Testicular Bumps During Puberty: Epididymal Cysts and When to Worry

**Small, firm, painless scrotal bumps during puberty are usually benign epididymal cysts** — not cancer.

What They Are

• Fluid-filled cysts arising from epididymal tubules
• Stimulated by testosterone-driven epididymal growth
• Typically 2–10 mm, mobile, non-tender, transilluminate
• Often multiple, bilateral

Normal vs. Concerning Features

Reassuring (Benign)	Concerning (Needs Evaluation)
Painless, stable size	Rapid growth
Mobile, separate from testis	Fixed to testicle
Transilluminates (light passes)	Solid on transillumination
No systemic symptoms	Pain, heaviness, ache
Age-appropriate puberty	Prepubertal or adult new onset

Other Possibilities

• Spermatoceles (cyst of epididymal head, similar)
• Hydrocele (fluid around testis, transilluminates)
• Varicocele (dilated veins, "bag of worms" feel)
• Testicular cancer (hard, fixed, non-tender mass **within** testis) — **most common cancer 15–35y**

Guidance

1. Monthly testicular self-exam (after warm shower).
2. Any new lump → pediatrician/urologist within 1–2 weeks.
3. Ultrasound = definitive imaging (painless, no radiation).
4. Most cysts: observe. Large/symptomatic → aspiration or excision.

Puberty brings many lumps. Most are harmless. But **never assume** — get it checked.