Background: Radiation therapy plays an important role for symptom palliation for intrathoracic malignancies ineligible for curative-intent therapy. Limited data exists regarding the role of stereotactic body radiation therapy (SBRT) versus conformal radiation in intrathoracic tumors for palliation. We report the efficacy of hypofractionated RT (or palliative SBRT) in the symptom management and durable control of lung and non-lung intrathoracic tumors.
Methods: We performed a retrospective review of ninety-two thoracic lesions across 76 patients who completed palliative SBRT with doses ranging 25-50 Gy in 5-10 fractions between 2009 and 2019. Symptoms (cough, chest pain, hemoptysis, shortness of breath) were assessed at consult and 1-6 months follow-up. Local control was evaluated using follow-up CT imaging via RECIST criteria. Descriptive statistics were used to evaluate symptom palliation and Kaplan-Meier method to analyze local control.
Results: Of primary lung (Cohort P) lesions, 40% showed stable symptoms, 30% never developed symptoms, and 19% showed symptom relief. CT imaging 1-6 months post-SBRT showed 91% with partial response (PR) or stable disease (SD) in Cohort P and 87% with PR or SD in metastatic (Cohort M) lesions. In patients with initial PR/SD, local control until death was achieved in 71% of Cohort P and 84% of Cohort M. Of our symptomatic patients (Cohort S), 98% showed no symptom progression post-radiotherapy. All patients with hemoptysis at presentation achieved hemostasis post-radiotherapy.
Conclusions: Palliative SBRT has the advantage of higher biologic dose without protracted course for patients with limited prognosis. Patients showed significant symptom palliation and long-term local control. Palliative SBRT represents a reasonable treatment modality for incurable thoracic malignancies.
Keywords: Palliative radiotherapy; hypofractionated; radiation oncology; stereotactic; thoracic cancers.