An epididymal cyst is a benign cystic lesion that can develop anywhere along the epididymis. According to the literature, the incidence of epididymal cysts in pediatric populations ranges from 5% to 20% (1, 2). In post-pubertal adolescents, a cyst located specifically in the caput (head) that contains spermatozoa is termed a spermatocele; both entities, however, share similar clinical implications and management considerations. This condition typically lacks specific clinical symptoms, and most cases are incidentally detected during routine testicular ultrasound examinations (3). A minority of patients present with a palpable scrotal mass, which may exhibit positive translucency on examination, often leading to confusion with hydrocele. Larger cysts pose a risk of torsion (4), and patients experiencing ipsilateral scrotal pain may be misdiagnosed with conditions such as epididymitis, orchitis, or other scrotal disorders, potentially delaying appropriate treatment (5). Therefore, accurate diagnosis is critical for optimal patient outcomes. This study retrospectively analyzed three cases of adolescent epididymal cysts treated at our institution and reviewed relevant literature. This review aims to summarize the clinical features and management strategies for epididymal cysts in adolescents, thereby enhancing pediatric surgeons’ understanding of this condition, reducing diagnostic errors and complications, and guiding personalized treatment approaches for affected children.

Epididymal cysts (EC) are fluid-filled cystic masses located in the epididymis (6). The exact etiology remains unclear, although some studies suggest a potential link to hormonal imbalances during embryonic development, positioning epididymal cysts as a congenital anomaly (2, 7). Furthermore, maternal intake of hormonal disruptors such as diethylstilbestrol during pregnancy has been associated with an increased risk of fetal epididymal cysts (8). Environmental endocrine disruptors and obstruction of the vas deferens or epididymal duct may also contribute to the formation of epididymal cysts in children (2, 9). Some literature even suggests that epididymal cysts might be a manifestation of testicular hypoplasia syndrome (10–12). Interestingly, patients with epididymal cysts often present with a larger testicular volume on the affected side compared to individuals without such cysts (2, 13).

In children, the incidence of epididymal cysts is reported to range from 5% to 20%, with an increasing prevalence as age advances (2). Approximately 20%–30% of epididymal cysts are detected incidentally during routine physical examinations and confirmed by scrotal ultrasound. Smaller cysts may be asymptomatic and challenging to detect, with up to 70%–80% of cases remaining unnoticed (6, 13, 14). For instance, case 1 and case 2 presented in this report had no significant clinical symptoms. While epididymal cysts and spermatoceles are often considered the same disease in many studies, there are notable differences (6, 15). An epididymal cyst is a broad term referring to cysts typically seen in prepubertal individuals. These cysts are located anywhere within the epididymis and contain serous fluid without sperm. On the other hand, spermatoceles are more commonly seen post-puberty, typically located in the head of the epididymis. The fluid within spermatocele is more viscous, containing non-motile sperm and cellular debris (15). Spermatoceles are thus considered a specific subtype of epididymal cysts (8, 15, 16). Both types of cysts appear as anechoic or hypoechoic masses on ultrasound, with thin walls and occasional septations (14). Differentiation between the two may be achieved by cyst fluid aspiration to assess the presence of sperm (16).

In most cases, epididymal cysts are asymptomatic, and scrotal pain is minimal or absent. It is reported that 60% of cysts, especially those smaller than 3 cm, may slowly degenerate over time (17). Some studies suggest that conservative management with periodic follow-up may be appropriate for asymptomatic patients without significant growth of the cysts (18). However, cysts may occasionally be confused with hydroceles due to their similar presentation on physical examination, including positive translucency. Ultrasound plays a crucial role in the definitive diagnosis, as it can clearly delineate the size, location, and characteristics of the cyst, including the presence of blood flow signals, septations, and echo strength (1, 9). Epididymal cysts are typically located in the head of epididymis, appearing as round anechoic or hypoechoic areas with smooth walls and posterior acoustic enhancement, and they cannot be separated from the epididymis (7, 14). Hydroceles, in contrast, are typically located above the testis or within the spermatic cord and manifest as fluid collections in the peritesticular space. Although ultrasound can distinguish the two conditions in most cases, in certain instances, the differentiation may not be straightforward, as seen in case 1 where ultrasound could not definitively distinguish between a hydrocele and spermatocele. This was clarified by cyst aspiration.

