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Stuart A Grossman

Publications and source records attributed to Stuart A Grossman.

At least 19 recordsLinked to original sources
PubMed2007

Venous thromboembolism occurs infrequently in meningioma patients receiving combined modality prophylaxis.

BACKGROUND: Individuals with brain tumors have an increased risk of venous thromboembolism (VTE). Within this population, patients with meningiomas have been reported to have the highest incidence, exceeding rates associated with gliomas and brain metastases. However, earlier studies did not employ VTE prophylaxis, and VTE were detected with radionuclide scans, the reliability of which has since been questioned. Therefore, we conducted a retrospective review of postoperative meningioma patients receiving contemporary VTE prophylaxis and diagnostic methods to define the current incidence of and risk factors for symptomatic VTE in this population. METHODS: Medical records were reviewed from all patients undergoing craniotomy for meningioma at Johns Hopkins Hospital in 2004 and 2005. The association between clinical characteristics and VTE was assessed using parametric and nonparametric statistical tests and survival analysis. RESULTS: A total of 224 individuals met criteria for the review. The mean age was 52 years (standard deviation [SD] 14 years), and 167 patients (75%) were women. Median follow-up time was 230 days (interquartile range [IQR], 89-428 days). VTE was diagnosed in 11 patients (4.9%; 95% confidence interval, 2.5%-8.6%) at a median of 16 days (IQR, 7-33 days) postoperatively. The development of VTE was associated with older age (mean, 68 years vs 52 years; P = .0001), male gender (P = .007), and nonambulatory status postoperatively (P < .0001). CONCLUSIONS: VTE occurs infrequently in postoperative meningioma patients who receive combined modality VTE prophylaxis. VTE risk factors in these patients include advanced age, male gender, and nonambulatory status postoperatively.

Adult↗
PubMed2006

Epigenetic silencing of multiple genes in primary CNS lymphoma.

Epigenetic silencing of functionally important genes is important in the development of malignancies and is a source of potential markers for molecular detection. Primary central nervous system lymphoma (PCNSL) is an increasingly common tumor that has not been extensively examined for changes in promoter region methylation. We examined 14 tumor suppressor genes in 25 cases of PCNSL using methylation-specific PCR. Methylation was observed in DAPK (84%), TSP1 (68%), CRBP1 (67%), p16(INK) (4a) (64%), p14(ARF) (59%), MGMT (52%), RARbeta2 (50%), TIMP3 (44%), TIMP2 (42%), p15(INK) (4b) (40%), p73 (28%), hMLH1 (12%), RB1 (8%) and GSTP1 (8%). Promoter methylation of p14(ARF), p16(INK) (4a) and MGMT was correlated with loss of expression by immunohistochemical staining. The methylation of many of these genes in PCNSL is similar to that reported in other high-grade B-cell lymphomas. All 25 cases of PCNSL had methylation of at least 2 genes. Methylation of DAPK, p16(INK) (4a) or MGMT was found in 96% of the tumors, suggesting simple marker strategies to detect circulating methylated DNA in serum that might facilitate early tumor detection. Our study provides insight into the epigenetic alterations in PCNSL and provides potential biomarkers of disease.

Adult↗
PubMed2006

The impact of thrombocytopenia from temozolomide and radiation in newly diagnosed adults with high-grade gliomas.

Temozolomide (TMZ) administered daily with radiation therapy (RT) for six weeks, followed by adjuvant TMZ for six months, has become standard therapy for patients with glioblastoma multiforme (GBM). After several newly diagnosed patients at our institution developed severe (grade 3-4), prolonged thrombocytopenia, we conducted a retrospective review to define the incidence, depth, and duration of thrombocytopenia associated with this therapy. We reviewed the medical records and laboratory data of all adult patients with newly diagnosed high-grade gliomas who started treatment with this regimen between June 2004, when the regimen was first used at our institution, and August 2005. Of the 52 patients who met the criteria for this review, grade 3-4 thrombocytopenia occurred in 10 (19%; 95% CI, 10%-33%). In eight patients, the thrombocytopenia was attributable to concurrent daily TMZ and RT. The median duration of grade 3-4 thrombocytopenia was 32 days (range, 1-389 days). Five patients (10%) required platelet transfusions, two (4%) have required continued biweekly platelet transfusions for over six months, and nine (17%) discontinued therapy because of thrombocytopenia. Grade 3-4 thrombocytopenia occurred in 25% of women and 14% of men. Grade 3-4 neutropenia and anemia were noted in 10% and 8% of patients, respectively, and were not clinically significant. Between 15% and 20% of our newly diagnosed patients receiving TMZ and RT developed severe (grade 3-4) and potentially irreversible thrombocytopenia. The factors that predispose patients to this toxicity have yet to be determined. This toxicity should be considered when (1) prescribing this regimen to patient populations where a clinical benefit has yet to be shown, (2) contemplating empirical escalations of the dose or duration of TMZ, or (3) combining it with other potentially myelosuppressive therapies.

