Ultrasound-guided core needle biopsy compared to open biopsy: a new diagnostic approach to major salivary gland enlargement in Sjögren’s syndrome

Objective Persistent (≥2 months) major salivary gland (SG) enlargement in primary Sjögren's syndrome (pSS) patients is a well-known sign of possible involvement by B-cell lymphoma. The study aimed to evaluate the diagnostic accuracy and safety of ultrasound-guided core needle biopsy (US-guided CNB) of major SGs in comparison to open surgical biopsy. Methods Prospective pSS patients (cases) with clinically persistent SG enlargement underwent US-guided CNB, and were compared to retrospective pSS patients (controls) submitted to open surgical biopsy. The features analyzed were pre-biopsy clinical and laboratory findings, biopsy-related complications (reported by the patient with a questionnaire and clinically verified), adequacy of the material for histology and diagnosis rendered. Results Thirteen cases underwent US-guided CNB: in 9/13 biopsy was performed on the parotid and in 4/13 on the submandibular gland. Sufficient material was obtained for pathological diagnosis in all samples. The final diagnoses were: 5/13 (38.5%) B-cell lymphoma, 1/13 (7.7%) lympho-epithelial sialadenitis, 4/13 (30.7%) other sialadenitis (granulomatous consistent with sarcoidosis, IgG4-related disease, chronic sclerosing, diffuse chronic) and 3/13 (23.1%) miscellaneous lesions. Thirteen controls underwent open surgical biopsy of the parotid, in one inadequate material was obtained, in 12 (92.3%) the pathologic diagnoses were: 4/12 (33.3%) B-cell lymphoma, 2/12 (16.7%) lympho-epithelial sialadenitis, 4/12 (33.3%) uncertain lymphoproliferative lesions, 2/12 (16.7%) miscellaneous lesions. 6/13 (46.1%) cases reported 6 transient complications, and 12/13 (92.3%) controls 2 persistent and 14 transient complications. Conclusion US-guided CNB represents a novel, clinically relevant and safe approach to the management of pSS patients with parotid or submandibular persistent enlargement.