Vascularized composite allotransplantation: a closer look at the banff working classification

Abstract

SUMMARYThe first Banff vascularized composite allotransplantation meeting was held in 2007 to standardize criteria for the characterization and reporting of severity and types of rejection. As a result, the 2007 Banff VCA working classification for skin allograft pathology was formalized and now serves as the standard for diagnosis of VCA rejection. Similar to other working classification systems, strengths and limitations have been identified including the adequacy of the specimen, the definition of severity between grades, the reproducibility, the adequacy of the specimens, the types of rejection, and the integration of newer technologies such as molecular and genomic approaches. Although a relatively few number of cases have been performed and followed up to date, additional phenotypes such as antibodymediated rejection, fibrosis, atrophy, and vascular changes are being reported and characterized based on accumulated experience in the field of VCA and parallels with other solid organs. This study aims to consider strengths and limitations of the Banff VCA working system and highlights ongoing challenges and opportunities available related to histopathology in this emerging field of transplantation.

Increased levels of circulating MMP3 correlate with severe rejection in face transplantation

“…Also, the routine 4 mm punch skin biopsy does not assess deeper allograft tissues for rejection. The histological assessment might be additionally prone to intra- and interobserver variability, since the differentiation between “mild” (grade I) and “moderate” (grade II) perivascular inflammatory infiltrate is not objectively defined 15 . Last but not least, the clinical relevance of mild forms of rejection (grade I) by Banff grading is unclear too and justifies the question whether grade I rejections in face transplantation should be treated 51 .…”

“…However, skin biopsy is associated with morbidity to the patient, including scarring, bleeding or infection, hence it is not favorable for frequent monitoring. Furthermore, the Banff grading of skin rejection is semiquantitative, might be prone to intra- and interobserver variability, and lacks a correlation to treatment response 12 – 15 . Thus, strategies to establish non-invasive monitoring, such as from blood samples, are very desirable for the clinical management as well as to define the best treatment strategy.…”

Systematic pathological component scores for skin-containing vascularized composite allografts

“…5,[9][10][11] The classification has been clinically useful in the diagnosis of rejection, however, the need for characterization of the pathologic features and a better understanding of mechanisms remain. 12,13 The findings in this study highlight the potential usefulness of a systematic approach to evaluation of rejection in allograft biopsies where pathologic patterns may overlap or not meet qualitative characteristics. The richness of this data allows for better clinical or research correlation and can give insights into the varied pathogenesis of rejection in VCA (e.g., epidermal vs. vascular).…”

Accommodation and related conditions in vascularized composite allografts

“…In contrast to the high incidence of CMR, acute antibody-mediated rejection (AMR) is rarely observed in VCA (10, 21–23). Weissenbacher et al (24) reported one case of AMR and recently reviewed the literature (25).…”