Testicular Cancer Types

According to the classic principles of human genetics, a fetus that is carrying Y-chromosome is genetically a male; however, the physical or physiological appearance of the fetus is determined by the complex interplay of different hormones and chemical mediators (such as hormones) that are released by gonads (like testicles).Testosterone, the primary male sex hormone (that is secreted and released by testes) is responsible for:

• Appearance of primary sexual characteristics (such as male genital organs at birth)
• Development of secondary sexual characteristics (such as puberty related changes like growth of Adam’s apple, enhancement in muscle mass, growth of genitalia etc.)
• Besides physical appearance, male testosterone is also responsible for normal sexual activities (such as normal libido, arousal, erection, sexual gratification etc.) and reproduction.

There are a number of other functions as well that requires optimally functional male reproductive glands like testicles.

What is Testicular Cancer and How is it Diagnosed?

Abnormal cellular division of testicular cells is referred to as testicular malignancy or cancer. It is usually diagnosed incidentally during a self-examination by the patient. In other cases, the primary care physician may detect the mass during a routine physical examination.The site, extent and location of testicular cancer is usually confirmed by a variety of investigational tools; such as:

• Ultrasound Scan: This test utilizes the sound waves to construct an image of the scrotal sac and the testes. A gel is applied on the scrotal sac and a hand-held ultrasound probe is used to transmit sound waves to assess the size, consistency and location of the lump.
• Blood Sample: Presence of certain chemicals (also known as tumor markers) also helps in assessing the histological variety and extent of tumor mass.
• Surgical Procedure to Excise a Testicle (Radical Inguinal Orchiectomy): After confirming the carcinogenicity of the testicular mass, surgical removal of that testis is advised. The resected specimen is then examined to further confirm the consistency of mass and type and grade of tumor.

Some Common Histological Varieties of Testicular Cancer

More than 90% testicular tumors originate from the testicular cells (also known as germ cell tumors). There are two primary histological varieties; such as:Seminomas:Classic Seminomas can occur at any age, but most cases are reported in adult middle aged males (age 30 to 45 years). The less frequently occurring Spermatocytic seminoma are usually reported in elderly males (mean age 65 years). These are slow growing tumors as compared to their counterparts and are less likely to metastasize. These tumors are marked by spiking serum levels of an abnormal protein, human chorionic gonadotropin (HCG) that is used for diagnosis as well as prognosis of this histological variety of testicular tumors.Nonseminoma: These are fast growing aggressive tumors that usually affect younger males. These tumors are further sub-classified as:

• Embryonal Carcinoma: This type of testicular cancer usually co-exists with other testicular cancers and have a tendency to metastasize outside of the testicular tissue. The tumor marker is alpha-fetoprotein(AFP) but in some cases, a rise in human chorionic gonadotropin (HCG) is also reported.
• Choriocarcinoma: This is perhaps the most aggressive variety with worst prognosis. The cancer cells have a high propensity to spread to distant organs like bones, spine, breast and bone.
• Yolk Sac Tumor: On histological examination, the cells mimic yolk sac of the embryo. The tumor is always associated with spiky serum levels of the tumor marker, alpha-fetoprotein(AFP).
• Teratoma: Most teratomas have multiple cellular varieties that mimics the embryonic layers of the developing embryo. Pure teratomas are relatively rare. The prognosis is generally poor.

Other less frequent type of testicular cancer is classified as Stromal tumors. The two primary histological varieties in this class are:

• Sertoli Cell Tumors originates from the surrounding supporting tissue of the testicles. Approximately 5% of all the testicular cancers are stromal cancers.
• Leydig Cell Tumors originates from the leydig cells of the testes (that are responsible for the secretion of sex androgens or testosterone). In advanced cases, these tumors also secretes estrogen.

Staging of the Testicular Cancer

After the confirmation of diagnosis, the estimation of exact stage of the cancer is very important. To find out if the cancer has spread beyond the confines of testes, these tests are done:

• Computerized Tomography (CT) scan. A sequential x-ray imaging of theabdomen or any other compartment of body is taken in CT scan to locate and identify the distant spread of the cancer.
• Blood tests. After removal of the testes, measurement of tumor markers in the blood helps to know if any leftover tumor still exists somewhere in the body.

The staging is done based on the conclusion of the above mentioned tests. Different stages are a helpful tool in deciding treatment plan. Testicular cancer is staged in the following manner:

• Stage I. Cancer is confined to the limits of testes only.
• Stage II. It has breached the confines of testes and reached an abdominal lymph node.
• Stage III. The cancer has spread to distant parts of the body. In the case of testicular cancer, most common spread is to the liver and lungs.

Fortunately, even in advanced cases (when the cancer has breached the confines of testes), the malignant process is very much treatable. There are several treatment options available depending on the stage and histological variety of cancer.

References:

1. http://www.cancer.org/cancer/testicularcancer/detailedguide/testicular-cancer-what-is-testicular-cancer
2. Movasaghi, Z., Rehman, S., & Rehman, I. U. (2012). Raman spectroscopy can detect and monitor cancer at cellular level: Analysis of resistant and sensitive subtypes of testicular cancer cell lines. Applied Spectroscopy Reviews, 47(7), 571-581.
3. Gilligan, T. D., Seidenfeld, J., Basch, E. M., Einhorn, L. H., Fancher, T., Smith, D. C., ... & Hayes, D. F. (2010). American Society of Clinical Oncology Clinical Practice Guideline on uses of serum tumor markers in adult males with germ cell tumors. Journal of Clinical Oncology, 28(20), 3388-3404.