Upright versus supine positioning for breast and lung radiotherapy: a pilot study on patient comfort, experience and lung function.

Delivering radiotherapy in upright body positions (UP) may offer advantages for breast and lung cancer treatments due to physiological/anatomical differences compared to the supine position (SP), as well as potential cost savings when establishing new treatment rooms. This pilot study compared (i) patient experiences and (ii) lung function parameters for upright UP versus SP, among a cohort of patients undergoing conventional (supine) radiotherapy for breast or lung cancer. After ethical approval, 8 breast and 7 lung cancer patients were enrolled in this study. Five research appointments were conducted for each patient. Patients were set-up with UP and SP with their arms raised out of the thoracic region. Through questionnaires, patients reported on any discomfort, their general experiences and their preferred setup. Spirometry-based measurements taken included the tidal Volume (Vt), Vital Capacity (VC), and maximum duration of Deep Inspiration Breath Holding (DIBH). Expiratory Reserve Volume (ERV), Inspiratory Capacity (IC) were calculated. Discomfort was most frequently reported in the lower back during SP and in the knees during UP. Nine patients preferred UP for physical comfort and 8 preferred UP for DIBH whereas 1 and 6 preferred SP respectively. Patients described significantly less pain when they stood up after the UP than after SP. In UP, ERV was significantly larger (p < 0.05), while Vt and IC were significantly smaller (p > 0.05) compared to UP. There was no difference in VC between the two positions (p = 0.17). The majority of patients preferred UP and reported being more comfortable in UP in comparison to SP. Overall, body position influences Vt, ERV and IC but no differences were observed in VC, consistent with the literature. DIBH was feasible for all patients in both positions.