R0 Resection Group Research Articles

Immunohistochemical detection of pS2 protein and heat shock protein-70 in pancreatic adenocarcinomas. Relationship with disease extent and patient survival.

We investigated pS2 and HSP-70 protein expression in 36 pancreatic adenocarcinomas for their effect on disease extent and patient outcome. The cases were reviewed, histologically diagnosed, typed, graded, and staged. Lymphatic vessel, blood vessel and perineural invasion as well as lymph node, resection margin and adjacent organ involvements were re-evaluated. The standard streptavidin biotin immunperoxidase method was used for immunostaining with pS2 and HSP-70 antibodies. Cytoplasmic staining with both antibodies was scored semiquantitatively. The scores were compared with histopathological prognostic parameters using statistical methods. Standard prognostic parameters and staining scores were tested by survival analysis in terms of their effect on survival. All the tumors showed a positive cytoplasmic reaction with HSP-70 antibody. Seventy-seven percent of the tumors showed positive cytoplasmic staining with pS2 antibody (22.2% +, 13.9% ++ and 41.7% +++). There was a statistically significant difference between HSP-70 staining scores with N status and final stages of the tumors (Chi-square, p = 0.03 and p = 0.026, respectively), while neither direct nor inverse correlation was detected for both parameters. PS2 staining scores showed no statistically significant relationship with tumor grade T, M status, perineural invasion, lymph and blood vessel invasion. In tumors with extensive staining with pS2, tumor stage tended to be low (Chi square, p = 0.024, Kendall Tau-b, r: -0.336, p = 0.036). There was a statistically significant difference and inverse correlation between tumors with extensive pS2 staining and tumors with less intense staining in terms of lymph node metastasis (Chi-square, p = 0.041, Kendall Tau: p = 0.024, r = -0,373). In the R0 resection group, in univariate analysis, we found that with higher scores of HSP-70 staining, the prognosis of the patient tended to improve. (Cox regression, p = 0.013). In multivariate analysis, HSP-70 expression was found to be an independent prognostic factor. We found no relationship between pS2 staining and patient survival.

Liver metastases after curative resection in patients with distal bile duct cancer.

Curative resection cannot ensure long-term survival for patients with distal bile duct cancer. The aim of this study was to determine the most frequent mode of recurrence after curative resection and to analyse its risk factors. Clinical details for 64 consecutive patients with distal bile duct cancer who underwent surgical resection between 1980 and 1997 were reviewed. Modes of recurrence and clinicopathological findings were analysed based on the residual tumour (R) classification. The overall actuarial 5-year survival rate was 32 per cent. Of 42 patients undergoing R0 resection 10 were alive at 5 years, of 17 having R1 resection one was alive at 5 years, and none of the five patients having R2 resection survived for 5 years (R0 versus R1, P = 0.02). In the R0 group, the incidence of liver recurrence (14 of 42 patients) was similar to that in the R1 resection group (six of 17), although there were fewer lymph node and peritoneal recurrences than in patients who had R1 resection (P < 0.05). The high-risk factor for liver metastasis was microscopic vascular involvement. Important factors for survival were lymph node metastasis, microscopic vascular involvement and age. In addition, microscopic vascular involvement was the only independent factor for survival in the R0 group. R0 resection provided significant survival benefit but had no effect on liver recurrence. Therefore, new agents or strategies to prevent liver metastasis are necessary for improvement of survival.