Hemolytic anemia in two patients with glioblastoma multiforme: A possible interaction between vorinostat and dapsone.

Patients undergoing treatment for glioblastoma multiforme are routinely placed on prophylactic treatment for Pneumocystis jirovecii pneumonia because of significant therapy-induced lymphopenia. In patients with sulfa allergies, dapsone prophylaxis is often used due to its efficacy, long half-life, cost effectiveness, and general safety at low doses. However, dapsone may uncommonly induce a hemolytic anemia, particularly in patients deficient of glucose-6-phosphate dehydrogenase. This hemolysis is thought to be a result of oxidative stress on red blood cells induced by dapsone metabolites which produce reactive oxygen species that disrupt the red blood cell membrane and promote splenic sequestration. A single case report of dapsone-induced hemolytic anemia in a patient with glioblastoma multiforme has been reported. We present two patients with glioblastoma multiforme who developed severe hemolytic anemia shortly after initiating therapy with vorinostat, a pan-active histone deacetylase inhibitor, while on prophylactic dapsone. There are several potential mechanisms by which histone deacetylase inhibition may alter dapsone metabolism including changes in hepatic acetylation or N-glucuronidation leading to an increase in the bioavailability of dapsone's hematotoxic metabolites. In addition, vorinostat may lead to increased hemolysis through inhibition of heat shock protein-90, a chaperone protein that maintains the integrity of the red blood cell membrane cytoskeleton. The potential interaction between dapsone and vorinostat may have important clinical implications as more than 10 clinical trials evaluating drug combinations with vorinostat in patients with malignant glioma are either ongoing or planned in North America.

Analysis of salivary fluid and chemosensory functions in patients treated for primary malignant brain tumors.

OBJECTIVES: The frequency and causes of chemosensory (taste and smell) disorders in cancer patients remain under-reported. This study examined the impact of cancer therapy on taste/smell functions and salivary constituents in brain tumor patients. MATERIALS AND METHODS: Twenty-two newly diagnosed patients with primary malignant gliomas underwent 6 weeks of combined modality treatment (CMD) with radiation and temozolomide followed by six monthly cycles of temozolomide. Chemosensory functions were assessed at 0, 3, 6, 10, 18, and 30 weeks with paired samples of saliva collected before and after an oral rinse with ferrous-spiked water. Iron (Fe)-induced oxidative stress was measured by salivary lipid oxidation (SLO); salivary proteins, electrolytes, and metals were determined. Parallel salivary analyses were performed on 22 healthy subjects. RESULTS: Chemosensory complaints of cancer patients increased significantly during treatment (p = 0.04) except at 30 weeks. Fe-induced SLO increased at 10 and 18 weeks. When compared with healthy subjects, SLO, total protein, Na, K, Cu, P, S, and Mg levels, as averaged across all times, were significantly higher (p < 0.05), whereas salivary Zn, Fe, and oral pH levels were significantly lower in cancer patients (p < 0.05). Neither time nor treatment had a significant impact on these salivary parameters in cancer patients. CONCLUSIONS: Impact of CMT treatment on chemosensory functions can range from minimal to moderate impairment. Analysis of SLO, metals, and total protein do not provide for reliable measures of chemosensory dysfunctions over time. CLINICAL RELEVANCE: Taste and smell functions are relevant in health and diseases; study of salivary constituents may provide clues on the causes of their dysfunctions.

Influenza vaccine immunogenicity in patients with primary central nervous system malignancy.

BACKGROUND: Patients with central nervous system (CNS) malignancies represent an "at-risk" population for contracting influenza, particularly if they are receiving ongoing chemotherapy, radiation, and/or glucocorticoid treatment. The Centers for Disease Control endorses vaccination for these patients, although data are not available to indicate whether they mount an immunologic response adequate to achieve clinical protection. METHODS: A pilot prospective cohort study was designed to evaluate the immunogenicity of the standard-dose trivalent inactivated influenza vaccine in patients with malignant CNS tumors. Baseline data collection included diagnosis, chemotherapy, timing of chemotherapy or radiation relative to vaccination, and glucocorticoid dose. Serum samples were collected at baseline, day 14, day 28, and month 3 following vaccination. Samples were tested using hemagglutinin inhibition to determine seroconversion (4-fold rise in titer) and seroprotection (titer >1:40). RESULTS: A total of 38 patients were enrolled (mean age, 54 years ±13.5 years, 60.5% male, 94.7% Caucasian, and 5.3% African American). CNS tumor diagnoses included glioblastoma multiforme (55.2%), other high-grade glioma (13.2%), low-grade glioma (15.8%), and primary CNS lymphoma (15.8%). At enrollment, 20 patients (52.6%) were taking glucocorticoids, 25 (65.8%) were on active chemotherapy, and 3 (7.9%) were undergoing radiation. Seroconversion rates at day 28 for the A/H1N1, A/H3N2, and B strains were 37%, 23% and 23%, respectively. Seroprotection was 80%, 69%, and 74%, respectively. All rates were significantly lower than published rates in healthy adults (P < .001). CONCLUSION: Influenza vaccine immunogenicity is significantly reduced in patients with CNS malignancies. Future studies are needed to determine the causative etiologies and appropriate vaccination strategies.

An automated system for detecting nonadherence in laboratory testing and monitoring for myelosuppression in patients receiving self-administered oral chemotherapy.

