Long-term toxicity of bevacizumab therapy in neurofibromatosis 2 patients.

PURPOSE: Bevacizumab treatment is associated with tumor shrinkage and hearing improvement in about 50 % of neurofibromatosis 2 (NF2) patients with progressive vestibular schwannomas. Hypertension and proteinuria are common side effects of treatment. However, the long-term toxicity of bevacizumab in this population has not been reported. METHODS: We reviewed the medical records of all NF2 patients treated with compassionate care bevacizumab at our institution. Hypertension was defined as a systolic blood pressure ≥140 or a diastolic blood pressure ≥90. Proteinuria was measured by urine dipstick. Time-to-event analyses were conducted for hypertension and proteinuria. The relationship of cumulative dose of bevacizumab to mean arterial pressure (MAP) was examined using mixed model analysis, while the relationship to urine protein was examined using generalized estimating equations. RESULTS: Thirty-three patients (median age 28 years) were included in the study, with a median treatment time of 34.1 months. 15/26 (58 %) patients became hypertensive and 18/29 (62 %) developed proteinuria during treatment. Median time to develop hypertension was 12.8 months. Median time to develop 1+ and 2+ proteinuria was 23.7 and 31.9 months, respectively. Eight patients required treatment holidays for proteinuria (median length 3.2 months). A significant positive relationship existed between cumulative bevacizumab dose and MAP (p < 0.0001) but not between cumulative dose and proteinuria (p > 0.30). CONCLUSION: In our cohort of NF2 patients, extended use of bevacizumab was associated with manageable toxicity. However, bevacizumab treatment still requires careful monitoring of blood pressure and proteinuria, and future studies should investigate optimal dosing schedules to minimize long-term toxicity.

Higher ghrelin and lower leptin secretion are associated with lower LH secretion in young amenorrheic athletes compared with eumenorrheic athletes and controls.

Amenorrhea is common in young athletes and is associated with low fat mass. However, hormonal factors that link decreased fat mass with altered gonadotropin pulsatility and amenorrhea are unclear. Low levels of leptin (an adipokine) and increased ghrelin (an orexigenic hormone that increases as fat mass decreases) impact gonadotropin pulsatility. Studies have not examined luteinizing hormone (LH) secretory dynamics in relation to leptin or ghrelin secretory dynamics in adolescent and young adult athletes. We hypothesized that 1) young amenorrheic athletes (AA) would have lower LH and leptin and higher ghrelin secretion than eumenorrheic athletes (EA) and nonathletes and 2) higher ghrelin and lower leptin would be associated with lower LH secretion. This was a cross-sectional study. We examined ghrelin and leptin secretory patterns (over 8 h, from 11 PM to 7 AM) in relation to LH secretory patterns in AA, EA, and nonathletes aged 14-21 yr. Ghrelin and leptin were assessed every 20 min and LH every 10 min. Groups did not differ for age, bone age, or BMI. However, fat mass was lower in AA than in EA and nonathletes. AA had lower LH and higher ghrelin pulsatile secretion and AUC than nonathletes and lower leptin pulsatile secretion and AUC than EA and nonathletes. Percent body fat was associated positively with LH and leptin secretion and inversely with ghrelin. In a regression model, ghrelin and leptin secretory parameters were associated independently with LH secretory parameters. We conclude that higher ghrelin and lower leptin secretion in AA related to lower fat mass may contribute to altered LH pulsatility and amenorrhea.