You can find a collection of medical photographs of enlarged testes and scrotums at the website SciencePhoto.com. Additional information on non-cancerous swellings is available at EmbarassingProblems.com.
Large testes are a symptom of several different medical conditions, including cancer. Doctors use visual identification and run tests to determine the exact cause, making photographs of large testes of interest to the medical community.
The gallery at Science Photo Library includes images of testes that have become swollen due to bruising and cellulitis, both of which have distinct visual cues. Swelling due to bruises presents with dark coloration, due to blood trapped under the skin, while swelling due to cellulitis presents with bright red surface skin.