In 1982, results of a consensus study were published as the Working Formulation. The Working Formulation combined results from six major classification systems into one classification.This allowed comparison of studies from different institutions and countries.Lymphoplasmacytic lymphoma is usually associated with a monoclonal serum paraprotein of immunoglobulin M (Ig M) type (Waldenström macroglobulinemia). Most patients have bone marrow, lymph node, and splenic involvement, and some patients may develop hyperviscosity syndrome.Other lymphomas may also be associated with serum paraproteins.Asymptomatic patients can be monitored for evidence of disease progression without immediate need for chemotherapy.[9,30,31] Prognostic factors associated with symptoms requiring therapy include the following: The management of lymphoplasmacytic lymphoma is similar to that of other low-grade lymphomas, especially diffuse, small lymphocytic lymphoma/chronic lymphocytic leukemia.[30,32-34] If the viscosity relative to water is greater than four, the patient may have manifestations of hyperviscosity.
Thus, European and American pathologists have proposed a new classification, the Revised European American Lymphoma (REAL) classification.[5-8] Since 1995, members of the European and American Hematopathology societies have been collaborating on a new World Health Organization (WHO) classification, which represents an updated version of the REAL system.[9,10] The WHO modification of the REAL classification recognizes three major categories of lymphoid malignancies based on morphology and cell lineage: B-cell neoplasms, T-cell/natural killer (NK)-cell neoplasms, and Hodgkin lymphoma (HL).
The Rappaport classification, which also follows, is no longer in common use.
As the understanding of NHL has improved and as the histopathologic diagnosis of NHL has become more sophisticated with the use of immunologic and genetic techniques, a number of new pathologic entities have been described. In addition, the understanding and treatment of many of the previously described pathologic subtypes have changed.
Patients who present with or convert to aggressive forms of NHL may have sustained complete remissions with combination chemotherapy regimens or aggressive consolidation with marrow or stem cell support.[5,6] Late effects of treatment for non-Hodgkin lymphoma (NHL) have been observed.
Pelvic radiation therapy and large cumulative doses of cyclophosphamide have been associated with a high risk of permanent sterility. For as many as three decades after diagnosis, patients are at a significantly elevated risk for second primary cancers, especially the following:[1-3] Left ventricular dysfunction was a significant late effect in long-term survivors of high-grade NHL who received more than 200 mg/m² of doxorubicin.[4,5] Myelodysplastic syndrome and acute myelogenous leukemia are late complications of myeloablative therapy with autologous bone marrow or peripheral blood stem cell support, as well as conventional chemotherapy-containing alkylating agents.[1,6-13] Most of these patients show clonal hematopoiesis even before the transplantation, suggesting that the hematologic injury usually occurs during induction or reinduction chemotherapy.[8,14,15] With a median 10-year follow-up after autologous bone marrow transplantation (BMT) with conditioning using cyclophosphamide and total-body radiation therapy, in a series of 605 patients, the incidence of a second malignancy was 21%, and 10% of those were solid tumors. Successful pregnancies with children born free of congenital abnormalities have been reported in young women after autologous BMT. Some patients have osteopenia or osteoporosis at the start of therapy; bone density may worsen after therapy for lymphoma. A pathologist should be consulted before a biopsy because some studies require special preparation of tissue (e.g., frozen tissue).