Faculty Bibliography

PURPOSE/OBJECTIVE:Primary central nervous system lymphoma (PCNSL) of T cell origin is rare in pediatric patients. We report a case of T cell PCNSL in a 12-year-old boy and review the literature to highlight the importance of brain biopsy to definitively establish the diagnosis when PCNSL is suspected. CASE REPORT/METHODS:A 12-year-old boy presented with worsening left-sided weakness, nausea, vomiting, headache, blurred vision, and diplopia. Magnetic resonance imaging revealed right parietal gyral thickening with faint meningeal contrast enhancement. No clear diagnosis was identified after serum testing, cerebrospinal fluid analysis, and cerebral angiography. To establish the diagnosis definitively, a right craniotomy and open, frameless stereotactic biopsy were performed, which yielded the diagnosis of lymphoblastic T cell lymphoma. CONCLUSIONS:PCNSL of T cell origin in children remains poorly studied, with only 18 detailed cases reported over the last three decades, including this case. Establishing a definitive diagnosis of PCNSL is challenging, and a brain biopsy is often required to obtain enough tissue for pathological analysis. Increasing awareness and identification of children diagnosed with T cell PCNSL is needed to better understand the molecular biology of this disease and develop more standardized treatment regimens.

Gliomatosis peritonei is a rare condition associated with ovarian teratomas. Even rarer is extraperitoneal gliomatosis. We present a case of extraperitoneal gliomatosis with pleural implants and implants within the flank muscles, which regressed after resection of the primary tumor.

BACKGROUND:Infants with acute lymphoblastic leukemia (ALL) have a poor prognosis. Intensification of therapy has resulted in fewer relapses but increased early deaths, resulting in failure to improve survival. PROCEDURE/METHODS:AALL0631 is a Phase 3 study for infants (<366 days of age) with newly diagnosed ALL. Induction initially (Cohort 1) consisted of 3 weeks of therapy based on COG P9407. Due to excessive early mortality, induction was amended to a less intensive 5 weeks of therapy based on Interfant-99. Additionally, enhanced supportive care guidelines were incorporated with hospitalization during induction until evidence of marrow recovery and recommendations for prevention/treatment of infections (Cohort 2). RESULTS:Induction mortality was significantly lower for patients in Cohort 2 (2/123, 1.6%) versus Cohort 1 (4/26, 15.4%; P = 0.009). All induction deaths were infection related except one due to progressive disease (Cohort 2). Sterile site infections were lower for patients in Cohort 2 (24/123, 19.5%) versus Cohort 1 (15/26, 57.7%; P = 0.0002), with a significantly lower rate of Gram positive infections during induction for patients in Cohort 2, P = 0.0002. No clinically significant differences in grades 3-5 non-infectious toxicities were observed between the two cohorts. Higher complete response rates were observed at end induction intensification for Cohort 2 (week 9, 94/100, 94%) versus Cohort 1 (week 7, 17/25, 68%; P = 0.0.0012). CONCLUSION/CONCLUSIONS:De-intensification of induction therapy and enhanced supportive care guidelines significantly decreased induction mortality and sterile site infections, without decreasing complete remission rates.

Acute lymphoblastic leukemia (ALL) in adolescents and young adults (AYA: 16-39 years) is characterized by distinct presenting features and inferior prognosis compared to pediatric ALL. To better understand the disease etiology in this age group, we performed a genome-wide association study (GWAS) to comprehensively identify inherited genetic variants associated with susceptibility to AYA ALL. In the discovery GWAS, we compared genotype frequency at 635,297 SNPs in 308 AYA ALL cases and 6,661 non-ALL controls by using a logistic regression model with European, African and Native American genetic ancestries as a covariates. SNPs that reached association P