Colorectal cancer intracranial metastases treatment
see also Intracranial metastases treatment.
Current treatment options for brain metastases from CRC include surgical resection, whole-brain radiotherapy (WBRT), stereotactic radiotherapy (SRT), which includes stereotactic radiosurgery and fractionated stereotactic radiotherapy, and chemotherapy, alone or in combination. In general, surgical resection is performed for a single large (typically > 3 cm) brain metastasis with massive edema or when the metastasis is located in the eloquent area. Stereotactic radiosurgery using the Gamma Knife® or CyberKnife® is usually indicated for oligometastases of small sizes up to 3 cm. In fractionated stereotactic radiotherapy, which is typically performed for larger-sized brain metastases that cannot be handled by stereotactic radiosurgery, patients are treated with the CyberKnife® using a prescribed dose of 27–35 Gy delivered in 3–5 fractions in the tumor periphery. WBRT is selected for patients with multiple metastases or large-sized oligometastases with uncontrolled extracranial metastases, and/or those with poor performance status. Typical WBRT consists of 30 Gy in 10 fractions to the isocenter, delivered five times weekly with a linear accelerator 1).
The start of chemotherapy treatment usually requires a delay of about 4 weeks after surgical resection in patients with primary CRC having synchronous distant metastasis. However, there is no evidence to indicate the required length of this delay interval. In addition, there is a chance that a patient may die because postoperative chemotherapy was not started soon enough and a metastatic tumor was able to develop rapidly 2).