The Non-Hodgkin Lymphoma Pathologic Classification Project. Long-term follow-up of 1153 patients with non-Hodgkin lymphomas.

STUDY OBJECTIVE: To document the long-term prognosis of patients with non-Hodgkin lymphoma treated between 1971 and 1975 and to determine how the prognosis varies by histologic subtype and stage. SETTING: Three cancer referral centers in the United States and one center in Italy. PATIENTS: A consecutive sample of 1153 previously untreated patients with non-Hodgkin lymphoma. At the time of analysis, 71% of the patients had died and the median follow-up for patients still alive was 11.2 years. MEASUREMENTS AND MAIN RESULTS: The 10-year survival proportions were 45% (CI, 40% to 50%); 26% (CI, 22% to 30%); and 23% (CI, 18% to 30%) for patients with low-, intermediate-, and high-grade lymphomas, respectively. Patients with intermediate- and high-grade lymphomas were curable, but this was not apparent for patients with advanced stage low-grade lymphomas. For the low-grade follicular small cleaved and follicular mixed lymphomas, the Ann Arbor staging system distinguished the prognosis of patients with stage I disease from those with more extensive involvement. For the diffuse large cell and immunoblastic lymphomas, the Ann Arbor staging system distinguished long-term prognosis for patients with stage I disease from patients with stage II disease and those with more disseminated involvement. CONCLUSIONS: The probability of long-term survival for unselected patients with non-Hodgkin lymphoma can be substantial. Long-term prognosis depends on the histologic subtype of the tumor and the extent of dissemination. The Working Formulation for non-Hodgkin lymphomas is a simple and useful nomenclature for selecting treatment and reporting results. The Ann Arbor staging system is a useful but imperfect prognostic indicator.