at Johns Hopkins Hospital from June 1, 2000 to June 1, 2007. We performed a comprehensive review of the electronic medical record of these patients to describe personal history of prior or concomitant cancers, excluding non-melanomatous skin cancers. Multiple diagnoses in a single individual were recorded independently. We excluded individuals less than 18 years of age and those people with missing cancer history. We compared these data to historical controls based on publicly available Surveillance, Epidemiology, and End Results (SEER 17) data. Results: 510 records were assessed, with 12 excluded because of age less than 18, and 43 excluded because of absence of cancer history. From the remaining 455 individuals, representing 290 men and 165 women, we described 53 cancer diagnoses. Only 5 individuals contributed more than one cancer to this total number. The most commonly represented prior or concomitant malignancies were breast (n=6), melanoma (7), colorectal (8), and prostate (12). Expected counts for these cancers, based on SEER complete prevalence statistics, are respectively 5, 1, 2, and 6. Conclusions: In this preliminary retrospective analysis of a large GBM population, melanomas appear over-represented disproportionate to breast or prostate cancer. There has been previous suggestion of a possible association between gastrointestinal cancers and primary brain tumors, as in Turcot's syndrome. As melanomas and gliomas share common potential pathophysiologic pathways and responsiveness to temozolomide, these results may provoke further analysis to characterize a population at higher risk for development of these aggressive malignancies. No significant financial relationships to disclose.