Breast Cancer in Jamaica: Stage, Grade and Molecular Subtype Distributions Across Age Blocks, the Implications for...

Breast cancer is the most commonly diagnosed and leading cause of cancer-related morbidity and mortality in females worldwide. Significant disparities exist in breast cancer incidence and mortalities between low- to middle- and high-income countries. The purpose of this study was to analyze the distribution of prognostic and predictive clinicopathological features of invasive breast cancer at a single institution in Jamaica across three age groups.

Data from patients diagnosed with invasive breast cancer who underwent definitive surgery between August 2017 and September 2018 were identified. The patients were divided into three age groups (< 50, 50 - 59 and > 59 years) and the distribution of tumor size, grade, molecular subtype, nodal status and anatomic stage were determined and compared with the US population registry. Comparisons of the various characteristics were performed using the Fisher's exact test.

Ninety-nine definitive operations were performed and met the criteria for analysis. Average age at the time of diagnosis was 54 years compared to 62 years reported in the US databases. Thirty-six percent of the patients presented below age 50 years, which was twice the corresponding rate reported for Caucasian females (18%) in the USA. Fifty percent of patients in our registry had axillary lymph node metastases at presentation and they were younger than patients with negative axillary nodes (95% confidence interval (CI) -12.06 to -1.93, P = 0.007). Patients in the age group less than age 50 years were more likely to have advanced stage, high histological grade cancers compared to the older age blocks (95% CI 0.039 - 0.902, P = 0.033).

Invasive breast cancer presents at an earlier age in Jamaican women and is associated with poor prognostic features such as high rates of axillary lymph node metastases, high histological grade, advanced stage, triple-negative subtypes and low luminal A subtypes.