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

Abstract

Purpose A major complication of sequential and concomitant chemoradiation in breast cancer treatment is interstitial pneumonitis induced by radiation therapy (RT), systemic therapy, or a combination of both. Dose and volume of co-irradiated lung tissue directly correlate with the risk of radiation pneumonitis. Especially in case of combined treatment, it is often unclear which of the used therapeutic agents promote pneumonitis. Methods This was a prospective monocentric study including 396 breast cancer patients. A systematic analysis of single and combined therapeutic measures was performed in order to identify treatment-related factors enhancing the risk of pneumonitis post RT. Results Overall incidence of pneumonitis of any grade was 38%; 28% were asymptomatic (grade 1) and 10% were symptomatic (> grade 1). Pneumonitis > grade 2 did not occur. Beside age, smoking status, and mean lung dose, the combined treatment with goserelin and tamoxifen significantly enhanced the risk of pneumonitis in a supra-additive pattern (odds ratio [OR] 4.38), whereas each agent alone or combined with other drugs only nonsignificantly contributed to a higher pneumonitis incidence post RT (OR 1.52 and OR 1.16, respectively). None of the other systemic treatments, including taxanes, increased radiation pneumonitis risk in sequential chemoradiation. Conclusion Common treatment schedules in sequential chemoradiation following breast-conserving surgery only moderately increase lung toxicity, mainly as an asymptomatic complication, or to a minor extent, as transient pneumonitis ≤ grade 2. However, combined treatment with tamoxifen and the LHRH analog goserelin significantly increased the risk of pneumonitis in breast cancer patients after chemoradiation. Thus, closer surveillance of involved patients is advisable.

Does shortening the duration of radiotherapy treatment in breast cancer increase the risk of radiation pneumonia: A retrospective study

“…There is a difference in the incidence of RP between standard 3DCRT and IMRT. [21,22] MLD has been identified as the most reliable predictor of RP risk after breast cancer RT, and the incidence of RP increases significantly when MLD values are above 10 Gy. [23] Oetzel et al conducted a study to determine the relationship between radiation dose and the risk of lung damage.…”

Radiation therapy of breast cancer in the Nahe Breast Center: first results of an analysis in the context of health services research

“…Pulmonary toxicity is slightly better, but only grade 1 symptomatic pneumonitis was reported in our study. Asymptomatic pneumonitis was not analyzed [ 14 , 15 ].…”

Radiotherapy dosimetry and radiotherapy related complications of immediate implant-based reconstruction after breast cancer surgery

“…Most RP were mild and moderate. In a study carried out by MangesiusJ including 396 breast cancer patients, the total incidence of RP was 38%, of which 10% were symptomatic (> grade 1) ( 24 ). The improved dose homogeneity achieved with IMRT may have explained the low RP rates in our study.…”