Enhanced nodal staging by molecular detection of KLK3, FOLH1, and PCA3 in prostate cancer

To study the expression of KLK3, FOLH1, and PCA3 in pelvic lymph nodes of prostate cancer (PCa) patients and the relationship between molecular level detection of lymph nodes and biochemical recurrence (BCR).

A retrospective selection of 26 PCa patients with mediate and high risk undergoing radical prostatectomy combined with pelvic lymph node dissection in the same treatment group of the Department of Urology, Beijing Chaoyang Hospital from April 2021 to August 2022. The expression of prostate cancer-specific molecular biomarkers KLK3, FOLH1, and PCA3 in 59 lymph nodes were detected by polymerase chain reaction (PCR), and 11 pelvic lymph nodes from 7 patients undergoing radical cystectomy were used as controls. The threshold was determined based on the average relative expression of each gene. The biochemical recurrence-free survival (BRFS) was determined through postoperative follow-up, and the Kaplan-Meier survival curve was used to compare the BRFS of different lymph node metastasis (LNM) levels (pN0molN0, pN0molN1, pN1molN1).

A total of 59 lymph nodes obtained from 26 patients were tested. Histopathological examination before the experiment confirmed that 10 patients had LNM. PCR molecular analysis confirmed that in 10 metastatic lymph nodes (pN1molN1) of 10 patients with LNM, the expression of KLK3, FOLH1, and PCA3 genes increased. Of the 26 patients, 5 had BCR. Molecular lymph node analysis can improve the sensitivity of predicting BCR compared to pathological diagnosis. The level of LNM is related to the patient's BRFS.

PCR analysis of KLK3, FOLH1, and PCA3 expression enables the molecular detection of lymph-node metastasis and, when combined with standard histopathological examination, improves the accuracy and sensitivity of lymph-node staging. It also refines risk stratification for postoperative BCR, particularly by identifying pathologically node-negative patients at increased risk. Molecular lymph-node assessment based on these markers may therefore serve as a useful prognostic tool to guide adjuvant treatment decisions, although larger prospective studies are needed to validate these findings.