Introduction
Colorectal cancer is the third most common cancer and the fourth leading cause of cancer-related deaths in the world. Men are more frequently affected, and 25% of patients present with distant metastases on diagnosis, and 25% suffer metastases further on. Metastatic disease usually develops liver or lung metastases. Brain metastases (BM) for this type of cancer are rare and optimal treatment remains undefined, we present an uncommon case of colon cancer metastasized to brain which was treated with stereotactic surgery.

Case description
62-year-old male with past medical history of hypertension, chronic kidney disease, hemorrhagic stroke, colon cancer T4aN1bM0 (status post extended left hemicolectomy and 12 cycles of FOLFOX chemotherapy) diagnosed one year prior to admission presented to the emergency department with complaints headache and back after a fall on his back, with head trauma. He reported a sensation of lightheadedness that made him lose balance, no palpitations, no loss of consciousness, no nausea or vomiting, no visual or sensory changes. Vital signs with BP of 166/76 rest within normal limit. CT Brain noted a 1.7 x 1.5cm hypodense mass with calcifications related to the region of the right external capsule with adjacent vasogenic edema. CT lumbar spine with mild acute compression fracture superior endplate L2 vertebral body without retropulsion. Patient was admitted for brain mass. Further workup with MRI showed 18 x 15 mm right lateral inferior deep frontal lobe and sub insular region in homogeneous enhancing mass, surrounded by edema with some mild regional mass effect, which was consistent with metastatic lesions. Patient was evaluated by neurosurgery, however, did not require any intervention. He was evaluated by radio/oncology and oncology and underwent stereotactic radiosurgery without complications. Patient would follow up as outpatient for PET /CT and continuity of treatment.

Discussion
The incidence of BM ranges from 0.6-4.2% usually occurring in advanced stages of disease and is common to be concomitant with liver or lung metastasis as well. Clinical presentation can range from asymptomatic to seizures and focal neurological signs. In our case, it is uncertain whether the lightheadedness and fall were related to the BM. The prognosis of colorectal cancer metastatic to the brain is poor with a median survival of 4-6 weeks for untreated ones and 6-9 months in active treatment. Local treatment approaches include neurosurgical resection, whole-brain radiation therapy, stereotactic radiosurgery, and hypofractionated stereotactic radiosurgery. The choice is determined by disease, patient performance status, site, and size of metastasis, however, there is limited data on the optimal treatment for these patients.

Conclusion
Colorectal cancer with brain metastases is a rare occurrence that is related to poor prognosis. Multiple treatment options exist, however, data on long-term prognosis is limited; more research is needed to create guidelines for it.

References and Resources

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