Re-irradiation with intensity-modulated radiation therapy for pelvic recurrent cervical cancer
Hye Jin Kang,
Korea Republic of
PO-1430
Abstract
Re-irradiation with intensity-modulated radiation therapy for pelvic recurrent cervical cancer
Authors: Hye Jin Kang1, Myungsoo Kimm1
1Incheon St. Mary's Hospital, Radiation Oncology, Incheon, Korea Republic of
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Purpose or Objective
Radiation therapy (RT) is generally used as a primary treatment for cervical cancer because it responds well to radiation. The main recurrence pattern in cervical cancer is intra-pelvic recurrence. This study aimed to investigate the feasibility and safety of re-irradiation using intensity-modulated radiation therapy (IMRT) for patients with cervical cancer who experienced intra-pelvic recurrence.
Material and Methods
We retrospectively analyzed 22 patients with recurrent cervical cancer treated with re-irradiation for intra-pelvic recurrence using IMRT between July 2006 and July 2020. The irradiation dose and volume were determined according to the range considered safe considering the tumor , location, and previous irradiation dose. The median re-irradiation dose to the recurrent site was 50 (range: 26–56) Gy. The median cumulative dose from the previous RT and re-irradiation course was 110 (range: 83–148) Gy.
Results
The median follow-up period was 15 (range: 3–120) months, and the overall response rate was 63.6%. Of the symptomatic patients, 90% experienced symptom relief after treatment. The 1- and 2-year local progression free survival (LPFS) rates were 36.8% and 30.7%, respectively, whereas the 1- and 2-year overall survival (OS) rates were 68.2% and 25.0%, respectively. Multivariate analysis revealed that the interval between irradiations and gross tumor volume (GTV) were significant prognostic factors for LPFS. The response to re-irradiation showed borderline statistical significance for LPFS. The GTV and response to re-irradiation were also independent prognostic factors for OS. Grade 3 late toxicities were observed in 4 (18.2%) of the 22 patients. Recto- or vesico-vaginal fistula occurred in 4 patients. The irradiation dose was associated with fistula formation with borderline significance.
Conclusion
Re-irradiation using IMRT is a safe and effective treatment strategy for patients with recurrent cervical cancer who previously received RT. The interval between irradiations, tumor , response to re-irradiation, and radiation dose were the main factors affecting efficacy and safety.