Haacke EA, et al. - The purpose of this study is to evaluate whether the presence of germinal centres (GCs) is increased in labial gland biopsies from patients with primary Sjogren's syndrome (pSS) who developed parotid mucosa-related lymphoid tissue (MALT) lymphoma, the dominant NHL-subtype in pSS, compared with patients with pSS who did not develop lymphoma. Presence of GCs in labial gland biopsies does not differ between patients with pSS that develop parotid MALT lymphoma and patients with pSS who do not develop lymphoma. The presence of GCs in labial gland biopsies is therefore not a predictive factor for pSS-associated parotid MALT lymphomas.