To identify independent predictors of germ cell remnants in unilateral nodular testis and provide evidence for intraoperative decision-making (exploration vs. termination) during laparoscopy.

A retrospective cohort of 194 children who underwent unilateral nodular testis resection from November 2017 to December 2023 was analyzed. Data included clinical parameters (age, affected side, BMI), ultrasonographic measurements (nodular testis length, contralateral testis length), serum follicle-stimulating hormone (FSH), and intraoperative anatomical features (status of the internal inguinal ring, spermatic vessels and vas deferens). Univariate and multivariate logistic regression analyses were performed to assess the risk factors for the presence of germ cells in nodular testes.

Germ cells were pathologically confirmed in 21 cases (10.8%), suggesting indicating potential germ cell tumor risk. The right-sided nodular testis showed a higher germ cell detection rate (16.7% vs. 8.9%, P=0.13), though statistically insignificant. Multivariate analysis identified the open internal inguinal ring (OR=4.66,95%CI:1.56–13.95, P=0.006) and undescended vas deferens (OR=5.39,95%CI:1.18–24.66, P=0.030) as independent risk factors for germ cell remnants. Status of Spermatic vessels and FSH levels showed no significant association. Among 3 cases with a closed internal ring and non-descent of both spermatic vessels and vas deferens, germ cells were detected in 1 case (33.3%).

Laparoscopic findings of an open internal ring or non-descent of the vas deferens warrant further exploration in nodular testis. However, the safety of terminating exploration for cases with a closed internal ring and blind-ending spermatic vessels/vas deferens requires further investigation.