UVB rays and skin cancer

By HSC Staff Writer • Published: March 30th, 2006
Category: Health in a Heartbeat

In both medical research and police work, sometimes wrongful accusations happen. Take the case of U-V-B, a type of ultraviolet radiation found in sunlight.

Scientists have long suspected that U-V-B exposure was a primary cause of malignant melanoma [MELL-uh-NO-muh], the most serious form of skin cancer.

But now it seems U-V-B may play a lesser role in the disease, according to a University of Texas study published recently in the Journal of the National Cancer Institute.

Ironically, the study provides new evidence U-V-B causes two milder skin cancers, basal [BAY-zull] cell carcinoma and squamous [SKWAY-muss] cell carcinoma.

Researchers took blood samples from about eight-hundred Caucasian men, some of whom were skin-cancer patients. They bombarded the samples with U-V-B, then looked for chromosome damage.

The results showed basal-cell and squamous-cell cancer patients had more chromosome damage than malignant melanoma patients and healthy men.

Skin cells weren’t used in the study. But the researchers believe their findings accurately represent the role U-V-B plays in all three types of skin cancer. That’s because all chromosomes in a person’s body should be equally vulnerable to radiation damage.

So if U-V-B isn’t the primary culprit behind malignant melanoma, what is?

One suspect is U-V-A, another type of ultraviolet radiation. Compared with U-V-B, it penetrates farther into the body, so it may affect the deeply placed cells where malignant melanomas begin.

Further investigation is needed, obviously. U-V-A might turn out to be the ringleader, but then, that’s what they said about U-V-B.