Colorectal cancer metastasis to the brainstem: A single case report.

Background: Colorectal cancer (CRC) is among the most widely prevalent malignancies afflicting increasingly high numbers of the population worldwide. Metastases majorly involve the liver and lungs but are not unheard of in the brain. Only one case has so far been reported to occur in the brainstem, excluding this one. Case Description: We report a second case of an 85-year-old male who presented with headaches and difficulty swallowing and was found to have a right anterior pontine lesion extending into the midbrain on magnetic resonance imaging of the brain and cecal adenocarcinoma on subsequent colonoscopy. The pontine lesion was biopsied and confirmed to be a metastatic lesion. He underwent a course of radiotherapy and tolerated it well, with improvement of his presenting symptoms. Conclusion: CRC-related morbidity and mortality are on the rise, as is expected with the incidence of metastases to the brain, including the brainstem, which is an extremely rare site for such metastases. This case illustrates such an encounter and the possibility of early detection of these metastases through brain imaging of patients with known or suspected CRC and symptoms of neurologic dysfunction. The current preferred management is surgical resection when possible, with or without radiotherapy. However, due to the rarity of the case, more data might be required to make more accurate decisions in these cases.