Spermatocele
Spermatocele is a benign, sperm-containing cystic dilation of the epididymal duct or rete testis, palpated as a painless, mobile, fluctuant paratesticular nodule that transilluminates and appears as an anechoic extratesticular lesion on scrotal ultrasound; asymptomatic spermatoceles require no treatment, while large or painful ones are managed with surgical excision.
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What this article covers
- Overview
Definition: a spermatocele is a benign, sperm-containing cystic dilation of the epididymal duct or rete testis, arising as an outpouching from the epididymal tubule.
- Epidemiology
Common incidental finding on scrotal exam or ultrasound, frequently discovered during a routine physical, a fertility evaluation, or imaging obtained for an unrelated scrotal complaint.
- Risk factors
Prior epididymitis or epididymal inflammation, which can lead to focal tubular obstruction and cyst formation.
- Pathophysiology
Focal obstruction or dilation of the epididymal duct, or the efferent ductules of the rete testis, allows fluid and sperm to accumulate, forming a cystic outpouching proximal to the point of obstruction.
- Clinical features
A painless, mobile, fluctuant nodule palpated separate from and superior/posterior to the testis, most often at the head of the epididymis, is the hallmark finding.
- Differential diagnosis
Testicular tumor: a firm, non-tender, non-mobile, solid intratesticular mass that does not transilluminate, the diagnosis that must never be missed; ultrasound shows a hypoechoic intratesticular…
- Diagnosis
The diagnosis is established clinically by a painless, mobile, fluctuant paratesticular nodule that transilluminates on exam, with the testis itself palpating normally and separately from the mass…
- Management
First, confirm the mass is a simple, asymptomatic spermatocele on exam or ultrasound, since the large majority require no treatment beyond reassurance.
- Complications
Epididymal scarring and potential impairment of sperm transport after surgical excision, the main procedural risk that argues for observation whenever the spermatocele is asymptomatic.
- Prognosis
Excellent: spermatoceles are benign and do not undergo malignant transformation.
- Prevention
There is no established primary prevention for spermatocele, since the cause is degenerative ductal dilation rather than a modifiable exposure.
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