Case Report
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World J Gastroenterol. Oct 21, 2013; 19(39): 6683-6688
Published online Oct 21, 2013. doi: 10.3748/wjg.v19.i39.6683
A rare case of primary choriocarcinoma in the sigmoid colon
Hiromitsu Maehira, Tomoharu Shimizu, Hiromichi Sonoda, Eiji Mekata, Tomoharo Yamaguchi, Tohru Miyake, Mitsuaki Ishida, Tohru Tani
Hiromitsu Maehira, Tomoharu Shimizu, Hiromichi Sonoda, Eiji Mekata, Tomoharo Yamaguchi, Tohru Miyake, Tohru Tani, Department of Surgery, Shiga University of Medical Science, Shiga 520-2192, Japan
Mitsuaki Ishida, Department of Clinical Laboratory Medicine, Shiga University of Medical Science, Shiga 520-2192, Japan
Author contributions: Maehira H and Shimizu T contributed equally to this work; Maehira H, Shimizu T, Sonoda H, Yamaguchi T, Miyake T and Mekata E performed surgical procedures and chemotherapy; Ishida M made the pathological diagnosis; Maehira H, Shimizu T and Tani T wrote the paper.
Correspondence to: Tomoharu Shimizu, MD, PhD, Senior Assistant Professor, Department of Surgery, Shiga University of Medical Science, Seta-tsukinowacho, Otsu, Shiga 520-2192, Japan. tomoharu@belle.shiga-med.ac.jp
Telephone: +81-77-548223 Fax: +81-77-5482240
Received: May 9, 2013
Revised: July 18, 2013
Accepted: August 12, 2013
Published online: October 21, 2013
Abstract

Primary colorectal choriocarcinoma is an extremely rare neoplasm and is usually associated with a poor prognosis. Only 13 cases of colorectal choriocarcinoma have previously been reported. There is no standard chemotherapeutic regimen for this tumor type. A 68-year-old man presented with melena and was diagnosed with sigmoid colonic adenocarcinoma with multiple liver metastases. He underwent a laparoscopic sigmoidectomy. Pathology revealed choriocarcinoma with a focal component of moderately differentiated adenocarcinoma of colon origin. Based on the collagen gel droplet-embedded culture drug sensitivity test (CD-DST) results, mFOLFOX6 and bevacizumab were administered, which suppressed aggressive tumor growth for 4 mo. The patient died 9 mo after the initial diagnosis. Our study results suggest that the standard chemotherapy regimen for colorectal cancer might have suppressive effects against primary colorectal choriocarcinoma. Moreover, CD-DST may provide, at least in part, therapeutic insight for the selection of appropriate antitumor agents for such patients.

Keywords: Colon cancer, Colorectal cancer, Chemotherapy, Culture drug sensitivity test, Choriocarcinoma

Core tip: Primary colorectal choriocarcinoma is an extremely rare neoplasm and is usually associated with a poor prognosis. Only 13 cases of colorectal choriocarcinoma have previously been reported. Systemic chemotherapy is an important prognostic factor in these patients; however, there is no standard chemotherapeutic regimen for this tumor type. We encountered an extremely rare case of choriocarcinoma of the colon which was treated with mFOLFOX6 and bevacizumab based on the results of the culture drug sensitivity test (CD-DST), which suppressed aggressive tumor growth. This suggests that CD-DST may provide, at least in part, therapeutic insight for selecting appropriate antitumor agents for patients with colorectal choriocarcinoma.