Objective: To investigate the value of laparoscopy in boys with impalpable testes, to carry out a histological examination of testicular biopsies or orchidectomy specimens, and to present a clinical description of boys with impalpable testes.
Patients and methods: One hundred consecutive patients underwent laparoscopy for 128 impalpable testes. They ranged in age from 2.7 to 19.3 years (median 10.8). Histological examination was performed on 39 testicular biopsies, nine primarily orchidectomized testes and 13 tissue samples from the end of blind-ending vessels and vasa deferentia. Any additional diagnoses to that of impalpable testes were recorded.
Results: There were no complications associated with laparoscopy and the procedure clarified the situation in all patients. In 50% of patients either blind-ending cord structures above the internal inguinal ring or intra-abdominal testes were identified; in the remainder, cord structures could be seen passing through the ring, indicating an intracanalicular testis. The impalpable testis was absent in 77% of patients with a contralateral scrotal testis. A seminoma was found in one 18.6-year-old patient with bilateral cryptorchidism. No intratubular germ cell neoplasia (carcinoma in situ) was found. Germ cell hypoplasia or aplasia was demonstrated in 95% of patients with testicular parenchyma. Additional diagnoses were made in 49% of patients with bilaterally undescended testes (one or both of which were impalpable).
Conclusion: We recommend laparoscopy as a safe procedure which leads to a diagnosis in patients with impalpable testes; the advent of laparoscopic procedures makes definitive treatment possible in about 50% of such patients. Open procedures will be indicated only to ascertain the quality and treatment of intracanalicular testes.