Stereotactic body radiotherapy in oligometastatic cervical cancer (MITO-RT2/RAD study): a collaboration of MITO, AIRO GYN, and MaNGO groups

Abstract

ObjectiveThis retrospective, multicenter study analyzes the efficacy and safety of stereotactic body radiotherapy in a large cohort of patients with oligometastatic/persistent/recurrent cervical cancer.MethodsA standardized data collection from several radiotherapy centers that treated patients by stereotactic body radiotherapy between March 2006 and February 2021 was set up. Clinical and stereotactic body radiotherapy parameters were collected. Objective response rate was defined as a composite of complete and partial response, while clinical benefit included objective response rate plus stable disease. Radiation Therapy Oncology Group/European Organization for Research and Treatment of Cancer and Common Terminology Criteria for Adverse Events scales were used to grade toxicities. The primary endpoints were the rate of complete response to stereotactic body radiotherapy, and the 2 year actuarial local control rate on a ‘per lesion’ basis. The secondary end points were progression-free survival and overall survival, as well as toxicity.ResultsA total of 83 patients with oligometastatic/persistent/recurrent cervical cancer bearing 125 lesions treated by stereotactic body radiotherapy at 15 different centers were selected for analysis. Of the sites of metastatic disease, lymph node metastases were most common (55.2%), followed by parenchyma lesions (44.8%). Median total dose was 35 Gy (range 10–60), in five fractions (range 1–10), with a median dose/fraction of 7 Gy (range 4–26). Complete, partial, and stable response were found in 73 (58.4%), 29 (23.2%), and 16 (12.8%) lesions, respectively, reaching 94.4% of the clinical benefit rate. Forty-six (55.4%) patients had a complete response. Patients achieving complete response on a ‘per lesion’ basis experienced a 2 year actuarial local control rate of 89.0% versus 22.1% in lesions not achieving complete response (p<0.001). The 2 year actuarial progression-free survival rate was 42.5% in patients with complete response versus 7.8% in patients with partial response or stable or progressive disease (p=0.001). The 2 year actuarial overall survival rate was 68.9% in patients with complete response versus 44.3% in patients with partial response or stable or progressive disease (p=0.015). Fifteen patients (18.1%) had mild acute toxicity, totaling 29 side events. Late toxicity was documented in four patients (4.8%) totaling seven adverse events.ConclusionOur analysis confirmed the efficacy of stereotactic body radiotherapy in oligometastatic/persistent/recurrent cervical cancer patients. The low toxicity profile encourages the wider use of stereotactic body radiotherapy in this setting.

Intensity-Modulated Radiation Therapy for Uterine Cervical Cancer to Reduce Toxicity and Enhance Efficacy – an Option or a Must?: A Narrative Review

“…According to a more recent study, definitive RT to oligometastatic sites shows a 3-year OS rate of 65% [ 79 ]. SABR to oligometastatic cervical cancer achieves complete response in 55.4% with 2-year LC rate of 89% [ 80 ]. The 2-year OS approximated 70% in patients with complete response versus 44% in patients with suboptimal response.…”

Stereotactic Body Radiation Therapy in Gynecologic Oligometastases: An Effective but Underutilized Approach

“…Complete response after SBRT was correlated with improved overall and progressionfree survival. SBRT has been evaluated in primary oligometastatic cervical cancer in the recently published MITO RT2/RAD study [19] which represents the largest retrospective cohort of patients with oligometastases from primary cervical cancer treated with SBRT. A total of 83 patients with 125 oligometastatic cervical cancer lesions were treated with SBRT.…”

Improving cervical cancer survival–A multifaceted strategy to sustain progress for this global problem

“…48,49 Early retrospective data suggest similar efficacy and a low toxicity profile in patients who have oligometastatic cervical cancer. 50 Systemic therapy with singlet cytotoxic chemotherapies are largely ineffective, showing only about a 10% response rate with significant toxicities. Targeted therapies combined with platinum doublet chemotherapy have shown the most promise to date.…”

“…Improved survival was demonstrated with stereotactic body RT to oligometastases in patients with other cancers 48,49 . Early retrospective data suggest similar efficacy and a low toxicity profile in patients who have oligometastatic cervical cancer 50 . Systemic therapy with singlet cytotoxic chemotherapies are largely ineffective, showing only about a 10% response rate with significant toxicities.…”