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Prognostic factors in patients with middle and distal bile duct cancers.

AIM
To identify the influence of the surgery type and prognostic factors in middle and distal bile duct cancers.


METHODS
Between August 1990 and June 2011, data regarding the clinicopathological factors of 194 patients with surgical and pathological confirmation were collected. A total of 133 patients underwent resections (R0, R1, R2; n = 102, 24, 7), whereas 61 patients underwent nonresectional surgery. Either pancreaticoduodenectomy (PD) or bile duct resection (BDR) was selected according to the sites of tumors and co-morbidities of the patients after confirming resection margin by the frozen histology in all cases. Univariate and multivariate analyses of clinicopathologic factors were performed, utilizing the Kaplan-Meyer method and Cox hazard regression analysis.


RESULTS
The overall 5-year survival rate for the 133 patients who underwent resection (R0, R1, and R2) was 41.2%, whereas no patients survived longer than 3 years among the 61 patient who underwent nonresectional surgeries. The 5-year survival rate of the patients who underwent a PD (n = 90) was higher than the rate of those who underwent BDR (n = 43), although the difference was not statistically significant (46.6% vs 30.0% P = 0.105). However, PD had a higher rate of R0 resection than BDR (90.0% vs 48.8%, P < 0.0001). If R0 resection was achieved, PD and BDR showed similar survival rates (49.4% vs 46.5% P = 0.762). The 5-year survival rates of R0 and R1 resections were not significantly different (49.0% vs 21.0% P = 0.132), but R2 resections had lower survival (0%, P = 0.0001). Although positive lymph node, presence of perineural invasion, presence of lymphovascular invasion (LVI), 7th AJCC-UICC tumor node metastasis (TNM) stage, and involvement of resection margin were significant prognostic factors in univariate analysis, multivariate analysis identified only TNM stage and LVI as independent prognostic factors.


CONCLUSION
PD had a greater likelihood of curative resection and R1 resection might have some positive impact. The TNM stage and LVI were independent prognostic factors.