Sunlight and psoralen and ultraviolet A (PUVA) are risk factors for the development of squamous cell carcinoma (SCC) and, to a lesser extent, basal cell carcinoma (BCC). Ultraviolet B (UVB) therapy, used for the treat...Sunlight and psoralen and ultraviolet A (PUVA) are risk factors for the development of squamous cell carcinoma (SCC) and, to a lesser extent, basal cell carcinoma (BCC). Ultraviolet B (UVB) therapy, used for the treatment of psoriasis, might also increase the risk of these tumors. We studied the relation of skin cancer incidence to UVB use among 1380 adult subjects enrolled in a long- term safety trial of PUVA therapy. We used negative binomial regression models to quantify the association between UVB and the development of non- melanoma skin cancer (NMSC), controlling for known confounders. High UVB exposure(≥ 300treatmentsvs<300 treatments) was associated with a modest but significant increase in SCC (adjusted incidence rate ratio (IRR)=1.37, 95% confidence interval (CI)=1.03- 1.83) and BCC (adjusted IRR=1.45, 95% CI=1.071.96) risk. Among patients with<100 PUVA treatments, high UVB exposure was significantly associated with the development of SCC (adjusted IRR=2.75, 95% CI=1.11- 6.84) and BCC (adjusted IRR=3.00, 95% CI=1.30- 6.91) on body sites typically exposed to UVB therapy but not on chronically sun- exposed sites typically covered during therapy. For adults with high UVB exposure levels, UVB confers a modest increase in NMSC risk, much less than that observed with PUVA. Therefore, UVB remains a relatively low- risk treatment for psoriasis.展开更多
Background: Apoptosis is important for maintenance of tissue homeostasis and often dysregulated in cutaneous neoplasms. The apoptosis inhibitor survivin is expressed in melanoma and non-melanoma skin cancers and benig...Background: Apoptosis is important for maintenance of tissue homeostasis and often dysregulated in cutaneous neoplasms. The apoptosis inhibitor survivin is expressed in melanoma and non-melanoma skin cancers and benign keratinocytic lesions. Its expression has not been studied in melanocytic nevi. Objective: We determined the expression pattern of survivin in benign melanocytic nevi in comparison to markers of proliferation and apoptosis. Methods: Six cases of each of the following melanocytic nevi were retrieved from a dermatopathology archive: compound dysplastic nevus, intradermal nevus, compound nevus, neurotized intradermal nevus, and Spitz nevus. Survivin expression was evaluated by in situ hybridization. Apoptotic and proliferation indices were calculated by counting immunoreactive cells in terminal deoxynucleotidyl transferase (TdT)- mediated dUTP nick end labeling and proliferating cell nuclear antigen immunostained sections, respectively. Results: All nevi, regardless of histologic type, expressed survivin. Compound melanocytic lesions expressed survivin in both epidermal and dermal compartments. The apoptotic rate was low for dysplastic, compound, and Spitz nevi, and apoptotic cells were not identified in any neurotized nevus. The proliferative index was highest for Spitz nevi, while all other nevi demonstrated rare positive cells. Conclusions: Survivin is consistently expressed in benign melanocytic lesions, while apoptotic cells are rarely identified, suggesting the dysregulation of apoptotic pathways with the accumulation of cells in these neoplasms.展开更多
文摘Sunlight and psoralen and ultraviolet A (PUVA) are risk factors for the development of squamous cell carcinoma (SCC) and, to a lesser extent, basal cell carcinoma (BCC). Ultraviolet B (UVB) therapy, used for the treatment of psoriasis, might also increase the risk of these tumors. We studied the relation of skin cancer incidence to UVB use among 1380 adult subjects enrolled in a long- term safety trial of PUVA therapy. We used negative binomial regression models to quantify the association between UVB and the development of non- melanoma skin cancer (NMSC), controlling for known confounders. High UVB exposure(≥ 300treatmentsvs<300 treatments) was associated with a modest but significant increase in SCC (adjusted incidence rate ratio (IRR)=1.37, 95% confidence interval (CI)=1.03- 1.83) and BCC (adjusted IRR=1.45, 95% CI=1.071.96) risk. Among patients with<100 PUVA treatments, high UVB exposure was significantly associated with the development of SCC (adjusted IRR=2.75, 95% CI=1.11- 6.84) and BCC (adjusted IRR=3.00, 95% CI=1.30- 6.91) on body sites typically exposed to UVB therapy but not on chronically sun- exposed sites typically covered during therapy. For adults with high UVB exposure levels, UVB confers a modest increase in NMSC risk, much less than that observed with PUVA. Therefore, UVB remains a relatively low- risk treatment for psoriasis.
文摘Background: Apoptosis is important for maintenance of tissue homeostasis and often dysregulated in cutaneous neoplasms. The apoptosis inhibitor survivin is expressed in melanoma and non-melanoma skin cancers and benign keratinocytic lesions. Its expression has not been studied in melanocytic nevi. Objective: We determined the expression pattern of survivin in benign melanocytic nevi in comparison to markers of proliferation and apoptosis. Methods: Six cases of each of the following melanocytic nevi were retrieved from a dermatopathology archive: compound dysplastic nevus, intradermal nevus, compound nevus, neurotized intradermal nevus, and Spitz nevus. Survivin expression was evaluated by in situ hybridization. Apoptotic and proliferation indices were calculated by counting immunoreactive cells in terminal deoxynucleotidyl transferase (TdT)- mediated dUTP nick end labeling and proliferating cell nuclear antigen immunostained sections, respectively. Results: All nevi, regardless of histologic type, expressed survivin. Compound melanocytic lesions expressed survivin in both epidermal and dermal compartments. The apoptotic rate was low for dysplastic, compound, and Spitz nevi, and apoptotic cells were not identified in any neurotized nevus. The proliferative index was highest for Spitz nevi, while all other nevi demonstrated rare positive cells. Conclusions: Survivin is consistently expressed in benign melanocytic lesions, while apoptotic cells are rarely identified, suggesting the dysregulation of apoptotic pathways with the accumulation of cells in these neoplasms.