LAUSR

Supplemental Digital Content is Available in the Text. Background: Immunoglobulin G4-related disease (IgG4-RD) and immunoglobulin G4-related ophthalmic disease (IgG4-ROD) complicated with nonlymphoid malignancy (NL-malignancy) are rare. No exact relationship between IgG4-RD and NL-malignancies has been established yet, and there have been few reports of different types of IgG4-ROD and related malignancies. Methods: We retrospectively reviewed medical records of patients diagnosed with IgG4-RD and NL-malignancy, whichever occurred first, from January 2015 to March 2021. In addition, the literature on the relationship between IgG4-ROD and NL-malignancy was reviewed. Results: There were 115 patients diagnosed with IgG4-RD, and 10 patients were enrolled in the study with NL-malignancy. Three patients were diagnosed with IgG4-ROD. One patient reported a previous history of cancer, and the other 2 patients developed cancer at or after the diagnosis of IgG4-RD. The 3 patients' cancers were located in the lung, gastrointestinal tract, and thyroid. Conclusions: There may be potential malignancy occurrence during follow-up of IgG4-RD patients, especially among elderly patients. In addition, IgG4-RD could be a paraneoplastic syndrome at or before the diagnosis of malignancy.