Oncological outcome and recurrence pattern analysis after involved-field irradiation in combination with rituximab for early-stage nodal and extranodal follicular lymphoma.

Abstract

PURPOSE:

Combined radioimmunotherapy (RIT) in follicular lymphomas (FL) has shown promising treatment efficacy in the Mabthera® and Involved field Radiation (MIR) study. Aim of this study was to analyze treatment efficacy and recurrence patterns after RIT in early-stage nodal and extranodal FL.

METHODS:

We reviewed 107 patients who were treated with combined RIT in two centers. Treatment consisted of 4 × rituximab followed by RIT with 4 × rituximab and involved field (IF) radiotherapy with 30/40 Gy. Median follow-up period was 71 months. In contrast to the MIR study, extranodal involvement and grade 3A histology were included in the analysis.

RESULTS:

Extranodal involvement and grade 3A histology were present in 21.8% and 13.1%, respectively. Overall response rate (ORR) after 4 × rituximab, after completion of RIT, and after 6 months was 78.1%, 98.8%, and 98.8%, respectively, with increasing rates of complete remissions (CR). Predictive factors associated with superior PFS were tumor size, completely excised lymphomas, and response to first 4 × rituximab. 5‑year PFS rate was 87.3%, with mostly outfield recurrences (94.1%). Second-line treatment was effective, with 53.3% CR and 46.7% partial remissions (PR). 5‑year OS was 98.1%. RIT was tolerated well, with mainly grade 1-2 acute side effects.

CONCLUSION:

The real-world efficacy of RIT is comparable with the results of the MIR study. Additionally, this analysis shows that extranodal involvement and grade 3A histology are not associated with inferior PFS.

• Authors: Laila König, Klaus Herfarth, Juliane Hörner-Rieber, Sascha Dietrich, Thomas Wiegel, Jürgen Debus, Andreas Viardot
• Journal: Strahlentherapie und Onkologie : Organ der Deutschen Rontgengesellschaft ... [et al] (Strahlenther Onkol) Vol. 196 Issue 8 Pg. 705-714 (Aug 2020) ISSN: 1439-099X [Electronic] Germany
• PMID: 32377821 (Publication Type: Journal Article, Multicenter Study)

Chemical References

• Antineoplastic Agents, Immunological
• Rituximab

Topics

• Adult
• Aged
• Aged, 80 and over
• Antineoplastic Agents, Immunological (administration & dosage, adverse effects, therapeutic use)
• Combined Modality Therapy
• Extranodal Extension (drug therapy, radiotherapy)
• Female
• Follow-Up Studies
• Humans
• Kaplan-Meier Estimate
• Lymphatic Irradiation (adverse effects)
• Lymphoma, Follicular (drug therapy, radiotherapy, surgery)
• Male
• Middle Aged
• Progression-Free Survival
• Remission Induction
• Retrospective Studies
• Rituximab (administration & dosage, adverse effects, therapeutic use)
• Salvage Therapy
• Treatment Outcome
• Young Adult