Adult↗
PubMed2006

Phase II clinical and pharmacologic study of radiation therapy and carboxyamido-triazole (CAI) in adults with newly diagnosed glioblastoma multiforme.

INTRODUCTION: Carboxyamido-triazole (CAI) is a synthetic inhibitor of non-voltage-gated calcium channels that reversibly inhibits angiogenesis, tumor cell proliferation, and metastatic potential. This study examined the efficacy, safety and pharmacokinetics of oral CAI in the treatment of patients with newly diagnosed glioblastoma multiforme (GBM) in an open-label, single arm non-randomized phase 2 trial. METHODS: Eligible patients with histologically confirmed GBM started CAI therapy (250 mg daily) on the first day of radiation (6000 cGy in 30 fractions) and continued until progression, unless side effects became intolerable. The primary outcome was survival compared to historical controls within the NABTT CNS Consortium database. Secondary outcomes included toxicity and pharmacokinetic parameters. RESULTS: Fifty-five patients were enrolled with a median Karnofsky performance status of 90 and age of 56 years. Forty-six (84%) of these patients had debulking surgeries and 52 have died. The median survival was 10.3 months (95% confidence interval (CI), 8.5-12.8) compared to 12.1 months (95% CI, 10.3-13.3) in the NABTT reference group (p = 0.97). Significant toxicities included 2 incidents of reversible vision loss. The mean CAI plasma concentration for patients taking enzyme inducing antiepileptic drugs (EIAED) was 1.35 +/-1.22 compared to 4.06 +/- 1.50 (p < 0.001) for subjects not taking these agents. Overall survival and grade > or = 3 toxicities were comparable by EIAED status. CONCLUSIONS: This study demonstrated that (1) CAI can be administered safely with concomitant cranial irradiation, (2) the pharmacokinetics of CAI are significantly affected by co-administration of EIAED, and (3) the survival of patients with newly diagnosed GBM was not improved with this novel agent, despite achieving adequate drug levels.

Administration, Oral↗
PubMed2006

Calculated versus measured creatinine clearance for dosing methotrexate in the treatment of primary central nervous system lymphoma.

BACKGROUND: High-dose methotrexate (HDMTX) (>or=3 g/m2), the cornerstone of therapy for primary CNS lymphoma (PCNSL), is commonly dosed using a measured 24 h creatinine clearance (CrCl) every 2-4 weeks. Because these collections are cumbersome and at times unreliable, the use of a calculated CrCl was evaluated as a potential alternative. METHODS: A retrospective analysis was performed on data from all 287 treatment cycles from the 25 patients with PCNSL who participated in a multi-center phase II clinical trial of HDMTX conducted by the New Approaches to Brain Tumor Therapy (NABTT) CNS Consortium. RESULTS: The 25 patients had a median age of 61 years (range 32-75). Seventeen (68%) were men. The patients received a median of 14 (range 2-21) HDMTX treatments. For 256 of 287 treatments (89%), data were available to compare the measured and calculated (using the Cockcroft-Gault equation) CrCl. The average measured CrCl was 93 ml/min (95% CI, 89-96 ml/min), and the average calculated CrCl was 107 ml/min (95% CI, 102-112 ml/min). The Pearson correlation coefficient (r) was 0.49 (P<0.0001) between the measured and calculated CrCl. The average MTX dose determined using measured CrCl was 14.1 g (95% CI, 13.6-14.5 g), and the average MTX dose determined using calculated CrCl was 14.7 g (95% CI, 14.2-15.1 g). MTX doses based on measured and calculated CrCl were significantly correlated (r=0.72, P<0.0001). Of the 256 HDMTX treatments evaluated, 158 (62%) had reliable 48 h serum MTX levels documented. Forty-seven levels (30%) were within target range (0.3-1 micromol/l), 99 levels (62%) were below target range (<0.3 micromol/l), 12 levels (8%) were in the range associated with mild toxicity range (>1-3 micromol/l), and no levels were in the range associated with severe toxicity (>3 micromol/l). Of these 158 treatments, the use of a calculated rather than measured CrCl would have yielded an identical MTX dose for 48 treatments (30%), a higher MTX dose for 62 treatments (40%), and a lower MTX dose for 48 treatments (30%). This distribution was not significantly different among the subsets of below target, within target range, and above target MTX levels (P=0.87). CONCLUSIONS: In this cohort of patients with PCNSL, there is significant correlation between the calculated and measured CrCl. MTX doses determined using calculated and measured CrCl are not significantly different. For these patients, there is no clear association between the method of determining CrCl and serum MTX levels. As a result, calculated CrCl is a reasonable alternative to measured CrCl in this patient population and would avoid the inconvenience and potential inaccuracies associated with measured CrCl.

