Classification and Origin
Lymphoid neoplasms are divided into precursor cell neoplasms and mature peripheral cell neoplasms. Neoplasms of mature cells are clinically subdivided into disseminated leukemias, predominantly nodal forms, and primary extranodal variants.
B-cell chronic lymphocytic leukemia is classified as a mature B-cell neoplasm. Its key markers include CD19, CD20, and CD23 antigens, as well as surface immunoglobulins. Chromosomal aberrations are detected in half of patients, with trisomy 12 being the most common.
Lymph Node and Spleen Changes
Macroscopically, lymph nodes are generalized, enlarged, and fused into massive soft or firm conglomerates that appear juicy, pinkish-white, and homogeneous on cross-section. Microscopic examination reveals loss of nodal architecture and the formation of solid masses of lymphocytes with proliferation centers composed of large prolymphocytes.
The spleen is significantly enlarged with increased weight and a fleshy consistency, appearing dark red on cross-section. Organ infiltration develops in stages: follicles are affected first, followed by proliferation of pathological elements in the red pulp, involving vessel walls, trabeculae, and the capsule.
Involvement of the Liver, Kidneys, and Bone Marrow
In the bone marrow of flat and tubular bones, the tissue retains its red color, with patches of yellow marrow preserved in the diaphysis of tubular bones—a feature distinguishing this condition from myeloid leukemia. In severe cases, diffuse replacement of myeloid tissue occurs.
The liver is enlarged and firm, showing small gray-white nodules on cross-section. Microscopic evaluation demonstrates lymphocytic infiltration along portal tracts, while hepatocytes undergo protein or fatty degeneration. The kidneys are enlarged with a firm consistency and a grayish-brown color due to marked leukemic infiltration.
Complications
The clinical course is complicated by secondary infections such as pneumonia. Hemolytic conditions may develop, leading to hemolytic jaundice and generalized hemosiderosis.
Compression syndromes pose a particular danger: compression of the heart, trachea, and esophagus by enlarged mediastinal lymph nodes, as well as impaired blood outflow in the portal venous system due to mesenteric node involvement, resulting in portal hypertension and ascites.