A population-based study of cervix cancer: incidence, management and outcome in the Canadian province of Saskatchewan

Aims

To document the incidence, management and outcome of uterine cervix cancer in the Canadian province of Saskatchewan. To compare provincial results of low dose rate (LDR) and high dose rate (HDR) brachytherapy in this population.

Materials and methods

We carried out a retrospective population-based cohort study of all uterine cervix cancer cases in Saskatchewan diagnosed between 1985 and 2001. We used data from the provincial cancer registry for incident cases, the provincial death registry for vital status information and chart reviews for treatment and toxicity information.

Results

In total, 714 cases of uterine cervix cancer were identified. Stage distribution was IA 22.7%, IB 31.8%, II 19.1%, III 18.4%, IV 6.8%; 81.2% were squamous cell carcinoma, 13.4% adenocarcinoma, 1.5% adenosquamous, 0.9% small cell and 3.1% other. The annual crude incidence rate of uterine cervix cancer in Saskatchewan ranged from 6.5 to 12.3% between 1985 and 2001. The 5-year cause-specific survival rate ranged from 100% for stage IA1 to 22% for stage IV. One hundred and seven patients were treated with LDR and 37 with HDR with similar stage distribution. The 5-year cause-specific survival rate was 56% for HDR and 67% for LDR (P = 0.72). For 43 patients managed with external beam radiotherapy alone, outcome was poor for stage IIB to IIIB. The most common acute toxicities of radiation treatment were diarrhoea (60%) and abdominal cramps (12.5%). The common chronic toxicities were vaginal stenosis (5.5%) and small bowel obstruction (4%).

Conclusions

Our population-level outcomes are in keeping with published observed results and provide some of the first Canadian population-level data on HDR and LDR outcomes. We found no significant different in cause-specific survival between patients managed with HDR and LDR, although interpretation is limited by patient numbers. Our results for external beam radiotherapy alone emphasise the vital role brachytherapy plays in the management of cervical cancer.