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An analysis of the relationship between the anatomic site of cutaneous melanoma, sun exposure, and phenotype was conducted in 355 women with histologically confirmed superficial-spreading melanoma and in 935 control subjects. The most frequent site for superficial-spreading melanoma was the leg. However, when major sun-related and phenotype risk factors were examined by site, risk ratios were lowest for melanomas that occurred on the leg. A history of frequent sunburns during elementary or high school, increased number of self-assessed large nevi, and blond hair were more strongly associated with melanoma sites other than the leg. Tumors on the trunk were more likely than tumors at other sites to be associated with histological evidence of a preexisting nevus. Results of this work indicate that associations between melanoma phenotypic factors may differ by anatomic site.

We studied 338 Caucasian women with superficial spreading melanoma (hereafter called melanoma) and 872 control subjects ages 25-59 years and compared characteristics of women who reported that they tanned with sun exposure with those who reported that they burned. The purpose of the study was to investigate how skin type, as measured by tendency to burn or tan, modified the effect of other melanoma risk factors. There was a clear relation between tendency to burn and prevalence of red hair, light complexion, freckles, and history of sunburns during elementary school and high school. Host factors such as light complexion and increased number of self-assessed large nevi elevated risk of melanoma among women of all skin types. Increased risk for melanoma associated with frequent sunburns during childhood and adolescence was most pronounced for women who burned and then tanned; risk was not substantially elevated for women who burned without tanning. Women who had a history of sunburns had an increased melanoma risk even if they reported tanning.

A population-based case-control study of cutaneous malignant melanoma (CMM) was conducted in 452 women with melanoma and 930 control subjects aged 25-59 years in five San Francisco Bay Area counties between 1981 and 1986. Women were interviewed in their homes with regard to history of sunlight exposure and sunburns during different periods in their lives, phenotypic and host characteristics, medical history, occupation, and demographic factors. Data were analyzed by the patients' histologic type of melanoma; 355 women were classified as having superficial spreading melanoma (SSM), 61 had nodular melanoma (NM), 13 had lentigo maligna melanoma, and 23 had other melanomas that could not be further classified upon histologic review by University of California dermatopathologists. Univariate results from analysis of factors related to sun exposure showed that the risk of all histologic types of CMM, SSM, and NM increased with increasing tendency of the subject to sunburn and with history of increased severity and/or frequency of sunburns up to age 12 years. Risk of all types of CMM and SSM also increased with increasing number of sunburns for all age groups and with lack of use of sunscreen. After adjustment for each other and for phenotypic factors, history of sunburn up to age 12 and lack of sunscreen use were the primary sun-related factors associated with an increased risk of all types of CMM and SSM, while tendency to sunburn when exposed to 1/2 hour of noontime sun and lack of use of sunscreen were related to NM. Although having frequent sunburns before age 12 and having severe sunburns before age 12 were both strongly associated with melanoma, having large numbers of sunburns during any time period from elementary school through age 30 years and having sunburns during the 10 years prior to diagnosis or interview were all associated with a doubling of risk for SSM after adjustment for other factors. These results suggest that the increased risk of melanoma related to sunburns is not confined to childhood sunburns. Maintenance of an all-year tan provided no protective effect against melanoma after adjustment for tendency to burn. No association was noted with use of fluorescent lights or exposure to sunlamps for all types of CMM, SSM, or NM.

A total of 452 women with cutaneous malignant melanoma and 930 control subjects aged 25-59 years participated in a population-based case-control study carried out in the San Francisco Bay Area between 1981 and 1986. Interviews were conducted in the homes of the women. Questions were asked about various phenotypic characteristics, including eye, hair, and complexion color, presence of freckles, and number of nevi, as well as medical history, history of exposure to sunlight, ability to tan, occupation, use of cigarettes and alcohol, and demographic factors. Histologic type of melanoma was considered in the analysis: 355 (79%) women were diagnosed with superficial spreading melanoma, 61 (13%) had nodular melanoma, 13 (3%) had lentigo maligna melanoma, and 23 (5%) had other melanomas that could not be further classified. For all cutaneous melanoma subjects combined, univariate results related to host factors showed that risk increased with the presence of nevi greater than 5 mm in diameter; light eyes, hair, and complexion; freckles; a history of skin cancer other than melanoma; a history of skin cancer in relatives; and maternal and paternal Northern or Central European ancestry. After adjustment for each other and for sun exposure factors, the phenotypic and host factors associated with all types of cutaneous malignant melanoma and superficial spreading melanoma were the presence of large nevi, light hair color, light complexion, and maternal Northern or Central European ancestry. Host factors associated with nodular melanoma after adjustment for other factors were the presence of large nevi, light hair color, ever being overweight by 20 pounds (9 kg) or more, and the presence of freckles.

