RESUMO
Objective To study the clinicopathological characteristics of complicated Kaposi's sarcoma after renal transplantation.Methods Five cases of complicated Kaposi's sarcoma after kidney transplantation were studied by histopathological immunohistochemical and ultrastructural observations.Results Of the 5 Kaposi's sarcoma patients,2 had multiple amaranthine dermal plaques starting on the legs,one had lymph node hypertrophy all over the body,and others had inguinal lymph node and adenoid hypertrophy. Histopathologically,these angiomatous lesions had characteristic areas of spindle cells within which erythrocytes were enmeshed.Admixed in these lesions were hyaline bodies and hemosider-laden,phagocytic cells.Immunohistochemical and ultrastructural studies revealed that this tumor was derived from vasofomative mesenchyme with multipotential capabilities.It was found that the epithelia and spindle cells were positive for Vimentin,CD-31,CD-34 and Ⅷ-RAg.Conclusion Complicated Kaposi's sarcoma after kidney transplantation can be diagnosed by combination of clinical manifestations and histopathological examinations with immunohistochemical and ultrastructural observations.