Prognostic factors associated with locoronal relapses, metastatic relapses, and death among women with breast cancer. Population-based cohort study.

BACKGROUND

This study was designed to identify the prognostic factors associated with two types of relapses of breast neoplasms. The aim of this study was to evaluate the association between two possible relapses for the increased incidence of distant metastases observed in patients with local relapses injuries, using multivariate statistical models.

DESIGN

And Setting: A population-based cohort study that was designed as a single center: the cancer research center, Shahid Beheshti University of medical sciences.

METHODS

This study was conducted on 1815 patients with breast cancer having age of 22 or more. This study considers the analysis of recurrence and survival by joint modeling of three correlated outcomes: local recurrence, distant recurrence (metastasis) and death. The goals are to find out the effects of treatments on recurrences and death, the effects of relapses on death and the correlation between local and distant recurrences.

RESULTS

According to obtained results of the fitted models, the risk of local and metastatic relapses or death increased for patients with at least one positive lymph node (N+) or for patients with a grade greater than I. Also, the variable HR+ was significantly associated with the hazards of locoronal, metastatic recurrence and the death for both reduced and proposed models (P < 0.05).

CONCLUSIONS

We concluded that if the association between these outcomes are not taken into account, we may lose important information. Given the small number of recurrent events, these results should be considered with caution.