Re-irradiation for metastatic brain tumors with whole-brain radiotherapy.

OBJECTIVE: To determine whether second whole-brain irradiation is beneficial for patients previously treated with whole-brain irradiation. METHODS: A retrospective analysis was done for 31 patients with brain metastases who had undergone re-irradiation. Initial whole-brain irradiation was performed with 30 Gy/10 fractions for 87% of these patients. Whole-brain re-irradiation was performed with 30 Gy/10 fractions for 42% of these patients (3-40 Gy/1-20 fractions). Three patients underwent a third whole-brain irradiation. RESULTS: The median interval between the initial irradiation and re-irradiation was 10 months (range: 2-69 months). The median survival time after re-irradiation was 4 months (range: 1-21 months). The symptomatic improvement rate after re-irradiation was 68%, and the partial and complete tumor response rate was 55%. Fifty-two percent of the patients developed Grade 1 acute reactions. On magnetic resonance imaging, brain atrophy was observed in 36% of these patients after the initial irradiation and 74% after re-irradiation. Grade ≥2 encephalopathy or cognitive disturbance was observed in 10 patients (32%) after re-irradiation. Based on univariate analysis, significant factors related to survival after re-irradiation were the location of the primary cancer (P = 0.003) and the Karnofsky performance status at the time of re-irradiation (P = 0.008). A Karnofsky performance status ≥70 was significant based on multivariate analysis (P = 0.050). CONCLUSIONS: Whole-brain re-irradiation for brain metastases placed only a slight burden on patients and was effective for symptomatic improvement. However, their remaining survival time was limited and the incidence of cognitive disturbance was rather high.

Definitive chemoradiotherapy of limited-disease small cell lung cancer: Retrospective analysis of new predictive factors affecting treatment results.

The aim of this study was to evaluate potential predictive factors in the treatment of limited-disease small cell lung cancer (LD-SCLC). A total of 33 patients with LD-SCLC who underwent definitive chemoradiotherapy at our institute between April 1996 and May 2007 were enrolled in our retrospective study. The relationship between a range of potential predictive factors and the initial response, time to progression and pattern of failure was analyzed. The factors evaluated included the tumor markers Pro-gastrin-releasing peptide (Pro-GRP) and neuron-specific enolase; net tumor size (sum of each lesion mass on computed tomography at 1-cm intervals); total radiation dose; biological effective dose (BED); overall treatment time (OTT); time between the start of any type of treatment and the end of radiation therapy (SER). In addition, the novel factors of radiation dose-intensity (RDI = BED/OTT) and RDI/NTS (= RDI/net tumor size) were defined. Of the 33 patients evaluated in our study, 22 (67%) achieved a complete response (CR) and 27 (82%) experienced treatment failure or recurrence. High RDI/NTS values showed a significant correlation with CR (P=0.043). Prolonged OTT and lower values of RDI and RDI/NTS showed a significant correlation with recurrence within 12 months (P=0.022, 0.033 and 0.015, respectively). The lower values of RDI and RDI/NTS showed a significant correlation with distant metastasis as a first failure site (P=0.038 and 0.044, respectively). Patients with RDI/NTS ≥0.08 had a more favorable prognosis (P=0.045). Thus, RDI and RDI/NTS may become beneficial predictive factors in the treatment of LD-SCLC. However, further studies are required to confirm our preliminary results.