Dados do Resumo

Título

Multiple tumors of breast cancer in women: from epidemiology factors to overall survival

Introdução

In Brazil, breast cancer (BC) is considered the deadliest malignancy and the mortality rate is rising. Several factors are linked to this increase, such as the demographic transition phase in which the number of births is dropping, so protective breastfeeding is decreasing.
Multiple primary neoplasms (MPN) are malignant tumors with distinct histological origins, non-metastatic, that occur synchronously or metachronically, BC is frequently observed in MPN patients.

Objetivo

This cohort study aimed to analyze single and multitudinous factor associations among patients, registered The National Cancer Institute (INCA), diagnosed with breast cancer associated or not with other primary tumors.

Métodos

This cohort included women with single (n=13,386) and MPN (n=1,351) breast cancer registered in INCA.
Datasets: It assessed synchronous or metachronous disease status, tumor staging, and epidemiological risk factors such as age, cancer family history, alcohol and tobacco consumption. Data was retrieved from the hospital registry of cancer (RHC) concerning data from 2000 to 2022, last updated in February 2023.
Data processing: All data was exported and analyzed on R v.4.3, using R Studio, with “tidyverse”, “survival” and “survminer” for survival analysis.
MPN classification: We filtered for women and used INCA's classification of MPN, as shown by column (MAISUMTU). Bilateral breast cancer was considered as MPN.
This work was approved by HREC (Human Research Ethics Committee) report number: 76122823.1.0000.0068

Resultados

Regarding age groups, most MPN patients were between 40 and 60 years old (48%). As expected, younger patients presented lower frequency for both, single and multiple, breast cancer (p<0.001). Concerning alcohol and tobacco consumption, there was no contribution to the occurrence of MPN. Nevertheless, former drinkers and smokers showed higher hazard ratios (HR) than patients who never smoke or drink (p<0.001).
Considering the tumor clinical stage at diagnosis, MPN patients showed lower stages, with higher stage 1 and 2 frequencies (p<0.001). Also, special histological types are more frequent in MPN patients (25%) than single BC patients (17%, p<0.001).
Numerous risk factors were considered and compared in a multivariate analysis including overall survival (years) as endpoint. Patients with a single tumor, either left or right, showed a better outcome in terms of survival in comparison with MPN (HR: 0.87, IC: 0.79 - 0.96, for right BC and HR: 0.88, IC: 0.79 - 0.96, for left BC).

Conclusões

In light of our research findings, we observed MPN breast cancer as a risk factor for mortality in comparison with a single tumor. About epidemiological factors, former drinkers and smokers were related to worst survival in both single tumor and MPN patients.

Financiador do resumo

Grant 313797/2023-4 National Council for Scientific and Technological Development (CNPq), Precision Health support for LRCB.

Palavras Chave

Data analysis; Epidemiology; Breast Neoplasms