Cancer incidence among Finnish patients with psoriasis treated with trioxsalen bath PUVA.

BACKGROUND: Systemic methoxsalen PUVA increases nonmelanoma skin cancer risk in a dose-dependent manner, whereas trioxsalen bath PUVA treatment has been suggested to be less carcinogenic. OBJECTIVE: Our purpose was to study the carcinogenicity of topical trioxsalen PUVA. METHODS: We performed a record linkage study of 337 male and 190 female patients with psoriasis treated with trioxsalen bath PUVA during the period 1977 to 1988 and the Finnish Cancer Registry (cancer incidence in the period 1977 to 1993). The mean follow-up period per person was approximately 11 years. Data on the total cumulative UVA dose and other potentially carcinogenic treatments were collected from the patients' files. The standardized incidence ratio (SIR) was calculated, in which the expected number of cases was based on the national cancer incidence rates. RESULTS: During the follow-up, 26 cancer cases were observed in the cohort versus 30 expected (SIR, 0.88; 95% confidence interval [CI], 0.57-1.28). The only primary sites showing high SIRs were cancer of the kidney (SIR, 3.56; 95% CI, 0.97-9.10) and non-Hodgkin's lymphoma (SIR, 2.94; 95% CI, 0.36-10.6). There was only one case of nonmelanoma skin cancer; the expected number was 0.8 (SIR, 1.26; 95% CI, 0.03-7.04). The average cumulative UVA dose was 65 J/cm2; 40 patients had received more than 200 J/cm2. The average number of treatments was 112; 65 patients had received more than 200 treatments. CONCLUSION: No excess of squamous cell carcinoma of the skin was found in patients treated with trioxsalen bath PUVA. However, because of the small size of the cohort, only a sevenfold excess risk can be excluded. The possible associations between psoriasis or its treatment and kidney cancer and lymphoma need to be studied further in larger series.

Irritant effects of a detergent in wash, chamber and repeated open application tests.

Development of irritant contact reactions in a wash test, in a repeated open application test (ROAT) and in chamber tests were compared with each other in 14 atopic and 14 non-atopic Caucasian medical students. In the wash test, the students washed their upper arm skin with 10% dishwashing liquid for 1 min 2 x a day for 1 week. In the ROAT, they applied the same detergent solution to 1 antecubital fossa 2 x daily for 1 week. Chamber tests were performed with the same detergent using 8 mm, 12 mm and 18 mm Finn Chambers applied to the upper back skin for 48 h. Additional 4 h and 24 h occlusion times were used with the 12 mm Finn Chambers. Test results were evaluated on days 0, 2, 4 and 7 by eye and by using an Evaporimeter EP1 for transepidermal water loss and a Minolta Chroma Meter CR-200 for skin colour. No statistically significant differences between atopics and non-atopics were found in any of the tests. The results of the tests did not correlate with each other, with the exception of the 12 mm/48 h chamber test and the wash test in atopics (R = 0.61, p = 0.02). It seems that other individual factors in addition to atopy influence the development of irritant contact dermatitis. The results of the chamber test and ROAT predicted poorly the result of the wash test.

Irritant effects of a detergent in wash and chamber tests.

Irritant properties of detergents can be tested by using patch and chamber tests and various kinds of use tests. The aim of the present study was to compare the results of use and 12 mm Finn Chamber tests. Study subjects (10 atopic and 11 non-atopic medical students) washed the outer aspect of 1 upper arm with liquid detergent for 1 minute 2 x daily for 1 week. 48-h chamber test with 5 concentrations of the same detergent in water were concurrently applied to upper back skin. Transepidermal water loss (TEWL), electrical capacitance and skin blood flow were measured to quantify reactions on days 0, 2, 5 and 7. Irritant contact dermatitis developed equally in atopics and non-atopics in the wash test, whereas in the chamber test with a 10% aq. solution of the detergent, increase in TEWL was significantly higher in atopics than in non-atopics. The chamber test results thus predicted poorly the result of the wash test. This might indicate that the wash test and the chamber test measure different aspects of skin barrier function.

Pacifiers and dental structure as risk factors for otitis media.

The purpose of the study was to examine the relationship between ear infections and dentition, sucking habits, pacifier sucking and atopic and allergic diseases in a historic cohort survey. The series comprised 944 5-year-old children representing about 3/4 of the whole age cohort. The parents completed a questionnaire that asked for details of the children's ear infections, sucking habits and atopic or allergic diseases diagnosed by a physician. The dental status was examined by the child's own local dentist. The children who had used a pacifier had a greater risk of having recurrent attacks of acute otitis media in their history than those who had not used a pacifier (risk ratio (RR), 1.43; 95% confidence interval (CI), 1.06-1.93; P = 0.02). Mouth breathing was significantly associated with acute otitis media (RR, 1.87; CI, 1.28-2.73; P = 0.01), as was open bite (RR, 1.36; CI, 1.01-1.84; P = 0.04), but no other mode of malocclusion. The population attributable risk of otitis media caused by pacifier amounted to a total of 478 attacks or 0.7 per child. The association between otitis media and the use of a pacifier remained even after adjusting for mouth breathing and the measures of malocclusion. Neither thumb sucking nor atopic eczema showed such an association.

Moisturizers prevent irritant dermatitis.

The purpose of this study was to investigate the ability of eight different moisturizers to prevent irritant dermatitis. Twelve healthy female students washed the outer aspect of their upper arms with a liquid detergent for one minute twice a day for one week. Seven skin creams and one skin oil were applied to 3 x 7 cm areas of the left upper arm just after each washing, while the right upper arm was left untreated. Transepidermal water loss (TEWL) (mean) increased from 7.1 to 9.3 g/m2/h (p less than 0.001) and laser-Doppler flowmetry (LDF) value (mean) decreased from 11.8 to 10.8 arbitrary units (N.S.) in the left upper arm, but there was no statistical difference between the eight moisturizers. During the second week of the study, the test subjects did not continue washing their arms. Eight areas (3 x 7 cm) of the right upper arm were treated with the moisturizers twice a day. The mean TEWL value decreased from 20.3 to 8.6 (p less than 0.0011) over 7 days, but there were no significant differences between the individual moisturizers. The laser-Doppler values showed the same trend as the TEWL values. In conclusion, regular use of emollients prevented irritant dermatitis from a detergent.

Predisposing factors for malocclusion in 7-year-old children with special reference to atopic diseases.

The relationships between malocclusion and atopic diseases (familial allergy) and other usual predisposing factors were studied clinically and biometrically in a nonselected cohort of 217 7-year-old children. Normal Class I occlusion was more common in children with atopic respiratory symptoms than in nonatopic children. Posterior crossbites were found in children with atopic dermatitis (P less than 0.05), those with frequent infections (P less than 0.05), and in those sucking their fingers or a dummy beyond the age of 4 years (P less than 0.05) more often than in other children. The present results provide further support for the view that atopic hyperreactivity is a predisposing factor for posterior crossbites.