When I was a fellow back in the 1980s, we had endless lectures and talks about every aspect of testicular cancer. In retrospect, this seems odd for a cancer which has less than 10,000 cases annually in the U.S. But testicular cancer has the distinction of being one of the great success stories of medical oncology. For while there has been a substantial degree of success in the treatment and cure of the “liquid” (hematologic) malignancies, one cannot say that the same degree of success has transitioned to the much more common solid tumors. But then there is testicular cancer. It is perhaps the only solid tumor in adults that is cured consistently in the metastatic setting with the use of chemotherapy.
I have always been impressed and sympathetic to how women are frightened of breast cancer seemingly out of proportion to other cancers. Actually, this has had implications for how cancer research funding is allocated. But when it comes to testicular cancer, men can barely mention it without squirming and cringing. This obviously does not reflect a fear of mortality from the disease inasmuch as testicular cancer is highly curable. Rather it reflects the enormous value that men place on those organs from the time of the schoolyard. Loss of a testicle to surgery does not usually affect a man’s fertility—one testicle is sufficient.
Testicular cancer is the most common cancer in males who are 15-35 years of age. There are few clear-cut risk factors except for an undescended testicle (a testicle that did not move down from the abdomen to the scrotum prior to birth) and a family history of testicular cancer.
About 90% of testicular cancers arise in the germ cells of the testis, the cells in the testis which produce the sperm. There are two major classes of these germ cell tumors (GCTs)—seminomas and non-seminomas. Seminomas grow slowly, are relatively indolent, and respond very well to radiation therapy and chemotherapy. Non-seminomatous GCTs (NSGCTs) are more aggressive and less responsive to these treatments, requiring more aggressive chemotherapy regimens. There are several subtypes of NSGCTs depending on which specific type of cell the tumor arises in. These include choriocarcinomas, teratomas, and yolk sac tumors. There are also less common testicular tumors that are not germ cell tumors, such as Leydig cell tumors—Leydig cells are the cells in the testicles which produce testosterone. And there can also be tumors which are of mixed cell type—always interesting to the clinician and to the tumor board (not necessarily to the patient).
How does one know if he has a testicular cancer? The most common symptom is a painless lump on a testicle. This would, of course, require evaluation by a urologist with histologic evaluation. About 75% of testicular lumps turn out to be cancer. Another common symptom is pain or swelling in the breast (one type of GCT produces HCG). As one might expect, the average man delays six months or more on average before consulting a physician about these symptoms.
At one time, the American Cancer Society recommended that men examine their testicles monthly in order to detect tumors early. However, there is no scientific data to support this recommendation. Thus, it is no longer recommended.
Some germ cell tumors produce tumor markers. These include alpha-fetoprotein (AFP), human chorionic gonadotropin (HCG), and/or lactic dehydrogenase (LDH). These markers can be of great assistance in establishing the diagnosis and in following the course of the illness.
As is true for other solid tumors, there is a staging system that involves four stages with progressively worse prognosis. The body is very protective of its germ cells in the testicle and ovary. Therefore, there is a blood-testicle barrier that prevents the passage of certain types of toxins into the testicles to reach the germ cells. It treats chemotherapy drugs as toxins and thus chemotherapy drugs do not penetrate well into the testicle. Therefore, an orchiectomy is absolutely required for every patient with a testicular cancer, no matter the stage.
Further management depends on the histology and stage. Seminomas are radiosensitive and therefore will usually be treated with radiotherapy, and perhaps chemotherapy if necessary. Non-seminomatous GCTs are relatively radioresistant and thus will be treated with chemotherapy. These chemotherapy regimens are relatively aggressive and complex, but are also highly effective. They are curative even for patients who are Stage 4 or recurrent.
The cure rate for testicular cancer varies somewhat by histology and stage but overall hovers around 95%. There is an increased risk of a second malignancy in the contralateral testicle in the future. And as noted above, fertility should be close to normal.
When I was a first-year fellow at Memorial over 40 years ago, I was assigned my first month in July to George Bosl, the cancer center’s specialist in testicular tumors. As a result, I probably saw more GCTs than the average medical oncologist sees in his career (only a handful since then—no pun intended). At the time we said, and I think it may still be true, that it was the medical oncologist’s favorite tumor because of the great success with it.
Alfred I. Neugut, MD, PhD, is a medical oncologist and cancer epidemiologist at Columbia University Irving Medical Center/New York Presbyterian and Mailman School of Public Health in New York. Email: [email protected].
This article is for educational purposes only and is not intended to be a substitute for professional medical advice, diagnosis, or treatment, and does not constitute medical or other professional advice. Always seek the advice of your qualified health provider with any questions you may have regarding a medical condition or treatment.
