Radiographic and CT features of radiation-induced organizing pneumonia syndrome after breast-conserving therapy.

PURPOSE: To investigate radiographic and computed tomography features of radiation-induced organizing pneumonia syndrome after breast-conserving surgery. MATERIALS AND METHODS: The appearances and distribution of lung parenchymal abnormalities were retrospectively analyzed on chest radiographs (n = 12) and computed tomography scan images (n = 10) of 12 women (range 37-78 years, mean 55.8 years) with radiation-induced organizing pneumonia syndrome after breast-conserving surgery. RESULTS: The principal radiographic feature was an airspace filling pattern in all patients that involved the middle and lower lung zones in 10 of the 12 patients. Multi-focal lesions manifesting airspace consolidation surrounded by ground-glass opacities were the predominant CT finding in all 10 of these patients. The main lesion was predominantly located in the lung periphery in nine patients and contiguously extended to the central portion of the lung in seven patients. Frequent ancillary findings were airway dilation within the consolidation and lobar volume loss in nine and eight patients, respectively. All had solitary (6/10) or multifocal (4/10) distant lung opacities, mostly consistent with the finding of ground-glass opacities (9/10). Migration of the lung disease was observed in ten patients on subsequent radiographs. CONCLUSION: The cardinal radiologic feature of this syndrome is airspace consolidation surrounded by ground-glass opacification with airway dilation and volume loss, involving primarily the irradiated, subpleural area, along with distant opacities.

Evaluation of rectal bleeding factors associated with prostate brachytherapy.

PURPOSE: To analyze rectal bleeding prognostic factors associated with prostate brachytherapy (PB) or in combination with external-beam radiation therapy (EBRT) and to examine dosimetric indications associated with rectal bleeding. MATERIALS AND METHODS: The study included 296 patients followed up for >36 months (median, 48 months). PB was performed alone in 252 patients and in combination with EBRT in 44 patients. PB combined with EBRT is indicated for patients with a Gleason score >6. The prescribed dose was 144 Gy for monotherapy and 110 Gy for PB + EBRT (44-46 Gy). RESULTS: Although 9.1% who received monotherapy had 2.3% grade 2 rectal bleeding, 36.3% who received combined therapy had 15.9% grade 2 rectal bleeding. Combined therapy was associated with higher incidence of rectal bleeding (P = 0.0049) and higher percentage of grade 2 bleeding (P = 0.0005). Multivariate analysis revealed that R-150 was the only significant factor for rectal bleeding, and modified Radiation Therapy Oncology Group (RTOG) grade in monotherapy and biologically equivalent dose (BED) were significant for combined therapy. Moreover, grade 2 rectal bleeding increased significantly at D90 > 130 Gy. CONCLUSION: Although R-150 was the significant prognostic factor for rectal bleeding and modified RTOG rectal toxicity grade, BED was the significant prognostic factor for modified RTOG rectal toxicity grade.