Nodular mixed lymphocytic-histiocytic lymphoma (NM): response and survival. Eastern Cooperative Oncology Group

Eighty patients with nodular mixed lymphocytic-histiocytic lymphoma (NM) entered on four different Eastern Cooperative Oncology Group chemotherapy studies were analyzed for response and survival. They were compared with 249 patients with nodular lymphocytic poorly differentiated lymphoma (NLPD), who were treated similarly. The response rates in NM were: CR 45%, PR 30%, NC-PD 25%. In NLPD the quality of response had little effect on survival (CR 91%, PR 90%, NC-PD 76%), whereas in NM the two year survivorship of 85% for CR dropped drastically to 33% for the partial responders (P less than 0.01). Ninety percent of the previously untreated NLPD, but only 59% of the comparable group of NM, survived 2 years. In 23 patients with NM in which the pattern was reported as both nodular and diffuse (ND-M), the 2-year survival of 35% was markedly inferior to a 66% 2-year survivorship observed in 57 patients with the pure nodular pattern (P less than 0.05). It appears that NM is a less favorable lymphoma type than NLPD. In NM achievement of a CR affects survival favorably; consequently, the use of aggressive chemotherapy regimens in an attempt to achieve high rates of CR are recommended. In NLPD, on the other hand, since survival curves of partial and complete responders are almost identical, suboptimal treatments may be justified.