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Ultraviolet light (UV) B-induced inflammation is characterized by dramatic increases in prostaglandin E2 (PGE2) synthesis due to enhanced arachidonate deacylation from the membrane. Therefore, the effect of UV on sythesis, mass, and distribution of the high-molecular-weight phospholipase A2 (cPLA2) in cultured human keratinocytes and human skin was studied. The 105-kDa cPLA2 was demonstrated to be the critical enzyme in UV-induced PGE2 synthesis and erythema in the first 6 h postirradiation. Immunoprecipitation of 35S-labeled protein showed cPLA2 synthesis increased three- to fourfold 6 h after irradiation. Immunoprecipitated 32P-labeled cPLA2 demonstrated phosphorylation of cPLA2 was concurrently induced, suggesting that UV also activates cPLA2. This increase in cPLA2 synthesis and activation also closely correlated with increased PGE2 synthesis and [3H]arachidonic acid release and was effectively blocked by both an S-oligonucleotide antisense to cPLA2 and methyl arachidonate fluorophosphate, a specific inhibitor of cPLA2. Biopsy and histochemical examination of erythematous sites expressed increased amounts of cPLA2 whereas nonerythematous irradiated sites did not. In contrast, cyclooxygenase-1 and -2 in cultures and skin explants were unaffected 6 h post-UV, and no change in cyclooxygenase activity was observed at this time. These results suggest that increased cPLA2 synthesis occurs only when skin is exposed to UV doses that are sufficient to cause erythema and indicate expression of cPLA2 participates in acute UV inflammation.

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BACKGROUND: Lichen planus is a common disease, with a low malignant potential. There are several case reports in the literature of squamous cell carcinoma (SCC) developing in cutaneous lichen planuse. However, SCC developing in penile lichen planus is extremely rare. OBJECTIVE: To report a case of SCC developing within penile lichen planus, to discuss treatment with Mohs micrographic surgery, and to review the literature. METHOD: The diagnosis of lichen planus and SCC were made by biopsy of the lesion. RESULTS: We present the first case in the English literature of SCC developing within lichen planus of the penis. The lesion was treated with Mohs surgery and the patient's penis is functional and free of tumor 2 years postoperatively. CONCLUSION: Squamous cell carcinoma may develop within lichen planus. Treatment-resistant longstanding cases of lichen planus should be biopsied. Mohs micrographic surgery is a precise treatment for penile SCC, it avoids penectomy, and preserves normal function.

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Xeroderma pigmentosum is a group of rare autosomal recessive disorders with defective DNA repair that provide insight into the basic mechanism of carcinogenesis. It is the best human model linking clinical abnormalities and neoplasia to carcinogen exposure. We describe a patient with xeroderma pigmentosum and numerous basal cell carcinomas, squamous cell carcinomas, and melanomas treated with radiation therapy, Mohs micrographic surgery, dermabrasion, and isotretinoin prophylaxis.

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Forty-two male Sprague-Dawley rats were utilised to determine whether the angiogenic property of basic fibroblast growth factor (bFGF) could be applied to improve the survival of the ischaemic portion of a random skin flap and to accelerate the process of staged flap transfer. In the ischaemic flap model, bFGF enhanced the development of vascular connections between the bed and the flap and prevented marginally perfused areas from undergoing necrosis. No effect was observed in the staged reconstruction model using the same dosage of bFGF. A speculative explanation is given for the differential effect of BFGF in these two models. The application of angiogenic factors may improve the survival of the random portion of skin flaps. Further investigations are needed to determine whether exogenously applied angiogenic factors can have a beneficial effect in staged flap reconstructions.

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We report a case of cutaneous metastases from a scapular chondrosarcoma in a 85-year-old man. The metastatic skin lesion was noted nine years after resection of the primary tumor. Metastases to lung and soft tissues had occurred four years earlier. The patient also had a history of malignant melanoma. Although this case illustrates an unusual pattern of metastases, we conclude that the appearance of cutaneous lesions in a patient with a prior history of chondrosarcoma should alert the clinician to the possibility of a metastatic chondrosarcoma.

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The prevalence of low serum urea nitrogen concentrations (less than 50 mg/L) in our patient population was 1.2% (151 per 12,380 determinations), representing 95 individual cases. Of these, 81 of the patients' charts were located, reviewed, and classified into two groups, those with and those without hepatobiliary disease. Hepatobiliary disease was found in 36% of the 81 patients; 90% of these showed evidence of alcohol abuse, as did 19% of those without hepatobiliary disease. The remaining patients without hepatobiliary disease had various clinical conditions: psychiatric disorders (14.8%), overhydration (12.3%), endocrine disorders (7.4%), cardiovascular diseases (4.9%), prednisone administration (3.7%), and special diets (2.5%). Thus, in our patient population the most frequent cause of low serum urea nitrogen concentrations was alcohol abuse, found in about half of the cases.

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