Novel test for bladder cancer is based on urine sediment

Bladder cancer is the sixth most common tumor diagnosis in the EU and up to 70% of tumors develop recurrences within a year. Early detection is a major problem. A new urine test could improve screening.

MCM5 antibodies detect bladder cancer

Bladder cancer is the sixth most common tumor diagnosis in the EU and up to 70% of tumors develop recurrences within a year. Early detection is still a major problem. A new urine test could improve screening in the future.

In the prelude to this year's EAU Congress, British researchers presented a very exciting new test for bladder cancer from urine sediment. In their pharma-funded study, the scientific team led by Tim Dudderidge used so-called MCM5 antibodies, which detect MCM5, a protein that occurs in dividing cells.

The trick: The differentiated cells of the bladder epithelium are normally not active during division and therefore do not produce MCM5. For this reason, healthy people do not have MCM5 in their urine, whereas cancer patients do.

High detection rates are shown

The current prospective study included a total of 856 patients from seven centers in the UK who had visited physicians due to unexplained haematuria. The clinical data and final diagnoses of the participants were compared with cystoscopic and imaging data. The prevalence of bladder carcinoma in the study group was 8.6%.

The new MCM5 test reliably detected 54 of a total of 74 tumors, corresponding to a sensitivity of 73%. The "overall negative predictive value" (NPV) was 96.4%. Sensitivity and NPV increased to 100% when the patients suffered from an already muscle-invasive bladder tumor.

Of the 173 patients with cytology, 18 were later identified as tumor patients. With the help of the novel MCM5 test, 16 of these 18 cases could also be identified. In the cytological examination, however, this was only possible in 4 of the 18 patients.

Conclusion

Bladder carcinoma is a tumor that is often problematic in early detection. The current study once again shows that cytology alone is often not sensitive enough to make a reliable early diagnosis. The presented test for MCM5 seems to improve this situation significantly and could, therefore, be a possible more sensitive alternative or a good supplement to classical cytology.

Original publication:
Dudderidge T et al, Eur Urol Oncol 2020; 3: 42-46