The spectrum of testicular-epididymal fusion anomalies in children with cryptorchidism: Personal experience, systematic review and meta-analysis.
BACKGROUND
Testicular-epididymal fusion anomalies (TEFA) have been documented in the literature. The pathological significance of TEFA and their relationship to testicular maldescent is unclear. We aimed to clarify the real incidence of TEFA in children with undescended testes and their impact on testicular development after surgery.


METHODS
We conducted a retrospective review (2010-2018) of all patients who underwent orchidopexy. Cases with TEFA confirmed intra-operatively were matched against controls with normal fusion for age at the time of surgery. Records from follow-up visits were assessed to compare testicular size at six-months. A systematic review and meta-analysis of the literature (1980-2019) was also performed.


RESULTS
In our retrospective review, 54 (21.4%) of 252 cryptorchid testes were found to have TEFA (Table). Intra-abdominal testes were more likely to exhibit TEFA than inguinal testes (20.4% vs. 9.6%, RR 1.8 [1.0-3.1], P = 0.03). There were no differences in testicular size at the time of surgery (P = 0.29) or the six-month followup (P = 0.18). The systematic review identified eight studies with 4871 children (5240 orchidopexies). The overall rate of TEFA was 25.8% [95% CI 15.2-38.0]. Tail nonfusion (NF) (10.7% [95% CI 5.4-17.4]) was the most common followed by head NF (7.2% [95% CI 3.2-12.5]) and complete NF (6.3% [95% CI 3.7-9.5]). Intra-abdominal testes were more likely to exhibit TEFA than inguinal testes RR 2.6 [95% CI 1.9-3.5]; P < 0.001.


CONCLUSIONS
Data from our retrospective review and the literature indicate that TEFA are present in approximately one-quarter of cryptorchid testes and are more commonly associated with intra-abdominal cryptorchidism. There appears to be no impact on testicular size at short-term followup. The clinical significance of TEFA remains unclear; long-term followup studies are necessary to better understand their impact on testicular development and function.