Adult↗
PubMed2006

The effect of enzyme-inducing antiseizure drugs on the pharmacokinetics and tolerability of procarbazine hydrochloride.

PURPOSE: Procarbazine hydrochloride (PCB) is one of the few anticancer drugs with activity against high-grade gliomas. This study was conducted to determine if the maximum tolerated dose and pharmacokinetics of PCB are affected by the concurrent use of enzyme-inducing antiseizure drugs (EIASD). EXPERIMENTAL DESIGN: Adults with recurrent high-grade glioma were divided into cohorts who were (+) and were not (-) taking EIASDs. PCB was given orally for 5 consecutive days each month. Six patients were evaluated at each dose level beginning with 200 mg/m2/d and escalated using the modified continual reassessment method. Toxicity and response were assessed. Pharmacokinetic studies were done with a new electrospray ionization mass spectrometry assay. RESULTS: Forty-nine patients were evaluated. The maximum tolerated dose was 393 mg/m2/d for the +EIASD group and the highest dose evaluated in -EIASD patients was 334 mg/m2/d. Myelosuppression was the primary dose-limiting toxicity. Significant hepatic dysfunction occurred in three patients in the +EIASD cohort. Four partial responses (8%) and no complete responses were observed. PCB exhibited linear pharmacokinetics with no significant differences between the two cohorts. A marked increase in peak PCB levels was noted on day 5 relative to day 1, which was not attributable to drug accumulation. CONCLUSIONS: This study suggests that (a) EIASD use does not significantly affect the pharmacokinetics of PCB; (b) changes in the peak plasma concentration of PCB, consistent with decreased apparent oral clearance due to autoinhibition of hepatic metabolism, occur with daily dosing; and (c) severe hepatic dysfunction may accompany this administration schedule.

Administration, Oral↗
PubMed2006

Management of venous thromboembolism in patients with primary and metastatic brain tumors.

Venous thromboembolism occurs commonly throughout the clinical course of patients with brain tumors. A number of hemostatic and clinical factors contribute to this hypercoagulable state. Concern over the possibility of intracranial bleeding has limited the use of anticoagulation in this population. However, mechanical approaches such as vena cava filters have high complication and treatment failure rates in patients with intracranial malignancies. In addition, the available data suggest that anticoagulation can be used safely and effectively in most of these patients. Patients with thrombocytopenia, recent neurosurgery, and tumor types prone to bleeding require special consideration. When intracranial hemorrhage does occur, it is often due to overanticoagulation, requiring prompt anticoagulation reversal and neurosurgical consultation.

Anticoagulants↗
PubMed2006

Initial response to glucocorticoids.

BACKGROUND: Known prognostic variables in patients with primary central nervous system lymphomas (PCNSL) include age, Karnofsky performance status, involvement of deep regions of the brain, intensity of blood-brain barrier disruption, and treatment with radiation and chemotherapy. PCNSL often responds transiently to glucocorticoids administered to control neurologic symptoms before radiation or chemotherapy. This retrospective chart review was designed to estimate the prognostic significance of a clinical or radiologic response to initial glucocorticoid therapy. METHODS: By using data from The Johns Hopkins Cancer Registry from January 1980 to June 2001, a total of 76 human immunodeficiency virus (HIV)-negative adults with newly diagnosed PCNSL were identified. Nineteen patients with uninformative medical records were excluded from the study. RESULTS: The median survival of the remaining 57 patients was 11.8 months. The median survival for the 48 patients who had clinical response to initial steroid therapy was 17.9 months, and for nonresponders, it was 5.5 months (P = 0.05). The 16 patients with documented radiologic response had a median survival of 117.0 months compared with 5.5 months for nonresponders (P = 0.001). After adjusting for known prognostic factors (age and treatment), significant reduction in risk of death was noted in patients who had either clinical (hazard ratio [HR] = 0.40; 95% confidence interval [CI], 0.16-0.99}) or radiologic response (HR = 0.14; 95% CI, 0.04-0.46) to glucocorticoids given before radiation or chemotherapy. CONCLUSION: This analysis suggests that initial response to treatment with glucocorticoids may be an important prognostic factor in patients with PCNSL.

