Japanese Journal of Clinical Oncology, 2015, 45(6) 605–606 doi: 10.1093/jjco/hyv059 Advance Access Publication Date: 15 April 2015 Image of the Month
Image of the Month
An exophytic hepatic metastasis of mucinous colon cancer Hiroshi Nagata1,2,*, Ken Hayashi1, and Makio Mike1 1
Department of General Surgery, Kameda Medical Center, Kamogawa, Chiba, and 2Department of Surgical Oncology, The University of Tokyo Hospital, Bunkyo, Tokyo, Japan
*For reprints and all correspondence: Hiroshi Nagata, E-mail: [email protected] Downloaded from http://jjco.oxfordjournals.org/ by guest on March 15, 2016
Figure 2. Figure 1.
Figure 3.
Figure 4.
A 67-year-old woman with a chief complaint of abdominal mass was found to have an elastic-hard irregular tumour in her right lower quadrant on physical examination. Laboratory results indicated mild anaemia and elevated carcinoembryonic antigen and carbohydrate antigen 19-9 levels. Colonoscopy revealed a 40-mm adenocarcinoma in her ascending colon. Computed tomography incidentally detected a low-attenuation hepatic tumour projecting from the left
lateral segment, with rim enhancement under contrast imaging (Fig. 1, arrow). Ultrasonography revealed a homogeneously hypoechoic mass without through-transmission or hyperechoic rim. The mass appeared as low intensity on T1-weighted (Fig. 2A, arrowhead), high intensity with internal septation on T2-weighted (Fig. 2B, arrowhead) and low intensity on diffusion-weighted magnetic resonance imaging. Fluorodeoxyglucose (FDG)-positron emission
© The Author 2015. Published by Oxford University Press. All rights reserved. For Permissions, please email: [email protected]
605
606
Image of the Month
tomography indicated strong uptake by the ascending colon carcinoma, but no uptake by the hepatic mass. Ten years previously, the liver tumour was not observed on computed tomography. As malignancy could not be excluded, she underwent partial hepatectomy concurrent with laparoscopic-assisted right hemi-colectomy (Fig. 3). The exophytic whitish tumour histopathologically showed a mucinous adenocarcinoma within the normal hepatic tissue (Fig. 4). The ascending colon cancer was also a mucinous adenocarcinoma; no lymph node metastasis was noted. As both tumours were CK7− and CK20−, she was finally diagnosed with mucinous adenocarcinoma of the ascending colon with a solitary liver metastasis (T3N0M1a Stage IVA). She underwent 6 months of mFOLFOX6 treatment and has been disease-free for 1 year post-operatively.
The typical radiological features of mucinous carcinoma are relatively unclear, as they are largely dependent on the mucinous component proportion. In this case, our pre-operative diagnosis was biliary cystadenoma. Although ultrasonography suggested haemangioma, we assumed that the mass was cystic due to the insignificant diffusion restriction and negative FDG uptake. The difference in FDG accumulation between the primary tumour and the liver metastasis could be attributed to the tubular component proportion of the adenocarcinoma. Cytokeratin phenotyping, especially CK20 and CK7, is invaluable for identifying the primary tumour site. Although colorectal cancer typically shows a CK20+/CK7− profile, 9–15% of colon cancers and ∼28.6% of mucinous carcinomas express a CK20−/CK7− pattern.
Downloaded from http://jjco.oxfordjournals.org/ by guest on March 15, 2016
Image of the Month
An exophytic hepatic metastasis of mucinous colon cancer Hiroshi Nagata1,2,*, Ken Hayashi1, and Makio Mike1 1
Department of General Surgery, Kameda Medical Center, Kamogawa, Chiba, and 2Department of Surgical Oncology, The University of Tokyo Hospital, Bunkyo, Tokyo, Japan
*For reprints and all correspondence: Hiroshi Nagata, E-mail: [email protected] Downloaded from http://jjco.oxfordjournals.org/ by guest on March 15, 2016
Figure 2. Figure 1.
Figure 3.
Figure 4.
A 67-year-old woman with a chief complaint of abdominal mass was found to have an elastic-hard irregular tumour in her right lower quadrant on physical examination. Laboratory results indicated mild anaemia and elevated carcinoembryonic antigen and carbohydrate antigen 19-9 levels. Colonoscopy revealed a 40-mm adenocarcinoma in her ascending colon. Computed tomography incidentally detected a low-attenuation hepatic tumour projecting from the left
lateral segment, with rim enhancement under contrast imaging (Fig. 1, arrow). Ultrasonography revealed a homogeneously hypoechoic mass without through-transmission or hyperechoic rim. The mass appeared as low intensity on T1-weighted (Fig. 2A, arrowhead), high intensity with internal septation on T2-weighted (Fig. 2B, arrowhead) and low intensity on diffusion-weighted magnetic resonance imaging. Fluorodeoxyglucose (FDG)-positron emission
© The Author 2015. Published by Oxford University Press. All rights reserved. For Permissions, please email: [email protected]
605
606
Image of the Month
tomography indicated strong uptake by the ascending colon carcinoma, but no uptake by the hepatic mass. Ten years previously, the liver tumour was not observed on computed tomography. As malignancy could not be excluded, she underwent partial hepatectomy concurrent with laparoscopic-assisted right hemi-colectomy (Fig. 3). The exophytic whitish tumour histopathologically showed a mucinous adenocarcinoma within the normal hepatic tissue (Fig. 4). The ascending colon cancer was also a mucinous adenocarcinoma; no lymph node metastasis was noted. As both tumours were CK7− and CK20−, she was finally diagnosed with mucinous adenocarcinoma of the ascending colon with a solitary liver metastasis (T3N0M1a Stage IVA). She underwent 6 months of mFOLFOX6 treatment and has been disease-free for 1 year post-operatively.
The typical radiological features of mucinous carcinoma are relatively unclear, as they are largely dependent on the mucinous component proportion. In this case, our pre-operative diagnosis was biliary cystadenoma. Although ultrasonography suggested haemangioma, we assumed that the mass was cystic due to the insignificant diffusion restriction and negative FDG uptake. The difference in FDG accumulation between the primary tumour and the liver metastasis could be attributed to the tubular component proportion of the adenocarcinoma. Cytokeratin phenotyping, especially CK20 and CK7, is invaluable for identifying the primary tumour site. Although colorectal cancer typically shows a CK20+/CK7− profile, 9–15% of colon cancers and ∼28.6% of mucinous carcinomas express a CK20−/CK7− pattern.
Downloaded from http://jjco.oxfordjournals.org/ by guest on March 15, 2016
