Hyperdiploid myeloma cell as an indicator of poor prognosis and drug refractoriness

Outcomes of primary refractory multiple myeloma and the impact of novel therapies

Over the past decade, use of novel agents, including immunomodulatory drugs (IMiDs) and proteasome inhibitors (PIs) has resulted in high response rates and improvement in overall survival (OS) for patients with multiple myeloma (MM); however, the prognostic significance of refractoriness to these agents when used as initial therapy has not been extensively studied. We reviewed the outcomes of 816 consecutive patients treated for MM at our institution since 2006 to evaluate the survival difference between those achieving at least a partial response (PR) to induction therapy and those who were primary refractory. The median OS from start of therapy was significantly shorter for the primary refractory group at 3.6 vs. 7.6 years for the responding patients (P < 0.001). The difference in median OS persisted when only patients receiving a novel agent as part of induction therapy were considered (3.6 vs. 7.9 years, P < 0.001) and in a 4-month landmark analysis (4.2 vs. 7.6 years, P < 0.001). The median OS for patients achieving a complete response (CR), very good partial response (VGPR), PR, or less than PR was not reached (NR), 6.1, 6.4, and 4.2 years from the 4-month landmark, respectively (P < 0.001). The comparatively poor outcomes of patients refractory to induction therapy in the current era of novel agents suggests that this high-risk subpopulation must be further studied for predictors of resistance and, when identified, should be targeted for clinical trials.

The flow-cytometric DNA content of the plasma cells of patients with multiple myeloma is a prognostic factor: a single institution experience

The flow-cytometric DNA content in the plasma cells of patients with multiple myeloma has been studied as a prognostic factor and contrasting results have been found. In a group of 45 patients with myeloma from a single institution, the DNA content of the malignant plasma cells was studied by means of flow cytometry: no patients were found to have hypodiploid DNA content, 14 patients had hyperdiploid DNA, and 31 patients were found to have diploid DNA. The overall survival of patients with hyperdiploid DNA was better than that of patients with diploid DNA: 93% at 85 months and 79% at 89 months, respectively; in both groups, the median overall survival has not been reached. No correlation was found between the DNA content and the International Staging System and the discriminatory effect of the DNA content was apparent only in the patients who were not autografted. It is concluded that the flow-cytometric DNA content of the plasma cells of patients with multiple myeloma may be a prognostic factor independent of others already identified and that myeloma patients with hyperdiploid DNA content in the plasma cells may have a better prognosis than those with a normal DNA content.

Flow cytometric analysis of lymphomas: current status and usefulness

CONTEXT

Immunophenotyping has become a routine practice in the diagnosis and classification of most cases of non-Hodgkin lymphoma, and flow cytometry is often the method of choice in many laboratories. The role that flow cytometry plays, however, extends beyond just diagnosis and classification.

OBJECTIVE

To review and evaluate the current roles of flow cytometry in non-Hodgkin lymphoma, to compare it with immunohistochemistry, and to discuss its potential future applications in the molecular diagnostic era.

DATA SOURCES

The information contained herein is derived from peer-reviewed articles on the subject published in the English-language medical literature during the years 1980 to 2005 that were identified using PubMed (http://www.ncbi.nlm.nih.gov/entrez/query.fcgi, 1980-2005) search, various books and other sources on flow cytometry, and the author's personal experience of more than 10 years with flow cytometric analysis of lymphomas and leukemia using Becton-Dickinson (San Jose, Calif) and Beckman-Coulter (Miami, Fla) flow cytometers.

STUDY SELECTION

Studies were selected based on adequate material and methods, statistically significant results, and adequate clinical follow-up.

DATA EXTRACTION

The data from various sources were compared when the methods used were the same or similar and appropriate controls were included. Most of the studies employed 2-color, 3-color, or 4-color flow cytometers with antibodies from Becton-Dickinson, Beckman-Coulter, or DakoCytomation (Carpinteria, Calif). Results were evaluated from studies utilizing the same or similar techniques and flow cytometers. Only objective data analyses from relevant and useful publications were included for reporting and discussion.

DATA SYNTHESIS

Flow cytometry serves a variety of roles in the field of lymphoma/leukemia including rapid diagnosis, proper classification, staging, minimal residual disease detection, central nervous system lymphoma detection, evaluation of prognostic markers, detection of target molecules for therapies, ploidy analysis of lymphoma cell DNA, and evaluation of multidrug-resistance markers. It offers many advantages in comparison to immunohistochemistry for the same roles and provides uses that are either not possible or not preferable by immunohistochemistry such as multiparameter evaluation of single cells and detection of clonality in T cells.

CONCLUSIONS

By virtue of its ability to evaluate not only surface but also cytoplasmic and nuclear antigens, flow cytometry continues to enjoy widespread use in various capacities in lymphoma evaluation and treatment. Additional roles for flow cytometry are likely to be invented in the future and should provide distinctive uses in the molecular era.

