Although the minor salivary gland biopsy (MSGB) is a major criterion for the diagnosis of Sjögren syndrome (SS), multiple studies have outlined difficulties in standardization. The purpose of this study was to answer the following question: in all patients referred for MSGB, did strict application of focus scoring criteria alter the sensitivity of and predictive value of the MSGB in the diagnosis of SS compared with the initial interpretation?
The authors designed a cross-sectional study of patients referred to the Massachusetts General Hospital Department of Oral and Maxillofacial Surgery (Boston, MA) over a 5-year period for MSGB. The primary predictor variable was the MSGB focus score. The primary outcome variable was the SS diagnosis. The newly established SS diagnosis status results were compared with the initial SS diagnoses. Sensitivity, specificity, and positive and negative predictive values (PPV and NPV) were calculated. Other relevant variables of interest, such as size of glandular tissue harvested and associated signs and symptoms, also were documented. The primary predictor variable was the MSGB focus score and the primary outcome variable was the SS diagnosis (positive or negative).
Seventy-three patients met the inclusion criteria. The mean age was 48.5 years (range, 19 to 71 yr) and 64 were women (87.6%). The authors' previous study using initial pathology reports yielded 80.0% sensitivity, 87.5% specificity, 57.1% PPV, and 95.5% NPV. The present review of the MSGB using strict focus scoring guidelines yielded 95.4% sensitivity, 76.4% specificity, 63.6% PPV, and 97.5% NPV.
The MSGB is an important major criterion in establishing a diagnosis of SS. Application of strict focus scoring guidelines when reviewing the MSGB yielded a sensitivity far greater than initially reported in this group. Difficulties with interpretation are discussed. Future studies will focus on improvement of interpretation and immunohistochemical aids in diagnosis.