Intraventricular methotrexate may improve survival for medulloblastoma subtypes
FROM THE JOURNAL OF CLINICAL ONCOLOGY
Non-WNT/non-SHH disease
Patients with non-WNT/non-SHH medulloblastoma (CMB or LCA) were divided into molecularly defined subtypes group 3 (n = 14) and group 4 (n = 6). The patients in group 3 had lower survival rates than patients in group 4. The 5-year PFS rate was 36% and 83%, respectively (P < .001 ). The 5-year OS rate was 49% and 100%, respectively (P < .001).
“This represents the third recent publication to describe a poor PFS for group 3, and it signals a desperate need for better therapy,” the editorialists wrote. As for the “encouraging” survival rate for group 4 patients, there were only six subjects, which makes this finding “worthy of follow-up but not actionable.”
Even so, the investigators noted that “although poor survival has been reported for non-SHH CMB/LCA in almost every series of patients treated with CSI-sparing approaches, again, use of intraventricular [methotrexate] might be associated with slightly higher PFS, compared with conventional chemotherapy alone.”
As expected, IQ was significantly lower in patients who received CSI salvage. The mean IQ was 74 in patients who received CSI and 90 in patients who did not (P = .012). Neurocognitive outcomes were poor in general among CMB/LCA survivors, “which was closely related to use of radiotherapy,” according to the investigators.
“It is important to recognize that these studies were not designed to define outcome on the basis of molecular subgroup or subtype and that the sample size in all these studies is small,” Dr. Robinson and Dr. Gajjar wrote. “Thus, caution should be used when basing any treatment recommendation on these results, and it is our strong-held opinion that any treatment change be done on a well-planned and well-monitored clinical trial.”
This research was supported by the German Childhood Cancer Foundation, Styrian Childhood Cancer Foundation, and other organizations. Dr. Mynarek and colleagues disclosed relationships with Medac, Novartis, Eli Lilly, Bayer, Roche, and numerous other companies. Dr. Robinson disclosed relationships with Eli Lilly, Genentech, and Novartis. Dr. Gajjar reported relationships with Genentech and Kazia Therapeutics.
SOURCE: Mynarek M et al. J Clin Oncol. 2020 Jun 20;38(18):2028-40.
