A case-control study on 133 consecutive incident cases of nonmelanoma skin cancer registered by Cancer Registry of Ragusa (Sicily) was carried out in order to evaluate the correspondence between risk factors observed in other geographic areas with those of a Latin country with a strong solar exposure. A multivariate analysis showed that family history of skin cancer, cancer-related cutaneous diseases, fair skin color, residence more than 400 meters above sea level, and prolonged solar exposure without protection, significantly and independently increase the risk of skin cancer. Ease of suntanning was an important protective factor. Solar exposure was a stronger risk factor for squamous cell than for basal cell cancer. The results of the study enable us to identify a high risk group of people to whom simple methods of protection against solar exposure may be suggested to reduce the risk of skin cancer.

The clinical data of 2 population-based registries, located in areas with different incidence rates of colorectal cancer, were used in order to assess the role of familial factors in the pathogenesis of these tumors. The occurrence of tumors in family members was investigated in 389 subjects with colorectal cancer registered in Modena (Northern Italy, an area characterized by a high incidence of colorectal malignancies) between 1984 and 1986; similar information was obtained in 213 patients with tumors of the large bowel registered in Ragusa (Sicily, Southern Italy, an area of similar magnitude and with low incidence rates for these tumors) in the 3-year period 1988 to 1990. In both series, colorectal cancer occurred significantly more often among relatives of patients. Controls were patients of the same sex and age (+/- 5 years) hospitalized during the study periods, but not for gastrointestinal or neoplastic diseases. There were 89 cancer cases (3.1%) among 2,851 relatives of patients in Modena, vs. 17 cases among 1,744 relatives (1.0%) in Ragusa (p < 0.01). Apart from colorectal cancer, there was no excess of other types of tumors in patients' families (in both series). During the 3 years of registration, 17 cases of hereditary non-polyposis colorectal cancer (HNPCC, or Lynch syndrome) were diagnosed in Modena; in contrast, this syndrome was more rare in Ragusa (one case only during 3 years of observation). Similarly, many more families with clinical suspicion of HNPCC were recorded in Northern regions (44 vs. 10). Although incidence rates of colorectal cancer are appreciably higher in Northern than in Southern Italian regions, the excess of this cancer type among close relatives is similar. However, full-blown HNPCC or suspected Lynch syndrome were significantly more frequent in Northern Italy.

A case-control study has been carried out among women attending a screening service in Palermo (Sicily) from 1974 through 1983 to ascertain the distribution of the most frequently investigated risk factors for breast cancer in a southern European population. Information has been obtained from the archives of the screening service. The analysis was separately conducted for pre- and post-menopausal cases and non-cases. Risk factors for pre-menopausal women are: nulliparity (nulliparous versus parous: OR 2.17, 95% CI 1.41-3.32); age at first birth (25-29 versus less than 20: OR 2.16, 95% CI 1.17-4.00); interval between menarche and first birth (greater than 20 years versus less than 6: OR 5.34, 95% CI 2.08-13.66); number of births (greater than 4 versus 1-2: OR 1.98, 95% CI 1.10-3.50). Risk factors for post-menopausal women are: nulliparity (nulliparous versus parous: OR 2.18, 95% CI 1.59-2.99); age at first birth (greater than 29 versus less than 20: OR 1.84, 95% CI 1.13-2.99); interval between menarche and first birth (16-20 years versus less than 6: OR 2.15, 95% CI 1.20-3.85). Age at menarche, age at menopause, breast feeding and family history were not found to be risk factors for breast cancer in the investigated population. The existence of influencing differences between northern and southern populations has been postulated.

A case-control study on breast, cervix and endometrium cancer cases registered in Ragusa between January 1, 1983 and June 30, 1985 has been conducted. Information on risk factors has been obtained by means of a structured questionnaire. Risk factors for endometrium cancer were: few children (1-2 vs greater than 4 OR 15.18, 95%CL 1.96-117.64), oestrogenic treatment (OR 2.20, 95%CL 1.05-4.90), obesity (Quetelet index greater than 30 vs less than 22 OR 10.42, 95%CL 1.30-83.86), family history (OR 2.87, 95% CL 1.05-7.83). Risk factors for cervix uteri cancer were: multiple abortions (greater than 2 vs 0 OR 9.87, 95%CL 1.46-66.66), no contraception (OR 8.33, 95%CL 2.38-25.00), younger age of mother at birth (OR 6.89, 95%CL 1.71-27.70). Age at menarche, age at menopause and years of fertile life were not found to be related to either endometrium or cervix uteri cancer. The existence of influencing differences (ancestry, environment, lifestyle) has been postulated.

Incidence rates of lip cancer in males in Ragusa (Sicily) are amongst the highest in Europe [age-standardized rate (world) for 1980-82: 7.5 per 100,000]. A case-control study was conducted on 53 male cases and 106 controls matched for sex, age (+/- 2 1/2 years), residence and hospital from which cases had been drawn. Individual interviews were carried out for the evaluation of ethnic, environmental, pathologic and occupational risk factors. Lip cancer was significantly associated with: fair, brown, or red hair (relative odds = 2.3), blue eyes (r.o. = 5.3), fair skin (r.o. = 8.0), sensitivity to sunburns (r.o. = 4.1), working outdoors (r.o. = 4.9), coexistence of non-specific lesions of exposed body parts (r.o. = 12,2), low socioeconomic status (r.o. = 15.8), farming (r.o. = 2.6) and working in greenhouses (r.o. = 12.0). Recall of recurrent Herpes labialis was not significantly associated; also association with tobacco smoking was not significant after adjustment for socioeconomic status. Risk increased exponentially with the number of ethnic characteristics of northern European populations.