Testicular Tumors

Introduction

• Testicular tumors can be of germ cell or non-germ cell origin
  • germ cell origin
    • are the majority (95%) and are more commonly malignant
  • non-germ cell origin
    • usually benign
• Epidemiology
  • incidence
    • most common cancer in men between 15-35 years
  • risk factors
    • cryptorchidism
    • Klinefelter syndrome
• testicular feminization

Classification

• Germ cell types 
  • seminoma
    • malignant
    • most common testicular tumor
    • mostly affecting males 15-35 years
    • commonly metastasizes to para-aortic lymph nodes before hematogenous spread
  • embryonal carcinoma
    • malignant
    • commonly metastasizes early
  • yolk sac (endodermal sinus) tumor
    • seen in children < 4 years
  • choriocarcinoma
    • malignant
  • teratoma
    • mature teratoma in males is most often malignant
      • unlike females
• Non-germ cell types
  • Leydig cell (sex-cord stromal)
  • Sertoli cell (sex-cord stromal)
  • Testicular lymphoma
    • most common testicular cancer in older men
• involves both testes

Presentation

• Symptoms
  • painless unilateral enlargement of testes
  • seminoma
    • homogenous testicular enlargement
  • embryonal carcinoma
    • painful
  • choriocarcinoma
    • gynecomastia
      • due to hCG production which is an LH analogue
  • Leydig cell
    • usually androgen producing
      • gynecomastia in men
      • precocious puberty in boys
• Physical exam
• solid mass of the testes is always cancer

Evaluation

• Histology
  • seminoma
    • large cells in lobules with watery cytoplasm  
    • “fried egg” 
      • analogous to dysgerminoma of the ovary
  • embryonal carcinoma
    • glandular/papillary
  • yolk sac (endodermal sinus) tumor
    • yellow, mucinous
    • Schiller-Duval bodies resemble primitive glomeruli
  • choriocarcinoma
    • disordered syncytiotrophoblastic and cytotrophoblastic elements
  • teratoma
    • contain three tissue types
  • leydig cell
    • contains Reinke crystals
    • golden brown color
• Serology
  • LDH
    • non-specific
  • specific tumor markers
    • embryonal carcinoma
      • ↑ AFP and hCG
    • yolk sac (endodermal sinus) tumor
      • ↑ AFP
    • choriocarcinoma
• ↑ hCG

Treatment

• Pharmacologic & radiation
  • radiation therapy
    • indications
      • seminoma is radiosensitive
• Surgical
• orchiectomy 

Prognosis

• Seminoma
  • late metastasis and excellent prognosis
• Embryonal
  • worse prognosis than seminoma
• Choriocarcinoma
  • worst prognosis
    • in contrast to good prognosis in females
    • metastasizes to lungs