Citations

AbstractThe immunoglobulin free light chain (FLC) is the precursor protein of amyloid in primary systemic amyloidosis (AL). Historically, the ability to monitor the amyloid protein precursor protein has been crude. We evaluated the utility of the FLC assay in a retrospective analysis of patients with AL undergoing peripheral blood stem cell transplantation (PBSCT). Ninety-three such patients had serial FLC measurements performed. The prognostic effects of the initial concentration and the extent of reduction of monoclonal FLC on survival were studied. There was a significantly higher risk of death in patients with higher baseline FLC (hazard ratio 2.6, P < .04). Baseline FLC correlated with serum cardiac troponin levels, and higher FLC levels were associated with more organs involved by amyloid, suggesting that high FLC levels may be associated with more advanced disease. The percent FLC reduction did not predict for survival, but the absolute level of FLC achieved after therapy did. Normalization of FLC level after PBSCT predicted for both organ response and complete hematologic response. Achievement of FLC response was a better predictor of survival than achievement of complete hematologic response or normalization of the FLC ratio. FLC measurements both before and after PBSCT are important predictors of patient outcome.

The mechanisms underlying aneuploidy in multiple myeloma (MM) are unclear. Centrosome amplification has been implicated as the cause of chromosomal instability in a variety of tumors and is a potential mechanism causing aneuploidy in MM. Using immunofluorescent (IF) staining, centrosome amplification was detected in 67% of monoclonal gammopathies, including monoclonal gammopathy of undetermined significance (MGUS). We also investigated the gene expression of centrosome proteins. Overall, gene expression data correlated well with IF-detected centrosome amplification, allowing us to derive a gene expression-based centrosome index (CI) as a surrogate for centrosome amplification. Clinically, MM patients with high CI (> 4) are associated with poor prognostic genetic and clinical subtypes (chromosome 13 deletion, t(4; 14), t(14;16), and PCLI > 1%, P < .05) and are shown here to have short survival (11.1 months versus 39.1 months, P < .001). On multivariate regression, a high CI is an independent prognostic factor. Given that centrosome amplification is already observed in MGUS and probably integral to early chromosomal instability and myeloma genesis, and patients with more extensive centrosome amplification have shorter survival, the mechanisms leading to centrosome amplification should be investigated because these may offer new avenues for therapeutic intervention.

Purpose To answer the question, “should elderly non–small-cell lung cancer patients be offered elderly-specific trials?” Patients and Methods The North Central Cancer Treatment Group (NCCTG) performed a pooled analysis of elderly patients who participated in elderly-specific trials (required age ≥ 65 years) and age-unspecified trials (required age ≥ 18 years). Between 1998 and 2000, all NCCTG non–small-cell lung cancer (NSCLC) patients with incurable cancer, age ≥ 65 years, and receiving first-line chemotherapy were included. A total of 118 elderly patients participated in elderly-specific trials, and 108, in age-unspecified trials. Demographics and outcomes were compared based on trial type. Results The median age of elderly patients in elderly-specific trials was greater: median (range): 73 years (65 to 87) and 70 years (65 to 85), respectively (P < .001), as was the percentage older than 80 years: 17% and 3%, respectively (P = .0008). Median survival times were 232 and 302 days, respectively (P = .08). After adjustment for baseline age, Eastern Cooperative Oncology Group performance score, cancer stage, and body mass index, this survival difference was not statistically significant (hazard ratio = 1.25; P = .16). Grade 3 or worse nonhematologic adverse event rates were greater in age-unspecified trials (81% v 57%, respectively; P < .001), as were grade 3 or worse hematologic events (68% v 10%, respectively; P < .001). Conclusion Elderly patients in NSCLC elderly-specific trials suffered lower rates of severe adverse events with no statistically significant differences in survival. It seems that elderly-specific trials are providing quality care and helping to define optimal cancer therapy in the elderly, particularly among the “oldest of the old.”

AbstractWaldenström macroglobulinemia (WM) is a serious and frequently fatal B-cell malignancy associated with an elevated monoclonal IgM protein in the serum. Many of the mechanisms leading to this disease are not yet known. B-lymphocyte stimulator (BLyS) is a TNF family member that is critical for maintenance of normal B-cell development and homeostasis. BLyS is overexpressed in a variety of B-cell malignancies and has been shown to inhibit apoptosis in malignant B cells. It also regulates immunoglobulin secretion by normal B cells. To determine the relevance of BLyS in WM, we examined the role of BLyS in WM patient samples. Malignant B cells were found to bind soluble BLyS and variably express the receptors BAFF-R, TACI, and BCMA. We also found expression of BLyS in bone marrow specimens by immunohistochemistry and elevated serum BLyS levels in patients with WM. BLyS, alone or in combination with cytokines that induce immunoglobulin production, was found to increase IgM secretion by malignant B cells. Furthermore, BLyS was found to increase the viability and proliferation of malignant B cells from WM patients. Due to the role of BLyS in WM, strategies to inhibit BLyS may potentially have therapeutic efficacy in these patients.