Study On Interstitial Brachytherapy Of Locally Advanced Cervical Cancer

Objective: American brachytherapy Society(ABS) recommended interstitial brachytherapy(ISBT) for locally advanced cervical cancer(LACC) when target was hardly covered by intracavitary brachytherapy(ICBT) or vaginal stenosis. ISBT can reach tumor directly and regression well. The organs at risk got small radiation dose. The aim of this study is to analysis the status of ISBT on cervical cancer all over the word and to compare the differences and find problems. Clinical efficacy and safety of high dose rate on interstitial brachytherapy(HDR-IS BT) were investigated for LACC and then to provide reference for clinical diagnosis and treatment.METHODS: Some electronic databases were retrieved and some related studies were collected about ISBT of cervical cancer. The reporting quality and interstitial mode on English and Chinese studies were compared by bibliometric analysis. Meta-analysis was carried out about HDR-ISBT feature and outcomes related to survival using binary one arm of Meta Analyst Beta3.13 software. Outcomes were computed and then draw forest plots. After collecting clinical retrospective cases about 21 ISBT and 21 N-ISBT, outcomes of short-term efficacy, safety and survival were analyses.Results:①A total of 85 studies were included, 35 in English and 50 in Chinese. 24.7%(21/85) were clinical controlled studies. The reporting rate was low in follow-up time, interstitial feature and treatment mode. 88.2%(60/68) was using HDR-ISBT. The mode of 5.5-6Gy per frequency(f), 5-6f twice a day was used in 32%(8/25) in English studies by trans-perineum template. Unarmed ISBT on 6-12Gy/f, 1-3f weekly was used in 53.1%(17/32) Chinese studies.②8 studies were included with 429 patients. 50.0%(4/8) were using ISBT after one week of EBRT. The mode of 5-7Gy/f and 4-6f in 75.0%(6/8). The result by meta-analysis showed that LC of three or five years were 90.8%[95%CI(82.7%, 95.4%)] and 73.0% respectively. OS of three or five years were 60.0%[95%CI(55.1%, 65.6%)] and 47.8%[95%CI(41.0%, 54.7%)]. DFS of three or five years were 62.2%[95%CI(48.7%, 74.1%)] and 55.2%[95%CI(43.4%, 66.3%)]. ③It was found that ISBT compared to N-ISBT had higher efficiency in retrospective study, but the infection-related complications were increased. The survival showed no significant difference.Conclusion:The reporting rate of ISBT clinical features for cervical cancer is low based on current research, especially in Chinese studies. Dose, mode and opportunity were significant difference. ISBT on LACC was safe and more effective in short time.The toxicity was small. The survival had no difference.