Purpose/Objective(s): Limited data exist on the outcomes of patients treated with hypofractionated image-guided radiation therapy (HIGRT) for patients with adrenal oligometastases (OM). Therefore, we report our experience with such patients treated at the University of Chicago.Methods/Materials: A database of OM (≤5 sites) patients consecutively treated with HIGRT was reviewed. Patients receiving HIGRT to adrenal metastases were analyzed. All metastatic sites were treated with HIGRT either on a three-fraction (fxn) dose-escalation protocol [(8-14 Gy/fxn) or with 10 fxn[4-5 Gy/fxn]. The median biologic effective dose (BED) was 60 Gy (range: 43.2 -79.2 Gy). The PTV expansion was 5-10 mm on gross disease. CT+/-PET scans were obtained prior to HIGRT and during follow-up. Response to HIGRT was determined by RECIST (response evaluation criteria in solid tumors) criteria or metabolic CR on PET. The ultimate endpoints were local control, distant control, and overall survival.Results: From 2005-2009, ten patients with 13 adrenal metastases were identified. The primary tumor sites were lung (n = 8) and renal (n=2). Eight of the ten patients were treated with prior chemotherapy with a median of 3 agents. The median follow-up was 14.6 months (range: 5.0-45.8 mos). The median treated metastasis size was 4.1 cm (range: 2.1-7.7 cm) with a median volume of 19.2 cc (range: 6.4-131cc). Treatment was generally well tolerated. One patient experienced grade 2 nausea and no patients developed grade 3 or 4 toxicity. The initial response was PR in 4 patients and SD in 9. Ten metastases (77%) were controlled at last follow-up. The 1 yr actuarial treated metastasis control rate was 78%. Progression in treated metastases occurred in those treated with the lowest protocol dose of 8 Gy x 3 (BED=43.2) at a median of 6.5 mos from the completion of therapy. Two failures occurred in one patient with NSCLC and one failure was in a patient with SCLC. The volume of failed lesions was: 6.4, 19.2, and 24.3cc. The 1 yr distant progression-free survival rate was 30%. The median overall survival was 17.4 months (1 yr OS=90%, 2 yr OS=48%). At time of failure, 7 patients progressed with <=5 sites of disease (amenable to further local treatment), 2 progressed with widespread metastatic disease, and one patient had local progression only.Conclusions: HIGRT to adrenal metastases was tolerated with low toxicity in OM patients. Treated metastasis control rates were promising. Progression in new metastatic sites was common in this heavily pretreated population, although the majority of patients progressed with limited sites of disease. Further investigation should focus on integrating HIGRT with systemic therapy.
Rudra, S,
Hypofractionated Image-guided Radiation Therapy for Adrenal Metastases. Radiological Society of North America 2011 Scientific Assembly and Annual Meeting, November 26 - December 2, 2011 ,Chicago IL.
http://archive.rsna.org/2011/11031601.html
