Ever vigilant: White patients with vitiligo should be monitored for signs of cancer

Key Points

Detroit - Older vitiligo patients with lighter skin types may have an increased risk of nonmelanoma skin cancer (NMSC) compared with the general population, according to a study conducted by dermatologists at the Henry Ford Health System (HFHS) here.

Study parameters

The study involved a retrospective review to identify persons seen at HFHS between January, 2001 and July, 2006, with a validated diagnosis of vitiligo, and those within that cohort having a biopsy-confirmed diagnosis of skin cancer.

Among 479 vitiligo patients seen at HFHS during the defined study period, only six had an NMSC. The six patients comprised five males and one female. There were four BCCs, all in males, and one female and one male each with an SCC.

All six patients were Caucasians with Fitzpatrick skin types I to III and 61 years of age and older. Two-thirds of the malignancies developed on normal, non-vitiliginous skin.

The comparison of the age-adjusted incidence rates of NMSC in the HFHS cohort against that of the Kaiser-Permanente cohort showed that with the exception of BCC in females, the rate of SCC in both gender groups and of BCC in males was higher in the vitiligo patients, although the differences were not statistically significant.

"These findings suggest vitiligo may be a risk factor for skin cancer in older, lighter-skinned individuals, although it seems skin pigment may not be the primary risk factor," says Iltefat Hamzavi, M.D., senior staff physician, department of dermatology, HFHS.

"To our knowledge, this is the largest study investigating the risk of skin cancer in persons with vitiligo. However, as is often the case, this research raised more questions than it answered, and our sample is still too small to be a basis for definitive conclusions.

"Nevertheless, we believe the findings support the suggestion that lighter-skinned individuals with vitiligo should be careful about sun exposure and should be monitored carefully for skin cancer," Dr. Hamzavi tells Dermatology Times.

The study was co-authored by Camile Hexsel, M.D.; Melody Eide, M.D., M.P.H.; Christine Johnson, Ph.D.; Richard Krajenta; G. Jacobsen; and Henry Lim, M.D.

Study objectives

Dr. Hamzavi says that one aim of the study was to investigate the question of what role skin pigment plays in cancer prevention, and vitiligo was identified as a good model for the research.

Among the 479 patients with vitiligo included in the study, race information was unavailable for 17 percent. The remaining population was split evenly between Caucasians and ethnic-racial groups with darker skin types (Fitzpatrick IV to VI).

Although there were no cases of skin cancer among the vitiligo patients with skin of color, Dr. Hamzavi says that, considering skin cancer is rare in the general population of darker-skinned persons, the study sample size was too small to establish the relative risk in persons with vitiligo.

"So far, the data suggest baseline skin type prior to the onset of vitiligo may have a bigger impact on skin cancer risk than skin pigment.

"However, from our study, we still cannot determine whether or not skin types IV to VI have an increased risk of skin cancer when they lose the color," Dr. Hamzavi says.

Another objective of the research was to examine UV phototherapy in vitiligo patients. None of the patients with skin cancer had received phototherapy.

Again, however, the researchers consider their database too small to provide information on which to base definitive conclusions.

"The data do not suggest UV phototherapy should be avoided in patients with vitiligo. However, considering the higher rates of skin cancer in the lighter-skinned group, it seems prudent these patients should be monitored carefully for skin cancer when treated with phototherapy," Dr. Hamzavi says.