Results of upfront therapy for marginal zone lymphoma (MZL).

Abstract

e19510 Background: MZL is an indolent NHL composed of 3 subtypes: extranodal (MALT), splenic marginal zone (SMZL) and nodal marginal zone (NML). While MALT usually presents with early stage, the others frequently present with advanced disease. Early stage MALT is usually treated with XRT or antibiotics with ~85-90% failure free survival (FFS) and overall survival (OS), while for SMZL watch and wait or splenectomy (Spl) have been the mainstay of therapy. Spl leads to improvement but rarely to CR. 5 yr FFS and OS with Spl have been 45% and 80%. At 10 yrs FFS and OS are 22% and 62%. NML is usually managed with watch and wait. The 5 yr FFS and OS for NML have been 30% and 60%. Watch and wait and Spl are used in part because advanced MZL is considered incurable. Rituximab (R) as well fludarabine (F) are active in this disorder but traditionally are given after relapse. Methods: Instead of watch and wait or Spl, we have used upfront chemo with curative intent for SMZL and NML as well as for advanced MALT. For early stage MALT we used either XRT alone or antibiotics. We hereby report on 44 pts with MZL of which 31 were MALT, 9 SMZL, 4 NMZL. For the purpose of analysis we divided the pts in 2 groups. Group 1 consists of 22 early stage MALT who were all treated with either XRT (N=17) or antibiotics +/- surgery (N=5). Group 2 consists of 22 cases who were treated with chemo alone. This group is made up of 9 MALT (4 advanced stage, 3 early stage but with transformation, 2 early stage but in whom XRT was contraindicated), 9 advanced stage SMZL, 4 NML. Chemo for group 2 consisted of F, mitoxantrone, dexamethasone, rituximab (FND-R) (N=14) or R-CHOP (N=8). Maintenance R was used in 70% of group 2. Results: Of the whole group, 100% were CR and only 2 relapsed at 70 and 75 months; both relapses were stage I MALT and had received XRT only. Both were salvaged with FND-R and remain NED 27 and 39 months from relapse. At 10 yrs, FFS was 80% and OS=100%. None of the 22 in group 2 have relapsed. The long-term toxicity has been acceptable. Conclusions: The excellent FFS and OS using upfront chemotherapy in group 2, suggests that this disorder is curable and our results should be confirmed in a prospective trial. For those with early stage MALT, XRT alone +/- antibiotics and when necessary salvage with FND-R, should be tested.