Sun exposure and malignant melanoma among susceptible individuals

The purpose of this case-control study was to identify susceptible subgroups, primarily based on pigmentary characteristics, at higher risk of developing melanoma when exposed to the sun. The study group, which was interviewed from 1979 to 1982, consisted of 289 consecutive patients with melanoma and 527 randomly selected controls without cancer. In general, the risk of melanoma associated with sun exposure was greater for individuals expected to be susceptible on the basis of poor ability to tan, but not other pigmentary traits. There were, in addition, some noteworthy interactions between age and sun exposure. Among subjects with poor tanning ability, the risk of melanoma associated with outdoor occupation was more than 3-fold [odds ratio (OR) = 3.3] compared to indoor occupation. In contrast, the analogous OR was much less elevated among subjects with a good ability to tan (OR = 1.5). Mixed indoor and outdoor job exposure was protective among good tanners (OR = 0.80), but not among poor tanners (OR = 1.5). A similar pattern was seen for recreational sun exposure and, when applying multiple logistic regression, for the patient's overall subjective assessment of his lifetime sun exposure. However, quantitative assessment of average hours of sun exposure did not prove to be a good indicator of melanoma risk, even among susceptible individuals. A history of severe sunburn with blistering was associated with nearly 3-fold risk among poor tanners (OR = 2.9) but was protective among good tanners (OR = 0.79). A history of nonmelanoma skin cancer or solar keratosis was a very strong risk factor (OR = 7.3), which, however, did not significantly differ in magnitude among susceptibility subgroups.

Incidence and anatomic distribution of cutaneous melanoma among United States Hispanics

Using the data base for melanoma incidence compiled by the Surveillance, Epidemiology, and End Results (SEER) Program of the National Cancer Institute, we compared the incidence and anatomic distribution of primary cutaneous melanomas in Hispanic and non-Hispanic Caucasian populations and in blacks between 1973 and 1981. Cases were divided into United States whites, New Mexico (NM) whites (non-Hispanic Caucasians), NM Hispanics, Puerto Rico (PR) residents by definition Hispanic, and US blacks. Among whites, the highest incidence was 8.0 per 100,000 and was ten times that of US blacks. The incidence among PR and NM Hispanic residents was 1.6 to 3.7 times that of US blacks. The anatomic distribution among NM Hispanics was similar to US and NM whites for both genders. In contrast, among PR residents the anatomic distribution in both genders was most common for the leg, similar to that for blacks. Spaniards who migrated to PR have more admixture with blacks from Africa than Spaniards who migrated to the mainland. This suggests a genetic predilection for the occurrence of melanoma on the lower extremity among PR residents as opposed to NM Hispanics.

Resistant discoid lupus erythematosus of palms and soles: successful treatment with azathioprine

We present the case of two patients with an unusual form of discoid lupus erythematosus that was confined almost exclusively to the palms and soles. In both patients this form of discoid lupus erythematosus did not respond to conventional therapies, which included topical steroids, intralesional steroids, prednisone, quinacrine hydrochloride, hydroxychloroquine sulfate, colchicine, and dapsone. Both patients were then treated with azathioprine. One patient dramatically improved with azathioprine, worsened each time the azathioprine was stopped or reduced, and responded again to the reinstitution of therapy. The other patient began taking azathioprine 8 months ago and has also experienced relief of her symptoms. These cases suggest that discoid lupus erythematosus principally involving the palms and soles is difficult to treat with conventional medication and that azathioprine, which appears to be useful, should be tried after the failure of other therapies.

