A retrospective cohort study using the TriNetX database investigated the association between atopic dermatitis (AD), other type 2 inflammatory diseases (T2ID) and the risk of lymphoma, as well as the effect of treatment with dupilumab. Atopic dermatitis was associated with an increased risk of lymphoma in 801,508 cases and controls, including cutaneous T-cell lymphoma (CTCL) and non-Hodgkin's lymphoma (NHL). Non-dermatologic T2ID conferred an increased risk of lymphoma in 14.4 million cases and controls. In AD patients treated with dupilumab (n = 7,840 per group), exposure to dupilumab did not increase, but tended to decrease, the risk of lymphomas compared with other systemic treatments. This association with reduced risk was most pronounced in non-dermatological T2ID (n = 16,908 per group), especially for NHL. Limitations include retrospective analysis, data quality, and possible misregistration of ICD-10 codes.