Testicular Tumors

Testicular Tumors Overview & Classification - The Ball Game Basics

• Neoplasms of the testes; most common solid malignancy in men aged 15-35 years.
• Classification:
  • Germ Cell Tumors (GCTs): ~95%; derived from primordial germ cells.
    • Seminoma (most common GCT)
    • Non-Seminomatous GCTs (NSGCTs)
  • Sex Cord-Stromal Tumors (SCSTs): ~5%; arise from supportive tissues (Sertoli, Leydig cells).
    • Leydig cell tumors
    • Sertoli cell tumors
• Key Risk Factors:
  • Cryptorchidism (↑ 3-5x risk; most significant).
  • Family history; previous testicular GCT.
  • Klinefelter syndrome; testicular dysgenesis.

⭐ Cryptorchidism is the most significant predisposing factor for testicular germ cell tumors (especially seminoma).

Germ Cell Tumors: Seminoma - The Classic Contender

• Most common testicular germ cell tumor (GCT), peak incidence 30s.
• Gross: Homogenous, tan-yellow, lobulated cut surface; no hemorrhage/necrosis typically.
• Micro: Sheets of uniform cells with clear cytoplasm & prominent nucleoli ("fried egg" appearance), separated by fibrous septa with lymphocytic infiltrate.
• Markers: Positive for PLAP (placental alkaline phosphatase), OCT3/4, KIT (CD117). ↑hCG in ~15% (syncytiotrophoblastic cells).
• Excellent prognosis; highly radiosensitive & chemosensitive.

⭐ Seminomas are the male GCT equivalent of ovarian dysgerminomas.

• 📌 Mnemonic: Seminoma = Sensitive (to radiation), Simple (uniform cells), Syncytiotrophoblasts (sometimes present, produce hCG).

Germ Cell Tumors: Non-Seminomatous (NSGCTs) - The Diverse Villains

• Heterogeneous group with varied differentiation and aggressive potential. More aggressive than seminomas.
• Often occur as mixed germ cell tumors.

⭐ Yolk Sac Tumors are the most common testicular tumor in infants and children (<3 years), characterized by pathognomonic Schiller-Duval bodies and consistently elevated AFP.

Sex Cord-Stromal & Other Tumors - The Specialized Players

• Leydig Cell Tumors:
  • Androgen ↑ (precocious puberty in boys, gynecomastia in men).
  • Reinke crystals (eosinophilic, pathognomonic cytoplasmic inclusions).
  • Usually benign.
• Sertoli Cell Tumors:
  • Rare; may produce estrogens.
  • Form tubules/cords.
  • Usually benign.
• Testicular Lymphoma:
  • Most common testicular tumor in men >60 years.
  • Usually Diffuse Large B-cell Lymphoma (DLBCL).
  • Aggressive; often bilateral. Poor prognosis.

⭐ Testicular Lymphoma is the most common testicular tumor in men over 60 years, typically DLBCL.

Clinical Approach & Staging - The Diagnostic Drill

• Presentation: Typically painless testicular mass; may have dull ache/heaviness.
• Key Investigations:
  • Scrotal Ultrasound: Initial imaging to confirm solid mass.
  • Serum Tumor Markers (AFP, β-hCG, LDH): Baseline pre-orchiectomy. β-hCG ↑ in ~15% seminomas. Aid diagnosis, staging, prognosis, monitoring.
• Staging: AJCC TNM system; CT Chest/Abdomen/Pelvis for metastases.

⭐ Pure seminomas never produce AFP. If AFP is elevated, a non-seminomatous germ cell tumor (NSGCT) component is present.

High‑Yield Points - ⚡ Biggest Takeaways

• Germ cell tumors (GCTs) comprise 95% of cases; cryptorchidism is a key risk factor.
• Seminoma: most common GCT, radiosensitive, ↑PLAP, sometimes ↑hCG.
• Yolk Sac Tumor: most common in infants/children <3 yrs, ↑AFP, Schiller-Duval bodies.
• Choriocarcinoma: aggressive, early hematogenous spread, ↑↑hCG.
• Leydig Cell Tumor: may cause precocious puberty (androgens) or gynecomastia (estrogens).
• Teratoma: in adults malignant, in children benign; contains diverse tissues.
• Lymphoma: most common testicular malignancy in men >60 years an_bilateral_often_B-cell_type_