That's the epididymis and it stores and transports sperm. You shouldn't feel any pain when doing the exam. Doctors say call your physician immediately if you feel a lump. The lump isn't necessarily cancerous. It may just be the result of an infection, but it's best to find out as soon as possible.
Early detection is the key to successful cancer treatment.
By the way, cancer rarely occurs in both testicles. Only one testicle is needed for full sexual function. Other Topics Health Watch is intended to provide general information only and should not replace the advice of a medical professional. You should contact your physician if you have questions about any of these topics.