Gertz, Morie A.

Abstract This study examined the prognostic value of circulating peripheral blood plasma cells (PBPCs) in patients with primary systemic amyloidosis (AL). A sensitive slide-based immunofluorescence technique was used to assess 147 patients for circulating PBPCs. Circulating monoclonal plasma cells were quantified as a percentage of circulating cytoplasmic immunoglobulin-positive cells (PBPC%). The absolute circulating plasma cell count was also determined. When analyzed retrospectively, 24 (16%) of 147 patients were found to have detectable circulating PBPCs. Overall survival for patients with high PBPC%'s (> 1%) was poorer (median survival, 10 vs 29 months;P = .002). Similarly, overall survival for patients with high PBPC counts (> 0.5 × 106/L) was significantly poorer (median, 13 vs 31 months;P = .003). Increased percentages of bone marrow plasma cells (BMPC%; P = .0004), increased levels of serum β2-microglobulin (P = .04), and dominant cardiac amyloid involvement (P = .03) also predicted poorer survival. The combined consideration of circulating PBPCs and BMPC% identified low-, intermediate-, and high-risk groups with median survivals of 37.5, 15.5, and 10 months, respectively (P = .0003). Multivariate analysis revealed circulating PBPCs and BMPC% to be independent prognostic factors for survival. Patients with PBPC%'s of 2% or higher were significantly more likely to have a coexisting clinical diagnosis of multiple myeloma (50% vs 12%, P = .008). The prognostic value of circulating PBPCs may help select treatment for patients with AL.

PURPOSE: Multiple myeloma is a malignancy of plasma cells and is characterized by increased marrow angiogenesis. Thalidomide, an agent with antiangiogenic properties, is effective in relapsed myeloma. We report the results of a study combining thalidomide and dexamethasone as initial therapy for myeloma. PATIENTS AND METHODS: Fifty patients with newly diagnosed myeloma were studied. Thalidomide was given at a dose of 200 mg/d orally. Dexamethasone was given at a dose of 40 mg/d orally on days 1 to 4, 9 to 12, and 17 to 20 (odd cycles) and 40 mg/d on days 1 to 4 (even cycles), repeated monthly. RESULTS: Of all 50 patients, a confirmed response was seen in 32 patients yielding a response rate of 64% (95% confidence interval, 49% to 77%). Thirty-one patients (62%) proceeded to stem-cell collection after four cycles of therapy including 26 who underwent stem-cell transplantation and five who chose stem-cell cryopreservation. Major grade 3 or 4 toxicities were observed in 16 patients (32%), and the most frequent were deep vein thrombosis (six patients), constipation (four patients), rash (three patients), and dyspnea (two patients). Three deaths occurred during active therapy because of a pancreatitis, pulmonary embolism, and infection. CONCLUSION: We conclude that the combination of thalidomide plus dexamethasone is a feasible and active regimen in the treatment of multiple myeloma. It merits further study as an oral alternative to infusional chemotherapy with vincristine, doxorubicin, and dexamethasone and other intravenous regimens currently used as pretransplantation induction therapy for myeloma.

High-dose melphalan with autologous blood stem cell transplantation (SCT) can reverse the disease process in selected patients with primary systemic amyloidosis (AL); however, SCT for AL remains controversial because of the treatment-related mortality in patients with cardiac and multisystem organ involvement. In this review, we briefly discuss recent advances in AL, such as the free light-chain assay and the role of immunoglobulin light-chain variable region germline genes in the disease, and then we discuss the current status of SCT for AL with emphases on patient selection, approaches to stem cell mobilization, and peri-SCT management. It is clear that patients with AL who have advanced amyloid cardiomyopathy or more than 2 major viscera involved with disease are poor candidates for SCT. Therefore, the importance of patient selection cannot be overemphasized, and patients with 1 or 2 involved organs or with early cardiac involvement are usually appropriate candidates for SCT. Because the toxicity of melphalan is dose-related and survival with AL may be age-related, patient age and the extent of organ involvement can provide a basis for patient stratification. We discuss such a risk-adapted approach to melphalan dosing in detail and conclude with a brief overview of current research using SCT to treat patients with AL.

Primary systemic amyloidosis (AL) is a plasma cell (PC) dyscrasia with clinical similarities to multiple myeloma (MM) and monoclonal gammopathy of undetermined significance (MGUS), but its molecular basis is poorly understood. Translocations at the immunoglobulin heavy-chain (IgH) locus, 14q32, are likely early genetic events in both MM and MGUS and involve several nonrandom, recurrent, partner chromosomes such as 11q13, 16q23, and 4p16.3. Given the similarities between MM, MGUS, and AL, bone marrow clonal PCs were evaluated in 29 patients with AL using interphase fluorescence in situ hybridization (FISH) combined with immunofluorescence detection of the cytoplasmic light-chain (cIg-FISH) for the presence of 14q32 translocations and the t(11;14)(q13;q32). Of 29 patients studied, 21 (72.4%) showed results compatible with the presence of a 14q32 translocation, and 16 (76.2%) of those had translocation (11;14)(q13;q32) for an overall prevalence of the abnormality of 55%. IgH translocations are common in AL, especially the t(11;14)(q13;q32).

