Sonographic features of lymphoma of the major salivary glands diagnosed with ultrasound-guided core needle biopsy in Sjögren's syndrome.

Objectives To identify ultrasound (US) features of lymphomas (L) of major salivary glands (SGs) in primary Sjogren's syndrome (pSS) patients and to differentiate US pattern of L and non-L. Methods prospectively, from September 2019 to March 2021, 27 pSS-patients with clinical findings suspicious for L of the SGs underwent US evaluation followed by US-guided core-needle biopsy (CNB). For each patient, we assessed the OMERACT score, dichotomised (0/1 "lower", 2/3 "higher"), and we compared it between L-pSS and nonL-pSS groups. For focal lesions, echogenicity, inner appearance, shape, margins, presence of septa, vascularisation and posterior acoustic features were also assessed and compared between the two groups; we planned to consider as "suspicious" features more frequently associated with L. We expected to compare frequencies at which two or more "suspicious" features were simultaneously present between L-pSS and nonL-pSS. P Results L-pSS showed more inhomogeneous glandular pattern (100% vs. 69.2% higher OMERACT; p=0.0407). For focal lesions, the "suspicious" features identified were: OMERACT grade 3, very hypoechoic, homogenous, oval shape, well-defined margins, presence of septa, colour-Doppler vascularization, posterior acoustic enhancement. 6/8 and 7/8 simultaneous suspicious features were significantly higher among L-pSS patients, compared to nonL-pSS (88.9% vs. 28.6%, p=0.034 for 6/8 features; 77.8% vs. 14.3%, p=0.040 for 7/8 features). Conclusions L of the major SGs in pSS was always associated with OMERACT scores 2 or 3 and presented with diffuse or focal patterns. For focal lesions, the association of more "suspicious" features made the diagnosis of L increasingly more likely. This information can help to improve planning of US-guided CNB.