Radiological case of the month: Manzar H. Rizvi, MD; Timothy J. Murphy, MD; Yashodeep P. Jadhav, MD.
A 46-year-old man, father of 3 children, was referred for evaluation of a left testicular mass. He had noticed the mass approximately 1 month previously but did not have any discomfort. On clinical examination, the left hemiscrotum contained 2 masses. Both masses did not transilluminate and were nontender. A normal-appearing right testicle was easily palpable in the right hemiscrotum. The patient denied any history of trauma or scrotal disease. Medical history was significant for a left herniorraphy. Results of laboratory studies were within normal limits. Ultrasound imaging was performed (Figure 1).
[FIGURE 1 OMITTED]
Testicular ultrasound revealed 2 testicles in the left hemiscrotum and a single testis in the right hemiscrotum (Figure 1). The echotexture of all 3 testes was the same. The upper testis on the left measured 2.5 x 2.1 x 2.2 cm, and the lower measured 2.6 x 2.3 x 1.9 cm. The normal right testis measured 4.3 x 2.2 x 2.4 cm. A hypoecohic area was seen in the lower testicle on the left, which raised a concern of a neoplasm. The patient underwent a left orchiectomy. At surgical exploration, the contents of the tunica vaginalis revealed 2 structures with the appearance of testicles. These were conjoined by a single epididymis and led to a single vas deferens. The patient was also noted to have a scar from the previous left herniorraphy.
At gross pathology, both testicles were white-pink/ tan in color with a smooth and glistening surface. The parenchyma had tubules that strung with ease. Spermatogenesis was seen in both testicles and no masses or neoplasm were identified. On re-examination of the preoperative ultrasound, the focal hypoechoic area seen in the lower testis was believed to represent ectasia of the rete testis.
There is a discrepancy in the number of reported cases of polyorchidism. Apparently, <100 cases have been reported to date. (1) In 1880, Ahlfeld (2) reported the first histologically confirmed description of polyorchidism. Arbuthnot Lane (3) reported the first case found at surgery in 1895.
There is a striking preponderance for polyorchidism to occur on the left side, as is demonstrated in this case. In 75% of reported cases, the supernumerary testis was present on the left. The most common relationship between the 2 ipsilateral testicles is a proximal and distal arrangement; the distal testis is typically larger and has a more typical morphology. The reported locations include scrotal (75%), inguinal (20%), and retroperitoneal (5%). (4) The majority of reported cases note triorchidism, and, occasionally, bilateral duplication has been reported. One patient with 5 testes was reported, although it was not confirmed histologically. (5) Hakami and Mosavy (6) reported an interesting case of triorchidism as an "unusual cause for failure of vasectomy." (6) The patient's wife became pregnant despite his bilateral vasectomy. Evaluation of the patient revealed a supernumerary testis in the right hemiscrotum with an intact vas, a normal histology, and spermatogenesis. Only 1 of the 2 vasa had been resected during the vasectomy.
[FIGURE 2 OMITTED]
Several theories have been proposed to explain testicular duplication, including division of the gonadal ridge and degeneration of parts of the mesonephric duct. At approximately 8 weeks of fetal gestation, the testis forms from the urogenital ridge by the condensation of a longitudinal cell mass opposite the middle third of the mesonephros. The epididymis and vas deferens are formed from the mesonephric duct. The development of an extra testicle can occur when the testicular fundament separates into [greater than or equal to] 2 segments. Since the primitive gonadal ridge is an elongated structure, transverse fragmentation can take place and extend onto the mesonephric duct. This would explain the inequality of the 2 testes and account for variants in which both are joined by a common epididymis, or in which 1 is detached from the outflow path. Complete separation of the testes and drainage system requires duplication of both the genital ridge and the mesonephric duct.
The extent and locus of the division determine the different types of polyorchidism. As described by Leung, (7) the various types possible on an embryological basis (Figure 2) are as follows:
* Type I: Supernumerary testis lacks an epididymis or vas and is not attached to the lower testis. This can occur if the division separates from only a small part of the genital ridge that is not in contact with the rete testis.
