Radiation-induced organizing pneumonia after stereotactic body radiotherapy for lung tumor

Abstract

The aim of this retrospective study was to investigate characteristics of organizing pneumonia (OP) after stereotactic body radiotherapy (SBRT) for lung tumor. Between September 2010 and June 2014, patients who were diagnosed as Stage I lung cancer and treated with SBRT at our institution were included in this study. A total of 78 patients (47 males with a median age of 80 years) were analyzed. The median follow-up period was 23 months. Five patients (6.4%) developed OP at 6–18 months after SBRT. The cumulative incidence of OP was 4.3% (95% confidence interval [CI], 1.1–11.0) and 8.2% (95% CI, 2.9–17.0) at 1 and 2 years, respectively. Tumor location (superior and middle lobe vs inferior lobe) was shown to be a borderline significant factor for the occurrence of OP (P = 0.069). In the subgroup analysis of patients with a radiographic follow-up period at least 6 months, or who died within 6 months after SBRT, 7 of 72 patients (9.7%) developed Grade 2 or 3 radiation pneumonitis (G2/3 RP) at 2–4 months after SBRT. A statistically significant association between G2/3 RP in the subacute phase and OP was shown (P = 0.040). In two of the five patients who developed OP, the symptoms and radiographic change were improved rapidly by corticosteroid administration. One patient had relapsed OP after suspending the treatment and re-administration was required. Three patients with minor symptoms were managed without corticosteroid administration and OP resolved without any relapse. The radiation-induced OP should be considered as one of the late lung injuries after SBRT for lung tumors.

Irradiation enhanced risks of hospitalised pneumonopathy in lung cancer patients: a population-based surgical cohort study

“…In irradiated lung cancer patients, radiotherapy has been reported to increase incidences of pneumonopathy, including infectious 5 and non-infectious pneumonia, 7 as well as pneumonitis. 11 A common feature exists among these types of pneumonopathy.…”

“…Three reasons supported this hypothesis. First, several lines of evidence have been reported to support that irradiation may induce several forms of pathological pneumonopathy, such as post-irradiation organising pneumonia, 7 8 acute pneumonitis and/or late fibrosis. 28 34 59–61 These irradiation-induced pathological changes are able to damage resident lung cells, to disrupt local barriers and to disturb local immune of the irradiated lung.…”

“… 1–3 Radiotherapy is one of the major treatment modalities in managing lung cancer patients. 4 However, irradiation has been reported to correlate with an increased incidence of several types of pneumonopathy, such as infectious pneumonia, 5 6 non-infectious organic pneumonia 7–10 and radiation pneumonitis, 11–13 even after a 2-year follow-up period. 14 …”

The impact of emphysema on dosimetric parameters for stereotactic body radiotherapy of the lung

“…Our methods for treatment planning have previously been described in detail [ 11 , 12 ]. SBRT plans were generated using the Pinnacle planning system (Phillips Medical System, Andover, MA).…”

Increased neutrophils and IL-17A in a rare organizing pneumonia secondary to extrapulmonary operation

“…When the lung is injured by various acute and chronic factors, it can be manifested as diffuse alveolar damage, OP, acute fibrinous and OP and certain types of fibrotic lung disease (2) In 2001, the American Thoracic Society and the European Respiratory Society (ATS/ERS) referred to idiopathic OP as cryptogenic pneumonia (COP), which is recognized as a subtype of idiopathic interstitial pneumonia and OP with specific etiology as secondary organizing pneumonia (SOP) (3). As we know, a number of diseases and factors are correlated with OP, such as infection (4), connective tissue disease (CTD) (5,6), radiation therapy (7), drug reaction (8), cancer (9), hematological diseases (10), inflammatory bowel disease (11), organ transplantation (12), gastroesophageal reflux disease (13), toxic exposure (14), thyroid disease (15), and menstruation (16). In recent years, some cases of OP following chest surgery have also been reported (17).…”