Radiotherapy improves survival without increased cardiac death risk in gastric MALT

Patients with stage I gastric mucosa-associated lymphoid tissue (MALT) who underwent radiotherapy (RT) have better survival, with no risk increase in cardiac death, a recent study has shown. Those with gastric MALT show similar cardiac-specific survival (CSS) to those with orbital MALT.

A total of 2,996 patients were analysed (median follow-up, 5.6 years), of which 27.5 percent had received RT alone, 12.1 percent chemotherapy alone, 3.9 percent chemoradiotherapy, and 56.5 percent no/unknown treatment (including antibiotic therapy).

Patients who received chemotherapy alone had worse overall survival (OS; hazard ratio [HR], 1.67, 95 percent confidence interval [CI], 1.32–2.10; p<0.001) and MALT-specific survival (MSS; HR, 2.10, 95 percent CI, 1.36–3.23; p=0.001) compared to those who received RT alone.

Patients on chemotherapy also appeared to have worse CSS (HR, 1.56, 95 percent CI, 0.92–2.66; p=0.10), but this was not statistically significant. In addition, no significant difference in CSS (HR, 0.80, 95 percent CI, 0.49–1.31; p=0.38) was observed when comparing orbital and gastric MALT patients.

“Although we cannot analyse nonfatal cardiac toxicity, these results suggest that, absent antibiotic therapy, RT should remain first-line treatment for early-stage gastric MALT,” the authors said.

This study identified adult patients with MALT treated between 1993 and 2014. Using the Kaplan-Meier estimator and Cox proportional hazards analyses, they examined the association between treatment modality (eg, RT, chemotherapy, combination, and no treatment) and OS, MSS, non-MSS, and CSS.

“RT is an effective treatment for localized gastric MALT lymphomas unresponsive to antibiotic therapy,” the authors said. “[H]owever, irradiating the stomach can result in significant radiation to the heart, a risk factor for cardiac disease.”