Rapid Clearance of microRNA-371a-3p: A Longitudinal Study of Serum Levels in Patients with Localized Testicular Germ Cell Tumors.

BACKGROUND AND

OBJECTIVE

Rapid clearance after treatment is a cornerstone feature of valuable tumor markers. microRNA-371a-3p (M371) has much promise to become a useful biomarker of germ cell tumors (GCTs). However, little is known about its velocity of decay. This study aimed to systematically analyze the kinetics of decline of M371 serum levels.

METHODS

A total of 53 patients with clinical stage (CS) I GCT had measurements of M371 levels before orchiectomy and five measurements postoperatively, four within the first 48 h, and one after 2 wk. The commercial M371 test was used to measure serum levels with quantitative polymerase chain reaction. Postoperative levels were statistically compared with the preoperative level. The half-life (H/L) and the absolute time to normalization (TTN) were calculated by linear interpolation. Possible associations with clinical factors were evaluated.

KEY FINDINGS AND LIMITATIONS: The median H/L of M371 was 3.8 h (interquartile range [IQR] 2.9-6.2). We found no statistical evidence that H/L was associated with the clinical factors evaluated. The absolute median TTN was 33.8 h (IQR 6.5-261.6), which was associated with the baseline value of M371. Limitations may result from baseline blood sampling several days before surgery.

CONCLUSIONS AND CLINICAL IMPLICATIONS: M371 levels in patients with CS I GCT decline with a H/L of 3.8 h postoperatively, which is much more rapid than in traditional markers. The absolute TTN of M371 is associated with the baseline value and exhibits interindividual variability. Overall, the rapid kinetic profile of M371 is another valuable feature of the novel biomarker of testicular GCTs.