Disease profile in England: Incidence, mortality, stage and survival for ovary, fallopian tube and primary peritoneal carcinomas (January 2020)

To describe the incidence, stage, mortality and survival profile of ovarian, fallopian tube and female primary peritoneal cancers (hereafter ‘ovarian cancer’) including geographical variation thereof.

Incidence rates are described for cases diagnosed in England between 2015-2017, with stratification by stage at diagnosis. Survival is reported for cases diagnosed during the same period, with one- and five-year net survival rates reported for cases diagnosed 2013-2017. Incidence and survival are also reported for the 2001-2017 diagnoses, allowing for an exploration of longer-term trends. Mortality is reported for deaths occurring during 2015-17.

Directly age-standardised rates are included for incidence and mortality figures to allow the comparison of rates across Cancer Alliances, Sustainability and Transformation Partnerships (STPs) and CCGs.

Analyses utilised routine data available in the National Cancer Registration Dataset (NCRD), which captures information on all cancer diagnoses in England, including pathology details, patient and tumour characteristics, death certificates and important clinical parameters such as disease stage.

Completeness of stage data varied substantially by geography. Improved capture of staging determined by multidisciplinary teams would lead to better data quality for reporting. Mortality reporting is also limited by a lack of granularity of coding on death certificates, which is restricted to ICD-10 codes only. This contrasts with cancer registrations, which incorporate morphological coding.

The main findings of the report were:

1. The incidence rate of ovary, fallopian tube and primary peritoneal carcinomas in England remained reasonably stable between 2001 and 2017.
2. Incidence and mortality varied among CCGs and Cancer Alliances, with rates in some areas varying from the population average by magnitudes greater than might be expected by chance (2 standard deviations (SD) or more from the average).  Data is presented, as shown in Figure 1 below. Here, statistical outliers are shown above and below the dotted lines representing positions greater than two standard deviations (SD) from the population average. Larger population geographies are situated towards the right-hand side of the plots, where the lines of the funnel plot converge as population size and statistical certainly increase. Statistically significant outliers suggest that there may be genuine differences between areas that merit further investigation at a local level.

Figure 1 Ovary, fallopian tube and primary peritoneal carcinomas: directly age standardised incidence rates by CCG, 2015 to 2017

3. The proportions of patients diagnosed at early and late stages varied considerably around the country; some of this variability is likely due to data completeness but other factors should also be considered (Figure 2 below).

Figure 2 Stage at diagnosis of ovary, fallopian tube and primary peritoneal carcinomas by CCG, 2015 to 2017.

4. Survival of patients has been improving since 2001, with one-year net survival having increased from 57.5% for diagnoses in 2001-2005 to 68.0% for patients diagnosed in the period 2013-2017. In contrast to some previously reported survival figures, these exclude borderline tumours which generally have an excellent prognosis and include primary peritoneal malignancy which is commonly associated with poor outcomes. This improvement in one-year survival may reflect progress in diagnosing the disease sooner, with increased awareness of the symptoms amongst women and primary care practitioners and improved diagnostic pathways, enabling more women to be diagnosed while still healthy enough to undergo treatment. Five-year survival was also observed to have increased, which may reflect improvements in surgical and chemotherapy treatments.
5. Survival varied significantly between the 19 Cancer Alliances. One-year net survival ranged between 62.9% and 75.2%, and five-year net survival varied between 28.6% and 49.6%.

Figure 3 Net survival rates of patients with ovary, fallopian tube and primary peritoneal carcinomas excluding borderlines at one and 5 years by Cancer Alliance, 2013 to 2017 diagnoses.