A follow-up study of minimally invasive lip biopsy in the diagnosis of Sjögren’s syndrome

The aims of this study were to characterize a minimally invasive technique of minor salivary gland biopsy of the lower lip and to present a large patient material undergoing this procedure because of a suspicion of Sjögren’s syndrome (SS), as well as to assess the procedure’s short-term and long-term value as a diagnostic test and a prognostic factor. The sample consists of consecutive 191 patients undergoing lower lip biopsy in 1987–1990 in Kanta-Hame Central Hospital, Hameenlinna, Finland. The method used was the retrospective chart review. Only three (1.6%) of the biopsies were uninformative, and only one (0.5%) of the patients had a biopsy complication. In 41% of the cases, biopsy was suggestive of SS. Females and elderly patients were more likely to have a positive biopsy result. Surprisingly, a large diversity between pathologists was observed. With the use of focus score instead of older Chisholm classification as an indicator of SS, the specificity of SS diagnostics improved, and the variability between pathologists diminished. Neither SS diagnosis nor positive lip biopsy for SS predicted patients’ long-term outcome. In only three patients (1.6%) did the histological diagnosis change due to repeated biopsies. The minimal invasive lower lip biopsy technique presented in this study is a reliable and safe aid in SS diagnostics. The currently recommended histological grading system (focus score ≥ 1 suggesting SS) is more specific and reproducible than older Chisholm classification. Repeated biopsy very rarely adds new information.