and neck and upper extremities, especially in light-skinned individuals with blue eyes and blonde or red hair.3,4,7 Exposure to sunshine is not the only etiologic factor. A surprisingly high incidence of SCCs is recorded from areas of low sunlight in some northern countries and may be related to malignant change in papillomavirus-induced warts, under the influence of immunosuppression, sunlight, HLA-antigens and other factors.3,4 The incidence of cutaneous malignancies increases with length of follow-up after transplantation, as demonstrated in a Dutch study that showed a 10% incidence of nonmelanoma skin cancer at 10 years posttransplantation, that rose to 40% after 20 years.3,4

Skin tumors in transplant patients show several unusual features compared with similar lesions in the general population.3-5,7 Whereas basal cell carcinomas (BCCs) outnumber SCCs in the general population by 5 to 1, in transplant recipients SCCs outnumber BCCs by 1.8 to 1. SCC is estimated to occur at a frequency between 40 and 250 times higher than in the general population, BCC ten times higher and malignant melanoma five times more commonly than expected. In the general population SCCs occur mostly individuals in their 60s and 70s, but the average age of transplant patients is 30 years younger. In addition, the frequency of multiple skin malignancies in the CTTR is remarkably high (43%) and, despite being a worldwide collection, is similar to that seen only in areas of copious sunlight. Some patients each have more than 100 skin tumors. In some patients there is an apparently widespread cutaneous abnormality with areas of unstable epithelium containing multifocal premalignant and malignant lesions.7 In the general population most lymph node metastases and deaths from skin malignancies are caused by melanomas. In contrast SCCs are much more aggressive in transplant patients than in the general population and account for the majority of lymph node metastases and deaths from skin cancer.3,4 Thus, nearly 6% of patients with skin neoplasms in the CTTR have lymph node metastases. Of these 73% are from SCCs and only 17% from melanomas. Similarly 5% of patients die of skin cancer, with 60% of deaths being from SCC and only 30% from melanomas.3,4

Among the PTLDs, Hodgkin's disease and plasmacytoma/myeloma are much less common than in the general population3,4 and most tumors represent a broad spectrum of lesions ranging from benign hyperplasias, such as infectious mono-nucleosis-like disorders at one end to frankly malignant lymphomas at the other extreme.8,9

The majority of PTLDs arise from B-lymphocytes but CTTR data indicate that 15% arise from T-lymphocytes, while rare cases are of null cell origin. In approximately 80-90% of PTLDs infection with Epstein-Barr virus (EBV) plays an important role.8,9 Patients at particular risk for devoloping EBV-related PTLD are young children who are EBV negative pretransplantation but subsequently become seropositive.3,4,8,9 Recipients of nonrenal organs are at higher risk for developing PTLD as they generally tend to be more heavily immunosuppressed than renal allograft recipients.3,4

PTLDs differ from lymphomas in the general population in several respects.3,4 Whereas extra-nodal involvement occurs in from 24-48% of

How To Prevent Skin Cancer

How To Prevent Skin Cancer

Complete Guide to Preventing Skin Cancer. We all know enough to fear the name, just as we do the words tumor and malignant. But apart from that, most of us know very little at all about cancer, especially skin cancer in itself. If I were to ask you to tell me about skin cancer right now, what would you say? Apart from the fact that its a cancer on the skin, that is.

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