Obesity Increases the Risk of Chest Wall Pain From Thoracic Stereotactic Body Radiation Therapy

Abstract

Purpose Stereotactic body radiation therapy (SBRT) is increasingly being used to treat thoracic tumors. We sought here to identify dose-volume parameters that predict chest wall toxicity (pain and skin reactions) in patients receiving thoracic SBRT. Methods We screened a database of patients treated with SBRT between August 2004 and August 2008 to find patients with pulmonary tumors within 2.5 cm of the chest wall. All patients received a total dose of 50 Gy in four daily 12.5-Gy fractions. Toxicity was scored according to the NCI-CTCAE V3.0. Results Of 360 patients in the database, 265 (268 tumors) had tumors within <2.5 cm of the chest wall; 104 (39%) developed skin toxicity (any grade); 14 (5%) developed acute pain (any grade), and 45 (17%) developed chronic pain (grade 1 in 22 cases [49%] and grade 2 or 3 in 23 cases [51%]). Both skin toxicity and chest wall pain were associated with the V30 or volume of the chest wall receiving 30Gy. Body mass index (BMI) was also strongly associated with the development of chest pain: patients with BMI ≥ 29 had almost twice the risk of chronic pain (P = 0.03). Among patients with BMI over 29, diabetes mellitus was a significant contributing factor to the development of chest pain. Conclusion Safe use of SBRT with 50 Gy in 4 fractions for lesions close to the chest wall requires consideration of the chest wall volume receiving 30 Gy and the patient’s BMI and diabetic state.

Dosemetric Parameters Predictive of Rib Fractures after Proton Beam Therapy for Early-Stage Lung Cancer

“…In our study, grade 2 RFs occurred in 12 patients following PBT (19.4%), with a three-year cumulative incidence rate of 30.2%. With regard to SRT, several groups reported RFs frequencies ranging from 4% to 37.7% after SRT for earlystage NSCLC; these rates were not much higher compared with those observed in our study (30.2%) (Pettersson et al 2009;Dunlap et al 2010;Andolino et al 2011;Welsh et al 2011;Asai et al 2012;Creach et al 2012;Mutter et al 2012;Stephans et al 2012;Taremi et al 2012;Nambu et al 2013). Although PBT reportedly offers advantages over SRT, it has not been reported to dramatically reduce RFs incidence (Georg et al 2008;Kadoya et al 2011).…”

“…However, desired dose applications within target volumes are limited because of the proximity to critical normal tissues. Also, the incidence of rib fractures (RFs) following SRT for early-stage lung cancer ranges from 4% to 37.7% (Pettersson et al 2009;Dunlap et al 2010;Andolino et al 2011;Welsh et al 2011;Asai et al 2012;Creach et al 2012;Mutter et al 2012;Stephans et al 2012;Taremi et al 2012;Nambu et al 2013).…”

Lung stereotactic ablative radiotherapy (SABR): dosimetric considerations for chest wall toxicity

“…5,11,16 In this present study, 20 patients had chest wall pain of $Grade 2 after a median of 9 months (range: 0-24 months). This is in keeping with existing data such as that reported by Andolino et al 11 [median time to chest wall toxicity 9 months (range: 1-50) months] and Welsh et al 16 [median time to chest wall pain 6 months (range: 0-11 months)].…”

“…11,16 Symptoms may develop without obvious injury or may result from rib fracture, nerve damage or skin reaction (erythema, ulceration and fibrosis). 5,[8][9][10] Equally, rib fractures may occur in association with SABR but without symptoms.…”

“…9,16,26 Our study is limited in that we did not have sufficient information to include these in the analysis, and it may be that the addition of these factors would improve the goodness of fit and utility of our model. Indeed, Woody et al 26 produced a multivariate model which included dosimetric information (modified equivalent uniform dose) and body mass index.…”