Associations among ancestry, geography and breast cancer incidence, mortality, and survival in Trinidad and Tobago

Abstract

Breast cancer (BC) is the most common newly diagnosed cancer among women in Trinidad and Tobago (TT) and BC mortality rates are among the highest in the world. Globally, racial/ethnic trends in BC incidence, mortality and survival have been reported. However, such investigations have not been conducted in TT, which has been noted for its rich diversity. In this study, we investigated associations among ancestry, geography and BC incidence, mortality and survival in TT. Data on 3767 incident BC cases, reported to the National Cancer Registry of TT, from 1995 to 2007, were analyzed in this study. Women of African ancestry had significantly higher BC incidence and mortality rates (Incidence: 66.96; Mortality: 30.82 per 100,000) compared to women of East Indian (Incidence: 41.04, Mortality: 14.19 per 100,000) or mixed ancestry (Incidence: 36.72, Mortality: 13.80 per 100,000). Geographically, women residing in the North West Regional Health Authority (RHA) catchment area followed by the North Central RHA exhibited the highest incidence and mortality rates. Notable ancestral differences in survival were also observed. Women of East Indian and mixed ancestry experienced significantly longer survival than those of African ancestry. Differences in survival by geography were not observed. In TT, ancestry and geographical residence seem to be strong predictors of BC incidence and mortality rates. Additionally, disparities in survival by ancestry were found. These data should be considered in the design and implementation of strategies to reduce BC incidence and mortality rates in TT.

The Rise in Mortality from Breast Cancer in Young Women: Trend Analysis in Brazil

“…There is a need for a national dialogue on regional disparities and the implementation of equal access and use of a quality treatment for cancer, with early detection, genetic and genomics research, molecular subtyping of breast cancer, sensitizing specific actions and appropriate therapy [29]. It must be considered that developing countries such as Brazil are subjected to serious problems in access to health services, diagnosis and modern treatments [30], which contributes to the increased mortality rates from breast cancer between regions and States.…”

Gynecologic cancer mortality in Trinidad and Tobago and comparisons of mortality-to-incidence rate ratios across global regions

“…Previously described imputation methodologies were used to ascribe ethnic ancestry to the gynecologic cancer cases with unreported ancestry [12]. Multi-variable-adjusted logistic regression models (adjusting for age at diagnosis, ethnic ancestry, geographic residence, tumor stage, and receipt of any treatment) were used to estimate mortality risks by gynecologic cancer site.…”

“…The methods used to calculate the age-standardized incidence and mortality rates, that were included in the calculations of the MIRs, were previously described [12]. Briefly, age-standardized incidence and mortality rates (per 100,000) were standardized to the Segi World Standard 1960 population [16] to allow for comparisons with IARC datasets.…”

“…While there are some preliminary reports that screening can improve survival rates, the impact of screening on mortality from ovarian and endometrial cancers is still an area of active research [31]. Additionally, well-established germline mutations in breast cancer susceptibility genes such as BRCA1 and BRCA2, which have founder effects leading to increased risk for breast cancer incidence and mortality [32–38], are likely associated with the high rates of breast cancer incidence and mortality rates [12] and high rates of ovarian cancer mortality in TT.…”

“…The economy, population demographics, and healthcare system, including an established cancer registry, present a unique opportunity to analyze gynecologic cancer rates in TT, which is classified as a high-income yet developing country with universal access to healthcare [12]. In this study, we describe the factors associated with gynecologic cancer mortality risks in TT and compare mortality-to-incidence rate ratios (MIRs) for gynecologic cancers diagnosed in TT to those across regions and select countries around the world, using the most up-to-date data available from the National Cancer Registry of TT, and data from the GLOBOCAN 2012 Incidence and WHO Mortality Database 2012 data files.…”