INTRODUCTION: Patient compliance with routine monitoring for self-administered chemotherapy is problematic. We sought to assess monitoring lapses and incidents of myelosuppression in patients undergoing self-administered chemotherapy for glioblastoma, as well as test software designed to detect and alert clinicians to lapses in monitoring. PATIENTS AND METHODS: A retrospective analysis was conducted to identify patients (N=117) who received standard oral temozolomide for glioblastoma at our institution from 2003 to 2010. Gaps in monitoring were classified as minor (10 to 12 days) or major (13 to 28 days), and adverse events were graded using standard criteria. During the prospective portion of the study, we tested a software-based system that alerted clinicians of monitoring lapses and adverse events among patients receiving self-administered temozolomide for glioblastoma (n=37). RESULTS: Our retrospective review found that 34 of 117 patients experienced monitoring gaps during treatment. No association between gaps and risk of myelosuppression were found. Patients with gaps were more likely to be male (P=.04). Patients monitored prospectively with the software experienced no major gaps in monitoring (P=.007 compared with retrospective patients). CONCLUSION: Our retrospective review demonstrated that monitoring nonadherence was occurring at a substantial rate. Our computerized system eliminated major gaps in monitoring in the prospective portion of our study. Although there is no association between monitoring gaps and the occurrence of adverse events, when they do coincide, continuing oral chemotherapy during an unrecognized adverse event may worsen the patient's condition. Automated systems are justified and serve a function not currently being addressed.

Phase I study of lenalidomide in solid tumors.

BACKGROUND: The primary objectives of this phase I study were to define a tolerable dose and to describe the toxicity of lenalidomide administered as a daily oral dose for 4 weeks followed by a 2-week rest period (6-week cycle) in patients with solid tumors that were refractory to standard treatment. The secondary objective was to document any antitumor activity. METHODS: Key eligibility criteria included a performance status of 0-2 and acceptable hematologic, hepatic, and renal function. The dose was escalated from 5 to 10 to 25 mg/day. Nine cycles (54 weeks) were planned unless the patient developed intolerable toxicity or experienced tumor progression. Dose-limiting toxicity was defined as nonhematologic toxicity of grade 3 or higher and hematologic toxicity of grade 4 or higher occurring in cycle 1. RESULTS: Overall, 20 patients were enrolled. One patient was ineligible due to a thromboembolic event within the preceding 6 months, but this was not known at enrollment and this patient was included in the analysis. Three, five, and 12 patients were treated with 5, 10, and 25 mg/day, respectively. One patient on 25 mg/day developed grade 3 motor neuropathy in cycle 1, and this was the only dose-limiting toxicity. Moderate dose-dependent and reversible hematologic toxicity was observed. The nonhematologic toxicities were otherwise mild to moderate over multiple cycles of lenalidomide. One patient had a partial response, and three patients had stable disease; three of these patients had non-small cell lung cancer. CONCLUSION: The recommended dose of lenalidomide for further studies in patients with solid tumors is 25 mg/day for 4 weeks followed by a 2-week rest period.

Vinorelbine, doxorubicin, and prednisone in androgen-independent prostate cancer.

BACKGROUND: Ultimately, patients with metastatic prostate cancer progress on androgen ablation therapy. The investigation of new chemotherapeutic regimens for the treatment of androgen-independent prostate cancer (AIPC) is essential. The authors conducted a Phase II trial with vinorelbine, doxorubicin, and daily prednisone (NAP) to investigate the antitumor activity and palliative response of this regimen in patients with AIPC. METHODS: Forty-six patients entered this Phase II combination chemotherapy trial. Patients were treated with both vinorelbine and doxorubicin at doses of 20 mg/m2 on Days 1, 8, and 15 every 28 days and prednisone 5 mg twice daily. Endpoints included prostate-specific antigen (PSA) response and palliation, as measured by the Functional Assessment of Cancer Therapy-Prostate (FACT-P) instrument, the Brief Pain Inventory Scale, and a narcotic analgesic log. RESULTS: The median follow-up for all 46 patients was 13.4 months. Fifty-two percent of patients had impaired performance status at baseline. One responding patient remained on NAP and was progression-free at 11.5 months. Thirty-nine patients progressed, 3 patients died prior to response assessment, and 3 patients refused therapy. The median overall survival was 57 weeks (95% confidence interval [95% CI], 36-76 weeks), and the median time to disease progression was 17 weeks (range, 11-24 weeks). The PSA response among the 36 patients who completed 3 cycles of NAP was 42% (95% CI, 26-59%). There was a statistically significant improvement in quality of life measured both by the FACT-General instrument (P = .03) and the FACT-P instrument (P = .0006) over the 3 months compared with baseline measurements. Pain medicine use also improved: The median morphine equivalents among patients who were taking pain medications at the time of study enrollment showed a substantial decline after 1 cycle of treatment that was maintained. Pain (as assessed by the Brief Pain Inventory) improved compared with baseline pain at the 2nd-month assessment (worst pain, P = .08; least pain, P = .02; and average pain, P = .003). Overall, the regimen was tolerated well. The most common side effects were mild fatigue and gastrointestinal complaints (all of which were Grade 1 or 2 [according to Version 2.0 of the Expanded Common Toxicity Criteria]). Seventeen patients (37%) experienced Grade 3 or 4 neutropenia. Five patients (11%) developed a cardiac ejection fraction of <50% during treatment and had doxorubicin discontinued. No patients developed clinical congestive heart failure. CONCLUSIONS: The NAP combination produced substantive palliation and a moderate response rate in men with AIPC.