Surgical treatment and postoperative outcomes for middle and lower bile duct carcinoma in Japan - Experience of a single institute

Background/Aims: Recently, the Japanese Classification on Cancer of the Biliary Tract was revised and adopted the new comprehensive staging that is similar to UICC's TNM classification. We should be paying close attention to the significance of newly defined extensive factors of carcinomas on the long-term prognosis. Methodology: The surgical outcome for 99 patients who underwent resected middle (Bm) and lower (Bi) bile duct carcinomas was reviewed in order to evaluate the suitability of the surgical procedures employed for their treatment, namely, standard pancreatoduodenectomy for Bi carcinoma and bile duct resection with D2 lymph node dissection for Bm carcinoma. Results: The overall 5-year cumulative survival rate (operative death excluded) of Bm and Bi carcinoma patients was 37.4% and the 5-year survival rate of the patients in whom surgical curability (curA) was accomplished was 51.6%. Recently, a new prognostic factor, 't-category', which indicates the degree of pericholedochal neoplastic invasion was proposed in the 4th edition of the Japanese General Rules for Surgical and Pathological Studies on Canaer of the Biliary Tract. The 10-year survival rates by t-category were 49.1% (t1), 19.7% (t2), and 0% (t3 and t4) respectively. For Bm carcinoma, the patients undergoing bile duct resection under the condition of curA skewed excellent prognoses. For Bi carcinoma, the patients fulfilling particular histological criteria, i.e., those concerning the histological depth of neoplastic invasion (m, fm, panc1a), duodenal involvement (du0, du1), vascular invasion (pv0), pericholedocal neoplastic invasion (t1), lymph node metastasis (n0), and comprehensive stage I, had good postoperative outcomes. Taking into account the fact that the metastatic rate of paragastric lymph nodes was 1.3% the cases of panc0,1 should be operated by pylorus-preserving pancreatoduodenectomy. The overall 5-year survival rates including far-advanced cases were 39.9% in Bm carcinoma patients and 36.9% in Bi carcinoma patients. However, these postoperative outcomes are far from satisfactory. Conclusions: Therefore, we concluded that pancreatoduodenectomy and pylorus-preserving pancreatoduodenectomy with extended D3 lymphadenectomy combined with systematic multimodal therapy are indicated in each and every case of Bm and Bi carcinoma.