ASSOCIATION OF PRE-TREATMENT BLOOD TRANSFUSION WITH CERVICAL CANCER OUTCOMES: A SYSTEMATIC REVIEW AND META-ANALYSIS

Abstract

Introduction: Cervical cancer (CC) is one of the leading causes of cancer-related deaths in low- and middle-income countries, where it is often diagnosed as symptomatic, which is common in advanced stages. The most common symptom of CC is vaginal bleeding, which can lead to anemia and an indication of blood transfusions (BT) before initiating cancer treatment. However, the implication of BT in the survival of patients with CC remains unclear. Objective: We conducted a systematic review and meta-analysis that investigated the association between BT and survival outcomes in patients with CC. Methodology: A systematic search of the PubMed, Embase, and Cochrane databases was conducted in July 2024. The search strategy employed the MeSH terms: “cervical cancer” AND “blood transfusion.” Inclusion criteria were (1) articles reporting on CC patients who received blood transfusions before curative treatment (2) report of disease-free survival (DFS) and overall survival (OS) as main outcomes. Exclusion criteria included (1) reviews, (2) case reports (3) BT after or during oncology treatment. Data extraction and quality assessment were performed independently by two reviewers. Hazard ratios (HR) for DFS and OS were calculated using a random-effects model, with heterogeneity assessed using the I2 metric and Cochran's Q test in Review Manager 5.4 software. Results: The initial search yielded 723 articles, of which 3 met the inclusion criteria and were included in this review. These studies encompassed 1301 patients, of whom 492 (37.8%) received BT before their curative therapy, which was chemoradiation. The analysis demonstrated that patients who received BT had a worse prognosis, with an HR of 2.78 for OS (95% CI 1.27-6.11; p = 0.01; I2 = 0%). An analysis with 2 studies demonstrated an HR of 2.55 for DFS (95% CI 1.41-4.62; p = 0.01; I2 = 0%). Discussion: Our findings demonstrate that in patients with CC, pre-treatment BT is associated with noticeably poorer OS and DFS. This result suggests that BT is a poor predictor of survival outcomes. There are numerous possible explanations for this correlation. Given that BT is known to cause immunosuppression, tumor development and metastasis may be encouraged. Furthermore, pro-inflammatory mediators that may be present in BT may further contribute to an unfavorable tumor microenvironment. Although these elements were not examined in our analysis, additional variables including the length of time blood products are stored or the existence of particular blood groups may potentially be important. Conclusion: Our findings suggest that pre-treatment blood transfusion is associated with significantly worse OS and DFS in cervical cancer patients. These results highlight the need for further prospective research to confirm this association, as well as to explore alternative strategies to manage anemia and cancer-related blood loss in this population, promoting personalized treatment strategies that optimize outcomes for women with cervical cancer.