Impact of body morphology on survival in patients with bone metastases: A prospective cohort study

Purpose or Objective High-precision stereotactic body radiotherapy (SBRT) has proven to be a valuable method in the curative and palliative treatment of different tumor entities and is meanwhile an established keystone in the field of neoadjuvant tumor-therapy. In this study, we evaluate the effect of SBRT in patients with metastases in the adrenal gland focused on progressfree-survival (PFS), overall survival (OS), and acute as well as late toxicity. Material and Methods A cohort of 24 patients was analyzed treated with SBRT for metastases in the adrenal gland between 2006 and 2018. Treatment-planning was performed through contrast-enhanced CT followed by the image-guided radiation therapy (IGRT) using Cone-beam-CT (CBCT). SBRT was applied with a cumulative median dose of 35 Gy (range: 25-40 Gy) and a single dose of 5 Gy in five fractions per week. Results The evaluation is still ongoing. Primary tumors of the patients were: NSCLC 45.8 %, Mamma-Ca 12.5 %, Melanoma 12.5 %, Sarcoma 8.3 %, and others 20.9 %. At the time of analysis, 7 patients (29.2 %) experienced local failure (LF) of the neoplasia in the adrenal gland (mean LF: 52.0 months, 95%-KI: 26.2-77.8 months, median not reached), 19 (79.2 %) faced a distant progression (medianPFS: 2.2 months, 95%-KI: 1.8-2.6 months). 12 patients were still alive (50 %), 5 of them without LF (41.7 %), 4 of them (33.3 %) without any tumor progression (median OS: 12.9 months, 95%-KI: 6.3-19.5 months). Our results showed that there occurred no treatmentrelated side-effects ≥ grade 2, which reflects the overall low-grade-toxicity of SBRT used for adrenal-glandmetastases. Toxicity rates ≥ grade 2 were as follows: 41.7 % suffered from acute (<= 6 months) gastrointestinal disorders like nausea (29.2 %), vomiting (8.3%), and abdominal pain (4.2 %); 29.2 % also reported acute fatigue, constipation, throbbing pain in the renal area and increase of the retention parameters. Only 20.8 % of the patients faced late-toxicities like loss of weight (4.2 %), fatigue (4.2 %) and gastrointestinal medical conditions (12.5 %) persisting or appearing after the 6-month-period. Conclusion SBRT is a safe and effective method for treating metastases in the adrenal gland. None of the patients had treatment-related acute or late toxicities ≥ grade 2, and 70.8% of the patients were progression-free after RT.