Impact of Pretreatment Weight Loss on Radiotherapy Utilization and Clinical Outcomes in Non-Small Cell Lung Cancer.

BACKGROUND: Cancer cachexia is a syndrome of unintentional weight loss resulting in progressive functional impairment. Knowledge of radiation therapy utilization in patients with cancer cachexia is limited. We evaluated the use of curative and palliative-intent radiation for the management of patients with non-small cell lung cancer (NSCLC) with cachexia to determine whether tumor-directed therapy affected cachexia-associated outcomes. METHODS: Using an Institutional Tumor Registry, we evaluated all patients with stages of NSCLC treated at a tertiary care system from 2006 to 2013. We adopted the international consensus definition for cachexia, with staging designated by the registry and positron emission tomography. Radiotherapy delivery and intent were retrospectively assessed. RESULTS: In total, 1330 patients with NSCLC were analyzed. Curative-intent radiotherapy was utilized equally between patients with cachexia and non-cachexia with stages I to III NSCLC. Conversely, significantly more patients with stage IV disease and cachexia received palliative radiotherapy versus those without (74% vs 63%, P = 0.006). Cachexia-associated survival was unchanged irrespective of tumor-directed radiation therapy with curative or palliative intent. In fact, pretreatment cachexia was associated with reduced survival for patients with stage III NSCLC receiving curative-intent radiotherapy (median survival = 23.9 vs 15.0 mo, P = 0.009). Finally, multivariate analysis identified pretreatment cachexia as an independent variable associated with worsened survival (hazard ratio = 1.31, CI: 1.14,1.52). CONCLUSION: Patients with advanced NSCLC with cachexia received more palliative-intent radiation than those without weight loss. Tumor-directed therapy in either a curative or palliative approach failed to alter cachexia patient survival across all stages of the disease. These findings offer critical information on the appropriate utilization of radiation in the management of patients with NSCLC with cachexia.