Prophylactic cranial irradiation

Prophylactic Cranial Irradiation

File:Brain CT scan.jpg

A CT scan of the brain, often used in the evaluation of patients undergoing PCI.

Prophylactic Cranial Irradiation (PCI) is a preventive medical procedure used primarily in patients with certain types of cancer, such as small cell lung cancer (SCLC), to reduce the risk of metastasis to the brain. PCI involves the administration of radiation therapy to the entire brain, even when there is no evidence of cancer spread to the brain at the time of treatment.

Indications

PCI is most commonly indicated in patients with SCLC who have achieved a complete or partial response to initial therapy. The rationale for PCI in these patients is based on the high incidence of brain metastases in SCLC and the poor prognosis associated with such metastases. By irradiating the brain prophylactically, the risk of developing brain metastases is significantly reduced, which can improve overall survival and quality of life.

Procedure

The procedure for PCI involves the use of external beam radiation therapy. Patients typically undergo a series of treatment sessions over several weeks. The total dose of radiation and the fractionation schedule can vary, but common regimens include 25 Gy delivered in 10 fractions.

During the procedure, patients are positioned on a treatment table, and a custom mask may be used to immobilize the head and ensure precise delivery of radiation. The radiation is delivered using a linear accelerator, and the entire brain is targeted.

Side Effects

While PCI can be effective in reducing the risk of brain metastases, it is associated with several potential side effects. Acute side effects may include fatigue, nausea, and headache. Long-term side effects can include cognitive decline, memory impairment, and other neurocognitive deficits. The risk of these side effects must be weighed against the potential benefits of the procedure.

Alternatives

Alternatives to PCI include regular magnetic resonance imaging (MRI) surveillance of the brain and treatment of brain metastases if and when they occur. This approach may be preferred in patients who are at higher risk for neurocognitive side effects or in those who decline PCI.

Related Pages

• Radiation therapy
• Small cell lung cancer
• Brain metastasis
• Cancer treatment