Fifty patients with intermediate- or high-grade non-Hodgkin's lymphoma who had relapsed following a complete remission (CR) induced by a doxorubicin-containing chemotherapy regimen participated in the PARMA pilot study. The patients ranged in age from 16 to 60 years (median age, 42). All patients received DHAP (dexamethasone/high-dose cytarabine/cisplatin) for two courses at 3- to 4-week intervals. Patients achieving a partial response (PR) or CR were scheduled to receive involved-field radiotherapy and high-dose BEAC (carmustine/etoposide/cytarabine/cyclophosphamide) followed by autologous bone marrow transplantation (ABMT). Of 48 evaluable DHAP-treated patients (one patient was lost to follow-up and one had no measurable disease), seven achieved CR, 21 PR, and 20 patients had no response or progressive disease. One responder died from treatment-related toxicity, and six others declined ABMT. The patient with no measurable disease did not progress on DHAP and received ABMT. In all, 22 patients underwent ABMT (20 with BEAC and two with cyclophosphamide plus total body irradiation); two patients (9%) died from toxicity and ten (45%) relapsed. One patient in continuous CR committed suicide 28 months post-ABMT, and nine are alive and disease-free 24 to 32 months (median, 30) post-ABMT. The actuarial 2-year event-free survival for patients undergoing transplantation is 40%. This prospective multicenter trial documented the ability of DHAP followed by ABMT to produce durable CR in a significant proportion of patients with relapsed aggressive non-Hodgkin's lymphoma (NHL). Forty-four percent of all study patients with relapsed lymphoma actually underwent ABMT, and 20% of the total group are projected to be long-term disease-free survivors.(ABSTRACT TRUNCATED AT 250 WORDS)