The study by Pejhan et al. provides an important contribution to the ongoing debate regarding the significance of isolated angiitis of the vasa vasorum (AVV) and peri-adventitial small vessel vasculitis (SVV) in temporal artery biopsies.
Reference Pejhan, Barra and Basharat1
Through the re-examination of 72 biopsies paired with clinical follow-up, the authors demonstrate that isolated AVV/SVV is not a benign or incidental finding but instead identifies a subgroup of patients at higher risk of either harboring giant cell arteritis (GCA) or developing it over time.
Several strengths of this work deserve emphasis. The blinded re-assessment of all biopsies with standardized criteria, combined with integration of one–year clinical outcomes, provides a robust methodological framework. The finding that all biopsy-proven temporal arteritis cases were accompanied by small-vessel inflammation reinforces the biological link between AVV/SVV and GCA. Equally notable is the observation that 26% of patients with isolated AVV/SVV subsequently acquired a clinical diagnosis of GCA, a rate twice as high as in patients with non-inflamed biopsies. These data support the concept that AVV/SVV may represent an early, focal or partially treated stage of GCA, particularly in patients with high pre-test clinical probability.
The study also highlights important practical issues. Sampling variability and treatment-related modifications remain major challenges in temporal artery biopsy interpretation. The authors’ photomicrographic demonstration of spatial heterogeneity, with TA and AVV/SVV co-existing in different biopsy segments, underscores the risk of misclassification when sections are limited or non-serial.
Reference Cavazza, Muratore and Boiardi2
This strongly argues for a standardized, semi-serial histopathologic approach and for uniform reporting of small-vessel changes.
Nevertheless, some limitations warrant consideration. The single-center design and relatively modest cohort size may limit generalizability, and the semi-quantitative characterization of inflammatory cell subsets does not allow for deeper immunophenotypic insights. Broader validation in multi-institutional cohorts, ideally with integration of molecular or immunoprofiling approaches, will be valuable. Moreover, the absence of universally accepted diagnostic criteria for AVV/SVV remains a major barrier to consistent interpretation across pathology practices.
Reference Restuccia, Cavazza and Boiardi3–Reference Belilos, Maddox and Kowalewski5
Overall, this article makes a compelling case for the clinical relevance of isolated AVV/SVV and calls for a shift in how these findings are interpreted. Rather than being dismissed as “nonspecific,” they should be recognized as potentially actionable histopathologic markers, prompting closer clinical surveillance and follow-up. The study represents a significant step toward resolving a long-standing diagnostic gray zone in temporal artery pathology and has meaningful implications for both pathologists and clinicians involved in the care of patients at risk for vision- and life-threatening complications of GCA.
The study by Pejhan et al. provides an important contribution to the ongoing debate regarding the significance of isolated angiitis of the vasa vasorum (AVV) and peri-adventitial small vessel vasculitis (SVV) in temporal artery biopsies. Reference Pejhan, Barra and Basharat1 Through the re-examination of 72 biopsies paired with clinical follow-up, the authors demonstrate that isolated AVV/SVV is not a benign or incidental finding but instead identifies a subgroup of patients at higher risk of either harboring giant cell arteritis (GCA) or developing it over time.
Several strengths of this work deserve emphasis. The blinded re-assessment of all biopsies with standardized criteria, combined with integration of one–year clinical outcomes, provides a robust methodological framework. The finding that all biopsy-proven temporal arteritis cases were accompanied by small-vessel inflammation reinforces the biological link between AVV/SVV and GCA. Equally notable is the observation that 26% of patients with isolated AVV/SVV subsequently acquired a clinical diagnosis of GCA, a rate twice as high as in patients with non-inflamed biopsies. These data support the concept that AVV/SVV may represent an early, focal or partially treated stage of GCA, particularly in patients with high pre-test clinical probability.
The study also highlights important practical issues. Sampling variability and treatment-related modifications remain major challenges in temporal artery biopsy interpretation. The authors’ photomicrographic demonstration of spatial heterogeneity, with TA and AVV/SVV co-existing in different biopsy segments, underscores the risk of misclassification when sections are limited or non-serial. Reference Cavazza, Muratore and Boiardi2 This strongly argues for a standardized, semi-serial histopathologic approach and for uniform reporting of small-vessel changes.
Nevertheless, some limitations warrant consideration. The single-center design and relatively modest cohort size may limit generalizability, and the semi-quantitative characterization of inflammatory cell subsets does not allow for deeper immunophenotypic insights. Broader validation in multi-institutional cohorts, ideally with integration of molecular or immunoprofiling approaches, will be valuable. Moreover, the absence of universally accepted diagnostic criteria for AVV/SVV remains a major barrier to consistent interpretation across pathology practices. Reference Restuccia, Cavazza and Boiardi3–Reference Belilos, Maddox and Kowalewski5
Overall, this article makes a compelling case for the clinical relevance of isolated AVV/SVV and calls for a shift in how these findings are interpreted. Rather than being dismissed as “nonspecific,” they should be recognized as potentially actionable histopathologic markers, prompting closer clinical surveillance and follow-up. The study represents a significant step toward resolving a long-standing diagnostic gray zone in temporal artery pathology and has meaningful implications for both pathologists and clinicians involved in the care of patients at risk for vision- and life-threatening complications of GCA.
Competing interests
The author declares no competing interests.