Labial Salivary Gland Biopsy
Last updated: October 9, 2014
Synonyms: Labial or lip biopsy, minor salivary gland biopsy.
Description: Incisional biopsy of minor salivary glands in the lower lip is useful in the evaluation of xerostomia and the diagnosis of Sjögren’s syndrome.
Method: Patients should suspend aspirin or NSAIDs intake 3 to 7 days before the procedure. This outpatient procedure is usually done by a surgeon using local anesthesia. The lower lip is everted, and normal mucosa is incised with a 2-cm horizontal incision. At least five minor salivary glands are removed and sent for histopathologic examination.
Complications: Complications include numbness in the lower lip (<1%), local bleeding, infection, and pain.
Abnormal Pathology: A diagnosis of Sjögren’s syndrome can be entertained if there is more than one focus of lymphocyte clusters (>50 round cells in >4 mm2 of glandular tissue), with acinar atrophy and hypertrophy of ductal epithelial and myoepithelial cells. The reliability of the biopsy is improved if normal-appearing acini are also seen adjacent to foci of inflammation. Myoepithelial islands may not be seen with minor salivary gland biopsies. Focal lymphocytic sialoadenitis is graded as a focus score, indicating the number of inflammatory foci seen. A focus score of >1 has a 95% specificity and 63% sensitivity for Sjögren’s syndrome. A focus score of >10 implies near confluent inflammation.
Confounding Factors: False-positive results may be seen with lichen planus or mucosal trauma.
Indications: The procedure is indicated when Sjögren’s syndrome is suspected, especially when the clinical presentation is incomplete or other tests are inconclusive or negative.
Contraindications: Coagulopathy, anticoagulant therapy, local infection, mouth ulcers, and sensitivity to lidocaine or epinephrine are contraindications.
Alternative Procedures: Noninvasive procedures include salivary flow rate, sialography, or salivary scintigraphy.
Cost: $80–200 (does not include hospital charges or consultation).
Comment: Positive labial salivary gland biopsy does not imply coexistent ocular inflammation. In patients with parotid swelling, biopsy of the parotid may be considered, especially if other diagnoses (e.g., parotid tumors) are suspected.
BIBLIOGRAPHY
Daniels TE. Labial salivary gland biopsy in Sjögren’s syndrome. Arthritis Rheum 1984;27:147–156. PMID: 6696772
