Anton Hagenbeek

PURPOSE: Standardized response criteria are needed to interpret and compare clinical trials and for approval of new therapeutic agents by regulatory agencies. METHODS: The International Working Group response criteria (Cheson et al, J Clin Oncol 17:1244, 1999) were widely adopted, but required reassessment because of identified limitations and the increased use of [18F]fluorodeoxyglucose-positron emission tomography (PET), immunohistochemistry (IHC), and flow cytometry. The International Harmonization Project was convened to provide updated recommendations. RESULTS: New guidelines are presented incorporating PET, IHC, and flow cytometry for definitions of response in non-Hodgkin's and Hodgkin's lymphoma. Standardized definitions of end points are provided. CONCLUSION: We hope that these guidelines will be adopted widely by study groups, pharmaceutical and biotechnology companies, and regulatory agencies to facilitate the development of new and more effective therapies to improve the outcome of patients with lymphoma.

Standardized guidelines for response assessment are needed to ensure comparability among clinical trials in non-Hodgkin's lymphomas (NHL). To achieve this, two meetings were convened among United States and international lymphoma experts representing medical hematology/oncology, radiology, radiation oncology, and pathology to review currently used response definitions and to develop a uniform set of criteria for assessing response in clinical trials. The criteria that were developed include anatomic definitions of response, with normal lymph node size after treatment of 1.5 cm in the longest transverse diameter by computer-assisted tomography scan. A designation of complete response/unconfirmed was adopted to include patients with a greater than 75% reduction in tumor size after therapy but with a residual mass, to include patients-especially those with large-cell NHL-who may not have residual disease. Single-photon emission computed tomography gallium scans are encouraged as a valuable adjunct to assessment of patients with large-cell NHL, but such scans require appropriate expertise. Flow cytometric, cytogenetic, and molecular studies are not currently included in response definitions. Response rates may be the most important objective in phase II trials where the activity of a new agent is important and may provide support for approval by regulatory agencies. However, the goals of most phase III trials are to identify therapies that will prolong the progression-free survival, if not the overall survival, of the treated patients. We hope that these guidelines will serve to improve communication among investigators and comparability among clinical trials until clinically relevant laboratory and imaging studies are identified and become more widely available.

BACKGROUND: High-dose chemotherapy followed by autologous bone marrow transplantation is a therapeutic option for patients with chemotherapy-sensitive non-Hodgkin's lymphoma who have relapses. In this report we describe a prospective randomized study of such treatment. METHOD: A total of 215 patients with relapses of non-Hodgkin's lymphoma were treated between July 1987 and June 1994. All patients received two courses of conventional chemotherapy. The 109 patients who had a response to chemotherapy were randomly assigned to receive four courses of chemotherapy plus radiotherapy (54 patients) or radiotherapy plus intensive chemotherapy and autologous bone marrow transplantation (55 patients). RESULTS: The overall rate of response to conventional chemotherapy was 58 percent; among patients with relapses after chemotherapy, the response rate was 64 percent, and among those with relapses during chemotherapy, the response rate was 21 percent. There were three deaths from toxic effects among the patients in the transplantation group, and none among those in the group receiving chemotherapy without transplantation. The two groups did not differ in terms of prognostic factors. The median follow-up time was 63 months. The response rate was 84 percent after bone marrow transplantation and 44 percent after chemotherapy without transplantation. At five years, the rate of event-free survival was 46 percent in the transplantation group and 12 percent in the group receiving chemotherapy without transplantation (P = 0.001), and the rate of overall survival was 53 and 32 percent, respectively (P = 0.038). CONCLUSIONS: As compared with conventional chemotherapy, treatment with high-dose chemotherapy and autologous bone marrow transplantation increases event-free and overall survival in patients with chemotherapy-sensitive non-Hodgkin's lymphoma in relapse.

The prognosis of follicular lymphomas (FL) is heterogeneous and numerous treatments may be proposed. A validated prognostic index (PI) would help in evaluating and choosing these treatments. Characteristics at diagnosis were collected from 4167 patients with FL diagnosed between 1985 and 1992. Univariate and multivariate analyses were used to propose a PI. This index was then tested on 919 patients. Five adverse prognostic factors were selected: age (> 60 years vs < or = 60 years), Ann Arbor stage (III-IV vs I-II), hemoglobin level (< 120 g/L vs > or = 120 g/L), number of nodal areas (> 4 vs < or = 4), and serum LDH level (above normal vs normal or below). Three risk groups were defined: low risk (0-1 adverse factor, 36% of patients), intermediate risk (2 factors, 37% of patients, hazard ratio [HR] of 2.3), and poor risk (> or = 3 adverse factors, 27% of patients, HR = 4.3). This Follicular Lymphoma International Prognostic Index (FLIPI) appeared more discriminant than the International Prognostic Index proposed for aggressive non-Hodgkin lymphomas. Results were very similar in the confirmation group. The FLIPI may be used for improving treatment choices, comparing clinical trials, and designing studies to evaluate new treatments.