AbstractAutologous stem cell transplantation (ASCT) improves survival in patients with previously untreated multiple myeloma (MM) and relapsed, chemotherapy-sensitive, aggressive non-Hodgkin lymphoma (NHL). Lower relapse rates seen in allogeneic stem cell transplantation have been related to early absolute lymphocyte count (ALC) recovery as a manifestation of early graft-verus-tumor effect. In ASCT, the relation between ALC recovery and clinical outcomes in MM and NHL was not previously described. This is a retrospective study of patients with MM and NHL who underwent ASCT at the Mayo Clinic between 1987 and 1999. The ALC threshold was determined at 500 cells/μL on day 15 after ASCT. The study identified 126 patients with MM and 104 patients with NHL. The median overall survival (OS) and progression-free survival (PFS) times for patients with MM were significantly longer in patients with an ALC of 500 cells/μL or more than patients with an ALC of fewer than 500 cells/μL (33 vs 12 months,P < .0001; 16 vs 8 months, P < .0003, respectively). For patients with NHL, the median OS and PFS times were significantly longer in patients with an ALC of 500 cells/μL or more versus those with fewer than 500 cells/μL (not reached vs 6 months, P < .0001; not reached vs 4 months,P < .0001, respectively). Multivariate analysis demonstrated day 15 ALC to be an independent prognostic indicator for OS and PFS rates for both groups of patients. In conclusion, ALC is correlated with clinical outcome and requires further study.

AbstractCurrent information on Waldenström macroglobulinemia (WM) is based on retrospective or single-institution studies of patients requiring therapy. Between 1992 and 1998, 231 patients with WM were enrolled in a prospective observational multicenter clinical trial. Of these, 182 patients with symptomatic or progressive disease were treated with 4 to 8 cycles of therapy with a purine nucleoside analogue, fludarabine (FAMP; 30 mg/m2 of body-surface area daily for 5 days every 28 days). A serum β2-microglobulin (β2M) level below 3 mg/L and a hemoglobin level of at least 120 g/L (12 g/dL) at presentation predicted a lower likelihood of requiring therapy. The overall rate of response to FAMP therapy was 36% (95% confidence interval, 29%-44%), with 2% complete remissions. Patients who were 70 years old or older had a substantially lower likelihood of response (odds ratio, 0.34; P = .004) than younger patients. On multivariate analysis, a serum β2M level of 3 mg/L or higher, hemoglobin level below 120 g/L, and serum IgM level below 40 g/L [4 g/dL] were significant adverse prognostic factors for survival. We developed a simple staging system for WM by using these variables and identified 4 distinct subsets of patients with estimated 5-year overall survival rates of 87%, 64%, 53%, and 22%, and 5-year progression-free survival rates of 83%, 55%, 33%, and 12%. Prognosis in WM is highly variable and serum β2M was the dominant predictor of a need for therapy and of survival. FAMP has activity against WM. Our staging system may provide guidance for a risk-based approach to the treatment of WM.

Abstract The plasma cell labeling index (PCLI) is a measure of plasma cell proliferative activity and is an important prognostic factor in newly diagnosed multiple myeloma (MM). Occasionally patients have been observed with stable, plateau phase MM with minimal numbers of residual light-chain–restricted monoclonal plasma cells, but a high PCLI. No data are available on the outcomes for such patients. Data from 57 patients with plateau phase MM and a marrow PCLI of more than 1.0% were compared with 105 matched control patients with MM with a marrow PCLI of less than 1.0%. All patients had less than 10% total plasma cells on marrow aspirate and biopsy. The median time to progression and overall survival were 8 months and 20 months, respectively, in the high PCLI group versus 39 months and 56 months, respectively, in the low PCLI group (P < .0001). These findings suggest that a high PCLI in patients with apparently stable, plateau phase MM is an adverse parameter that may predict a short time to disease progression and death.

AbstractThe course of clonal evolution of 2 related clones in the blood of a patient with Waldenstrom macroglobulinemia (WM) indicates the functional importance for the expression of the B-cell receptor for the survival of these malignant cells. Protein and nucleotide sequencing of the paraproteins' variable regions revealed 2 predominant Vλ and 2 VH sequences, each set comprised in the ratio 1:1.5. The 2 VH sequences and 2 Vλ sequences shared the same VDJ and VJ junctional sequences, respectively, indicating that 2 malignant clones had evolved from a common ancestor. This is the first report on intraclonal heterogeneity in WM. Comparison of the Vλ and VH sequences with the closest matching known germline genes showed that they contained approximately 10 somatic mutations each. The distribution and type of mutations demonstrate that mutations have continued to accumulate in the malignant clones and that selection has been operating to preserve immunoglobulin structure.