Incidence, mortality and receptor status of breast cancer in African Caribbean women: Data from the cancer registry of Guadeloupe.

BACKGROUND: Geographical disparities in breast cancer incidence and outcomes are reported worldwide. Women of African descent show lower incidence, higher mortality rates and earlier age of onset. We analyzed data from the cancer registry of Guadeloupe for the period 2008-2013. METHODS: We describe breast cancer characteristics by molecular subtype, as well as estimated observed and net survival. We used Cox proportional hazard models to determine associations between cancer subtypes and death rate, adjusted for variables of interest. RESULTS: Overall, 1275 cases were recorded with a mean age at diagnosis of 57(±14) years. World standardized incidence and mortality were respectively 71.9/100,000 and 14.1/100,000 person-years. Age-specific incidence rates were comparable to European and US populations below the age of 45, and higher in Guadeloupean women aged between 45 and 55 years. Overall, 65.1% of patients were hormone receptor (HR)+ and 20.1% were HR-. Triple negative breast cancers (TNBC) accounted for 14% of all cases, and were more frequent in patients under 40 (21.6% vs. 13.4%, p=0.02). Five-year net survival was 84.9% [81.4-88.6]. It was higher for HR+/Her2+ and HR+/Her2- subtypes, and lower for HR-/Her2+ and TNBC patients. CONCLUSION: We found high age-specific incidence rates of breast cancer in women aged 45 to 55 years, which warrants further investigation in our population. However, this population of mainly African descent had good overall survival rates, and data according to subtypes are consistent with those reported internationally. These results may suggest that poorer survival in other African descent populations may not be an inherent feature of the disease but may be amenable to improvement.

Prostate cancer as an environmental disease: an ecological study in the French Caribbean islands, Martinique and Guadeloupe.

Using a transdisciplinary methodological approach we have conducted a multifactorial analysis in Martinique and Guadeloupe in order to elucidate the aetiology of prostate cancer. In 2002, world age standardized rates of prostate cancer were 152 new cases per 100,000 person-years in the two islands; one of the highest worldwide rates and much higher than those reported for other Caribbean islands and metropolitan France. Using a linear regression analysis, we found that the growth curves of incidence rates for Martinique and metropolitan France have been significantly diverging since 1983. That these curves are not parallel suggests that although a Caribbean genetic susceptibility factor may be involved in carcinogenesis, this factor cannot per se account for the observed growing incidence. On the basis of mapping analysis of soil pollution, we further showed that water contamination by pesticides originates from banana plantations. Moreover, we have established retrospectively that general population subjects investigated in 1972 in Martinique for the presence of organochlorinated pesticides in their adipose tissue had been contaminated by extremely high levels of DDT, DDE, alpha, beta and gammaHCH, aldrin and dieldrin. Our study leads to the conclusion that the growing incidence of prostate cancer cannot be related either to a modification of ethnographic factors nor to a change in lifestyle and therefore suggests that environmental factors such as the intensive and prolonged exposure to carcinogenic, mutagenic and reproductive toxin pesticides may cause prostate cancer.