Adult↗
PubMed2006

Management of pineal region tumors.

Tumors of the pineal region represent a diverse collection of tumors with a variety of natural histories. This diversity necessitates accurate histologic diagnosis to allow rational therapeutic planning. Evaluation of a pineal lesion should begin with craniospinal MRI and analysis of the cerebrospinal fluid (CSF). Whereas certainty of the histologic diagnosis is now a requirement for treatment in Western nations, some Asian centers continue to recommend a test dose of radiation therapy based on the high incidence of germinoma in those countries. If there is high clinical suspicion of a germinoma or tectal glioma, stereotactic or endoscopic biopsy may be pursued. All other lesions should be referred for open biopsy with microsurgical techniques. This approach provides adequate tissue for diagnosis, may be curative in low-grade tumors, and may substantially improve survival in patients with malignant tumors. If open surgery is not desired by the patient or practitioner, stereotactic or endoscopic biopsy may be followed by radiosurgery for localized, well-demarcated tumors. Radiation therapy is the first-line therapy for germinomas. Although the optimal radiation dosage and volume have not been decided, the current Children's Oncology Group trial may offer definitive evidence to address this dilemma in germ cell tumors. Evidence of CSF seeding requires craniospinal radiation and adjuvant chemotherapy regardless of tumor type. Diagnosis of any of the malignant tumors (non-germ cell tumors, pineoblastomas, and parenchymal tumors of intermediate determination) also requires craniospinal radiation (with local tumor doses of at least 50 Gy) and adjuvant chemotherapy (generally platinum based). Patients with tectal gliomas may undergo excision with or without postoperative radiation; however, they also may be observed with vigilant follow-up alone.

Brain Neoplasms↗
PubMed2006

Methylated tumor-specific DNA as a plasma biomarker in patients with glioma.

OBJECTIVE: Patients with systemic malignancies have substantial quantities of tumor-specific DNA in their plasma which may serve as a potential biomarker for tumor burden. This approach has not been studied in gliomas. METHODS: Methylation specific polymerase chain reaction (MSP) was used to determine the methylation status the promoters for p16/(INK4a), MGMT, p73, and RARbeta within glioma tissue and plasma. Blood was collected prior to craniotomy in 10 patients with glioma. DNA was extracted from tumor and plasma samples and assayed with MSP. Total plasma DNA also was quantified. Tumor-specific plasma DNA was defined as identification of the same methylated promoter (MP) in both tumor and plasma. RESULTS: Total plasma DNA concentration was markedly elevated (mean 6,503 ng/ml, SEM 1,400 ng/ml). Glioma tissue contained methylation of at least one promoter in 9 out of 10 (90 percent) of patients studied. Of these patients, 6 out of 9 (67 percent) demonstrated methylation of at least one of the same promoters in plasma. Five of these had one MP identified in the plasma and one had 2 MP. Overall, glioma-specific plasma DNA was present in plasma of 6 out of 10 (60 percent) of patients. Each MP DNA marker found in the plasma also was present in the intracranial tumor. CONCLUSIONS: Patients with high grade gliomas have large amounts of DNA in the plasma. Of these primary brain tumors, 90 percent contained methylated gene promoters, and in over 60 percent of these patients the same methylated promoters present in the tumor also were found in the plasma. This represents the first step to developing a quantitative plasma biomarker that could be used to monitor glioma status.

Adult↗
PubMed2006

Cancer pain management in the 21st century.

