A. Extratesticular Mass

1. Epididymitis - pain
2. Spermatocele
3. Varicocele (Venous Occlusion, L>>R)
4. Hydrocele
5. Hernia (Scrotal)
6. Elephantiasis (Filariasis)
7. Epididymal Cyst
8. Abscess

B. Intratesticular Mass

1. Neoplasm [1]
   1. Germ cell tumors: seminoma, teratoma, choriocarcinoma, yolk-sac tumor, embryonal
   2. Leydig or Serterli Cell Tumor
   3. Rare: mesothelioma, sarcoma, adenocarcinoma of collecting system
   4. Primary Testicular lymphoma: rare
   5. Metastases to testes are rare
2. Orchitis (Mumps)
3. Abscess
4. Hematoma

C. Testicular (Scrotal) Pain

1. Torsion
2. Hernia
3. Epididymitis and Orchitis (most common)
4. Symptomatic Hydrocele

References

1. Ballen KK and Hasserjian RP. 2004. NEJM. 350(20):2081 (Case Record)