Updated: Jan 22, 2020
David and I met with Dr. Sipos (neurosurgeon) on 1/3 and with Dr. Frye (radiology oncologist) on 1/7. Both said the three new tumors are small and can be treated with pinpoint radiation the way the three original tumors were treated. In the coming days (probably the week of 1/13), David will get a high-resolution MRI and, if needed, have a new mask made. (Because the steroids caused David to gain weight in his face, David's previous mask might not fit well enough.) Then (probably the week of 1/20), David will receive the radiation, which will entail two appointments rather than one long appointment so David doesn't need to endure wearing the mask and lying on a hard table for so long.
Both doctors said they expect David to fully recover from these tumors, and Dr. Frye mentioned that the cerebellum, which is the area where the largest of the original tumors exists, is very plastic and can grow new connections to compensate for damage caused by the tumor. They also said that tumor, which has so far shrunk only about 40%, should continue to shrink and not require further radiation. All this is good news. An additional piece of good news is that David won't need to take steroids again, because the new tumors aren't causing much inflammation.
David aced his neurological exams with both doctors, and he continues to go to PT twice a week to improve his balance and muscle strength.
As for what lies ahead, it's possible more brain tumors will show up on future MRIs, but because MRIs will be done every two or three months, any new tumors should be caught when they are small and as long as there aren't a large number at the same time and no tumors develop in the lining of the brain, they should be treatable with pinpoint radiation. So, the situation that seemed very bleak last week is looking much better now.