Testicular cancer is cancer that develops in the testicles, a part of the male reproductive system. Symptoms may include a lump in the testicle or swelling or pain in the scrotum. Treatment may result in infertility.
Risk factors include an undescended testis, family history of the disease, and previous history of testicular cancer. More than 95% are germ cell tumors which are divided into seminomas and non-seminomas. Other types include sex-cord stromal tumors and lymphomas. Diagnosis is typically based on a physical exam, ultrasound, and blood tests. Surgical removal of the testicle with examination under a microscope is then done to determine the type.
Testicular cancer is highly treatable and usually curable. Treatment options may include surgery, radiation therapy, chemotherapy, or stem cell transplantation. Even in cases in which cancer has spread widely, chemotherapy offers a cure rate greater than 80%.
Globally testicular cancer affected about 686,000 people in 2015. That year it resulted in 9,400 deaths up from 7,000 deaths in 1990. Rates are lower in the developing than the developed world. Onset most commonly occurs in males 20 to 34 years old, rarely before 15 years old. The five-year survival rate in the United States is about 95%. Outcomes are better when the disease remains localized.
Signs and symptoms
One of the first signs of testicular cancer is often a lump or swelling in the testes. The U.S. Preventive Services Task Force (USPSTF) recommends against routine screening for testicular cancer in asymptomatic adolescent and adults including routine testicular self-exams. However, the American Cancer Society suggests that some men should examine their testicles monthly, especially if they have a family history of cancer, and the American Urological Association recommends monthly testicular self-examinations for all young men.
Symptoms may also include one or more of the following: a lump in one testis which may or may not be painful sharp pain or a dull ache in the lower abdomen or scrotum a feeling often described as "heaviness" in the scrotum firmness of the testicle breast enlargement (gynecomastia) from hormonal effects of β-hCG low back pain (lumbago) due to the cancer spreading to the lymph nodes along the back
It is not very common for testicular cancer to spread to other organs, apart from the lungs. If it has, however, the following symptoms may be present: shortness of breath (dyspnea), cough or coughing up blood (hemoptysis) from metastatic spread to the lungs a lump in the neck due to metastases to the lymph nodes
Testicular cancer, cryptorchidism, hypospadias, and poor semen quality make up the syndrome known as testicular dysgenesis syndrome.
Causes
A major risk factor for the development of testis cancer is cryptorchidism (undescended testicles). It is generally believed that the presence of a tumor contributes to cryptorchidism; when cryptorchidism occurs in conjunction with a tumor then the tumor tends to be large. Other risk factors include inguinal hernias, Klinefelter syndrome, and mumps orchitis. Physical activity is associated with decreased risk and sedentary lifestyle is associated with increased risk. Early onset of male characteristics is associated with increased risk. These may reflect endogenous or environmental hormones.
Higher rates of testicular cancer in Western nations have been linked to the use of cannabis.
Mechanisms
Most testicular germ cell tumors have too many chromosomes, and most often they are triploid to tetraploid. An isochromosome 12p (the short arm of chromosome 12 on both sides of the same centromere) is present in about 80% of the testicular cancers, and also the other cancers usually have extra material from this chromosome arm through other mechanisms of genomic amplification.
Diagnosis
The main way testicular cancer is diagnosed is via a lump or mass inside a testis. More generally, if a young adult or adolescent has a single enlarged testicle, which may or may not be painful, this should give doctors reason to suspect testicular cancer.
Other conditions may also have symptoms similar to testicular cancer: