Primary mediastinal large B-cell lymphoma with sclerosis: a clinical study of 89 patients treated with MACOP-B chemotherapy and radiation therapy.

BACKGROUND AND OBJECTIVES

Primary mediastinal large B-cell lymphoma (PMLBCL) with sclerosis has recently been recognized as a specific clinical and pathologic entity for which the best therapeutic approach seems to be a combination of chemotherapy and radiotherapy.

DESIGN AND METHODS

Between 1989 and 1998, 89 previously untreated patients with PMLBCL with sclerosis were treated with a combination of a third-generation chemotherapy regimen (MACOP-B) and mediastinal radiation therapy. The response evaluations were examined after chemotherapy and at the end of radiotherapy.

RESULTS

Twenty-three (26%) patients achieved a complete response (CR) and 59 (66%) obtained a partial response (PR) after the MACOP-B regimen. After radiation therapy, 55/59 (93%) of the patients in PR achieved CR. The CR rate at the end of the treatment was 88% (78/89). Only 7 (8%) patients were non-responders. Among the 78 patients who obtained a CR there were 7 (9%) relapses in a median follow-up of 5 months (all relapses occurred within 9 months); the other 71 patients are currently in continuous CR with a median follow-upof 45 months (range, 4-110 months). Projected overall survival was 86% at 9 years; the relapse-free survival curve of the 78 patients who achieved CR was 91% at 9 years.

INTERPRETATION AND CONCLUSIONS

In patients with PMLBCL with sclerosis, combined modality treatment using the MACOP-B chemotherapy regimen and radiation therapy induces a good remission rate with the patients having a greater than 90% chance of surviving disease-free at 9 years. Radiotherapy often plays a pivotal role in obtaining CR status.