Skin cancer in blacks in the United States

Skin cancer is rare in blacks compared with whites in the United States. The most common form is squamous-cell carcinoma, not basal-cell carcinoma, as it is in whites. Sunlight does not appear to be an important etiologic factor in skin cancer in blacks, as most lesions occur on covered areas. Malignant melanoma is low in frequency but commonly affects acral areas and has a poor prognosis. Mycosis fungoides and dermatofibrosarcoma protuberans appear to have a high frequency among skin cancers. Squamous-cell carcinoma, malignant melanoma, and mycosis fungoides have a relatively high mortality rate in blacks. Bowen's disease and Kaposi's sarcoma occur in blacks but are rare. As there is a high frequency of squamous-cell carcinoma of the skin in blacks, prevention and early detection should benefit the patient. Considering the difficulties encountered in applying epidemiologic methods to skin cancer on a national scale, etiologic studies should be conducted in carefully selected areas. Future investigations of skin cancer in blacks should include an examination of risk factors such as burns, trauma, and diet and familial and immunologic aspects as well.

Incidence of non-melanocytic skin cancer treated in Australia

In 1985, as part of a national random household omnibus survey by a market research company, 30,976 Australians (mostly of European origin) were asked whether they had ever been treated by a doctor for skin cancer. The treating doctor or hospital was then approached for confirmation of the diagnosis of all those people who claimed to have been so treated within the past 12 months. Demographic data were also collected, permitting analysis by age, sex, country of birth, current residence, and skin reaction to strong sunlight. Melanomas accounted for less than 5% of the tumours treated. The world standardised incidence of melanoma was 19/100,000 population. The standardised incidence of treated non-melanocytic skin cancer in Australia was estimated to be 823/100,000. The standardised rates for basal cell carcinoma and squamous cell carcinoma were 657 and 166/100,000 respectively, yielding a standardised rate ratio of about 4:1. Standardised rates based on medically confirmed cases only were 555, 443, and 112/100,000 for all non-melanocytic skin cancers, basal cell carcinomas, and squamous cell carcinomas respectively. Significant differences and trends in incidence were noted with respect to age and sex. Rates in men were higher than those in women but significantly so only after the age of 60. People born in Australia had a rate of 936/100,000 compared with 402/100,000 in British migrants. Rates for non-melanocytic skin cancer showed a gradient with respect to latitude within Australia. The rate in people residing north of 29 degrees S was 1242/100,000 compared with a rate of 489/100,000 in those living south of 37 degrees S. A person's skin reaction to strong sunlight was a good indicator of the risk of skin cancer, tanning ability being inversely related to its incidence. The rate in those who always burnt and never tanned when exposed to strong sunlight was 1764/100,000 compared with a rate of 616/100,000 in those who always tanned and never burnt. These findings have important implications for public education programmes in relation to exposure to sunlight in Australia.

[Kaposi angiosarcoma in renal transplant recipients]

Four cases of Kaposi's sarcoma in recipients of renal transplants are reported. The 4 patients of Italian origin were male. Kaposi's sarcoma, began during pre-transplantation haemodialysis, then extended in one of the patients; in the remaining 3 patients it developed 20 months on average after transplantation. All patients were receiving an immunosuppressive treatment (azathioprine, systemic corticosteroids, anti-lymphocyte serum). Kaposi's sarcoma was located in the skin and mucosae, sometimes in lymph nodes and viscera. In 2 patients the cutaneous and mucosal lesions responded well to vindesine: in the other two patients withdrawal of the immunosuppressive therapy had no effect on the course of the disease. This study highlights the multiple factors involved in the development of Kaposi's sarcoma, notably immunosuppression and the ethnic factor.

Nonmelanoma skin cancer in Japanese residents of Kauai, Hawaii

A prospective 3-year survey of nonmelanoma skin cancer in Japanese-American residents of the Hawaiian island of Kauai was conducted beginning in January 1983. The crude rate for basal cell and squamous cell carcinoma was 123/100,000, 88 times higher than the corresponding figure from Japan. This discrepancy may be attributed to an increase in ultraviolet exposure due to lifestyle and latitude, but arsenic exposure may also have played a role. Nonmelanoma skin cancer in Japanese in Hawaii appears to be a significant problem that has not been appreciated because these malignancies are not reportable to tumor registries.