Temporal artery biopsy length does not affect rate of positive diagnosis in temporal arteritis: a retrospective review of 107 cases

Abstract

Purpose : Temporal artery biopsy (TAB) remains the gold standard in the diagnosis of giant cell arteritis (GCA)/temporal arteritis. Inadequate TAB specimen length is often cited as an explanation for negative diagnostic results. We investigated the relationship between the length of TAB and its diagnostic yield in a tertiary referral center in the United States over a six-year period.

Methods : A retrospective review was performed for all patients who underwent a TAB from January 2012 to October 2018 at UC San Diego Medical Center in San Diego, California. The patients’ histological details were obtained from the pathology department. Demographic data, laboratory findings, operation details, and clinical notes were reviewed to obtain management details. Student’s t-test and Fisher’s exact test were performed to determine statistical significance.

Results : We reviewed 107 biopsies from 36 men and 71 women. Patient ages ranged from 50 to 102 (mean = 71). The incidence of temporal arteritis in our series was 17.8% (19/107). There was no significant difference in the means of age between positive (75.05 ± 7.35 years) and negative (70.45 ± 12.33 years) TABs (p = 0.121). Among positive TABs, there were 13 female patients and 6 male patients, and among negative TABs there were 63 female patients and 25 male patients (p = 0.776). There was no significant difference in the biopsy length between positive (19.81 mm ± 5.71 mm) and negative (18.35 mm ± 5.96 mm) TABs (p = 0.346). In an analysis of the subset of patients with biopsy length under 20 mm, there was also no significant difference in the rate of positive versus negative results (p = 0.975). Additionally, biopsy length of at least 20 mm did not produce a statistically significant difference in diagnostic positivity (p = 0.745).

Conclusions : The percentage of positive TABs in our series was 17.8% and consistent with previous reports. We saw no correlation between the length of the TAB and positive temporal arteritis diagnoses. Furthermore, we found that shorter biopsy lengths did not correlate with increased risk of negative results, and longer biopsy lengths did not yield higher likelihood of positive results.

This abstract was presented at the 2019 ARVO Annual Meeting, held in Vancouver, Canada, April 28 - May 2, 2019.