Related Experiment Video
Updated: Dec 11, 2025

Author Spotlight: Developing a Bedside Protocol for Kidney and Genitourinary Ultrasonography
Published on: June 21, 2024
Pseudocapsule of Small Renal Cell Tumors: CT Imaging Spectrum and Correlated Histopathological Features
Gang Li1, Xianqi Lu2, Yunsheng Ding3
1Department of Urology, The Second Hospital of Tianjin Medical University, Tianjin Institute of Urology, Tianjin City, 300211, China. drgangli2001@sina.com.
Purpose:
To systematically analyze histopathologic features of pseudocapsule in small renal cell tumor (diameter≤4cm), assess the integrity of pseudocapsules by Computed Tomography (CT), and provide theoretical basis for the safety of nephron sparing surgery.
Materials And Methods:
The pathological data of 116 patients who underwent surgery with clear cell renal cell carcinoma admitted from May 2010 to October 2017 were retrospectively analyzed. All patients underwent a CT scan of the abdomen including an unenhanced and triple-phase (arterial, nephrographic and excretory) post contrast series."All patients underwent a CT scan of the abdomen including an unenhanced and triple-phase (arterial, nephrographic and excretory) post contrast series."All patients underwent a CT scan of the abdomen including an unenhanced and triple-phase (arterial, nephrographic and excretory) post contrast seriesAll patients underwent a CT scan of the abdomen including an unenhanced and three-phase (arterial, nephrographic and excretory) post contrast series. Thorough gross examination and histological sections were used to determine the integrity of the pseudocapsule by two uropathologists. The consistency between pathological findings and CT imaging were evaluated by Kappa consistency test.
Results:
The mean diameter of tumor was 3.0cm, range (2.6 ± 0.8) cm. On CT the pseudocapsule can present with one of the three following feathers:1) A regular and distinct halo; 2)lobulated clear margins;3) blurred margins. On histopathology, complete psuedocapsule was found in 85 tumors, incomplete psuedocapsule in 25 and no psuedocapsule was found in 6 tumors; CT scan findings demonstrated a regular halo in 82 tumors, lobulated clear margins in 26 and blurred margins in 8 tumors(Kappa=0.833,P=0.000).
Conclusions:
Most small renal cell tumors have an obvious psuedocapsule. Preoperative determination of the psuedocapsule's integrity is particularly important. CT scan can reliably evaluate the tumor margins and demonstrate the psuedocapsule when present. The imaging results are well correlated with the pathologic findings.
More Related Videos
Related Concept Videos
Imaging Studies I: Kidney, Ureter, and Bladder Studies
Renal Corpuscle
Glomerulus: Structure and Function
The glomerulus is a tiny, intricate network of capillaries located at the beginning of the nephron. It's enveloped by the Bowman's capsule and receives its blood supply from an afferent arteriole, which divides into numerous...
External Anatomy of the Kidney
The kidneys are located in the retroperitoneal space on either side of the vertebral column, protected posteriorly by the 11th and 12th ribs. The right kidney sits slightly lower than the left owing to the presence of the liver...
Imaging Studies III: Computed Tomography
Internal Anatomy of the Kidney
Anatomical Position and Dimensions
The kidneys are retroperitoneal organs positioned against the posterior abdominal wall on either side of the spine, roughly between the twelfth thoracic and third lumbar vertebrae. Each kidney is typically 10-12 cm long, 5-6 cm wide, and 3-4 cm thick, weighing about 150 grams.
Renal Cortex
The outermost region of the kidney is the...
Renal Tubule and Collecting Duct
Proximal Convoluted Tubule (PCT):
The PCT is the initial segment of the renal tubule, extending from the Bowman's capsule that encloses the glomerulus. Its convoluted structure and microvilli-lined cells increase the surface area for reabsorption. The PCT reabsorbs glucose, amino acids, sodium, and water from the filtrate, ensuring essential...