Cancer causes pain as it invades bone, compresses nerves, produces obstructive symptoms in the pulmonary, gastrointestinal, and genitourinary systems, and distends involved visceral organs. This manuscript reviews progress in cancer pain management during the past 2 decades. Since the 1980s, we have seen (1) genuine advances in research on the biology of pain, (2) new approaches to the treatment of cancer pain, and (3) important changes in the health-care system to ensure that pain is appropriately assessed and managed. Currently, clinicians have the appropriate diagnostic and therapeutic tools to ensure that the vast majority of patients with cancer pain can be comfortable during their illness. Nevertheless, too many patients with terminal malignancies continue to die in pain in nations around the globe. An effective strategy to make alleviating pain a major health-care priority remains the primary challenge to effectively palliating patients with cancer pain.

History, 20th Century↗
PubMed2005

Efficacy and toxicity of the antisense oligonucleotide aprinocarsen directed against protein kinase C-alpha delivered as a 21-day continuous intravenous infusion in patients with recurrent high-grade astrocytomas.

Protein kinase C alpha (PKC-alpha) is a cytoplasmic serine threonine kinase involved in regulating cell differentiation and proliferation. Aprinocarsen is an antisense oligonucleotide against PKC-alpha that reduces PKC-alphain human cell lines and inhibits a human glioblastoma tumor cell line in athymic mice. In this phase 2 study, aprinocarsen was administered to patients with recurrent high-grade gliomas by continuous intravenous infusion (2.0 mg/kg/day for 21 days per month). Twenty-one patients entered this trial. Their median age was 46 years (range, 28-68 years), median Karnofsky performance status was 80 (range, 60-100), median tumor volume was 58 cm3 (range, 16-254 cm3), and histology included glioblastoma multiforme (n = 16), anaplastic oligodendroglioma (n = 4), and anaplastic astrocytoma (n = 1). The number of prior chemotherapy regimens included none (n = 3), one (n = 10), and two (n = 8). No tumor responses were observed. Patients on this therapy rapidly developed symptoms of increased intracranial pressure with increased edema, enhancement, and mass effect on neuroimaging. The median time to progression was 36 days, and median survival was 3.4 months. The observed toxicities were mild, reversible, and uncommon (grade 3 thrombocytopenia [n = 3] and grade 4 AST [n = 1]), and no coagulopathy or CNS bleeding resulted from this therapy. Plasma concentrations of aprinocarsen during the infusion exhibited significant interpatient variability (mean = 1.06 mug/ml; range, 0.34-6.08 mug/ml). This is the first study to use an antisense oligonucleotide or a specific PKC-alpha inhibitor in patients with high-grade gliomas. No clinical benefit was seen. The rapid deterioration seen in these patients could result from tumor growth or an effect of aprinocarsen on bloodbrain barrier integrity.

Adult↗
PubMed2005

Oral sodium phenylbutyrate in patients with recurrent malignant gliomas: a dose escalation and pharmacologic study.

We determined the maximum tolerated dose (MTD), toxicity profile, pharmacokinetic parameters, and preliminary efficacy data of oral sodium phenylbutyrate (PB) in patients with recurrent malignant gliomas. Twenty-three patients with supratentorial recurrent malignant gliomas were enrolled on this dose escalation trial. Four dose levels of PB were studied: 9, 18, 27, and 36 g/day. Data were collected to assess toxicity, response, survival, and pharmacokinetics. All PB doses of 9, 18, and 27 g/day were well tolerated. At 36 g/day, two of four patients developed dose-limiting grade 3 fatigue and somnolence. At the MTD of 27 g/day, one of seven patients developed reversible grade 3 somnolence. Median survival from time of study entry was 5.4 months. One patient had a complete response for five years, and no partial responses were noted, which yielded an overall response rate of 5%. Plasma concentrations of 706, 818, 1225, and 1605 muM were achieved with doses of 9, 18, 27, and 36 g/day, respectively. The mean value for PB clearance in this patient population was 22 liters/h, which is significantly higher than the 16 liters/h reported in patients with other malignancies who were not receiving P450 enzyme-inducing anticonvulsant drugs (P = 0.038). This study defines the MTD and recommended phase 2 dose of PB at 27 g/day for heavily pretreated patients with recurrent gliomas. The pharmacology of PB appears to be affected by concomitant administration of P450-inducing anticonvulsants.

Administration, Oral↗
PubMed2005

Phase 2 trial of copper depletion and penicillamine as antiangiogenesis therapy of glioblastoma.

