Work

Salvage Irradiation for Ocular Adnexal Mucosa Associated Lymphoid Tissue Lymphoma Refractory to Chlamydia psittaci Eradication

Year: 2025

Type: article

Abstract: Background . Prospective trials show that Chlamydia psittaci (Cp) eradication with doxycycline is followed by lymphoma regression in two-thirds of patients with ocular adnexal MALT lymphoma (OAMZL). Postponing orbit irradiation, a standard treatment for OAMZL, while waiting for the tumor response to antibiotic, could raise concern. Herein, we report safety and efficacy of salvage radiotherapy in patients with OAMZL relapsed after or refractory to Cp eradication. Methods . Patients with stage-IEA OAMZL diagnosed at our institution between 2005 and 2023 were evaluated for safety and efficacy of radiotherapy as salvage treatment after doxycycline. Inclusion criteria were: 1) first-line Cp -eradicating therapy with doxycycline; 2) lymphoma relapsed or progressed locally; 3) orbital irradiation as salvage treatment. Results . 28 patients (median age 66 years; range 37-92; 16 males) were assessable; all patients but two (relapsing after partial response) experienced progressive disease during or after doxycycline (median 9 months; IQR 4-40). Radiotherapy (30-36 Gy in 15-18 fractions) was well tolerated, with only 3 cases of grade-2 cataract and 3 cases of grade-1 blepharitis; all irradiated patients achieved a lymphoma regression (ORR=100%), with a complete response rate of 89% (95%CI= 80-97). At a median follow-up of 60 months (range: 12-166) from radiotherapy, 8 patients experienced relapse, within the irradiated volume only in two (7%), with a 4-year PFS of 74% (95%CI=72-75). All patients but one are alive at a median follow-up from initial lymphoma diagnosis of 96 (IQR 47-128) months; 22 (79%) patients are disease-free. Conclusions . The postponing of orbit irradiation until relapse/progression after Cp -eradicating antibiotic therapy is a safe and effective strategy in patients with limited-stage OAMZL. The vast majority of OAMZL patients can be safely managed without chemotherapeutic agents, and radiotherapy can be delayed until relapse without affecting patients' survival.

Source: Advances in Radiation Oncology

DOI: 10.1016/j.adro.2025.101822