AJCC 7th edition of TNM staging accurately discriminates outcomes of patients with resectable intrahepatic cholangiocarcinoma: by the AFC-IHCC-2009 study group

BACKGROUND: This year, the 7th edition of the AJCC staging manual has for the first time attributed a unique pTNM staging to intrahepatic cholangiocarcinoma (IHCC) that is intended to replace the 2 Western and ideally also the 2 Eastern systems currently in use. This proposal, which has not yet been validated, was tested in the current study. METHODS: Among 522 patients operated on with curative intent for an IHCC between 1994 and 2008 in tertiary hepatobiliary centers, those with mass-forming-type IHCCs, an R0 resection, and accurate pathological node staging were retained for evaluation. The distribution of these patients and their actuarial survival in the new TNM stages (as well as in the 4 previous ones) were compared. RESULTS: Only 163 patients fulfilled the inclusion criteria, mainly because of the lack of routine lymphadenectomy, but patients and tumors characteristics of this population were representative. These patients were evenly distributed between AJCC 7th edition stages (stage I, 28%; stage II, 32%; stage III, 35%), which was not the case for the other systems. With an average follow-up of 34 months in survivors, the AJCC 7th edition was more discriminating than the others in predicting survival (median for stage I not reached; for stage II, 53 months, P ¼ .01; for stage III, 16 months, P < .0001). Survival of these patients according to the 2 Japanese classifications was identical to that anticipated. CONCLUSIONS: The 7th edition is clinically relevant and may be applicable worldwide, provided routine lymphadenectomy at the time of surgery for IHCC becomes the standard of care.