■ Introduction Bone marrow failure syndromes, defined as peripheral cytopenias due to decreased hematopoiesis in the bone marrow, may be divided into acquired and inherited conditions and further divided into disorders that alter only one hematopoietic lineage (erythroids, myeloids, or…
■ Normal Lymph Node Anatomy Normal lymph nodes are typically bean shaped. They have, beginning at their periphery and moving centrally, a fibrous capsule, a cortex, a paracortex, a medulla, and a hilus. The cortex, a B-cell–predominant area, contains follicles.…
■ Introduction A variety of morphologic changes can occur in non-neoplastic white blood cells (WBCs). Some reflect nonspecific reactive changes, whereas others are specific and are associated with clinically significant disorders. In this chapter we review non-neoplastic changes representing a…
Basic Physiology of Hemostasis and Fibrinolysis Physiologic hemostasis is initiated with injury to a blood vessel wall. This triggers a sequence of reactions involving plasma proteins, platelets, extracellular membrane components, and the vascular smooth muscle to ultimately form a stable…
■ Introduction The disorders of red blood cells can be divided into those of decreased red blood cell (RBC) mass (anemias) and those of increased RBC mass (erythrocytoses). Most of this chapter is devoted to various types of anemias, with…
The spectrum of lymphomas encountered in extranodal sites differ from those encountered in lymph nodes ( Tables 61-1 and 61-2 ). Many of the lymphomas that involve extranodal sites are described as specific pathologic entities in other chapters. This chapter…
Few hematologic malignancies arise primarily in the spleen; most conditions occurring at this site represent secondary involvement by diseases originating elsewhere in the body. The role of the pathologist in most cases is to confirm the known or suspected diagnosis…
Non-lymphoid elements are frequently present in surgically excised lymph nodes. This chapter reviews the most commonly encountered tumors and non-neoplastic lesions, especially those that can mimic lymphoma, and provides an update on studies useful in distinguishing them. The chapter begins…
Definition The bone marrow, the primary site of hematopoiesis, may contain hematopoietic or non-hematopoietic tumors and also frequently reflects metabolic disturbances. The occurrence of bone marrow metastases is strongly influenced by microenvironmental factors that favor the engraftment of certain malignancies.…
General Approach A great number of changes occur in the bone marrow during and after therapy for malignancy. Although proper interpretation of these changes requires knowledge of the patient's original disease process, some general features are common to all cases.…