Various treatment options exist for epididymal cysts, including conservative observation, sclerosing agent injections (e.g., phenol, ethanolamine oleate, tetracycline), cyst fluid aspiration, and surgical intervention (19–23). Small cysts (less than 10 mm) are typically managed conservatively, while larger cysts, or those that cause symptoms, may warrant surgery (7). Cyst fluid aspiration and sclerosing agent injection are minimally invasive alternatives that can be performed under local anesthesia in the outpatient setting. These options are less expensive and technically simpler than surgery but may require multiple treatments to achieve satisfactory results (24). Surgical intervention is generally recommended for large, symptomatic cysts, with the goal of complete cyst removal (7, 18), as in our case 2. However, surgery must be performed with meticulous care, particularly in separating the cyst from the epididymis to avoid damage to the epididymis and its blood supply. Surgical removal of the cyst is generally not recommended for patients with fertility concerns due to the risk of damaging the epididymis or causing scar tissue that may lead to fertility issues, particularly in cases involving bilateral cysts (7, 25). In our case 1, cyst aspiration was performed first, with the decision to proceed to surgery reserved for follow-up based on the cyst's behavior. Postoperative complications may include scrotal edema, hematoma, abscess formation, wound infection, cyst recurrence, and epididymal tubule obstruction, though the prognosis for most patients is favorable (7).

Epididymal cyst torsion, while rare, can lead to acute scrotal pain and redness. The diagnosis of torsion should be differentiated from other conditions, including testicular torsion, appendage torsion, spermatic cord torsion, epididymitis, orchitis, scrotal trauma, and testicular tumors (5). In cases of acute scrotal pain, the most critical differential diagnosis is testicular torsion, particularly within the first 6 h of symptom onset, as early intervention is key to preventing testicular injury (17). Ultrasound findings of epididymal cyst torsion often show a lack of blood flow, whereas conditions like epididymitis typically exhibit increased blood flow (4). Unfortunately, no clinical marker currently exists to definitively distinguish epididymal cyst torsion from other scrotal emergencies, and aggressive exploration may be the only reliable method of diagnosis. It has also been suggested that the presence of an epididymal cyst can alter the anatomical position and axis of the ipsilateral testis, thereby increasing the risk of testicular torsion in affected individuals (5). Among the 14 previously reported cases of epididymal cyst torsion (Table 1), none were associated with concomitant ipsilateral testicular torsion. Notably, our Case 3 represents a unique clinical scenario where both the cyst (720°) and testis (180°) underwent torsion—the first documented case of synchronous torsion involving an epididymal cyst and testis.

To validate the novelty of our case, we performed a systematic literature review up to May 31, 2025, across PubMed, Scopus, Embase, and Web of Science, using the search string: (“epididymal cyst” OR “spermatocele”) AND (“testicular torsion” OR “spermatic cord torsion”). After screening 58 unique publications following deduplication, none of the articles described the synchronous torsion of an epididymal cyst and ipsilateral testis (see PRISMA flow diagram, Figure 4). Therefore, to our knowledge, our Case 3 represents the first documented instance of this unique clinical scenario, where both the cyst (720°) and testis (180°) underwent synchronous torsion.

This finding provides partial validation of our earlier hypothesis while simultaneously suggesting that epididymal cysts may pose greater risks than previously recognized, particularly when large. Patients with long-standing sizable epididymal cysts may experience intermittent discomfort, potentially delaying medical attention. Therefore, patient education should emphasize: (1) recognizing new-onset scrotal pain or swelling, (2) understanding the risk of testicular torsion, and (3) seeking immediate evaluation to prevent diagnostic delays or errors.

Given these complexities, clinicians managing epididymal cysts must be vigilant for the possibility of torsion and promptly perform scrotal exploration to prevent or minimize testicular damage.

A limitation in the management of our case 3 was the absence of immediate microscopic analysis of the aspirated transparent white fluid for the presence of sperm cells. In the acute setting, where the primary clinical concern was the viability of the torsed testis, the surgical team's focus was directed toward rapid exploration and detorsion, and the differentiation between an epididymal cyst and a spermatocele was overlooked. The fluid sample was therefore sent for routine histopathological examination instead of semen analysis. Consequently, a definitive intraoperative differentiation between a simple epididymal cyst and a spermatocele based on fluid composition was not possible. This highlights a valuable learning point: in cases of synchronous pathology where testicular torsion is suspected, a systematic protocol for sampling and analyzing cystic fluid, even amidst surgical urgency, could provide crucial diagnostic information and enhance postoperative counseling.

Adolescent epididymal cysts are common benign lesions that are often mistaken for hydroceles. A spermatocele, which is a specific subtype of epididymal cyst, contains semen. Aspiration or elective excision are effective for non-acute cases. However, the cyst may undergo torsion and potentially induce testicular torsion, representing a previously underrecognized clinical risk. Given the unique characteristics of this developmental stage, it is crucial to provide personalized treatment strategies for adolescents with epididymal cysts.