BRCA testing in metastatic castration-resistant prostate cancer: successes and troubles in a real world setting. An Italian Multicentric study.

OBJECTIVE

Prostate cancer (PCa) is the most common cause of cancer-related deaths in men worldwide. BRCA1/2 genes are reported altered in approximately 1% and 8% of PCa cases, respectively. To date, formalin-fixed paraffin-embedded (FFPE) tissues have a consolidate use in the clinical practice, but with a significant drawback related to DNA/RNA degradation during the pre-analytical process. The purpose of this study is to evaluate the feasibility of detecting BRCA1/2 alterations in DNA extracted from FFPE tissues collected from PCa patients after various years of storage in seven Italian hospitals.

METHODS

A total of 241 DNA samples were extracted from FFPE tissue with different storage times (1-12 y) and sequenced with NGS technology. BRCA1/2 evaluability was assessed performing data analysis with a chi-square test to study the impact of the storage time on the DNA degradation.

RESULTS

The data collected showed a strict relation not only between the storage time and the BRCA1/2 evaluability, but even between the storage time and DNA degradation (DIN). Taken together, all the parameters considered decrease with an increase in the storage time.

CONCLUSIONS

Excessive FFPE tissues storage time (more than 3 years) can harshly affect DNA analysis and evaluability, hindering the achievement of a result useful in the clinical practice. Hence, it should be considered to perform the analysis as soon as possible to increase the evaluability of the test.