RESUMO
Consumption of the epidermis associated with effacement of the rete ridge pattern has been cited as a useful criterion in the diagnosis of melanoma, but the significance of consumption in the absence of rete ridge effacement is unknown. We evaluated 701 melanocytic neoplasms for presence and 'grade' of consumption by melanocytic nests relative to diagnosis, body location, gender and age. We defined 1+ consumption as collections of melanocytes occupying greater than two thirds of the viable epidermis, with or without loss of the rete ridge pattern. Nests extending to the bottom of, within, and through the granular layer were graded 2+, 3+ and 4+, respectively. Consumption was more frequent and higher grades were found in melanomas followed by Spitz nevi compared with conventional melanocytic nevi (p < 0.001). Melanomas with higher Breslow thickness showed higher grades (p < 0.05). In conventional nevi, consumption occurred most frequently in back (13.7%), acral (11.9%) and scalp (9.8%) locations. Consumption without the requirement for rete ridge effacement occurs more frequently and at higher grades in melanoma. Higher grades correlate with higher Breslow thickness. Consumption is also common in Spitz nevi and occurs at lower grades in conventional (non-Spitz) nevi, especially on the back, the scalp and at acral sites.
Assuntos
Dor Abdominal/diagnóstico , Vasculite por IgA/diagnóstico , Biópsia , Criança , Diagnóstico Diferencial , Feminino , HumanosRESUMO
In early-stage cutaneous T-cell lymphoma (CTCL), malignant T cells are confined to skin and are difficult to isolate and discriminate from benign reactive cells. We found that T cells from CTCL skin lesions contained a population of large, high-scatter, activated skin homing T cells not observed in other inflammatory skin diseases. High-scatter T (T(HS)) cells were CD4(+) in CD4(+) mycosis fungoides (MF), CD8(+) in CD8(+) MF, and contained only clonal T cells in patients with identifiable malignant Vß clones. T(HS) cells were present in the blood of patients with leukemic CTCL, absent in patients without blood involvement, and contained only clonal malignant T cells. The presence of clonal T(HS) cells correlated with skin disease in patients followed longitudinally. Clonal T(HS) cells underwent apoptosis in patients clearing on extracorporeal photopheresis but persisted in nonresponsive patients. Benign clonal T-cell proliferations mapped to the normal low-scatter T-cell population. Thus, the malignant T cells in both MF and leukemic CTCL can be conclusively identified by a unique scatter profile. This observation will allow selective study of malignant T cells, can be used to discriminate patients with MF from patients with other inflammatory skin diseases, to detect peripheral blood involvement, and to monitor responses to therapy.
Assuntos
Linfoma Cutâneo de Células T/imunologia , Linfoma Cutâneo de Células T/patologia , Neoplasias Cutâneas/imunologia , Neoplasias Cutâneas/patologia , Subpopulações de Linfócitos T/imunologia , Subpopulações de Linfócitos T/patologia , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD4-Positivos/metabolismo , Linfócitos T CD4-Positivos/patologia , Linfócitos T CD8-Positivos/imunologia , Linfócitos T CD8-Positivos/metabolismo , Linfócitos T CD8-Positivos/patologia , Proliferação de Células , Separação Celular , Proteínas de Escherichia coli , Citometria de Fluxo , Fatores de Transcrição Forkhead/metabolismo , Genes Codificadores da Cadeia beta de Receptores de Linfócitos T , Humanos , Ativação Linfocitária , Linfoma Cutâneo de Células T/genética , Linfoma Cutâneo de Células T/metabolismo , Micose Fungoide/genética , Micose Fungoide/imunologia , Micose Fungoide/metabolismo , Micose Fungoide/patologia , Estadiamento de Neoplasias , Neoplasias Cutâneas/genética , Neoplasias Cutâneas/metabolismo , Subpopulações de Linfócitos T/metabolismo , Linfócitos T Reguladores/imunologia , Linfócitos T Reguladores/metabolismo , Linfócitos T Reguladores/patologia , Fatores de TranscriçãoRESUMO
The transient receptor potential cation channel, subfamily M, member 1 (TRPM1/Melastatin-1/MLSN-1) expression has been shown to have prognostic utility in the evaluation of primary cutaneous melanoma. We analyzed a series of spindled and epithelioid cell nevi (Spitz) and primary cutaneous nodular melanomas to determine whether the expression of TRPM1 mRNA may be useful in distinguishing between Spitz nevi and nodular melanomas and to further examine the patterns of TRPM1 mRNA expression in cutaneous melanocytic proliferations. Formalin-fixed, paraffin-embedded tissues from 95 Spitz nevi and 33 nodular melanomas were analyzed for the expression of TRPM1 mRNA by in situ hybridization using (35)S-labeled riboprobes. Ubiquitous melanocytic expression of TRPM1 mRNA was observed in 56 of 95 (59%) Spitz nevi and 4 of 33 (12%) nodular melanomas. Diffusely scattered loss of TRPM1 mRNA was identified in 38 of 95 (40%) Spitz nevi and 2 of 33 (6%) nodular melanomas. Regional loss of the TRPM1 mRNA expression by a significant subset of dermal tumor cells or a complete absence of TRPM1 expression by the dermal tumor was identified in 27 of 33 (82%) nodular melanomas, but only 1 of 95 (1%) Spitz nevi. These findings suggest that the pattern of TRPM1 mRNA expression may be helpful in the differentiation of Spitz nevi and nodular melanomas. Of the 16 patients who experienced metastasis, 15 (94%) had primary tumors that displayed reduced MLSN mRNA expression by all or a part of the dermal tumor.
