The aim of this study was to investigate comparatively the clinical characteristics and immunological indicators of immunoglobulin G4 (IgG4)-related dacryoadenitis and lacrimal lymphomas.

105 patients (172 eyes) with IgG4-related dacryoadenitis and 39 patients (46 eyes) with lacrimal lymphoma diagnosed by histopathologist in Beijing Tongren Eye Center, Beijing Tongren Hospital affiliated to Capital Medical University from June 2011 to June 2019 were enrolled. There were 57 males (78 eyes) and 87 females (140 eyes) with an average age of (55.3±13.6) years-old (ranged from 10 to 89 years-old). The gender, age, eye type, past medical history, clinical manifestations, imaging findings and immunological indicators were recorded and statistics. Age was expressed as ±s, and independent sample t testing was used for comparison. Gender, eye type, past medical history and clinical manifestations were expressed as cases and percentage, and compared using Chi-square test or Fisher′s exact probability method. Immunological indicators were expressed as median and upper and lower quartiles or ±s, and non-parametric rank sum test was used for comparison.

The gender rate (male/female) were 1∶2.75 and 2.9∶1, respectively in IgG4-related dacryoadenitis group and lacrimal lymphoma group. The majority of IgG4-related dacryoadenitis patients were female, while other was male; lacrimal lymphoma was more common in monocular than IgG4-related dacryoadenitis with significant difference (χ²=27.047, 25.486; P<0.05). In the IgG4-related dacryoadenitis group, 24 cases had preoperative glucocorticoid history, accouting for 22.9%; 3 cases with a history of surgery, accouting for 2.9%; 4 cases with asthma, accouting for 3.8%; 4 cases with lymphadenopathy, accouting for 3.8%; 27 cases with sinusitis, accouting for 25.7%; and 3 cases with immune system diseases, accouting for 2.9%. In lacrimal lymphoma group, they were 9 cases, 9 cases, 0, 0, 5 cases and 0, accouting for 23.1%, 23.1%, 0, 0, 12.8%, 0, respectively. The difference between groups in the history of previous surgery was significant using Fisher′s exact probability test (P<0.05). There was no significant difference between groups in preoperative glucocorticoid history and sinusitis (χ²=0.001, 2.735; P>0.05). There were no significant differences in the history of asthma, lymphadenopathy and immune system diseases using Fisher′s exact probability test (P>0.05). The main clinical manifestations of two groups were eyelid swelling. There were 96 cases and 20 cases with eyelid swelling, accouting for 91.4% and 51.3%, respectively in IgG4-related dacryoadenitis group and lacrimal lymphoma group. There was a significant difference in the number of cases of eyelid swelling between two groups (χ²=29.261, P<0.05). The main manifestations through imaging device were lacrimal gland enlargement in both groups. There were 105 cases and 9 cases with eyelid swelling, accouting for 100.0% and 23.1%, respectively in IgG4-related dacryoadenitis group and lacrimal lymphoma group. There was a significant difference in the number of cases of eyelid swelling between two groups (χ²=102.024, P<0.05). The contents of complement 3 (C3), complement 4 (C4), rheumatoid factor (RF), immunoglobulin A (IgA), immunoglobulin M (IgM), C-reactive protein (CRP), anti-streptococcus hemolysin O (ASO), IgG, IgG1, IgG2, IgG3 and IgG4 in IgG4-related dacryoadenitis were 1002.00 (857.00, 1165.45) mg/dl, 204.50 (151.85, 242.73) mg/dl, 7.30 (2.62, 12.93)mg/dl, 48.50 (25.90, 82.35) mg/dl, 1.35 (0.61, 2.56) mg/dl, 2.01 (1.49, 2.78) mg/dl, 0.94 (0.64, 1.31) mg/dl, 1480.00 (1270.00, 1790.00) mg/dl, 674.00 (530.00, 830.50) mg/dl, 534.00 (428.50, 679.00) mg/dl, 53.50 (26.70, 78.35)mg/dl, 155.00 (122.00, 248.00) mg/dl, respectively. There were no significant differences in C3, C4, RF, ASO, CRP, IgA, IgG1 and IgG3 between two groups (Z=-0.040, -1.818, -0.144, -0.620, -0.699, -0.031, -1.731, -0.344; P>0.05). The differences of two groups in IgM, IgG, IgG2 and IgG4 were significant (Z=-3.932, -4.473, -2.821, -5.995; P<0.05).

The clinical features and laboratory indicators of lacrimal lymphoma are different from IgG4-related dacryoadenitis, and IgM, IgG, IgG2 and IgG4 may be the serological indicators for clinical differentiation between them.