Transcutaneous Submandibular Gland Biopsy: A Diagnostic Test for Early Parkinsonís Disease
MJFF Research Grant, 2013
We have previously found that in autopsied patients with Parkinsonís disease (PD) the hallmark finding in the brain (Lewy-type alpha synuclein staining or LTS) is also found in the submandibular gland. We then performed transcutaneous biopsies of 15 living patients with PD (with less then five years of disease duration) and found that of the 12 biopsies with submandibular gland tissue that was identifiable, 9 (75%) showed LTS. This is close to the expected percentage of PD subjects that can be accurately identified by clinical examination only. The goal is to now determine whether this safe and well tolerated biopsy test will be positive in early PD patients, for whom early and accurate diagnosis is essential for clinical care, clinical trials, and research into the genetics, neuroimaging, and biomarkers for PD.
Twenty-five patients with PD, with disease duration of less than five year, and 10 healthy control subjects will be recruited into this study. The PD patients will all have a DAT SPECT scan which measures a marker of dopamine nerves. The PD and control patients will have an outpatient procedure in the office: a transcutaneous needle biopsy of the submandibular gland. This procedure just requires some local numbing medication. The tissue will then be treated with special stains and will be examined under a microscope to see if there are LTS changes present as are characteristic of PD.
Relevance to Diagnosis/Treatment of Parkinsonís Disease:†††††††††††††††††††††
The idea is that the submandibular gland biopsy would be a tissue-based diagnostic test for PD. This would allow for a significant increase in the clinical diagnostic accuracy of PD, even in the earlier stages. This would result in a more accurate subject selection for clinical trials, decision making on treatment plans, and patient identification for genetic, imaging, and other biomarker studies.
We expect to determine whether submandibular gland biopsies have the potential to diagnose PD. This is a small pilot study of 25 PD patients and 10 controls so that the information will be preliminary and would form the basis of a much larger project investigating submandibular gland biopsies in both advanced as well as earlier stages of PD.
Senior Scientist/Lab Head at Banner Sun Health Research Institute
Location: Sun City, Arizona, United States
Consultant and Professor, Department of Neurology at Mayo Clinic College of Medicine