Socioeconomic Deprivation and Invasive Breast Cancer Incidence by Stage at Diagnosis: A Possible Explanation to the Breast Cancer Social Paradox
by
, , , and
Giulio Borghi
1,*,
Claire Delacôte
1,2,
Solenne Delacour-Billon
1,2,3,
Stéphanie Ayrault-Piault
1,2,3,
Tienhan Sandrine Dabakuyo-Yonli
3,4,
Patricia Delafosse
3,5,
Anne-Sophie Woronoff
3,6,
Brigitte Trétarre
3,7,8,
Florence Molinié
1,2,3,8 and
Anne Cowppli-Bony
1,2,3,8 1
Loire-Atlantique/Vendée Cancer Registry, 44093 Nantes, France
2
SIRIC ILIAD INCa-DGOS-INSERM-ITMO Cancer_18011, CHU Nantes, 44000 Nantes, France
3
French Network of Cancer Registries (FRANCIM), 31000 Toulouse, France
4
Côte d’Or Breast and Gynaecologic Cancer Registry, INSERM U1231, 21000 Dijon, France
5
Isère Cancer Registry, 38000 Grenoble, France
6
Doubs Cancer Registry, 25000 Besançon, France
7
Hérault Cancer Registry, 34000 Montpellier, France
8
EQUITY Research Team (Certified by the French League Against Cancer), CERPOP, UMR 1295, Université Toulouse III Paul Sabatier, 31000 Toulouse, France
*
Author to whom correspondence should be addressed.
Cancers 2024, 16(9), 1701; https://doi.org/10.3390/cancers16091701
Submission received: 8 March 2024
/
Revised: 16 April 2024
/
Accepted: 22 April 2024
/
Published: 27 April 2024
(This article belongs to the Special Issue Disparities in Cancer Prevention, Screening, Diagnosis and Management)
Simple Summary
Compared to socioeconomically affluent areas, lower breast cancer incidence and similar or higher mortality have been reported in deprived areas. We provide a possible explanation to this paradox, by estimating and comparing incidence by stage at diagnosis between different levels of area-based socioeconomic deprivation in France. As deprivation increased, all-stages and early (stage I and stage II) invasive breast cancer incidence significantly decreased, while advanced (stage III–IV) breast cancer incidence significantly increased.
Abstract
In this study, we assessed the influence of area-based socioeconomic deprivation on the incidence of invasive breast cancer (BC) in France, according to stage at diagnosis. All women from six mainland French departments, aged 15+ years, and diagnosed with a primary invasive breast carcinoma between 2008 and 2015 were included (n = 33,298). Area-based socioeconomic deprivation was determined using the French version of the European Deprivation Index. Age-standardized incidence rates (ASIR) by socioeconomic deprivation and stage at diagnosis were compared estimating incidence rate ratios (IRRs) adjusted for age at diagnosis and rurality of residence. Compared to the most affluent areas, significantly lower IRRs were found in the most deprived areas for all-stages (0.85, 95% CI 0.81–0.89), stage I (0.77, 95% CI 0.72–0.82), and stage II (0.84, 95% CI 0.78–0.90). On the contrary, for stages III–IV, significantly higher IRRs (1.18, 95% CI 1.08–1.29) were found in the most deprived areas. These findings provide a possible explanation to similar or higher mortality rates, despite overall lower incidence rates, observed in women living in more deprived areas when compared to their affluent counterparts. Socioeconomic inequalities in access to healthcare services, including screening, could be plausible explanations for this phenomenon, underlying the need for further research.
