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.
