Carcinogenesis and Cancer Progression in De Novo Anal Squamous Cell Carcinoma After Organ Transplantation: A Systematic Review.

Abstract

Our aim was to perform a comprehensive literature review on the pathogenesis of squamous anal cancerin patients after solid-organ transplant. Medical databases were consulted until June 1, 2020, for potentially relevant publications.All studies on pathogenesis of de novo anal squamous cell carcinoma in solid-organ transplant recipients were included. Two researchers independently performed study selection, quality assessment, and data extraction and analysis. Twenty-one studies were included.None ofthe selected papers had been solely focused on carcinogenesis. Most ofthe studies identified human papillomavirus infection and immunosuppression to be significantly correlated with the development of de novo anal cancer in adult solid organ transplant recipients. CD4+ T-cell depletion and inactivation oftumor suppressor pathways were mainly implicated. All solid-organ transplant recipients, especially those who were human papillomavirus positive, were shown to be at increased risk for the development of posttransplant anal cancer. Further studies are needed to determine the specific mechanisms of pathogenesis according to different solid-organ transplant populations.