Proteomic Identification and Clinicopathologic Characterization of Splenic Amyloidosis

作者：April Chiu, Surendra Dasari, Paul J. Kurtin, Jason David Theis, Julie A. Vrana, Karen L. Rech, Linda N. Dao, Matthew T. Howard, Joanna Dalland, Ellen Darcy McPhail · 发表于：The American Journal of Surgical Pathology · 年份：2022 · DOI：10.1097/pas.0000000000001948 · 被引用次数：10 · 研究领域：Amyloidosis: Diagnosis, Treatment, Outcomes、Pancreatitis Pathology and Treatment、Abdominal Trauma and Injuries

The spleen is a commonly encountered specimen in surgical pathology. However, little is known about the incidence, morphologic pattern, and clinical features of spleens involved by amyloidosis. We retrospectively identified 69 spleen amyloid cases typed using a proteomics-based method between 2008 and 2020. The frequency of amyloid types, clinicopathologic features, and distribution of amyloid deposits were assessed. Four amyloid types were detected: immunoglobulin light chain (AL) (N=30; 43.5%); leukocyte chemotactic factor 2 amyloidosis (ALECT2) (N=30; 43.5%); amyloid A (AA) (N=8; 11.6%); and fibrinogen alpha (AFib) (N=1; 1.4%). The splenic amyloid showed 5 distinct distribution patterns: (1) diffuse pattern, exhibited by most AL cases; (2) red pulp pattern, exhibited by most ALECT2 cases; (3) multinodular pattern, seen in subsets of AA and AL-kappa cases; (4) mass-forming pattern, seen in the AFib case; and (5) vascular only, seen in a subset of AA cases. Atraumatic splenic rupture was the most common reason for splenectomy in AL cases, while most ALECT2 spleens were removed incidentally during an unrelated abdominal surgery. Splenomegaly was significantly more common in AA spleens than in AL or ALECT2 spleens and was often the reason for splenectomy in this group. In conclusion, splenic amyloid may be underrecognized as it is often an incidental finding. Although, as expected, many of the spleens were involved by AL amyloidosis, ALECT2 emerged as another common spleen amy...