Sun Choon Song, et al. section is often non-curative [10]. To this end, therapeutic strategies for advanced or metastatic cholangiocarcinoma have been developed, such as systemic chemotherapy, brachytherapy, photodynamic therapy and hepatic-ar- terial embolization or cryoablation [7,10,19,26]. However, most have limited roles in representing satisfactory out- comes on survival. It is reported that liver and abdominal lymph nodes around the hepatoduodenal ligament, periportal, com- mon hepatic artery, and posterior pancreatoduodenal areas are common sites of recurrence in patients with chol- angiocarcinoma [5,19,27,28]. Occasionally, distant lymph nodes in the posterior mediastinum or supraclavicular area can be involved. These findings have commonly been accepted to reflect disease progression and are associated with a poor prognosis. Repeated liver resection in intrahepatic cholangio- carcinoma, repeated RFA, or a combination for locore- gional recurrent tumor have been reported to be effective with respect to survival in highly selected patients [9,17,18,25]. However, our study extended the concept of repeated resection beyond the liver to extrahepatic in- tra-abdominal locoregional recurrences, abdominal or chest wall and lung or pleura. In addition to performing repeated hepatectomy or RFA for recurrent hepatic le- sions, resection of recurrences in the abdominal cavity and abdominal or chest wall were attempted. In our experi- ence, there were two of five cases showing positive re- section margins after metastasectomy of the abdominal wall. Second recurrences occurred in these two patients, so they underwent repeated resection around the previous area of resection. Thus, wider excision must be considered during metastasectomy of the abdominal or chest wall, and mesh could be useful for covering large fascial defects in these cases. In this series, the recurrence rate of cholangiocarcinoma showed 34.3%, and about 57% of recurrence occurred within 1 year. However, only 8.3% of patients with re- currence were treated surgically in this period, while 10.0% and 19.6% of patients were treated from 1 to 2 years and above 2 years, respectively. Thus, early surgical re- section should be considered to acquire greater survival benefits. 192 There are some drawbacks in this retrospective study. First, differences in the clinical course and pathogenesis among the three types of cholangiocarcinoma may exist. But it was reported that there were no significant differ- ences in clinical presentation, disease stage and survival between intra- and extra-hepatic cholangiocarcinoma [6]. Second, a relatively smaller incidence of recurrence than in previous studies was identified. It might be influenced not by the development of the palliative treatment op- tions, but also missed patients who were previously treat- ed surgically. In fact, patients with cholangiocarcinoma have been increasing recently who were treated surgically or with RFA. Therefore, further follow-up studies for these patients are warranted to understand tumor biology and diverse patterns of tumor recurrence to make up for these limitations. Francis et al. [9] and Zhang et al. [4] in- troduced regulation of cholangiocarcinoma from a bio- logic point of view. Their reviews suggested that genetic hypermethylation, interleukin-6, growth factors, gastro- intestinal hormones, neuroregulatory molecules, angio- genesis, or E-cadherin-mediated cell-to-cell adhesion ex- pressed by the Slug gene are related to growth or invasive- ness of the tumor. Third, although most of the clin- icopathologic characteristics were similar in our two groups, the rate of patients who underwent adjuvant CCRT was higher in group A. This selection bias could be an interference factor in drawing our conclusion. Finally, overall survival has room for modification because the re- currence patterns between the two groups were not similar. Thus, further prospective controlled study is needed to overcome this limitation. In conclusion, according to this large-series study in a single center, we have to consider surgical procedures to resectable recurrent lesions to prolong survival in patients with recurrent cholangiocarcinoma. Moreover, adjuvant chemoradiotherapy alone could not acquire a meaningful beneficial outcome on survival without resection of re- current lesions. Although this series did not confirm any beneficial effect of surgical procedures to recurrent masses in the liver, lung, pleura, or multiple sites on survival, sur- gical resection of locoregional recurrence in the abdominal cavity and of the abdominal or chest wall metastatic le- sions showed remarkable benefits in terms of range of thesurgery.or.kr