Salvage stereotactic body radiotherapy in oligometastatic gynaecological cancer
PD-0813
Abstract
Salvage stereotactic body radiotherapy in oligometastatic gynaecological cancer
Authors: Martina Midulla1,2, Andrei Fodor1, Flavia Zerbetto1, Chiara Lucrezia Deantoni1, Roberta Tummineri1, Laura Giannini1,2, Sara Broggi3, Miriam Torrisi1,2, Federica Ferrario1,2, Chiara Chissotti1,2, Stefano Lorenzo Villa1,2, Paola Mangili3, Claudio Fiorino3, Stefano Arcangeli4,2, Nadia Gisella Di Muzio1,5
1IRCCS San Raffaele Scientific Institute, Department of Radiation Oncology, Milano, Italy; 2University of Milano-Bicocca, Department of Radiation Oncology, Milano, Italy; 3IRCCS San Raffaele Scientific Institute, Medical Physics, Milano, Italy; 4ASST- San Gerardo Hospital, Department of Radiation Oncology, Monza, Italy; 5Vita-Salute San Raffaele University, Department of Radiation Oncology, Milano, Italy
Show Affiliations
Hide Affiliations
Purpose or Objective
Patients (pts) with oligometastatic disease may benefit from treatment of all metastatic sites with stereotactic body radiation therapy (SBRT). In this retrospective study we analyzed the clinical outcomes of stereotactic treatment on different metastatic sites in pts with gynecological cancers.
Material and Methods
From 4/09 to 10/22, 123 lesions in 68 pts were treated with SBRT. In 27 pts (39.7%) multiple SBRT were prescribed on synchronous and metachronous lesions. Eleven lesions were treated with Image Guided-helical Intensity Modulated Radiotherapy (IG-IMRT) to a median dose of 40(35-63) Gy in 5 (5-10) median fractions prescribed at 95% of the Planning Target Volume (PTV). One hundred twelve lesions were treated with robotic SBRT to a median dose of 40 (18-60) Gy in a median of 5 (1-8) fractions, prescribed at a median isodose of 80% (67-84%). Thirteen PTVs (10.5%) were in the same field of previous adjuvant or salvage radiotherapy performed with IG-IMRT with a median dose of 50.4Gy. Primary histology was: uterine in 41.5%, ovarian in 32.5%, cervical in 16.3%, vaginal in 5.7% and other (fallopian tubes and vulva) in 2.4% of lesions, respectively. Target locations were lymph nodes 50.4%, lung 32.5%, bone and soft tissue 4.9%, central nervous system 6.5%, and liver 5.7%. GTV was defined by the fusion of CT, PET/CT and/or MRI images. Toxicity was assessed using CTCAE version 4.03 criteria.
Results
Median age at the treatment was 62 years (3-88). Median follow-up was 18.2 months (0–75.4). Seventeen pts (13.8%) presented grade (G) 1-2 acute toxicity. No grade ≥3 acute toxicity was observed. Three pts presented late toxicity: one had G2 rib pain persistent up to 28 months after treatment, one had G1 hand paraesthesia, and the last one, irradiated on D12 (lytic lesion), a spine fracture 12 months later, with G3 bilateral leg pain and motor deficit. After treatment 56.9% of targets had a complete response, 25.2% a partial response, 6.5% a progressive disease, while 4.9 % of patients died and were lost to follow up. Local relapse free survival (LRFS) on a per lesion analysis, at 12 and 24 months, was 90.1 % and 86.2%, respectively, with a median LRFS not reached (See Fig.1). Distant metastasis free survival (DMFS), overall survival (OS) and cancer specific survival (CCS) were analysed on a per patient, and not per lesion basis. DMFS was 49% at 12 months, 26.9% at 24 months and 23.9% at 36 months, with a median of 10.5 months (See Fig2a). OS at 12, 24 and 36 months was 71%, 59.7% and 51.8%, respectively, with a median of 59.4 months (See Fig2b). Median CSS value at 12, 24 and 36 months was 74.3%, 62.8% and 57.1%, respectively (See Fig2c).
Conclusion
SBRT used in the management of the oligometastatic gynaecological cancer led to good results in terms of local control with acceptable toxicity. Distant progression remains the primary site of failure in this setting.