Almost all testicular cancers start in the germ cells.
The two main types of testicular germ cell tumours are seminomas and non-seminomas.
These 2 types grow and spread differently and are treated differently.
Non-seminomas tend to grow and spread more quickly than seminomas.
Seminomas are more sensitive to radiation. A testicular tumour that contains both seminoma and non-seminoma cells is treated as a non-seminoma.
Seminomas
Seminomas tend to grow and spread more slowly than non-seminomas. The 2 main subtypes of these tumors are classical (or typical) seminomas and spermatocytic seminomas. Doctors can tell them apart by how they look under the microscope.
Classical seminoma: More than 95% of seminomas are classical. These usually occur in men between 25 and 45.
Spermatocytic seminoma: This rare type of seminoma tends to occur in older men. The average age of men diagnosed with spermatocytic seminoma is about 65. Spermatocytic tumors tend to grow more slowly and are less likely to spread to other parts of the body than classical seminomas.
Some seminomas can increase blood levels of a protein called human chorionic gonadotropin(HCG). HCG can be detected by a simple blood test and is considered a tumor marker for certain types of testicular cancer. It can be used for diagnosis and to check how the patient is responding to treatment.
Non-seminomas
These types of germ cell tumors usually occur in men between their late teens and early 30s. The 4 main types of non-seminoma tumors are:
- Embryonal carcinoma
- Yolk sac carcinoma
- Choriocarcinoma
- Teratoma
Most tumors are a mix of different types (sometimes with a seminoma component as well), but this doesn’t change the general approach to treatment of most non-seminoma cancers.
More information can be found here http://www.urologicalcancercentre.com.au/testicular-cancer/