HCG is tumour marker for:
|B||Chorio carcinoma and seminoma|
|C||Chorio carcinoma and non seminomatous tumours|
|D||Chorio carcinoma, hepatoma and malignant teratoma of testes|
a. Measurement of serum AFP can help identify tumors amenable to a testis-sparing procedure.
b. AFP is an amino acid with a single polypeptide chain that is produced by the fetal yolk sac, liver, and gastrointestinal tract. YSTs invariably produce AFP, and all AFP-positive tumors are considered to contain yolk sac elements .
c. Teratomas and other benign lesions are associated with normal AFP levels.
d. AFP has a half-life of approximately 5 days.
e. It is important to note that AFP levels may be elevated in infant boys and do not always represent the presence of a malignant tumor or persistent disease after orchiectomy for YST.
f. Normal adult reference laboratory values for AFP cannot be used in young children because AFP synthesis continues after birth .
g. Normal adult levels (<10 mg/mL) are not reached until 8 months of age .
h. Human chorionic gonadotropin, β subunit (β-HCG), is a glycoprotein produced by embryonal carcinoma and mixed teratomas.
i. The normal value of β-HCG is less than 5 IU/L.
j. The half-life of β-HCG is approximately 24 hours.
k. β-HCG is rarely elevated in preadolescent tumors.
l. The other germ cell tumors, in order of frequency, are immature teratoma; endodermal sinus, or "yolk sac," tumor; mixed tumors; embryonal carcinomas; and choriocarcinomas.
m. Elevated AFP levels are found in all patients with endodermal sinus tumors and mixed tumors that contain this component.
n. Embryonal carcinomas are associated with abnormal levels of both AFP and hCG, and choriocarcinomas secrete Hcg.