The evidence supporting this protocol is provided by a meta analysisr and a phase III multicentre international randomised trial.r The 2014 Cochrane reviewr of 4 studies involving 1265 patients comparing High Dose Rate (HDR) brachytherapy with Low dose rate (LDR) intracavity brachytherapy (ICBT) in patients with locally advanced uterine cervix cancer (stage I-III).
A recent update from Liu et alr for HDR and LDR ICBT brachytherapy patients, the 5 and 10 year pooled results for overall survival RR were 0.93 (95% CI 0.84 to 1.04) and 0.79 (95% CI 0.52 to 1.20) respectively. The disease specific survival rates were 0.95 (95% CI 0.84 to 1.07) and 1.02 (95% CI 0.88 to 1.19) for 5 and 10 years respectively. At 5 years, local control RR was 0.95 (95% CI 0.87 to 1.05) and RR 1.09 (95% CI 0.83 to 1.43) for locoregional recurrence.
Both treatments were found to be equally efficacious in terms of overall survival (OS), disease specific survival (DSS), recurrence free survival (RFS) , local control rates, recurrence, metastasis except for an increase in small bowel complications for HDR RR 3.37 (95% CI 1.06-10.72) p=0.04.
Due to the potential advantages of HDR ICBT in the form of rigid immobilization, outpatient treatment, patient convenience, accuracy of source and applicator positioning and individualised treatment HDRICBT is recommended for all clinical stages of cervix cancer.rrr
EBRT + brachytherapy versus EBRT alone
Intracavitary brachytherapy is an integral component in the radical radiotherapy treatment of cervical cancer. There is a higher incidence of local failure if EBRT alone is used. Lanciano et alr analysed the pre-treatment and treatment factors which improved outcomes in the 1973 and 1978 patterns of care studies and found that the only treatment factor that had an impact on pelvic control rates was the use of intracavitary radiation.
© Int J Radiat Biol Physics 1991 Lanciano.r
Han et alr reviewed the SEER database containing 7359 patients treated for stage IB2-IVA cervical cancer between 1988 and 2009. Comparing those who received brachytherapy + EBRT vs RT alone, four year cancer specific survival was 64.3% vs 51.5% (p<0.001) and overall survival rates were 58.2% vs 46.2% (P<0.001) respectively. Despite the higher CSS and OS, a decline in the use of brachytherapy was seen from 83% in 1988 to 58% in 2009 P<0.001.
Survival by brachytherapy use for matched cohort between 2000 and 2009. (a) Cause-specific survival; (b) overall survival
© Int J Radiat Biol Physics 2013 Hanr
Alternative boost modalities
Gill et alr examined the National Cancer Data Base (NCDB) for 7654 patients with stage IIB-IVA cervical cancer treated with EBRT + Brachytherapy or IMRT/SBRT boost from 2004-2011 and found a decrease in the use of brachytherapy (96.7% to 86.1%) and a similar increase in SBRT and IMRT use (3.35 to 13.9%; p<0.01). It was found that IMRT or SBRT boost resulted in inferior overall survival (HR 1.86; 95 CI 1.35-2.55, p<0.01) when compared to brachytherapy.