Brain radiation therapy complication (radionecrosis) potentially linked to combined chemo-immunotherapy

What happened, in summary

A woman in her 60s had been living with Stage IV non-small cell lung cancer for about 3 years. At diagnosis, the cancer involved lymph nodes and the liver, but brain imaging was clear. She first received carboplatin, pemetrexed and pembrolizumab, followed by maintenance treatment. Pemetrexed was later stopped because of severe neuropathy, while pembrolizumab continued for 2 years.

Three months after pembrolizumab ended, imaging showed brain metastases and possible spread along the lining of the brain. She received whole-brain radiation in 10 treatments. Later systemic therapy included docetaxel with ramucirumab, dose-reduced gemcitabine and nivolumab.

Eleven months after whole-brain radiation, MRI showed a new abnormal area in the right temporal lobe. At first she had mainly poor balance, but within 3 weeks she developed worsening right-sided headache, blurred vision and weakness on the left side. The scan could not reliably distinguish active cancer from delayed radiation injury, so she underwent a right temporal craniotomy and removal of the lesion.

Pathology found damaged and necrotic brain tissue without cancer, confirming radiation necrosis. After surgery, she made a complete neurological recovery and had no residual deficits. Combination cancer treatment was resumed, and she remained neurologically intact 18 months after the operation.

Nine months after that last follow-up, she was found to have died. The cause of death was not established. Her course therefore included successful treatment of symptomatic radiation necrosis, followed by later death in the setting of metastatic lung cancer.