We present long-term follow-up data on patients with nodular localized primary cutaneous amyloidosis (NLPCA) seen at the St John's Institute of Dermatology between 1968 and 1999. This is the largest clinical follow-up study of this type of amyloid to date. Based on these cases we estimate the rate of progression of NLPCA to systemic amyloidosis to be only 7%, much lower than the 50% rate currently quoted in the literature.

Azathioprine and cyclosporin have been used as immunosuppressants for many years, but long-term use has also been associated with neoplasia. We report three cases of rapidly fatal Merkel cell carcinoma in patients who had been treated with azathioprine for many years either for rheumatoid arthritis or following organ transplantation. Two of these patients had also received cyclosporin. We suggest that Merkel cell carcinoma may be seen more commonly in immunosuppressed patients than in the normal population and that the oncogenic potential of azathioprine and cyclosporin should be borne in mind when prescribing these drugs.

Tanning lamps, emitting predominantly ultraviolet (UV) A, are used widely throughout the U.K. and other countries, but little is known about the long-term risks associated with their use, especially with respect to skin cancer. We have exposed normal human epidermal keratinocytes to a commercial tanning lamp and used the comet assay in association with DNA repair enzymes T4 endonuclease V and endonuclease III to investigate the relative yields of directly formed cyclobutane pyrimidine dimers (CPDs) and indirectly formed types of oxidative DNA damage. To put the risk of using tanning lamps into perspective, the sunbed used in this study (five Philips Performance 80W-R UVA tubes at a distance of 35 cm) was found to be approximately 0.7 times as potent at inducing CPDs as U.K. natural sunlight around noon on a fine summer day. This compares with a relative risk for CPD induction and erythema of 0.8 and 0.7 times, respectively, calculated from the relevant action spectra of tanning lamps and British noontime sunlight. To determine the relative contribution of UVB and UVA to the induction of CPDs and oxidative DNA damage, we modified the spectral output of the tanning lamps with a series of Schott WG UVB filters. The induction of CPDs was more dependent on the UVB component of the sunbed than oxidative types of damage. Schott WG UVB filters with 50% transmission at 305 nm reduced the yield of T4 endonuclease V sites by 42% while there was only a 17% decrease in the yield of endonuclease III sites. CPD induction was not completely abolished after irradiation through WG335 and WG345 nm filters despite there being no detectable UVB. From these data, it was estimated that, although the tanning lamps emitted only 0.8% of their total output in the UVB range, these wavelengths were responsible for the induction of over 75% of CPDs and 50% of the oxidative damage to DNA.

In 2000, a then 13-year-old girl was referred to our department with acne of 3 years duration. She had tried topical clindamycin, erythromycin, zinc acetate solution, benzoyl gel, and oral erythromycin with limited success.She was born with a dysmorphic facies, brachycephaly, exophthalmos with deficient supra-orbital ridges, and a depressed nasal septum. Coronal sutures were not palpable. Symmetrical syndactyly of the index-middle fingers and all toes was evident. A congenital disorder was diagnosed at birth. Subsequently she underwent several operations including cranioplasty at 4 months of age (CT head scan showed Dandy-Walker variant) and finger separation at 4 years. She had a physical and developmental delay of 1 year at 3 years of age, and early education in a special school.On examination she had obvious dysmorphic facial features (Fig. 1) and evidence of previous operations to her head and fingers (Fig. 2). Moderate pustular acne was seen on the forearms and back of the trunk (Fig. 3) but not on the face.Her acne was eventually cleared with isotretin gel, oral erythromycin, and then a 6-month course of oral isotrtinoin.