Fonseca, Rafael

AbstractLight chain–associated amyloidosis (AL) is a plasma cell dyscrasia in which the secreted monoclonal immunoglobulin (Ig) light chains form amyloid fibrils. There is considerable heterogeneity in clinical presentation, and prognosis of the disease relates to the severity of organ dysfunction induced by amyloid deposits. The mechanisms by which the amyloid fibrils are deposited as well as the predilection for specific organ sites have not been clearly elucidated. This study characterizes the repertoire of immunoglobulin light chain variable genes used by the clonal B cell in AL amyloid patients, and the association of light chain variable region (VL) genes with clinical presentation and outcome is assessed in 58 (32 λ and 26 κ) patients. A preferential use of VL germ-line genes was noted for both AL κ and λ patients. There was a significant correlation between the use of the Vλ VI germ-line donor, 6a, and renal involvement as well as the Vλ III gene, 3r, with soft-tissue AL. The use of a biased VL gene repertoire also correlated with clinical outcome, revealing important trends for predicting prognosis. The use of Vλ II germ-line genes was associated with cardiac amyloidosis and affected survival adversely. The presence of multiple myeloma also correlated with a poor prognosis. The presence of renal disease, on the other hand, was associated with improved survival. Therefore, identification of the clonal VL gene in AL has important implications in determining clinical outcome.

The POEMS syndrome (coined to refer to polyneuropathy, organomegaly, endocrinopathy, M protein, and skin changes) remains poorly understood. Ambiguity exists over the features necessary to establish the diagnosis, treatment efficacy, and prognosis. We identified 99 patients with POEMS syndrome. Minimal criteria were a sensorimotor peripheral neuropathy and evidence of a monoclonal plasmaproliferative disorder. To distinguish POEMS from neuropathy associated with monoclonal gammopathy of undetermined significance, additional criteria were included: a bone lesion, Castleman disease, organomegaly (or lymphadenopathy), endocrinopathy, edema (peripheral edema, ascites, or effusions), and skin changes. The median age at presentation was 51 years; 63% were men. Median survival was 165 months. With the exception of fingernail clubbing (P = .03) and extravascular volume overload (P = .04), no presenting feature, including the number of presenting features, was predictive of survival. Response to therapy (P < .001) was predictive of survival. Pulmonary hypertension, renal failure, thrombotic events, and congestive heart failure were observed and appear to be part of the syndrome. In 18 patients (18%), new disease manifestations developed over time. More than 50% of patients had a response to radiation, and 22% to 50% had responses to prednisone and a combination of melphalan and prednisone, respectively. We conclude that the median survival of patients with POEMS syndrome is 165 months, independent of the number of syndrome features, bone lesions, or plasma cells at diagnosis. Additional features of the syndrome often develop, but the complications of classic multiple myeloma rarely develop.

Angiogenesis plays an important role in the biology of multiple myeloma (MM) and has prognostic importance in this disease. Solitary plasmacytoma is a localized plasma cell malignancy that progresses to MM in a significant number of patients. We examined if angiogenesis is increased in solitary plasmacytoma and if it can help identify patients likely to progress to myeloma. We studied angiogenesis in plasmacytoma biopsy samples and bone marrow biopsies from 25 patients. High-grade angiogenesis was present in 64% of plasmacytomas. In contrast, bone marrow angiogenesis was low in all patients. Patients with high-grade angiogenesis in the plasmacytoma sample were more likely to progress to myeloma and had a shorter progression-free survival compared with patients with low-grade angiogenesis (P = .02). Angiogenesis is increased in solitary plasmacytoma and is a significant predictor of progression to myeloma and provides further evidence of its importance in the pathogenesis of myeloma.

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.

The t(11;14)(q13;q32) results in up-regulation of cyclin D1 and is the most common translocation detected in multiple myeloma, where it is also associated with a lymphoplasmacytic morphology. We performed an interphase fluorescent in situ hybridization (FISH) study to determine the clinical and biologic significance of the abnormality when testing a large cohort of myeloma patients. Bone marrow slides from multiple myeloma patients entered into the Eastern Cooperative Oncology Group phase III clinical trial E9486 and associated laboratory correlative study E9487 were analyzed using interphase FISH combined with immune-fluorescent (cytoplasmic immunoglobulin–FISH) detection of clonal plasma cells. We used FISH probes that hybridize to the 14q32 and 11q13 chromosomal loci. The t(11;14)(q13;q32) was correlated with known biologic and prognostic factors. Of 336 evaluable patients, 53 (16%) had abnormal FISH patterns compatible with the t(11;14)(q13;q32). These patients appeared to be more likely to have a serum monoclonal protein of less than 10 g/L (1 g/dL) (28% vs 15%, P = .029) and a lower plasma cell labeling index (P = .09). More strikingly, patients were less likely to be hyperdiploid by DNA content analysis (n = 251, 14% vs 62%, P &lt; .001). Patients with the t(11;14)(q13;q32) appeared to have better survival and response to treatment, although this did not reach statistical significance. Multiple myeloma with the t(11;14)(q13;q32) is a unique subset of patients, not only characterized by cyclin D1 up-regulation and a lymphoplasmacytic morphology, but is also more frequently associated with small serum monoclonal proteins and is much less likely to be hyperdiploid. These patients do not have a worsened prognosis as previously thought.

Lymphoplasmacytic lymphoma (LPL) is characterized by t(9;14)(p13;q32) in 50% of patients who lack paraproteinemia. Waldenström macroglobulinemia (WM), which has an immunoglobulin M (IgM) paraproteinemia, is classified as an LPL. Rare reports have suggested that WM sometimes is associated with 14q23 translocations, deletions of 6q, and t(11;18)(q21;q21). We tested for these abnormalities in the clonal cells of WM patients. We selected patients with clinicopathologic diagnosis of WM (all had IgM levels greater than 1.5 g/dL). Southern blot assay was used to detect legitimate and illegitimate IgH switch rearrangements. In addition to conventional cytogenetic (CC) and multicolor metaphase fluorescence in situ hybridization (M-FISH) analyses, we used interphase FISH to screen for t(9;14)(p13;q32) and other IgH translocations, t(11;18)(q21;q21), and 6q21 deletions. Genomic stability was also assessed using chromosome enumeration probes for chromosomes 7, 9, 11, 12, 15, and 17 in 15 patients. There was no evidence of either legitimate or illegitimate IgH rearrangements by Southern blot assay (n = 12). CC (n = 37), M-FISH (n = 5), and interphase FISH (n = 42) failed to identify IgH or t(11;18) translocations. Although tumor cells from most patients were diploid for the chromosomes studied, deletions of 6q21 were observed in 42% of patients. In contrast to LPL tumors that are not associated with paraproteinemia and that have frequent t(9;14)(p13;q32) translocations, IgH translocations are not found in WM, a form of LPL tumor distinguished by IgM paraproteinemia. However, WM tumor cells, which appear to be diploid or near diploid, often have deletions of 6q21.

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).