Gordon, Dewald W.

Abstract Background: Multiple myeloma (MM) has been studied by conventional cytogenetics and fluorescence in situ hybridization using DNA probes (FISH) on interphase nuclei and metaphase cells, but the relative clinical significance of proliferating (metaphase) versus non-proliferating (interphase) cells at diagnosis is poorly understood. We investigated a consecutive series of 154 patients (pts) with newly diagnosed untreated MM, and compared results for metaphase and interphase cells with survival. Methods: Bone marrow within 30 days of diagnosis was analyzed by standard cytogenetics. Leftover cells were stored at −70°C. Interphase and metaphase FISH was done using probes for IGH, FGFR3, CCND1, c-MAF, D13S319, LAMP1, p53 and D17Z1 to detect t(4;14), t(11;14), t(14;16) and chromosome 13 or 17 anomalies, respectively. We analyzed <10 metaphases and 200 unselected interphase nuclei for each FISH probe set for each pt. Survival rates were estimated using Kaplan-Meier and differences in survival curves compared using log-rank test. Results: 61 (39.6%) pts had abnormal metaphases by cytogenetics (43 pts) and/or FISH (46 pts): 12 (19.7%) had t(11;14) by cytogenetics (3 pts) and/or FISH (11 pts), 11 (18.0%) had t(4;14) by FISH but not cytogenetics, and 3 (4.9%) had t(14;16) by FISH but not cytogenetics. Metaphases with 13q- were seen in 30 pts (49.2%). Interphase FISH results were abnormal for 133 (86.3%) pts: mean percent neoplastic nuclei was 26.9 ± 21.6 (3.9 to 99.0). Mean percent plasma cells was 54.7 ± 24.6 (3.0 to 99.0). Each of the 61 pts with abnormal metaphases was also abnormal in interphase nuclei. Median survival for pts with ≥50% (20 pts) abnormal nuclei was 202 days vs. 1351 days for pts with <50% (134 pts) (p<0.001). Median survival for pts with abnormal metaphases (61 pts) was 587 days vs. 1404 days for pts with normal metaphases (93 pts) (p=0.002). Median survival was 381 days for 30 pts with 13q- metaphases compared with 1404 days for 38 pts with normal metaphases and 13q- interphase nuclei (p<0.001). Metaphase and interphase analysis along with other potential risk factors (hemoglobin <10, serum calcium ≥11, serum creatinine ≥2, plasma cell labeling index and percent bone marrow plasma cells) were evaluated by multivariate analysis using a stepwise selection in a Cox proportional hazards model. Only the observation of 13q- in metaphases or ≥50% abnormal interphase nuclei were significant predictors of survival. Conclusions: Analysis of metaphases at diagnosis is important to detect proliferating disease which is a strong indicator of poor prognosis. Metaphase FISH is a necessary adjunct to conventional cytogenetics to detect cryptic t(4;14) and t(14;16), and accurately detect prognostic chromosome anomalies such as 13q-. Observing a 13q- in metaphase cells is a strong predictor of survival compared with observing 13q- in only interphase nuclei. At diagnosis, analysis of interphase nuclei is efficient, identifies an abnormal clone in 86% of pts and defines a subset of patients with ≥50% nuclei that have a poor prognosis. Since analysis of metaphases gives better prognostic information, interphase FISH is not a substitution in the cytogenetic work up of patients with MM.

Abstract Background : Thirty to 50% of patients with myelofibrosis with myeloid metaplasia display detectable bone marrow cytogenetic abnormalities at diagnosis with some(Demory et al. Blood1988;72:855, Dupriez et al. Blood1996;88:1013, Reilly et al. BJH1997;98:96) but not other studies (Cervantes et al. BJH1998;102:684, Okamura et al. Int J Hematol2001;73:194) suggesting a detrimental effect on survival. Methods : The current prospective study was conducted as a follow-up of the observations from an antecedent retrospective study that identified sole abnormalities of either 13q- or 20q- as ‘favorable’ to survival (Tefferi et al. BJH2001;113:763). All clinical and laboratory measurements, including bone marrow examination and karyotype analysis, were performed concurrently in consecutive cases of histologically confirmed MMM regardless of either duration of disease or presence of active therapy. Survival, leukemic transformation rate, and clinical progression were determined from the time of cytogenetic analysis. Results : Karyotypic analysis was successfully performed in a total of 88 patients (median age 61 years; 31 females) and the results were normal in 49 (56%) and abnormal in the remaining 39 patients with 9 (10%) displaying ‘favorable’, and 30 (34%) ‘other’ clonal abnormalities. At the time of study entry, 57 patients were not recieving any form of therapy, 18 were newly diagnosed, and the Dupriez prognostic score distributions were ‘0’ in 33 patients, ‘1’ in 35 and ‘2’ in 20 (Dupriez et al. Blood1996;88:1013). All patients were followed for a minimum of 3 years and a median of 42 months. The 3 cytogenetic categories were similar in age and gender distribution. Survival in the favorable cytogenetic group was similar to that of the normal group and significantly better than the group with other cytogenetic abnormalities (p=0.02). Figure Figure Similarly, no patient (0%) in the ‘favorable’ group transformed into acute leukemia while 6 of 30 (20%) in the ‘other’ and 5 of 49 (10%) in the normal groups did (p=0.21). In a Cox regression analysis, cytogenetic lesions other than the ‘favorable’ kind, hemoglobin below 10 g/dL, leukocytosis, hypercatabolic symptoms, increased blood blast %, blood CD 34 count above 100 x 106/L were individually associated with shortened survival. In a multivariate analysis, only hemoglobin level and leukocyte count retained their significance. Conclusion : Single chromosomal abnormalities of either 13q- or 20q- should be considered as ‘favorable’ cytogenetic lesions in MMM while other abnormalities are associated with an adverse prognosis. The current observation explains the discrepancy in the literature regarding the prognostic relevance of cytogenetic findings in MMM and warrants additional studies to determine the value of incorporating the specific information in prognostic scoring systems.