Assessment of bone marrow involvement by malignant plasma cells is an important element in the diagnosis and follow-up of patients with multiple myeloma and other plasma cell dyscrasias. patients with multiple myeloma. There was a notable discrepancy in bone marrow plasma cell percentages using the different methods of observation. In particular, there was a relatively poor concordance of Akebiasaponin PE manufacture plasma cell percentage estimation between aspirate smears and CD138 sections. Estimates of plasma cell percentage using CD138 sections exhibited the highest interobserver concordance. This observation was supported by computer-assisted image analysis. In addition, CD138 expression highlighted patterns of plasma cell infiltration indicative of neoplasia even in the absence of plasmacytosis. We conclude that examination of CD138 sections should be considered for routine use in the estimation of plasma cell weight in the bone marrow. = .0001) or HE sections (= .0001). Fig. 1 Scatter plots of interobserver results of bone marrow plasma cell percentage estimation using different methods of evaluation. Bone marrow plasma cell percentages obtained form aspirate smears (A) and HE sections (B) showed lower concordance than those … Table 1 Interobserver concordance for the different methods of plasma cell quantitation/estimation 3.2. Intraobserver concordance For both observers, as shown in Table 2 and Fig. 2, there was a poor intraobserver concordance in bone marrow plasma cell percentage results obtained by 3 different methods of evaluation, most notably Akebiasaponin PE manufacture between aspirate smears and CD138 sections (ICC = 0.55 for observer 1 and ICC = 0.47 for observer 2). Fig. 2 Scatter plots of intraobserver results of bone marrow plasma cell percentage estimation using different methods of evaluation. For both observers (1 and 2), there was a poor concordance in bone marrow plasma cell percentages, most notably between aspirate … Table 2 Intraobserver concordance between different methods of evaluation In most cases, as shown in Fig. 2, individual observers assessment of plasma cell percentage using different evaluation methods resulted in higher plasma cell percentage with CD138 sections than with aspirate smears or HE preparations (Fig. 2B, C, E, and F). However, in some cases, higher values of plasma cell percentage were recorded using aspirate smears or HE preparations. Overall, individual observers using different methods of evaluation recorded a high (>25%), and in some cases extreme, difference in plasma cell percentage in 30 of 79 cases, with the highest overall plasma cell percentage obtained by CD138 sections in 16 cases, by bone marrow aspirate smears in 8 cases, and by HE sections in 6 cases. 3.3. Bone marrow plasma cell quantitation by ACIS All montage images from 50 specimens were analyzed by a single pathologist using the ACIS software to provide an objective assessment of bone marrow plasma cell percentages. The number of regions selected for scoring ranged from 6 to 47 per case, and the analysis was Mouse monoclonal to Human Albumin accomplished in 15 to 30 minutes per case. The concordance between the plasma cell area percentage data derived from the semiautomated image analysis and the results of visual estimation of CD138 expression was higher, with an ICC = 0.90 for observer 1 and ICC = 0.92 for observer 2 (Fig. 3), than the concordance between CD138 sections and either the aspirate smears or the HE sections (Fig. 2). As shown in Fig. 3, with low-level involvement by plasma cells, the plasma cell area percentage obtained by the ACIS was higher than that recorded by visual estimation. Conversely, with very high levels of plasma Akebiasaponin PE manufacture cell involvement, the scores attained by ACIS tended to be lower than those obtained by visual estimation. Fig. 3 Scatter plots of results obtained with the ACIS-assisted analysis and visual estimation of CD138 sections (n = 50) for 2 observers (1 and 2). 3.4. Patterns of plasma cell distribution and cellular staining Based on the CD138 staining in the 79 cases with multiple myeloma included in the study, we recognized 4 unique morphologic patterns of plasma cell distribution, comparable to what was reported in previous studies using and light chain IHC [1]. These included interstitial patterns, micro-aggregates, large nodules, and diffuse patterns (Fig. 4ACD). Based on the dominant pattern of the plasma cell distribution, more than half (52%) of the cases experienced an interstitial pattern, 23% experienced microaggregates, 17% experienced Akebiasaponin PE manufacture large nodules, and 8% experienced diffuse infiltrates of plasma cell distribution. In 25% of cases, more than one pattern was present in the same section. In 12 cases (15%), CD138 highlighted microaggregates or isolated plasma cell nodules where the overall.