Overall and disease-free survival in women being over-weight/obese at the diagnosis of breast cancer

A single-center observational study.

Abstract

Introduction: This study aimed to evaluate the clinical, pathological, and histological tumor characteristics and their association with recurrence, metastasis, and prognosis in terms of overall and disease-free survival of patients who are overweight or obese at the time of breast cancer diagnosis.

Materials and methods: We conducted a descriptive, single cohort, retrospective study in an oncologic center of reference in Medellín - Colombia. Women older than 18 years, with early or advanced invasive breast cancer between 2012-2017, who presented with a BMI > 25 kg/m2 when diagnosed were included. The survival median was calculated using the Kaplan-Meier method, and the differences between them were determined using the Log Rank Test.

Results: 1.349 patients were included. The overall mortality was 13.6% and increased proportionally with BMI. We identified 12.6% of recurrences. However, the association with BMI was not statistically significant. Poor tumor differentiation, lymphovascular invasion, and advanced tumor stages were associated with higher mortality in univariate analysis.

Conclusion:  A positive and independent association between elevated BMI, mortality, and risk of recurrence in breast cancer patients was demonstrated. There is also a relation between aggressive tumor phenotypes and worst prognosis tumoral features. We suggest modifying lifestyle and a multidisciplinary approach as strategies that could impact the outcomes.