Evaluation of argyrophilic nucleolar organiser regions (AgNORs) in multiple myeloma

Aim-To investigate the prognostic value of argyrophylic nucleolar organiser regions (AgNORs) in multiple myeloma. Methods-Bone marrow aspirates from 55 newly diagnosed patients with multipl e myeloma were stained with the one step AgNO3 technique. The mean number o f AgNORs in each plasma cell nucleus (AgNOR count) was tested for a possibl e correlation with other clinical and laboratory variables at presentation (clinical stage, substage, heavy and light chain isotype, haemoglobin conce ntration, platelet count, marrow infiltration rate, degree of skeletal lesi ons, M protein concentration, plasma cell morphology, and serum concentrati ons of calcium, albumin, lactate dehydrogenase, C reactive protein, and bet a(2) microglobulin) and with outcome (response to first line treatment, fir st remission duration, and overall survival). Results-A significant association between mean (SD) AgNOR count was found o nly for clinical stage (stage I, 3.09 (1.19); stage II, 3.80 (1.53); stage III, 5.28 (1.79); p < 0.005) and, from all stage determinants, only for M. protein concentration thigh, 5.92 (1.80); low, 4.01 (1.92); p < 0.001). The re was a linear relation between AgNOR count and serum M protein concentrat ion for patients with both IgG (r = 0.450; p < 0.01) and IgA (r = 0.768; p < 0.002) producing multiple myeloma. Conclusions-Unhke previous investigations, no clear prognostic value for th e AgNOR count was found in multiple myeloma. Instead, the results indicate that the AgNOR count might be an index for RI protein synthesis rate. This is consistent with other findings in tissues with low proliferative potenti al and high protein synthetic activity, and calls for a cautious interpreta tion of AgNORs in malignancies with similar features.