Primary Sjögren's syndrome (pSS) is a complex disabling systemic autoimmune disorder. The hallmark of pSS is the T-cell-mediated hyperactivation of B-cells, evolving from asymptomatic conditions to systemic complications and lymphoma development. On tissue level, the typical feature is the lymphocytic infiltration of the salivary gland by B-, T-and antigen presenting cells, as mirrored by the diagnostic cornerstone role of minor salivary gland (MSG) biopsy. B-cells show multiple possible roles in disease pathogenesis, from autoantibody production, to antigen presentation, and cytokine production. B-cells hyperactivation is supported by genetic risk factors, T-cell dependent and independent mechanisms, and the presence of different pathogenic B-cell subsets must be reminded. Many aspects have been investigated in the last year regarding genetic and epigenetics, B-and T-cell role in pSS pathogenesis, their interaction with salivary gland epithelial cells (SGECs) and in their direct or indirect use as biomarkers and predictors of disease development, activity, and lymphomagenesis.In this review, following the others of this series, we will summarise the most recent literature on pSS pathogenesis and clinical features focusing in particular on new insights into pSS molecular stratification and therapeutic advances in the era of precision medicine.

Objective. To identify ultrasound (US) features of lymphomas (L) of major salivary glands (SGs) in primary Sjögren'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<0.05 were considered statistically significant. 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 vascularisation, posterior acoustic enhancement. 6/8 and 7/8 simultaneous suspicious features were significantly higher among 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 OMER-ACT 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.

Primary Sjögren’s syndrome (pSS) is a chronic and heterogeneous disorder characterized by a wide spectrum of glandular and extra-glandular features. The hallmark of pSS is considered to be the immune-mediated involvement of the exocrine glands and B-cell hyperactivation. This leads pSS patients to an increased risk of developing lymphoproliferative diseases, and persistent (>2 months) major salivary gland enlargement is a well-known clinical sign of possible involvement by B cell lymphoma. Better stratification of the patients may improve understanding of the mechanism underlying the risk of lymphoproliferative disorder. Here, we summarize the role of different imaging techniques and a bioptic approach in pSS patients, focusing mainly on the role of salivary gland ultrasonography (SGUS) and a US-guided core needle biopsy (Us-guided CNB) as diagnostic and prognostic tools in pSS patients with persistent parotid swelling.

Erosive lichen planus is an uncommon variant of lichen planus. We report a case of longstanding and refractory plantar ELPs causing disabling and opiate-resistant pain treated with 'classic' meshed skin graft combined with Rigenera V R micrografts. After approximately 9 months followup, no clinical recurrence or pain were observed. Erosive lichen planus (ELP) is an uncommon variant of lichen planus, involving oral cavity and genitalia and, less often plantar areas, where it usually presents with chronic erosions of the soles, along with intense, disabling pain and progressive loss of toenails. An abnormal immune cellular response (CD8þ lymphocytes and macrophages) and the consequent altered production of multiple mediators (interleukin-12, interferon-c, tumor necrosis factor-a, RANTES and MMP-9), seem to play a crucial role in the pathogenesis, although the etiology remains uncertain. From a histological point of view, ELP shows keratinocyte apoptosis, intense inflammatory response and basal epithelial keratinocytes TNF-a overexpression. Several therapies have been proposed, with variable and controversial results. While topical corticosteroids and topical calcineurin inhibitors are the treatments of choice for localized forms, short pulses of systemic glucocorticoids, phototherapy, and systemic immunosuppressants are recommended for generalized cases. Surgery has been reported as a possible therapeutic option in refractory and stable cases with localized lesions, either alone or with cyclosporine. Herein, we report a case of longstanding and refractory plantar ELPS causing disabling and opiate-resistant pain treated with 'classic' meshed skin graft combined with RigeneraV R micrografts.