ABSTRACT
This chapter describes the types of the hematogenous tumors, including benign hematogenous lesions and malignant lymphomas and leukemia. It also describes the histopathology and differential diagnosis of some of the malignant lymphomas and leukemia, including T cell lymphomas, B cell lymphoma, plasmocytoma, Hodgkin's disease and leukemia. The chapter explains the cutaneous lymphomas and leukemias involving the nails and periungual skin. In recent years, malignant lymphomas have gained much interest in pathology, internal medicine, and dermatology. Whereas the number of publications concerning hair follicle involvement, often called pilotropic or folliculotropic lymphomas, is vast, those affecting the nail, ungueotropic lymphomas, are rare. Nail changes in cutaneous T cell lymphomas are unpredictable, often occur later in disease, affect several digits, and are mostly nonspecific, particularly in erythrodermic forms. Chronic lymphocytic leukemia typically occurs in elderly people and usually runs a protracted, relatively benign appearing course.
