Objective To investigate the prognostic value of C-reactive protein/albumin ratio (CAR) in gastric mucosaassociated lymphoid tissue (MALT) lymphoma.

Methods The patients with gastric MALT lymphoma initially diagnosed in Zhongshan Hospital, Fudan University from January 2004 to June 2020 were included, and CAR values were calculated. These patients were divided into a low-CAR group (n=66) and a high-CAR group (n=27) according to the optimal CAR cut-off value obtained by X-tile software. The baseline indicators and survival states between the two groups were collected. The Cox regression analysis and Kaplan-Meier method were used to assess the prognostic significance of CAR in gastric MALT lymphoma.

Results The optimal cut-off value of CAR was 0.05. Compared with the low-CAR group (CAR < 0.05, n=66), the highCAR group (CAR ≥ 0.05, n=27) had more patients older than 70 years old, higher anemia rate, higher C-reactive protein and β2-microglobulin levels, and lower albumin level (P < 0.05). Multivariate Cox analysis showed that IgG was an independent predictive factor (HR=0.528, 95%CI 0.304-0.915, P=0.023). The median overall survival (OS) time was longer in the low-CAR group than that in the high-CAR group (172.8 months vs 112.7 months, P=0.020). There was no significant difference in OS among different MALT-IPI score groups; the OS of patients with CAR combined with MALT-IPI score 2 was significantly worsen than patients with score 0 or 1 (P < 0.05).

Conclusions The prognosis of patients in high CAR group was worsen. The CAR can be used as an indicator for predicting the prognosis of gastric MALT lymphoma.