Abstract: TH-PO1113
Intravascular Large B-Cell Lymphoma Confined to Peritubular Capillaries Mimicking Interstitial Nephritis and Tubular Injury
Session Information
- Pathology and Lab Medicine
October 22, 2026 | Location: Exhibit Hall A, Convention Center
Abstract Time: 10:00 AM - 12:00 PM
Category: Pathology and Lab Medicine
- 1700 Pathology and Lab Medicine
Authors
- Zhu, Ye, Shanghai Jiao Tong University Medical School Affiliated Ruijin Hospital, Shanghai, China
- Pan, Xiaoxia, Shanghai Jiao Tong University Medical School Affiliated Ruijin Hospital, Shanghai, China
- Xu, Jing, Shanghai Jiao Tong University Medical School Affiliated Ruijin Hospital, Shanghai, China
Introduction
IVLBCL is a rare subtype of non-Hodgkin lymphoma characterized by malignant B-cell accumulation within small vessel lumina. Renal involvement is exceedingly rare.
Case Description
A 60-year-old female developed anuria, fever and a hemorrhagic rash on the extremities. Laboratory evaluation: serum creatinine (6.92mg/dl), platelet count (74×10^9/L), serum lactate dehydrogenase (616U/L), COVID-19 PCR positive. CT: Both kidneys are enlarged with uneven density. A kidney biopsy showed prominent dilatation of peritubular capillaries, containing a large number of atypical neoplastic cells, which exhibited enlarged, hyperchromatic nuclei with increased mitotic activity. Neutrophils and red blood cells were also present within the peritubular capillaries (Figure 1A). A similar cellular compositions were also present within few glomerular capillaries (Figure 1B). Bone marrow biopsy suggested slightly increased lymphocytes (large cell bodies with visible nucleoli, no obvious sinusoidal distribution). Immunohistochemistry showed CD34 (–, vascular+) (Figure 1C), CD79a (+) (Figure 1D), CD20 (3+) (Figure 1E), CD3 (-), MUM-1 (+), CD22 (+), CD19 (+/-), Bcl-2 (+) 60%, Bcl-6 (+), C-myc (+) 10%, CD5 (-), CD30 (-), EBER(-). Final Diagnosis: intravascular large B-cell lymphoma (hemophagocytic type). The patient received an R-COP regimen combined with etoposide and ruxolitinib, but died 1.5 months later.
Discussion
IVLBCL may present as intraglomerular or peritubular capillary (PTC)-predominant disease, the latter being particularly rare. Marked intraluminal accumulation of lymphoma cells can extensively distend PTCs, creating a pseudotubular appearance that mimics tubular injury or interstitial nephritis, particularly in the setting of concurrent infection and inflammatory cell admixture. In cases with diffuse cellular infiltration and significant renal enlargement, early immunohistochemical evaluation is essential to avoid diagnostic delay.
Acknowledgment
We are grateful to Professor Anthony Chang from University of Chicago for his valuable insights and constructive suggestions that improved this work.