34 patients with the diagnosis of diffuse well-differentiated lymphocytic lymphoma (DLWD), confirmed by a Pathology Panel, who were entered on a previously reported Eastern Cooperative Oncology Group study (EST 1472), were analyzed for response and survival. The response rates were as follows: CR 32%, PR 39%, NC or PD 29%. Survival analysis according to chemotherapy response revealed an estimated two-year survivorship of CR 89%, PR 65%, NC 69%, and PD 44%. Comparison with NLPD entered on the same study showed a two-year survival of 83% for NLPD and 67% for DLWD, indicating significantly poorer survival for DLWD as compared to NLPD (p less than .05). Median survival for DLWD from diagnosis was 39.0 + months. The presence of lymphocytosis over 4000/mm3 had little effect on response rates or survival. We conclude that DLWD is a less favorable lymphoma type than NLPD and should be treated with aggressive chemotherapy since achievement of CR seems to effect survival favorably.