Tohoku J. Exp. Med., 2009, 217(1)

Correct Diagnosis of Vascular Encasement and Longitudinal Extension of Hilar Cholangiocarcinoma by Four-Channel Multidetector-Row Computed Tomography

TADAYUKI OKUMOTO,¹ AKIHIRO SATO,² TAKAYUKI YAMADA,¹ KEI TAKASE,¹ TOSHIO MATSUHASHI,¹ MASASHI TSUDA,¹ KAZUMASA SEIJI,¹ TADASHI ISHIBASHI,³ SHUICHI HIGANO,¹ YU KATAYOSE,⁴ MICHIAKI UNNO⁴ and SHOKI TAKAHASHI¹

¹Department of Diagnostic Radiology, Tohoku University Graduate School of Medicine, Sendai, Japan
²Department of Radiology, Sendai Medical Center, Sendai, Japan
³Course of Health Sciences, Tohoku University Graduate School of Medicine, Sendai, Japan
⁴Department of Gastroenterological Surgery, Tohoku University Graduate School of Medicine, Sendai, Japan

Accurate diagnosis of local invasion of hilar cholangiocarcinomas is challenging due to their small size and the anatomic complexity of the hepatic hilar region. On the other hand, the correct diagnosis of local invasion is essential for assuring the possibility of curative surgery. The purpose of this study was to evaluate the feasibility of four-channel multidetector-row computed tomography (MDCT) in the assessment of vascular and bile duct involvement, by which we could obtain useful information for the surgical management of hilar cholangiocarcinoma. The subjects were 18 patients for whom the extent of tumor invasion was surgically and pathologically confirmed. All patients underwent preoperative multiphasic CT scanning by MDCT. Arterial and portal dominant phases were acquired using a detector configuration of 1.25 mm × 4 mm, and both axial and multiplanar reconstructed images were interpreted. Longitudinal extension was evaluated up to second-order branches. Vascular invasion is considered to be the degree of tumor contiguity to the hepatic arteries and portal vein and was graded by CT. The longitudinal extension was correctly diagnosed in 14 patients (77.8%). Hepatic artery invasion was correctly diagnosed in 17 patients with sensitivity of 100% and specificity of 90%, respectively. Portal vein invasion was correctly diagnosed in 47 of 51 branches with sensitivity and specificity of 92.3% and 90.2%, respectively. Multiplanar reconstructed images contributed to the correct diagnosis for both vascular encasement and longitudinal tumor extension. In conclusion, MDCT is useful in preoperative evaluation of hilar cholangiocarcinoma, especially when combined with multiplanar reconstructed images.

keywords —— Hilar cholangiocarcinoma; preoperative evaluation; diagnostic radiology; multidetector-row computed tomography; multiplanar reconstruction.

© 2009 Tohoku University Medical Press

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Tohoku J. Exp. Med., 2009, 217, 1-8

Correspondence: Tadayuki Okumoto, MD, Department of Diagnostic Radiology, Tohoku University Graduate School of Medicine, 1-1 Seiryo-machi, Aoba-ku, Sendai 980-8574, Japan.

e-mail: okumoto@rad.med.tohoku.ac.jp