However, an atypical phenotype does not rule out SMZL because 10% to 25% of SMZLs may express surface CD5.
Management of patients with SMZL depends on the disease status, the severity of the clinical presentation, and the presence of other comorbidities.
(44,45) However, splenic lymphoma with circulating villous lymphocytes has also been considered to be largely synonymous with SMZL, and precise discrimination of these disorders is challenging.
(46,47) It is important to once again note that cytoplasmic projections are not specific to a particular type of lymphoma, and, as described previously, they can be seen in SMZL, HCL, and HCL-v, as well as other low-grade B-cell neoplasms.
Similar to HCL-v and unlike most cases of SMZL, SDRPL cells frequently express DBA.
Treatment.--The clinical course of this provisional entity seems to be indolent and even more favorable than that of SMZL. (46) The discrimination between SDRPL and SMZL may not be possible on the basis of only the bone marrow and blood findings (7); however, therapeutic strategies for SDRPL do not differ from those of SMZL, and splenectomy solely to resolve uncertainty in classification is not suggested.
Lymphoplasmacytic lymphoma (LPL) is often in the differential diagnosis with SMZL because SMZL may exhibit plasmacytic differentiation, and LPL may sometimes be associated with splenomegaly.
(50) MYD88 mutations are infrequent in SMZL and other low-grade B-cell lymphomas, (51,52) and detection of a MYD88 mutation is a useful diagnostic adjunct in the appropriate clinical setting.
This was considered positive for involvement by SMZL. The bone marrow biopsy specimen was hypercellular with diffuse replacement of normal marrow elements by an infiltrate of small to medium-sized cells with moderate cytoplasm and occasional transformed cells consistent with involvement by SMZL.
(8) Unfortunately, well-defined treatment strategies in SMZL and other indolent lymphomas have not been described.
Select patients with SMZL have an aggressive course with death occurring within 1 year of diagnosis, despite surgical and chemotherapeutic intervention.
Patient selection appears critical in SMZL, since some patients have long-term survival, while others have early progression.