Testicular and paratesticular pathology in infants and children: the histopathological experience of a tertiary paediatric unit over a 17 year period.

To examine the pathological features of paediatric testicular and paratesticular lesions from a tertiary referral centre and describe their relative pathological frequency, highlighting relevant epidemiological and histopathological findings. A search was made of a computerised histopathology database covering the period from 1988 to 2004 inclusive to identify cases of testicular and paratesticular pathologies, and the clinical and histopathological features reviewed. Five hundred and fifty-one appropriate specimens underwent histological examination during the period. Three hundred and eleven (56%) presented with an impalpable testis with or without intersex disorder and 121 (22%) with a testicular/paratesticular mass. While metastatic leukaemic testicular involvement (N = 47) was the commonest tumour identified in this preselected series, at a peak of 8 years, primary testicular tumours such as yolk sac and teratoma were most commonly identified in infancy. Of 109 (20%) presenting with an acutely painful scrotum, the largest group (47%) represented torsion of the appendix testis. The vast majority of pathological samples arose from children less than 4 years of age in accordance with the predominance of cryptorchidism, 'vanished' testis, neonatal torsion and testicular tumours in this age group. The findings of this study demonstrate the spectrum of testicular pathology in childhood. Neoplasms represented >20% of the pathology, but the largest clinical group of pathological specimens in this patient population is associated with clinically impalpable or the palpably abnormal testis.