Ovarian cancer in Manitoba: trends in incidence and survival, 1992–2011

  • P. Lambert CancerCare Manitoba
  • K. Galloway CancerCare Manitoba
  • A. Altman University of Manitoba; CancerCare Manitoba;
  • M.W. Nachtigal University of Manitoba; CancerCare Manitoba
  • D. Turner CancerCare Manitoba; University of Manitoba
Keywords: Ovarian cancer, survival, population-based registries

Abstract

Background

Because the International Cancer Benchmarking Partnership, in a study of diagnosis years between 1995 and 2007, showed lower-than-expected survival for Manitoba’s ovarian cancer patients, we undertook an analysis to describe the features of ovarian cancer diagnosed in Manitoba during a 20-year period. We also determined the most recent trends in survival to see if the previous results were sustained.

Methods

In this retrospective cohort study, ovarian cancer cases diagnosed during 1992–2011 were extracted from the Manitoba Cancer Registry. The incidence of ovarian cancer was calculated for the overall group and for age, morphology, residence, treatment, and stage. Trends over time, with a particular focus on changes that might correlate with poor survival, were analyzed. The 1- and 3-year relative survival rates were also calculated.

Results

The incidence of ovarian cancer did not vary over time (p = 0.640), even when stratified by age or morphology groups. Use of adjuvant chemotherapy decreased (p = 0.005) and use of neoadjuvant chemotherapy increased over time (p = 0.002). Diagnoses of stage iv cancers declined over time (p < 0.020). Trends in incidence did not coincide with previously observed decreases in relative survival.

Conclusions

A decline in diagnoses of stage iv ovarian cancer could be responsible for a recent increase in relative survival. However, sample size might have limited power in some analyses, and the previously reported decrease in relative survival might have been due to a random fluctuation in the data. Future efforts will focus on continued monitoring of the patterns of ovarian cancer presentation and outcomes in Manitoba.


Author Biographies

P. Lambert, CancerCare Manitoba
Epidemiology and Cancer Registry
K. Galloway, CancerCare Manitoba
Epidemiology and Cancer Registry
A. Altman, University of Manitoba; CancerCare Manitoba;
Department of Obstetrics Gynecology and Reproductive Sciences; Division of Gynecologic Oncology,
M.W. Nachtigal, University of Manitoba; CancerCare Manitoba
Department of Obstetrics Gynecology and Reproductive Sciences; Department of Biochemistry and Medical Genetics; Research Institute in Oncology and Hematology
D. Turner, CancerCare Manitoba; University of Manitoba
Epidemiology and Cancer Registry; Department of Community Health Sciences
Published
2017-04-27
How to Cite
Lambert, P., Galloway, K., Altman, A., Nachtigal, M., & Turner, D. (2017). Ovarian cancer in Manitoba: trends in incidence and survival, 1992–2011. Current Oncology, 24(2), e78-e84. https://doi.org/10.3747/co.24.3312
Section
Cancer Control and Prevention