Prophylactic cranial irradiation in patients with small-cell lung cancer: the experience at the Institute of Oncology Ljubljana

BACKGROUND Prophylactic cranial irradiation (PCI) has been used in patients with small-cell lung cancer (SCLC) to reduce the incidence of brain metastases (BM) and thus increase overall survival. The aim of this retrospective study was to analyze the characteristics of patients with SCLC referred to the Institute of Oncology Ljubljana, their eligibility for PCI, patterns of dissemination, and survival. PATIENTS AND METHODS Medical charts of 357 patients with SCLC, referred to the Institute of Oncology Ljubljana between January 2004 and December 2006, were reviewed to determine characteristics of patients chosen for PCI. The following data were collected: age, gender, performance status (PS), extent of the disease, smoking status, type of primary treatment with outcome, haematological and biochemical parameters, PCI use, and finally brain metastases (BM) status at diagnoses and after treatment. RESULTS PCI was performed in 24 (6.7%) of all patients. Six (25%) patients developed brain metastases after they were treated with PCI. Brain was the only site of metastases in 4 patients, two progressed to multiple organs. Median overall survival of patients with PCI was 21.9 months, without PCI 12.13 months (p = 0.004). From the collected data there were good prognostic factors: age under 65 years, limited disease (LD), performance status, normal levels of lactate dehydrogenase (LDH) and normal levels of C-reactive protein levels (CRP). Other prognostic factors did not show statistical significant values. CONCLUSIONS Survival of patients with LD, who have had PCI, was significantly better than those who had not. We decided to perform PCI in patients with LD, in those with complete or near complete response, and those with good performance status (≥ 80). We did not use PCI in extended disease (ED). The reason for that shall be addressed in the future. Doses for PCI were not uniform, therefore more standard approach should be considered.