Chapter 105. Malignancies of Lymphoid Cells (Part 20)

Other B Cell Lymphoid MalignanciesB cell prolymphocytic leukemia involves blood and marrow infiltration by large lymphocytes with prominent nucleoli. Patients typically have a high white cell count, splenomegaly, and minimal lymphadenopathy. The chances for a complete response to therapy are poor.Hairy cell leukemia is a rare disease that presents predominantly in older males. Typical presentation involves pancytopenia, although occasional patients will have a leukemic presentation. Splenomegaly is usual. The malignant cells appear to have "hairy" projections on light and electron microscopy and show acharacteristic staining pattern with tartrate-resistant acid phosphatase. ...
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Chapter 105. Malignancies of Lymphoid Cells (Part 20) Chapter 105. Malignancies of Lymphoid Cells (Part 20) Other B Cell Lymphoid Malignancies B cell prolymphocytic leukemia involves blood and marrow infiltration bylarge lymphocytes with prominent nucleoli. Patients typically have a high whitecell count, splenomegaly, and minimal lymphadenopathy. The chances for acomplete response to therapy are poor. Hairy cell leukemia is a rare disease that presents predominantly in oldermales. Typical presentation involves pancytopenia, although occasional patientswill have a leukemic presentation. Splenomegaly is usual. The malignant cellsappear to have hairy projections on light and electron microscopy and show acharacteristic staining pattern with tartrate-resistant acid phosphatase. Bonemarrow is typically not able to be aspirated, and biopsy shows a pattern of fibrosiswith diffuse infiltration by the malignant cells. Patients with this disorder areprone to unusual infections, including infection by Mycobacterium aviumintracellulare, and to vasculitic syndromes. Hairy cell leukemia is responsive tochemotherapy with interferon α, pentostatin, or cladribine, with the latter being theusually preferred treatment. Clinical complete remissions with cladribine occur inthe majority of patients, and long-term disease-free survival is frequent. Splenic marginal zone lymphoma involves infiltration of the splenic whitepulp by small, monoclonal B cells. This is a rare disorder that can present asleukemia as well as lymphoma. Definitive diagnosis is often made at splenectomy,which is also an effective therapy. This is an extremely indolent disorder, butwhen chemotherapy is required, the most usual treatment has been chlorambucil. Lymphoplasmacytic lymphoma is the tissue manifestation of Waldenströmsmacroglobulinemia (Chap. 106). This type of lymphoma has been associated withchronic hepatitis C virus infection, and an etiologic association has been proposed.Patients typically present with lymphadenopathy, splenomegaly, bone marrowinvolvement, and occasionally peripheral blood involvement. The tumor cells donot express CD5. Patients often have a monoclonal IgM protein, high levels ofwhich can dominate the clinical picture with the symptoms of hyperviscosity.Treatment of lymphoplasmacytic lymphoma can be aimed primarily at reducingthe abnormal protein, if present, but will usually also involve chemotherapy.Chlorambucil, fludarabine, and cladribine have been utilized. The median 5-yearsurvival for patients with this disorder is ~60%. Nodal marginal zone lymphoma, also known as monocytoid B celllymphoma, represents ~1% of non-Hodgkins lymphomas. This lymphoma has aslight female predominance and presents with disseminated disease (i.e., stage IIIor IV) in 75% of patients. Approximately one-third of patients have bone marrowinvolvement, and a leukemic presentation occasionally occurs. The stagingevaluation and therapy should use the same approach as used for patients withfollicular lymphoma. Approximately 60% of the patients with nodal marginal zonelymphoma will survive 5 years after diagnosis. Precursor Cell T Cell Malignancies Precursor T Cell Lymphoblastic Leukemia/Lymphoma Precursor T cell malignancies can present either as ALL or as an aggressivelymphoma. These malignancies are more common in children and young adults,with males more frequently affected than females. Precursor T cell ALL can present with bone marrow failure, although theseverity of anemia, neutropenia, and thrombocytopenia is often less than inprecursor B cell ALL. These patients sometimes have very high white cell counts,a mediastinal mass, lymphadenopathy, and hepatosplenomegaly. Precursor T celllymphoblastic lymphoma is most often found in young men presenting with alarge mediastinal mass and pleural effusions. Both presentations have a propensityto metastasize to the CNS, and CNS involvement is often present at diagnosis. Precursor T Cell Lymphoblastic Leukemia/Lymphoma: Treatment Children with precursor T cell ALL seem to benefit from very intensiveremission induction and consolidation regimens. The majority of patients treatedin this manner can be cured. Older children and young adults with precursor T celllymphoblastic lymphoma are also often treated with leukemia-like regimens.Patients who present with localized disease have an excellent prognosis. However,advanced age is an adverse prognostic factor. Adults with precursor T celllymphoblastic lymphoma who present with high LDH levels or bone marrow orCNS involvement are often offered bone marrow transplantation as part of theirprimary therapy. Mature (Peripheral) T Cell Disorders Mycosis F ...