Effect of access to care on outcomes of rural and elderly patients with primary central nervous system lymphoma.

Abstract

e14008 Background: Primary central nervous system lymphoma (PCNSL) can often be cured, especially in younger patients, but requires intense chemotherapy with high-dose methotrexate (HDMTX) and rituximab to optimize outcomes. Toxicities can lead to dose reduction or omission that may increase relapse risk, or lead clinicians to select less effective regimens that do not contain HDMTX. Methods: Anonymized, de-identified data of patients from 110 community oncology practices of the Guardian Research Network (GRN, www.GuardianResearch.org ) was analyzed to determine treatments, toxicities, and outcomes of adults with PCNSL. All data from the medical record is available from GRN (diagnoses, demographics, labs, medicines, toxicities, radiology, pathology, procedures, and encounters), so each patient’s journey can be fully characterized. Results: Of 533805 adults with cancer, 49 were treated for PCNSL with HDMTX-containing regimens (n = 35), other chemotherapy regimens (n = 3), or radiation therapy (RT) alone (n = 11). HDMTX patients received HDMTX only in 8 cases, HDMTX plus rituximab in 23 cases, addition of RT in 11 cases, and HDMTX with other chemotherapy but no rituximab in 3 cases. Survival at 5 years was 53% (standard error [SE] 8.6%) for patients treated with HDMTX versus 33% (SE 13%) for those treated with other therapies. Of those treated with HDMTX, survival was 0% for patients who experienced early toxicity that required cessation of HDMTX prior to receiving 3 doses and having response evaluated versus 62% (SE 9.1%) for patients who received 3 or more courses of HDMTX (p < 0.001). In a multivariable Cox proportional hazards model including completion of at least 3 doses of HDMTX, age, race, and sex, only lack of HDMTX toxicity was associated with survival (hazard ratio 0.22, 95% confidence interval 0.07 to 0.70, p = 0.01). Conclusions: Use of HDMTX and prevention of toxicity improves outcomes for PCNSL patients treated in the community.