Microsatellite instability profiling in Egyptian bladder cancer patients: A pilot study

Area of Science:

• Oncology
• Genetics
• Urology

Background:

• Microsatellite alterations are crucial in cancer development but understudied in Egyptian bladder cancer (BC) patients.
• Assessing microsatellite instability (MSI) and loss of heterozygosity (LOH) provides insights into BC pathogenesis.

Purpose of the Study:

• To evaluate the MSI profile and LOH in Egyptian BC patients using tumor tissue and urine samples.
• To determine the concordance of MSI between tissue and urine, and correlate findings with clinicopathologic features.

Main Methods:

• Analyzed 13 microsatellite markers in tumor tissue and urine sediments from 30 Egyptian BC patients.
• Assessed microsatellite instability (MSI) and loss of heterozygosity (LOH).
• Correlated MSI/LOH data with clinicopathologic features and determined concordance between sample types.

Main Results:

• MSI was universally detected (100%), while LOH occurred in 46.7% of cases.
• Specific markers like D16S310, MBP, and IFN-α showed high MSI frequency in urine; MBP, ACTBP2, and D9S171 in tissues.
• MSI correlated significantly with tumor type (transitional cell carcinoma) and hematuria. Concordance between tissue and urine was significant for D16S476, D9S171, FGA, and ACTBP2.
• Combined D16S476 and D9S171 markers achieved 80% sensitivity and 75% specificity for BC diagnosis.

Conclusions:

• Microsatellite instability (MSI) analysis in urine sediments represents a viable, non-invasive approach for bladder cancer (BC) diagnosis.
• The high concordance and diagnostic accuracy suggest urine-based MSI testing could complement existing BC diagnostic methods.