25P - Absolute lymphocyte count as prognostic factor in patients with metastatic breast cancer: A systematic review and meta-analysis

Background

Breast cancer is the second most common cancer worldwide. Some studies have begun investigation of Absolute Lymphocyte Count (ALC) to predict prognosis of breast metastasis. This review aims to analyze use of ALC to predict overall survival (OS) in breast metastasis patients.

Methods

A total of 73,233 literatures were found through PubMed, PMC, Science Direct, and Google Scholar using a combination of keywords including ALC, breast metastasis, and OS. Publications included are limited to English manuscripts published within the last ten years. We excluded publications with insufficient datas and non-breast metastatic studies. Studies were evaluated by all four authors using the Newcastle-Ottawa Scale (NOS), JADAD scale, funnel plot to assess publication bias, and Grading of Recommendations, Assessment, Development, and Evaluation (GRADE) to assess quality of this review.

Results

A total of 11 studies consisting 2,433 patients were included in this review. Nine retrospective studies were of good quality using NOS, two clinical trial studies were of low quality using JADAD scale. GRADE assessment revealed this review to be moderate in quality and publication biases are minimal. Most studies revealed an association between low ALC or lymphopenia and worse prognosis, while 1 study showed otherwise. A pooled analysis of hazard ratio (HR) from log-rank test (HR = 0.57; 95% CI, 0.46-0.71; P = 0.52), univariate cox regression analysis (HR = 0.69; 95%CI, 0.61-0.78; P = 0.01) and multivariate cox regression analysis (HR = 0.70; 95%CI, 0.60-0.81; P = 0.30) showed minimal correlation.

Conclusions

While most studies used in this review showed strong correlation between low ALC and OS with statistically significant results, pooled analysis from this review revealed only the univariate cox regression analysis of HR showed statistically significant results. We conclude that lymphopenia may affect OS in patients with metastatic breast cancer. Further studies are required, especially high quality clinical trials.

Clinical trial identification

Editorial acknowledgement

Legal entity responsible for the study

The authors.

Funding

Has not received any funding.

Disclosure

All authors have declared no conflicts of interest.