* Type II: The supernumerary testis has its own epididymis but shares a common vas with the lower testis. This can occur if there is complete transverse division through the genital ridge and the mesonephros.
* Type III: Both testes share a common epididymis and a common vas. This may result if the division of the genital ridge does not include the mesonephros.
* Type IV: Complete duplication of the testis, epididymis, and vas. This form is the rarest and may result from simultaneous duplication of the genital ridge and mesonephric duct (Figure 2). Singer et al8 have suggested an anatomic and functional classification of polyorchidism:
* Type I: The supernumerary testis has reproductive potential and is connected to a draining epididymis and vas.
* Type II: The supernumerary testis lacks reproductive potential and the testis is without any attachment to the epididymis and vas.
These were further divided, by location, into types A (scrotal) and B (extrascrotal). A management strategy was proposed depending on the type.
Patient age at presentation varies from 4 weeks to 75 years. (4) In the majority of cases, the patients are asymptomatic and present with a painless groin or scrotal mass. The external sexual characteristics are invariably normal. The 2 most common anomalies associated with polyorchidism are maldescent (40%) of either the supernumerary testis or the ipsilateral (more normal) testis and indirect inguinal hernia (30%). (9) The patient we describe here had previously undergone a herniorraphy. Other associations noted with polyorchidism are torsion (13%), hydrocele (9%), and dysplasia or neoplasm (6%). (9) The incidence of cancer in patients with polyorchidism is higher than would be expected on the basis of maldescent alone. Other reported complications include epididymitis, varicocele, and infertility. Normal spermatogenesis is usually absent in the majority of supernumerary testes.
Management of polyorchidism depends on multiple factors. The location of the testis, whether scrotal or ectopic in the inguinal canal or retroperitoneum, its reproductive potential, the size and volume of the testis, and the age of the patient should be taken into account. A conservative approach is recommended when dealing with a child or young adult, with the goal of preserving the supernumerary testis, unless orchiectomy is indicated for a suspected mass or if the testis is atrophic. This is important not only in terms of fertility but also in regard to the psychological impact on the child. In an adult, even if the supernumerary testis is orthotopic and normal in function, removal should be considered because of an increased risk of malignancy. The risk of malignancy is a strong argument for excision of the supernumerary testes; however, the potential for spermatogenesis is the best reason for preservation.
(1.) Khetan N, Torkington J, Jamison MH. Polyorchidism presenting as retractile testis. BJU Int. 1999;83:524.
(2.) Ahlfeld F. Die Missbildungen des Menschen. Leipzig, Germany: Grunow; 1880:126.
(3.) Lane A. A case of supernumerary testes. Trans Clin Soc Land. 1895; 28:59.
(4.) Thum G. Polyorchidism: Case report and review of literature. J Urol. 1991;145:370-372.
(5.) Day GH. One man with five testes: Report of case. JAMA. 1918;71: 2055-2056.
(6.) Hakami M, Mosavy SH. Triorchidism with normal spermatogenesis: An unusual cause for failure of vasectomy. Br J Surg. 1975;62:633.
(7.) Leung AK. Polyorchidism. Am Fam Physician. 1988;38:153-156.
(8.) Singer BR, Donaldson JG, Jackson DS. Polyorchidism: Functional classification and management strtegy. Urology. 1992;39:384-388.
(9.) Sharma AK, Mathur P. Polyorchidism. Pediatr Surg Int. 1994;9:531.
Prepared by Manzar H. Rizvi,MD, Staff Radiologist, St. Luke's-Roosevelt Hospital, New York, NY; Timothy J. Murphy, MD, Staff Radiologist, Geisinger Medical Center, Danville, PA; Yashodeep Jadhav, MD, Staff Radiologist, Imaging Division, Olin E.Teague Veteran's Center, Temple, TX.
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|Author:||Rizvi, Manzar H.; Murphy, Timothy J.; Jadhav, Yashodeep P.|
|Article Type:||Clinical report|
|Date:||May 1, 2006|
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