J Korean Radiol Soc.  1995 Mar;32(3):441-446. 10.3348/jkrs.1995.32.3.441.

Preoperative Assessment of Rectal Cancer: Value of Two-Phase Dynamic CT

• Kwag JG
• Cho JS
• Oh YR
• Choi CL
• Rhee BC
• Kang GH

• KMID: 2465320
• DOI: http://doi.org/10.3348/jkrs.1995.32.3.441

Abstract

PURPOSE
The purpose of this study was to evaluate the utility of two-phase dynamic CT, early and equilibrium pahse, in the preoperative staging of rectal cancers.
MATERIALS AND METHODS
We performed incremental dynamic CT after rectal infusion of water in 34 patients with pathologically proved rectal cancers. Two-phase dynamic CT findings were prospectively analyzed and correlated with surgical and histopathologic findings. A total of 150ml of nonionic contrast medium was intravenously administered with a power injector at a flow rate of 5ml/sec for 30 sec, and two-phase images were obtained at 30 sec(early phase) and 2 min (equilibrium phase) after bolus injection. Local tumor staging and regional lymph node were classified by TNM staging.
RESULTS
All 34 rectal cancers showed a moderate to marked enhancement in the early phase and a homogeneous and prolonged enhancement of the entire lesion in the equilibrium phase. T-staging of primary tumors were 85.3%(29/34) in early phase and 70.6%(24/34) in equilibrium phase. The accuracy in determining the perirectal fat invasion of rectal cancer was 92%(23/25) in early phase, and 72%(18/25) in equilibrium phase. The sensitivity & specificity of the regional lymph node metastasis were 63.6% and 79.1% in early phase, and 54.5% and 65.2% in equilibrium phase, respectively.
CONCLUSION
Early phase dynamic CT was more accurate for the preoperative staging of rectal cancer than that at equilibrium phase.

MeSH Terms

Humans
Lymph Nodes
Neoplasm Metastasis
Neoplasm Staging
Prospective Studies
Rectal Neoplasms*
Sensitivity and Specificity
Water
Water