Penicillamine is an oral agent used to treat intracerebral copper overload in Wilson's disease. Copper is a known regulator of angiogenesis; copper reduction inhibits experimental glioma growth and invasiveness. This study examined the feasibility, safety, and efficacy of creating a copper deficiency in human glioblastoma multiforme. Forty eligible patients with newly diagnosed glioblastoma multiforme began radiation therapy (6000 cGy in 30 fractions) in conjunction with a low-copper diet and escalating doses of penicillamine. Serum copper was measured at baseline and monthly. The primary end point of this study was overall survival compared to historical controls within the NABTT CNS Consortium database. The 25 males and 15 females who were enrolled had a median age of 54 years and a median Karnofsky performance status of 90. Surgical resection was performed in 83% of these patients. Normal serum copper levels at baseline (median, 130 microg/dl; range, 50-227 microg/dl) fell to the target range of <50 microg/dl (median, 42 microg/dl; range, 12-118 microg/dl) after two months. Penicillamine-induced hypocupremia was well tolerated for months. Drug-related myelosuppression, elevated liver function tests, and skin rash rapidly reversed with copper repletion. Median survival was 11.3 months, and progression-free survival was 7.1 months. Achievement of hypocupremia did not significantly increase survival. Although serum copper was effectively reduced by diet and penicillamine, this antiangiogenesis strategy did not improve survival in patients with glioblastoma multiforme.

Brain Neoplasms↗
PubMed2004

Treatment of relapsed central nervous system lymphoma with high-dose methotrexate.

PURPOSE: Over the past decade, high-dose methotrexate has emerged as the single most effective agent in the initial treatment of primary nervous system lymphoma. However, the majority of patients who respond initially to treatment relapse. The optimal management of these patients has not been determined. We performed a multicenter, retrospective study of high-dose methotrexate in patients with relapsed central nervous system lymphoma. EXPERIMENTAL DESIGN: Patients with relapsed disease were eligible if they achieved a complete response to initial treatment with methotrexate-based chemotherapy or received methotrexate after gross total resection or interstitial radiation. All of the patients were retreated with a regimen containing high-dose methotrexate (>/=3 g/m(2)). RESULTS: Twenty-two patients with a median age of 58 years were included in the study. Overall response rates were 91% to first salvage (20 of 22 patients) and 100% to second salvage (4 of 4 patients). Median survival was 61.9 months after first relapse (95% confidence interval, 42.1- infinity ) and 91.9 months overall (95% confidence interval, 47.2- infinity ). Toxicity was primarily hematologic with 10 episodes of grade 3 or 4 toxicity during 566 cycles of chemotherapy. CONCLUSIONS: These results indicate that high-dose methotrexate remains effective for relapsed central nervous system lymphoma in patients who initially respond to methotrexate and raise the possibility of deferring more toxic salvage regimens in this select group of patients.

Adult↗
PubMed2004

ABO blood group is a potent risk factor for venous thromboembolism in patients with malignant gliomas.

BACKGROUND: Venous thromboembolism (VTE) is a common cause of morbidity and mortality among patients with malignant gliomas. To investigate the pathogenesis of VTE and facilitate targeted prophylaxis strategies, the authors aimed to characterize VTE risk factors in these patients. METHODS: The authors conducted a retrospective chart review of 130 adult patients with glioma who received their primary therapy at the Johns Hopkins Hospital (Baltimore, MD) between 1991 and 2001. Symptomatic VTE was confirmed by objective radiologic testing. The association between clinical and laboratory characteristics and VTE was assessed using parametric and nonparametric statistical tests and survival analysis. RESULTS: VTE developed in 28 patients (21.5%) at a median of 4.8 months after diagnosis (interquartile range, 2.1-13.2). Patients with tumors > 5 cm were more likely to develop VTE than patients with smaller tumors (hazard ratio = 2.2; P = 0.04). For every year increase in age, the hazard ratios for thrombosis increased by 3% (P = 0.011). When stratified by ABO blood group, the hazard ratios for thrombosis were 2.7 and 9.4 for patients with blood groups A (P = 0.045) and AB (P < 0.0001), respectively, compared with patients with blood group O. No association was observed between VTE and the other patient characteristics analyzed. CONCLUSIONS: Patient age, tumor size, and particularly ABO blood group are risk factors for VTE among patients with malignant gliomas. These findings may facilitate the development of a thrombosis risk score that will allow physicians to individualize VTE prophylaxis regimens.

ABO Blood-Group System↗