Why are HCG (Human Chorionic Gonadotropin), LDH (Lactate Dehydrogenase), and FSH (Follicle-Stimulating Hormone) levels checked in a patient with a testicular mass?

Tumor Markers in Testicular Mass Evaluation

HCG, LDH, and AFP are essential tumor markers in testicular mass evaluation as they aid in diagnosis, staging, prognosis determination, and treatment monitoring of testicular germ cell tumors. 1

Role of Each Tumor Marker

Human Chorionic Gonadotropin (HCG)

• Diagnostic value: Elevated in 64% of nonseminomatous germ cell tumors and approximately 30-40% of seminomas 2, 3
• Histological correlation: Always elevated in choriocarcinoma, but can be elevated in other histological types 2
• Specificity: Highly specific (100%) for testicular cancer when elevated 3
• Prognostic significance: Elevated HCG in seminoma patients may indicate higher risk of relapse 3

Lactate Dehydrogenase (LDH)

• Diagnostic value: Elevated in 62% of nonseminomatous tumors and up to 82% of advanced metastatic seminomas 2, 4
• Correlation with disease burden: Elevation increases with advancing stage and tumor bulk 4
• Prognostic significance: Part of the IGCCCG risk classification system; higher levels correlate with poorer prognosis 1, 5
• Monitoring utility: Reflects disease regression or progression during treatment 4

Alpha-Fetoprotein (AFP)

• Diagnostic value: Elevated in 67% of nonseminomatous tumors, but never in pure seminomas 2
• Histological correlation: Always elevated in tumors containing yolk sac elements 2
• Diagnostic exclusion: Elevated AFP in a patient with otherwise apparent seminoma indicates presence of nonseminomatous elements 1

Why FSH Is Checked

• Fertility assessment: FSH is part of baseline fertility evaluation in testicular cancer patients 1
• Reproductive counseling: Helps determine pre-treatment fertility status before potentially fertility-compromising interventions 1
• Hormonal function: Along with LH and testosterone, helps assess testicular endocrine function, especially important in patients with bilateral tumors or solitary testis 1

Clinical Algorithm for Testicular Mass Evaluation

1. Initial assessment:

   • Scrotal ultrasound with Doppler to confirm intratesticular mass 1
   • Draw tumor markers (HCG, LDH, AFP) before any surgical intervention 1
   • Assess baseline fertility with FSH, LH, testosterone levels 1

2. Diagnostic pathway:

   • Radical inguinal orchiectomy for definitive diagnosis 1
   • Repeat tumor markers 7 days post-orchiectomy to determine marker half-life kinetics 1

3. Staging workup:

   • Abdominopelvic CT scan for retroperitoneal lymph node assessment 1
   • Chest CT if abdominopelvic CT shows adenopathy or chest X-ray is abnormal 1
   • Tumor markers contribute to TNM staging and IGCCCG risk classification 1

Important Clinical Considerations

• Combined sensitivity: At least one of the three markers (HCG, LDH, AFP) is elevated in 91% of testicular germ cell tumors 2
• Marker persistence: Sustained or rising levels of HCG or AFP after orchiectomy indicate persistent or recurrent disease 2
• Surveillance utility: During follow-up, 70% of relapses are associated with an increase in one or both markers (HCG, LDH) 3
• False positives: LDH has lower specificity (93%) compared to HCG (100%) 3

Common Pitfalls

• Misinterpreting normal markers: Normal tumor markers do not exclude testicular cancer, especially in seminomas where marker elevation is less common 1
• Ignoring half-life: AFP half-life is 5-7 days and HCG half-life is 1-3 days; failure to normalize within expected timeframe suggests residual disease 1
• Overlooking fertility implications: Sperm banking should be discussed before orchiectomy or subsequent therapy 1
• Relying solely on markers for follow-up: Only 40-50% of relapses in clinical stage I disease are associated with marker increases; imaging remains essential 6

By understanding the role of these tumor markers, urologists can accurately diagnose, stage, and monitor patients with testicular masses, ultimately improving patient outcomes through appropriate treatment selection and follow-up.