Chromosomal aberrations in 130 patients with multiple myeloma studied by interphase FISH: diagnostic and prognostic relevance

The study described the molecular cytogenetic characterization of myeloma cells in 130 patients via interphase fluorescence in situ hybridization. Nine repetitive DNA probes (for chromosomes 3, 7, 9, 11, 15, 17, 18, X, and Y) as well as seven single-copy DNA probes (for chromosomes 13, 17, 21, and two each for chromosomes 5 and 22) were used for the hybridizations. Using this panel of probes, we were able to show aberrations in 86% of patients. Most of them had one to three aberrations. There was a distinct correlation between the number of aberrations per patient and the tumor stage. Thus, the proportion of patients with 8-12 aberrations increased from 16% in stage II to 26% in stage III. There were marked differences among the chromosomes with respect to the prevalence of genomic losses and gains and deletions of gene loci. Chromosomes 3, 5, 7, 9, 11, 15, and 21 showed a preference for genomic gains. Losses were most often found for chromosomes 13 and 17 (locus specific) as well as for the X and Y chromosomes. The frequency of monosomies and trisomies were approximately the same for chromosomes 15 and 18, which indicates a skewed pattern of distribution. We found two specific aberrations that caused distinct changes in the survival rates of the patients: deletion 13q14 (28% of patients) and translocation of the IGH locus 14q32 (79% of 39 patients who were analyzed separately). The results obtained in this study yielded data of extremely relevant prognostic value.

Multidrug resistance-associated protein (MRP1) is overexpressed in DNA aneuploid carcinomatous cells in non-small cell lung cancer (NSCLC)

Resistance to chemotherapy is intrinsically present in most nonsmall-cell lung carcinomas (NSCLC). No parameter has yet been determined to predict the response to chemotherapy. However, MRP1 (multidrug resistance-associated protein) is suspected to play an important role in resistance to treatment. The genetic basis for this resistance is not clearly understood, but it could result from chromosome reassortments catalyzed by aneuploidy. The aim of this study was to investigate MRP1 expression concurrently to DNA ploidy analysis in order to evaluate the link between MRP1 expression and chromosome 16 (MRP1 gene location) aberrations in NSCLC before treatment. Eighty-four surgical tumor specimens, 18 selected samples containing more than 80% of carcinomatous cells and 11 samples from normal bronchial epithelium were studied. Samples were stained by MRP1 FITC indirect staining and propidium iodide and analyzed by Flow Cytometry. Fifty tumors contained at least 1 DNA-aneuploid clone and the percentage of MRP1-positive cells was higher in DNA-aneuploid cells (p = 0.0003). All tumors expressed MRP1, but the level of expression was 3-fold higher in DNA-aneuploid cells than in DNA-diploid cells (normal bronchial cells as well as carcinomatous cells) (p < 0.0001). FISH analysis of 24 tumor imprints using a chromosome 16 alpha-satellite centromere probe demonstrated significantly more frequent gain of chromosome 16 in DNA-aneuploid tumors. These results suggest that MRP1 overexpression in NSCLC could be a consequence of chromosome 16 reassortments catalyzed by aneuploidy and that DNA-aneuploid tumors could require different treatment modalities from those applied to DNA-diploid tumors.

Response to first-line chemotherapy and long-term survival in patients with multiple myeloma: results of the MM87 prospective randomised protocol

In this study we evaluated whether a good response to conventional chemotherapy, i.e. a significant tumour reduction, is a prerequisite for improved survival in multiple myeloma (MM). Between January 1987 and March 1990, 341 consecutive previously untreated patients with MM received chemotherapy within the prospective, multicentre, randomised Protocol MM87. Of these, 258 patients were evaluable for both response and long-term survival and 244 (94.6%) have died. The median survival of all patients was 40 months (6-162 months). The median survival did not differ between patients who had complete response (CR) (50 months (9-162 months)), partial response (PR) (46 months (8-147 months)) or stable disease (SD) (41 months (7-135 months)). The median survival was shorter (13.6 months (6-135 months)) (P<0.0001) in patients whose disease progressed while they were receiving first induction chemotherapy. Causes of death were more frequently (P=0.04) related to MM in patients who had progressive disease (PD) than in patients who had a CR or PR or SD. The main clinical and laboratory characteristics were similar in the four groups. These data indicate that patients who maintain SD during first-line chemotherapy have a prognosis similar to that of patients who attain a response. Only patients whose disease progresses have a distinctly worse outcome.

The bone marrow plasma cell labeling index by flow cytometry

The bone marrow plasma cell labeling index is the most important prognostic indicator for patients with multiple myeloma. Traditionally, this test has been performed as a two color immunofluorescent microscope technique which is time consuming and requires a degree of subjectivity in its interpretation. We have assessed various adaptations of this method to flow cytometry. A bromodeoxyuridine method has been compared with a propidium iodide DNA method to detect cells in S phase and CD38-FITC has been compared with CD38-FITC + CD138-FITC and CD38-biotin + streptavidin FITC to identify plasma cells. The mean channel fluorescent intensity of the plasma cell peaks for each of these markers was 12. 7, 17.4 and 35.3 respectively demonstrating the superiority of CD38-biotin + streptavidin FITC. Analysis after propidium iodide staining provided a good correlation with the slide technique (r = 0. 71; P < 0.0001) but the bromodeoxyuridine method did not correlate with the slide method (r = 0.09; P = NS). The labeling index values obtained from either of the flow methods were greater than the microscopic method. Thus a labeling index of >4% will replace the traditional >1% threshold for identifying patients with a significantly increased labeling index. The advantages of the new method are that it takes less time to perform, is more objective and provides additional data on ploidy and cell cycle status.