CT findings of acute radiation-induced pneumonitis in breast cancer

Abstract

Objectives: To evaluate the computed tomography (CT) findings of acute radiation pneumonitis (RP) in breast cancer patients undergoing postoperative radiotherapy, and to analyze clinico-dosimetric factors associated with acute RP. Methods: Between 2015 and 2017, 61 patients with breast cancer who underwent follow-up chest CT at 3 months after radiotherapy were analyzed. The degree of acute RP on CT was evaluated by the change of extent and scoring system (grade 0, no RP; Grade 1, ground-glass opacities (GGOs); Grade 2, GGOs and/or consolidations; Grade 3, clear focal consolidation; Grade 4, dense consolidation). The dosimetric parameters were calculated from the dose-volume histogram of RT. Results: The acute RP on CT was scored as follows: grade 0, in 37.7%, Grade 1 in 13.1%, Grade 2 in 44.3%, and Grade 3 in 4.9%. The median extent of RP in patients with Grades 1 to 3 was 6.2 ml (range, 0.2–95.9). There were no clinico-dosimetric factors significantly associated with the presence of RP or its severity. One patient developed symptomatic RP. Conclusions: This study showed no correlation between acute RP and clinico-dosimetric factors, and acute RP based on CT findings were much more common than symptomatic RP. Advances in knowledge: CT findings of acute RP or extent of RP were not significantly related to clinico-dosimetric factors in breast cancer patients.

Systematic risk analysis of radiation pneumonitis in breast cancer: role of cotreatment with chemo-, endocrine, and targeted therapy

“…As expected, the risk of RP increased significantly when lymph node irradiation was indicated, expressed as symptomatic RP incidences increased by a factor of 1.6 (PCN inclusion) and 2.6 (PCN + IMN inclusion). Due to the applied moderately higher dose concepts used during the study, the observed overall RP incidence was higher than reported for comparable patient cohorts, especially as IMRT/VMAT is commonly performed nowadays [ 38 – 42 ]. However, in our cohort, all 40 patients with diagnosed RP ≤ grade II exhibited moderate symptoms, and all of them recovered completely within a median time of 9 months (range 1 to 24 months).…”