Stage of diagnosis of prostate, breast and colorectal cancer in farm residents compared with other rural and urban residents in New South Wales

Abstract

Objective: To determine if stage at diagnosis of prostate, breast and colorectal cancers differs between farm, rural non-farm and urban residents. Design: Data linkage of baseline survey information from a large cohort study, with state cancer registry records from 2006 to 2009. Setting: New South Wales, Australia. Participants: New South Wales residents enrolled in the 45 and Up Study cohort. Main outcome measures: Adjusted odds ratio of nonlocalised cancer stage was modelled using binary logistic regression, controlling for commonly known cancer risk factors. Results: Overall differences in the odds ratios for later stage prostate, breast and colorectal cancer diagnosis in farm men and women compared with rural nonfarm and urban counterparts were not statistically significant, although farm men had twice the odds of either group of being diagnosed at later stage colorectal cancer. The odds of later stage prostate cancer for farm and urban men were similar, but rural non-farm men were significantly less likely than urban men to be diagnosed at later stage. Higher household income was associated with later stage breast and prostate cancer; and private health insurance with extras was negatively associated with later stage prostate cancer.Conclusions: Differences in stage of cancer diagnosis, particularly between farm and rural non-farm men, remain unexplained but were not statistically significant. Farm men may be at higher risk of later stage colorectal cancer diagnosis, which if confirmed has implications for research on possible reasons, and for the delivery of appropriate cancer diagnostic services in rural areas.

Geographical Variations in Prostate Cancer Outcomes: A Systematic Review of International Evidence

“…There were no clear patterns in study findings with characteristics, such as sample size or time period. While three Australian studies (83–85) found no evidence of geographical differentials, three others reported that rural men were more likely to be diagnosed with advanced disease (24, 55, 86). Further discrepancies in findings were evident across the nine USA-based studies, with six reporting more advanced disease among rural residents (25, 77, 81, 82) and those with poorer access to urologists (41, 79), whereas three others found no significant differences in the rates of advanced disease between urban and rural men (39, 78, 80).…”

“…There were some variations in the definition of advanced prostate cancer with three studies each basing their classification on tumor size (77, 78, 85) or prostate cancer risk groups (79, 86, 100) and one on pathological Gleason score (90). All remaining studies used a standard cancer staging system (such as the SEER Summary stage or TNM) with Stage I-II cancers consistently referred to as localized disease, Stage III as regional disease and distant/metastatic (Stage IV) cancers as advanced (18, 24, 25, 39, 58, 64, 84, 88, 92, 102), although some collectively categorized both regional and distant cancers as advanced disease (21, 41, 55, 80–83, 87, 89, 91, 93–99, 101).…”

Geographic variations in stage at diagnosis and survival for colorectal cancer in Australia: A systematic review

“…Thus, the majority of participants sampled in this review would not have been exposed to population‐wide screening. The majority of these studies reported that stage at diagnosis did not differ across geographic locations (Armstrong, O’Connell, Leong, Spigelman, & Armstrong, ; Baade et al, ; Beckmann et al, ; Depczynski, Dobbins, Armstrong, & Lower, ; Jong et al, ). Based on this, suggestions that late diagnosis may explain disparities in CRC survival and outcomes are not strongly supported.…”

“…Thus, the majority of participants sampled in this review would not have been exposed to population-wide screening. The majority of these studies reported that stage at diagnosis did not differ across geographic locations (Armstrong, O'Connell, Leong, Spigelman, & Armstrong, 2004;Baade et al, 2011b;Depczynski, Dobbins, Armstrong, & Lower, 2018;Jong et al, 2004).…”