While women tend to seek medical treatment quickly after detecting a lump in their breast, men aren't quite as diligent. Typically, they wait two or three months after discovering a suspicious lump or swelling in their testicle.

"I think part of it is the macho man complex — that everything is fine," said Dr. Jay Raman, chief of urology at Penn State Milton S. Hershey Medical Center. "Then you add on top of that the fact that it is a sensitive area, and they may have some embarrassment about it."

In addition, men may fear they have cancer, but believe the only treatment is surgical removal of the testicle. "So they wait to see if it gets better on its own," Raman said. "But sometimes they wait and wait until they’ve waited too long."

If testicular cancer is diagnosed early, before spreading and when it's still confined to the testicle, the cancer is highly treatable: The survival rate is 99 percent five years after diagnosis.

Although the cancer is relatively rare with only about 9,000 new cases a year in the United States, it develops by mutation of the germ cells, which are most active during prime reproductive years of 20 to 35. Men in that demographic are the least likely to seek medical attention for any reason.

Since the risk factors — being Caucasian and having a history of a testicle that didn't descend when younger — are not preventable, Raman says the best defense is to be aware of the risks and symptoms, and to do regular testicular self-exams at least every six months.

"What you are feeling for is that both testicles have the same contours — relatively smooth and soft, kind of the consistency of a hard-boiled egg or the palm of your hand," Raman said. "If you notice anything firm, or lumps or bumps — something that is different on one side than the other —  you should seek medical attention right away."

Symptoms of testicular cancer include a lump in either testicle and a feeling of heaviness in the scrotum, says the Mayo Clinic. Other tip-offs include swelling of the scrotum, swollen lymph nodes, weight loss, and pain in the lower back.

Testicular cancer is diagnosed through an office exam and ultrasound. If a mass is detected, a CT scan and blood work show whether the cancer is confined or has spread. An orchiectomy — removal of the testicle — is the most common treatment.

If the cancer is confined to the testicle, patients usually need only follow-up exams and blood work. Once it has spread, chemotherapy and radiation treatment may be necessary.

"Probably one of the reasons the cure rate has gotten better in the past 20 to 30 years is that the chemotherapy drug regimens we have to treat it have improved significantly," Raman said.

Men with only one testicle can usually have children without any problems. For those whose cancer has spread and need chemotherapy or radiation treatment, Raman often recommends banking sperm since those treatments can kill remaining germ cells and affect fertility.

"The most important thing to know is that cure rates are directly tied to how early you find it," Raman said.