Factors Predicting the Outcome of BCG (Bacillus Calmette-Guerin) Therapy

Abstract

Background: Bacillus Calmette-Guerin is currently con­sidered to be the gold standard in conservative treatment for intermediate and high risk non-muscle invasive blad­der cancer (NMIBC). However, up to 40% of the patients, treated with adjuvant BCG therapy, experience failure. As the new methods of treatment after BCG failure ap­pear, there is a need to assess efficacy of this therapy in order to improve appropriate treatment during or before BCG therapy. Aim: To review the latest studies on factors, predicting BCG efficacy, and provide summarized information re­garding treatment outcomes in current practice. Methodology: The search was conducted in MEDLINE (Pubmed) and ScienceDirect databases using predeter­mined keywords: Bacillus Calmette-Guerin (BCG), fai­lure, intravesical therapy, outcome, response, predicting factors, immunological markers, efficacy. 10 articles pu­blished since 2017 were included in this literature review. Results: Prognostic factors such as the use of antibiotics prior to the therapy, body mass index (BMI), lympho­vascular invasion (LVI), endothelin-1 (ET-1), tumor substaging, CD4/CD8, GATA3/T-bet, CD163/CD68, neu­trophil-to-lymphocyte (NLR) ratios are promising factors for estimating the possible response of BCG therapy be­fore undergoing treatment. Blood eosinophil count and percentage, FISH test following 3 months after first BCG instillation and a Cytokine Panel for Response to Intrave­sical Therapy (CyPRIT) nomogram showed huge poten­tial for predicting BCG outcome during BCG treatment. Conclusion: There are quite many possible clinicopatho­logic, immunological, immunohistochemical and anam­nestical factors that could predict the success of BCG therapy. However, in order to include prognostic fac­tors in treatment guidelines, further studies should be performed to determine which of these factors have the greatest clinical value.