A detailed study of CD34 antigen expression in the breast stroma with emphasis on changes observed in relation to normal breast and benign and malignant lesions. Besides determining whether loss of CD34 expression is specific to invasive disease, the book also aims to evaluate the prognostic significance of CD34 expression in the breast wherever possible . Use of CD34 as a marker of angiogenesis is also studied. A total of 317 cases are included. A brief review of literature is also provided.