Laboratory Monitoring for Testicular Cancer

Core Tumor Markers

The American College of Oncology recommends measuring alpha-fetoprotein (AFP), beta-human chorionic gonadotropin (β-HCG), and lactate dehydrogenase (LDH) before orchiectomy, after orchiectomy until normalization, during treatment, and throughout surveillance in patients with testicular cancer 1, 2
The half-life of AFP is 5-7 days, and it is produced by nonseminomatous germ cell tumors, specifically embryonal carcinoma and yolk sac tumor, with elevated AFP definitively excluding pure seminoma 3, 1, 2
The half-life of β-HCG is 1-3 days, and quantitative analysis of the beta subunit is required, with elevated β-HCG found in approximately 60% of patients with metastatic disease, although it can be mildly elevated in seminoma patients due to syncytiotrophoblastic giant cells 1, 2, 3
LDH is a less specific marker than AFP and β-HCG but is critical for prognostic stratification, with elevated LDH found in approximately 64% of patients with metastatic disease, and is essential for International Germ Cell Cancer Collaborative Group (IGCCCG) risk classification 3, 1, 2, 4

The National Comprehensive Cancer Network recommends obtaining AFP, β-HCG, and LDH before any surgical intervention to establish baseline values for diagnosis and subsequent monitoring, with normal marker levels not excluding testicular cancer due to low sensitivity, especially in seminoma 4, 1, 5
Repeat markers approximately 7 days after orchiectomy to assess half-life kinetics, and follow markers serially until normalization or until they reach a stable plateau, with persistent or rising markers after orchiectomy indicating metastatic disease 5, 4, 2, 1

The International Germ Cell Cancer Collaborative Group (IGCCCG) classification uses serum marker thresholds to stratify patients into good, intermediate, and poor prognosis groups, with LDH, β-HCG, and AFP levels used to determine the risk category 2
The IGCCCG classification is as follows: S1 (good prognosis): LDH <1.5× upper limit of normal (ULN), β-HCG <5,000 IU/L, AFP <1,000 ng/mL; S2 (intermediate prognosis): LDH 1.5-10× ULN, β-HCG 5,000-50,000 IU/L, AFP 1,000-10,000 ng/mL; S3 (poor prognosis): LDH >10× ULN, β-HCG >50,000 IU/L, or AFP >10,000 ng/mL 2

False elevations of β-HCG can occur due to hypogonadism from orchiectomy and chemotherapy, supplemental testosterone administration can reduce this false elevation, and heterophilic antibodies can cause false-positive hCG results 4
False elevations of AFP can occur due to hepatocellular carcinoma and other non-germ cell malignancies, and liver disease can elevate AFP independent of malignancy 4
LDH elevation alone without AFP or β-HCG elevation requires careful clinical correlation due to numerous non-malignant causes, and LDH has proven utility primarily for prognosis in chemotherapy-naïve patients with metastatic disease 4, 6