Descriptive analysis of prostate cancer pathology data from diagnosis and surgery in men from the 45 and Up Study

Information available from the New South Wales Cancer Registry (NSWCR) about the aggressiveness of prostate cancer is limited to the summary stage variable 'degree of spread', which contains a high proportion of cases defined as 'unknown'. In this study we demonstrate the feasibility of obtaining and analysing prostate cancer pathology data from stored pathology records. Pathology data were extracted from stored pathology records of incident prostate cancer cases in men participating in the 45 and Up Study, a large Australian prospective cohort study, who were diagnosed between January 2006 and December 2013. Baseline questionnaires from the 45 and Up Study were linked to the NSWCR. Demographic and pathology items were tabulated and associations described. We evaluated the completeness of pathological characteristics by degree of spread of cancer at diagnosis. Among the 123,921 men enrolled in the 45 and Up Study, 5,091 had incident prostate cancer and 5,085 were linked to a pathology record. The most complete variables included grade group of diagnostic (85.8%) and surgical (99.8%) specimens, margin status (98.1%), extraprostatic extension (95.1%) and seminal vesicle invasion (96.8%). Most diagnostic specimens were grade group 1 (26.6%) or 2 (23.5%). Of the 5,085 cases, 30.8% were classified by the NSWCR with unknown degree of spread; a pathology record could be extracted for 99.4% of these. The unknown degree of spread cases had similar levels of completeness and distribution of diagnostic and surgical pathology features to those with a localised degree of spread. This study demonstrated the feasibility of obtaining and analysing data derived from pathology reports from centralised state-based cancer registry notifications. Supplementing degree of spread information with pathology data from diagnosis and surgery will improve both the quality of research and policy aimed at improving the lives of men with prostate cancer.