Pathologists have investigated the exact histology of testicular cancer and described 5 types of germinal cancers and 7 types of non-germinal cancers among all of the testicular cancers. But if we simplify a bit, we can narrow the majority of testicular cancers into 6 categories as is shown here:
Histological types of testicular cancer and frequency
seminoma : 40% of all cases
embryonal carcinoma : 25%
teratocarcinoma : 25%
teratoma : 5%
choriocarcinoma : 1%
others, more rare types : 4%
It is evident that 90 % of all testicular cancers are actually a seminoma, embryonal carcinoma or teratocarcinoma. Why is this important, why even care? Because each of these cancers has a different quality and tends to behave differently with respect to responding to various therapeutic modalities. For instance, embryonal carcinoma is an immature, rapidly dividing cell type.
It has a tendency to metastasize earlier, but is sensitive to chemotherapy or radiotherapy. Seminoma is the most common testicular cancer in the age group of 30 to 40, where about 85% of men who get testicular cancer have this type. It is a well differentiated tumor cell and in about 15% of cases there are other trophoblastic cell elements present, which produce the beta-subunit HCG (beta hcg). This then allows in 15% of cases to monitor for the progress of the disease as it is being treated by watching the HCG levels.
References
1. Cancer: Principles &Practice of Oncology.4th edition. Edited by Vincent T. DeVita, Jr. et al. Lippincott, Philadelphia,PA, 1993. Chapter on Cancer of the Testis.
2. Cancer: Principles&Practice of Oncology. 5th edition, volume 1. Edited by Vincent T. DeVita, Jr. et al. Lippincott-Raven Publ., Philadelphia,PA, 1997. Chapter on Cancer of the Testis.
3. Votrin II et al. Drugs Exp Clin Res 2000;26(5-6):267-273.
4. B Aschhoff Drugs Exp Clin Res 2000;26(5-6):249-252.
5. Conn’s Current Therapy 2004, 56th ed., Copyright © 2004 Elsevier
6. Ferri: Ferri’s Clinical Advisor: Instant Diagnosis and Treatment, 2004 ed., Copyright © 2004 Mosby, Inc