Complete regression of intrahepatic cholangiocarcinoma after right portal vein ligation. Case report.

INTRODUCTION: Spontaneous tumor regression is an extremely rare phenomenon in the oncology field.

PRESENTATION OF CASE: We present the case of a 72-years-old male patient presenting with a bulky hepatic tumor mass located in segment V and extending into segments IVb and VI with MRI features of atypical cholangiocarcinoma with a liver metastasis in segment III. In first surgical step, excision of the metastasis, and ligation of the right portal vein was done. A new MRI examination performed 5 weeks later shows significant tumor regression, and 2 weeks later, during the second surgery, the tumor was not found. Under these conditions we performed a limited segment V liver resection, in the area indicated by the radiologist as the site of the tumor. No viable malignant cells existed in the tumor specimen, and a third MRI examination didn't identify any residual tumor.

DISCUSSION: From our literature study this is the only case of complete tumor regression of an intrahepatic cholangiocarcinoma following portal vein ligation. We believe the portal vein ligation resulted in a marked regression/deficiency in the tumor blood supply.

CONCLUSION: Serial MRI examinations demonstrated the regression of intrahepatic cholangiocarcinoma after portal vein ligation. Intrahepatic cholangiocarcinoma should be included in the tumors that could extremely rarely spontaneously regress.