title: Clinical Outcomes for Stereotactic Ablative Radiotherapy in Oligometastatic and Oligoprogressive Gynecological Malignancies.
abstract: We report single-institution clinical outcomes of women treated with stereotactic ablative radiotherapy (SABR) for oligometastatic or progressive gynecological malignancies.
  
  
  
  From 2009 to 2015, 47 lesions from 28 patients were treated with SABR and retrospectively analyzed. All patients had oligometastatic (93%) or oligoprogressive (7%) disease. Primary cancer diagnoses were 15 ovarian, 8 endometrial, 2 cervical, 2 vaginal, and 1 uterine carcinosarcoma. Treatment was delivered using a median of 5 fractions to a median total dose of 40 Gy. Targets were grouped by treatment site and assessed for response using Response Evaluation Criteria in Solid Tumors v1.1. Mean biologically effective dose and pre-SABR tumor size were compared with response. Progression-free survival (PFS) was determined using Kaplan-Meier analysis, and toxicity outcomes were graded using Common Terminology Criteria for Adverse Events version 4.03.
  
  
  
  Median follow-up was 12.8 months. Target locations were 17% liver, 21% lung, 17% paraaortic node, 26% other node, and 19% pelvic soft tissue. After treatment, 34% of targets were stable (SD), 32% had a partial response (PR), 17% had a complete response (CR), and 17% had progressive disease (PD). No failures occurred in lung or nodal targets. Mean ± standard deviation pre-SABR tumor diameter was 24 ± 22 mm. There was a significant difference in mean size between lesions that had a favorable (SD, PR, and CR) versus unfavorable response (PD) (17.2 vs 57.6 mm, P = 0.0044). Lesions that responded favorably were also more likely to have received a higher biologically effective dose (79.0 vs 59.6 Gy, P = 0.027). Median PFS was 10.8 months, and 1 patient experienced grade 3 toxicity.
  
  
  
  The SABR is a safe and effective local treatment modality in patients with oligometastatic gynecological disease. Distant progression remains the primary mode of failure in this patient population. In carefully selected patients, a combination of systemic treatment and SABR may offer long-term PFS.
authors.affiliation: *School of Medicine, University of California Irvine, Irvine; and Departments of †Radiation Oncology, ‡Gynecologic Oncology, and §Medical Oncology, University of California Los Angeles, Los Angeles, CA.
authors.forename: Shane
authors.initials: S
authors.lastname: Mesko
authors.forename: Kiri
authors.initials: K
authors.lastname: Sandler
authors.forename: Joshua
authors.initials: J
authors.lastname: Cohen
authors.forename: Gottfried
authors.initials: G
authors.lastname: Konecny
authors.forename: Michael
authors.initials: M
authors.lastname: Steinberg
authors.forename: Mitchell
authors.initials: M
authors.lastname: Kamrava
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D018450:Disease Progression; D005260:Female; D005833:Genital Neoplasms, Female / Q000000981:diagnostic imaging / Q000473:pathology / Q000532:radiotherapy*; D006801:Humans; D008875:Middle Aged; D009362:Neoplasm Metastasis; D000072078:Positron Emission Tomography Computed Tomography; D016634:Radiosurgery / Q000009:adverse effects / Q000379:methods* / Q000706:statistics & numerical data; D012189:Retrospective Studies; D016896:Treatment Outcome