Juvenile Pilocytic Astrocytoma treatment - Carboplatin and Vincristine

Hello - My 3 and a half year old son was recently diagnosed with a JPA on the tectal plate of this brain stem. The surgeon was able to resect 50% of the tumor and added that complete resection is possible, but may lead to long term effects, such as loss of hearing. His oncologist wants to immediately put him on a chemo regimen of Carboplatin and Vincristine. For those that do not know, these two drugs are a first line of defense in childhood tumors. They also carry with them the common side effects of chemo, including, in rare cases, hearing loss and possible secondary cancer. This is a benign grade 1 tumor, but it was large at the time of diagnosis. Due to the size and location, my oncologist does not want to use a "wait and see" approach. Considering the luck we had with the first surgery (no residual affects/up and walking the same day), my instinct is to pursue surgery, but that is against the wishes of the oncologist and surgeon. I absolutely hate the idea of giving my otherwise healthy kid a year's worth of chemotherapy. I'd really like to hear from someone who has gone through something similar. I'm interested in hearing from parents/patients that went through this regimen. I would also love to hear from those that have had aggressive surgery in the brainstem area and what the afteraffects are/were. Thanks in advance for your comments.