Prophylactic cranial irradiation in small cell lung cancer: A single-center experience.

Objective: Small-Cell Lung Cancer (SCLC) constitutes about 15% of all lung cancers. It tends to frequently metastasize to the brain. Prophylactic Cranial Irradiation (PCI) is performed, when the penetration of chemotherapeutic agents to brain is insufficient. The aim of this study was to report our single-center experience with PCI in SCLC cases. Methods: We retrospectively reviewed 28 patients with SCLC diagnosed between March 2007 and November 2016. Cranial Computed Tomography (CT) or Magnetic Resonance Imaging (MRI) was performed from all patients to exclude metastasis before PCI. Radiation Therapy (RT) was conducted using two different instruments: a three-dimensional conformal RT-based Linear Accelerator (LINAC) instrument was used until 2013 and an Intensity-Modulated Radiation Therapy (IMRT) thereafter. All patients were treated with a total of 25-36 Gy with fraction doses of 2-2.5 Gy. Overall survival was estimated in all patients. Results: The mean age was 56 (range: 36 to 72) y. Only one of the patients was female, while the remaining patients were all males. Twenty two patients (78.5%) were in limited stage SCLC, while six patients (21.5%) were in the extensive stage. Seventeen patients died, while 11 of them survived. The mean survival was 35 months, while it was 40 months for limited stage and 17 months for extensive stage (p=0.027). One, two, and five-year OS rates were 81.4%, 58%, and 17%, respectively. Four (14%) patients developed brain metastasis during follow-up. Of these patients, two were treated with Whole Brain RT (WBRT), one with Stereotactic RT (SBRT), and the other with best supportive care. Conclusion: Our study results suggest that PCI is a safe, low-toxicity treatment modality used to prevent brain metastases in SCLC cases.