Because the outcome of patients with primary ovarian non-Hodgkin's lymphoma (NHL) is controversial, we retrospectively analyzed experience with adults seen at the University of Texas M. D. Anderson Cancer Center from 1974 to 1993. Patients were included if at least one ovary was pathologically involved, and if combination chemotherapy was used that must have included doxorubicin for intermediate grade histologies. We identified 15 patients who constituted 0.5% of all untreated NHL and 1.5% of untreated ovarian neoplasms that presented to our instutition during this time. One patient refused therapy, leaving 14 assessable for response. Nine patients had intermediate-grade, 5 had high-grade, and none had low-grade NHL. One ovary was involved in 4 patients, and both in 10, in 7 of whom additional sites were involved, including supradiaphragmatic nodes in 2. Four patients had AAS I and 10 had AAS IV. Favorable (0 or 1) and unfavorable (>1) IPI scores were seen in 5 and 9 patients, respectively. The complete remission rate for all patients was 64%, and 5-year survival and FFS for all assessable patients were 57 and 46%, respectively. We conclude that the complete remission rate and FFS of patients with ovarian NHL treated with appropriate chemotherapy appear to be similar to that of patients with other nodal NHLs. Further work is required to determine prognostic factors in ovarian NHL.