Presentation Intervals and the Impact of Delay on Breast Cancer Progression in a Black African Population

Abstract

BACKGROUND: The help-seeking interval and primary-care interval are points of delays in breast cancer presentation. To inform future intervention targeting early diagnosis of breast cancer, we described the contribution of each interval to the delay and the impact of delay on tumor progression. METHOD: We conducted a multicentered survey from June 2017 to May 2018 hypothesizing that most patients visited the first healthcare provider within 60 days of tumor detection. Inferential statistics were by t-test, chi-square test, and Wilcoxon-Signed Rank test at p-value 0.05 or 95% confidence limits. Time-to-event was by survival method. Multivariate analysis was by logistic regression. RESULTS: Respondents were females between 24 and 95 years (n=420). Most respondents visited FHP within 60 days of detecting symptoms (230 (60%, 95% CI 53-63). Most had long primary-care (237 of 377 (64% 95% CI 59-68) and detection-to-specialist (293 (73% (95% CI 68-77)) intervals. The primary care interval (median 106 days, IQR 13-337) was longer than the help-seeking interval (median 42 days, IQR 7-150) Wilcoxon signed-rank test p= 0.001. There was a strong correlation between the length of primary care interval and the detection-to-specialist interval (r= 0.9, 95% CI 0.88- 0.92). Patronizing the hospital, receiving the correct advice, and having a big tumor (>5cm) were associated with short intervals. Tumors were detected early, but most became advanced before arriving at the specialist clinic. The difference in tumor size between detection and arriving at a specialist clinic was 5.0±4.9cm (95% CI 4.0-5.0). The hazard of progressing from early to locally advanced disease was least in the first 30 days (3%). The hazard was 31% in 90 days. CONCLUSION: Most respondents presented early to the first healthcare provider, but most arrived late at a specialist clinic. The primary care interval was longer than the help-seeking interval. Most tumors were early at detection but locally advanced before arriving in a specialist clinic. Interventions aiming to shorten the primary care interval will have the most impact on time to breast cancer presentation for specialist oncology care in Nigeria.