Re-irradiation for locoregionally recurrent tumors of the thorax: a single-institution, retrospective study.

BACKGROUND: Re-irradiation (re-RT) of the thorax is challenging due to the impact of prior therapies on normal tissues, and there are few reports of definitive re-RT. The treatment toxicities and efficacy of re-RT are not well known. The aim of the present study was to assess the safety and efficacy of definitive re-RT of the thorax. METHODS: Patients who were treated with thoracic re-RT between March 2007 and December 2014 were retrospectively analyzed. Primary and re-irradiation plans were required to have an overlap of dose distributions for the 80 % isodose level. All doses were recalculated to an equivalent dose of 2 Gy per fraction (EQD2). When possible, analysis of dose accumulation was carried out using the medical image merge (MIM) (®) software program (version 6.5, MIM Software Inc., Cleveland, OH). Administration dosages for organs at risk were defined. RESULTS: Fourteen (67 %) and seven (33 %) patients with non-small cell carcinoma (NSCLC) and small cell carcinoma (SCLC), respectively, were identified. The patients' median age was 72 (range 53-85) years. Fifteen patients (71 %) had "proximal" tumors, defined as tumors at the distal 2 cm of the trachea, carina, and main bronchi. The median interval from initial RT to re-RT was 26.8 (range 11.4-92.3) months. Re-RT was delivered by X-ray beam and proton beam therapy in 20 (95 %) patients and 1 (5 %) patient, respectively. The median radiation dose of re-RT was 60 (range 54-87.5) Gy10 and 50 (range 50.0-87.5) Gy10 for patients with NSCLC and SCLC, respectively. Grade 3 acute radiation pneumonitis occurred in only one patient. There were no other serious complications. The median follow-up time was 22.1 (range 2.3-56.4) months. The median local progression-free survival time (LPFS) and overall survival time (OS) were 12.9 (95 % confidence interval (CI): 8.9-27.9) months and 31.4 (95 % CI: 16.9-45.9) months, respectively. Patients receiving ≥ 60 Gy10 at re-RT had longer LPFS (p = 0.04). CONCLUSIONS: Good safety with longer OS than in previous reports was demonstrated. Re-RT seems to be a promising treatment option. Further study to define the risk-benefit ratios is necessary.

Comparison of the efficacy of radiotherapy between postoperative mediastinal lymph node recurrence and stage III disease in non-small cell lung cancer patients.

PURPOSE: It is unknown if local treatment is equally effective in non-small cell lung cancer (NSCLC) patients with postoperative mediastinal lymph node recurrence or primary stage III disease. The purpose of this study was to investigate the effectiveness of radiotherapy, with or without chemotherapy, in patients with postoperative mediastinal lymph node recurrence. METHODS: Patient characteristics, treatment response and survival were compared between NSCLC patients with mediastinal lymph node metastases treated between 2002-2009 by radiotherapy alone or by chemoradiotherapy (group A, N=33) and those with primary stage III disease (group B, N = 157). RESULTS: Men accounted for 60.6% of group A and 78.9% of group B (p=0.04 patients). ECOG performance status 0 was detected in 78.7% of group A and 57.3% of group B (p=0.02). The response rates in groups A and B were 66.6 and 72.3%, respectively (p=0.64). Progression-free survival (PFS) was similar between groups A and B (median 15.0 vs 11.0 months; hazard ratio [HR] 0.78; 95% CI 0.51-1.20; p=0.26). However, overall survival (OS) was better in group A than in group B (median 67.0 vs 39.0 months; HR 0.56; 95% CI 0.29-0.97; p=0.03). Postoperative PFS (median 12.5 vs 19.0 months; HR 1.50; 95% CI 0.64-3.49; p=0.34) and OS (median, 67.0 vs 60.0 months; HR 1.22; 95% CI 0.36-4.14; p=0.74) were similar between the group A treatments (radiotherapy and chemoradiotherapy, respectively). CONCLUSION: Postoperative mediastinal lymph node recurrent NSCLC demonstrated distinctive features including better OS compared to patients with primary stage III disease, despite similar response rates and PFS.

Reirradiation of spinal metastases with intensity-modulated radiation therapy: an analysis of 23 patients.

This study aimed to evaluate the efficacy and safety of reirradiation with intensity-modulated radiation therapy (IMRT) for spinal metastases. We retrospectively analyzed 23 patients with spinal metastases who underwent IMRT reirradiation between December 2006 and July 2013. We evaluated the spinal radiation doses during the first and second radiation therapy courses, the interval between the courses, and the clinical outcomes after reirradiation, including skeletal-related events, local control rates (LCRs), overall survival (OS), and toxicities. The median time from the first irradiation to reirradiation was 13 months (range, 2-75 months). The median reirradiation dose delivered to 90% of the planning target volume was 24.5 Gy in 5 fractions (range, 14.7-50 Gy in 3-25 fractions). Nineteen patients experienced pain at reirradiation, and 15 of these attained pain relief. Two of the three patients with paresis in the upper or lower extremities upon initiation of reirradiation demonstrated improvement. Local progression was identified in four patients. The median time to local progression was 37 months. The 1- and 2-year LCRs after reirradiation were 88% and 75%, respectively. The 1- and 2-year OS rates after reirradiation were 45% and 20%, respectively, with a median OS of 12 months. No late toxicities occurred. In conclusion, spinal metastasis reirradiation using IMRT appears safe; pain relief and paresis improvement and/or prevention can be expected, along with a reduced risk of radiation-induced toxicity, especially in the spinal cord.