Sentinel lymph node biopsy in bladder cancer: Systematic review and technology update

Area of Science:

• Uro-oncology
• Surgical oncology
• Diagnostic imaging

Background:

• Sentinel lymph node (SLN) biopsy is a standard staging tool for melanoma and breast cancer.
• Its role in urothelial carcinoma of the bladder remains under investigation.
• SLNs are the initial lymph nodes to receive drainage from a solid tumor.

Purpose of the Study:

• To systematically review the utility of SLN detection in urothelial carcinoma of the bladder.
• To assess the accuracy of SLN biopsy in predicting metastasis.
• To identify areas for improvement in SLN biopsy techniques for bladder cancer.

Main Methods:

• Systematic literature search of PubMed for human and animal studies on SLN detection in bladder cancer.
• Analysis of identified studies assessing various imaging techniques for SLN identification.
• Evaluation of reported negative and positive predictive values and false negative rates.

Main Results:

• Nine studies (8 human, 1 animal) met the inclusion criteria.
• The overall negative predictive value of SLN biopsy was 92% (92/100) for predicting a metastasis-free state.
• The positive predictive value was 77% (43/56), with a false negative rate ranging from 0-19%.

Conclusions:

• SLN biopsy is a promising concept for bladder cancer staging with a high negative predictive value.
• High false negative rates indicate a need for standardization of patient populations and indications.
• Advancements in detection technologies may improve micrometastasis identification and surgical guidance, potentially reducing patient morbidity.