Oral contraceptive use and reproductive factors were investigated in a population-based case-control study of 452 women aged 25-59 years who were diagnosed with cutaneous malignant melanoma during the period 1981-1986 and 930 controls. Ever use of oral contraceptives was reported by 72 percent of melanoma patients and 79 percent of control subjects in this San Francisco Bay Area study, although duration of use was slightly longer for women with superficial spreading melanoma (5.5 years) than for controls (4.3 years). While some subgroups had elevated or reduced odds ratios, no consistent association was observed between cutaneous melanoma risk and oral contraceptive use when use was examined by duration, latency, age at diagnosis, age at first use, and time period of first use. Neither number of live births nor age at birth of the first child was associated with risk for cutaneous melanoma; nor was a history of miscarriage, induced abortion, or endometriosis. No association was observed with regularity of menstrual periods or with use of fertility drugs or hormones to regulate menstrual periods. Women who reported experiencing hyperpigmentation of facial skin during a prior pregnancy had a lowered risk for all cutaneous melanoma (odds ratio (OR) = 0.64, 95% confidence interval (CI) 0.44-0.93) and superficial spreading melanoma (OR = 0.54, 95% CI 0.36-0.83). This effect was more pronounced for light-complexioned women (for superficial spreading melanoma, OR = 0.37, 95% CI 0.20-0.70) than for women with a dark or medium complexion (for superficial spreading melanoma, OR = 0.84, 95% CI 0.48-1.5). Women who reported use of acne medication also had a reduced risk of superficial spreading melanoma (OR = 0.55, 95% CI 0.35-0.84). These results indicate an overall lack of effect of oral contraceptives on cutaneous melanoma risk in this population of women. The reduced melanoma risks associated with hyperpigmentation during a prior pregnancy and use of acne medication (or related hormonal indications for its use) should be studied further.

Factors related to menopause and use of exogenous hormones other than p.o. contraceptives were examined in 452 women ages 25-59 who were diagnosed with cutaneous malignant melanoma. Control subjects for this population-based study in the San Francisco Bay Area were 930 women of the same age. An increased risk was observed for superficial spreading melanoma (SSM) in women who reached natural menopause after age 55 [odds ratio (OR), 3.6; 95% confidence interval (CI), 1.1-11.1], and for women who had had a bilateral oophorectomy within 9 years of their diagnosis with SSM (OR, 2.2; CI, 1.1-4.5). A somewhat elevated risk of melanoma after natural menopause or hysterectomy was no longer statistically significant after adjustment for exogenous hormone use. Prolonged use of p.o. exogenous hormones after hysterectomy for women who had retained at least one ovary was associated with an increased risk of SSM (OR, 5.4; CI, 1.5-19.3), and use of these products for fewer than 5 years after bilateral oophorectomy also was associated with an elevated risk of SSM (OR, 2.9; CI, 1.0-7.8). Conjugated estrogen use was associated with somewhat elevated risks for SSM after hysterectomy with one ovary retained (OR, 2.7; CI, 0.97-7.3) and after hysterectomy with bilateral oophorectomy (OR, 2.1; CI, 0.86-5.0). There was a suggestion of a trend for increased risk of SSM with increased dosage of conjugated estrogens after hysterectomy (P for trend = 0.07). Use of vaginal creams that contained estrogen also was associated with an increased risk of SSM (OR, 1.8; CI, 1.0-3.3).

A study of 121 melanoma patients and 139 control subjects was conducted among whites to examine and compare the distribution of non-dysplastic and dysplastic naevi and other pigmented lesions in each group. Melanoma patients had a mean of 97 melanocytic naevi which were greater than 2 mm in diameter and controls had a mean of 36 such naevi, while the medians were 58 and 22 respectively (p less than 0.0001). 55% of melanoma patients and 17% of controls had at least one clinically determined dysplastic naevus, and 26% of melanoma patients and 6% of controls had at least 5 dysplastic naevi. Men were found to have more naevi on the trunk than women in both melanoma cases (p = 0.01), and controls (p = 0.005). Dysplastic naevi were most often found on the trunk and were present at this location in 51% of cases and 17% of controls. Melanoma patients and control subjects with dysplastic naevi, when compared to those without these lesions, had larger number of non-dysplastic naevi. Lentigines were more common among melanoma patients that among control subjects (p = 0.02). There were no differences in the number of non-dysplastic naevi among cases with light and dark hair and eyes, or among controls with these characteristics. There also was little variation in the number of naevi according to number of blistering sunburns.