Early detection of melanoma: an educational campaign in Padova, Italy

To evaluate a public campaign for the early referral and treatment of cutaneous melanoma, an educational programme based on self-selection by subjects was organized in Padova, Italy in 1991. In the period from 1991 to 1996, 90,000 leaflets containing information on naevi, melanoma and skin self-examination were mailed to each household, reaching a population of 243,000 subjects. A total of 2050 individuals requested a skin check as a result of the leaflet. Most were at low risk, the majority being female (68%) and aged under 40 years (51.6%), with no risk factors (58.3%). One hundred and ninety subjects were referred for surgery for pigmented and non-pigmented suspect lesions. Histological diagnoses, obtained for all lesions, comprised 13 melanomas, 17 dysplastic naevi, 17 basocellular carcinomas, 140 pigmented benign lesions and three lesions of other types. The percentage of thin melanomas (< 1.50 mm) was 92.3%. Three hundred and fifty patients considered at risk at the first skin examination attended regular follow-up examinations. The sensitivity and predictive positive value of the visual examination were 92.8% and 6.8%, respectively. The impact of this campaign was evaluated in the Local Health District of Padova, comparing data from the pre-campaign period (1987-1990) with those from the campaign period (1991-1996); a trend towards a lower stage was observed (mean thickness 2.0 mm versus 1.50 mm; P < 0.02).

Influence of metabolic genotype GSTM1 on levels of urinary mutagens in patients treated topically with coal tar

Fifteen hospitalized, non-smoking, dermatological patients were treated with ointment containing 2% coal tar (CT) in order to assess the influence of metabolic genotype GSTM1 on urinary mutagen levels. Urinary 1-pyrenol, the main metabolite of pyrene, was used to check the high exposure to PAH of this population. The mean levels of urinary 1-pyrenol found in the 24-h urine of our patients were 467. 8+/-211.0 nmoles-24 h (range 94.6-890.1 nmoles-24 h). Mutagenicity was assessed on urine samples collected over a period of 24 h, after three consecutive days of topical application, using the bacterial mutagenesis test on Salmonella typhimurium strains TA98 and YG1024 in the presence of microsomal enzymes. The latter strain turned out to be more sensitive than the former in revealing urinary mutagens in these patients (42 693+/-30 867 vs. 6877+/-6040 net revertants-24 h). The mutagenicity on YG1024 strain and 1-pyrenol levels of urine samples were correlated (Spearman's rank correlation coefficient=0. 6678, P<0.01, z=2.795). The influence of genotype GSTM1 on urinary mutagen levels was assessed on strain YG1024. The values of urinary mutagenicity of subjects with genotype GSTM1-null (n=6) were on average higher than those of GSTM1-positive subjects (n=9) (55 498+/-45 957 vs. 34 156+/-11 933 net rev.-24 h), a non-significant statistical difference. The mean total excretion of mutagens corrected for PAH exposure (net rev./nmoles of urinary 1-pyrenol) in GSTM1-null patients was double that of GSTM1-positive ones (136. 8+/-34.7 vs. 70.8+/-23.3 net rev./nmoles of urinary 1-pyrenol; one-tailed Mann-Whitney U-test, U=11.5, P<0.05). These results indicate a greater body burden of promutagens, resulting from skin application of CT, in GSTM1-null subjects.

[Nickel-induced allergic contact dermatitis: reactivation by oral administration of hapten]

Recent reports suggest the high frequency of nickel induced allergic contact dermatitis and the absence in some patients of a clinical improvement following topical avoidance of sensitising allergen. In this study we evaluated the role of food ingested nickel in the maintenance and exacerbations of the disease. A high frequency of cutaneous exacerbations was obtained after oral challenge with a low nickel containing diet. These results suggest a pathogenetic role of nickel present in foods and indicate that an appropriate diet may be useful in the prophylaxis and in the therapy of nickel dermatitis in sensitized patients.

Chromosomal alterations in peripheral blood lymphocytes, urinary mutagenicity and excretion of polycyclic aromatic hydrocarbons in six psoriatic patients undergoing coal tar therapy

Six male non-smoking subjects treated for psoriasis with topical applications of pure coal tar or 4% coal tar-containing ointment were examined in order to assess the genotoxic risk associated with this type of therapy. Mutagenicity in urine samples collected before and during the coal tar therapy was evaluated in the plate incorporation assay on Salmonella typhimurium strain TA98 in the presence of S9 mix and beta-glucuronidase. Total urinary polycyclic aromatic hydrocarbon (PAH) levels were evaluated in parallel by high resolution gas chromatography/mass spectrometry. In addition, sister chromatid exchanges and chromosomal aberrations were also analysed in peripheral blood lymphocytes collected before, during and after the end of the coal tar applications. The results suggest that urinary mutagenicity levels as well as the frequencies of chromosome aberrations and sister chromatid exchanges in lymphocytes are related to the levels of exposure to coal tar. Moreover the kinetics of repair of chromosome damage in relation to different exposure levels and the capacity of the urinary mutagenicity assay to correctly identify the exposure to significant levels of PAH are discussed.