Pancreatic surgery

The Results of Pancreatic Resections and Long-Term Survival for Pancreatic Ductal Adenocarcinoma: A Single-Institution Experience

OBJECTIVES

Since the early 1990s, low long-term survival rates following pancreatic surgery for pancreatic ductal adenocarcinoma have challenged us to improve treatment. In this series, we aim to show improved survival from pancreatic ductal adenocarcinoma during the era of centralized pancreatic surgery.

METHODS

Analysis of all pancreatic resections performed at Helsinki University Hospital and survival of pancreatic ductal adenocarcinoma patients during 2000-2013 were included. Post-operative complications such as fistulas, reoperations, and mortality rates were recorded. Patient and tumor characteristics were compared with survival data.

RESULTS

Of the 853 patients undergoing pancreatic surgery, 581 (68%) were pancreaticoduodenectomies, 195 (21%) distal resections, 28 (3%) total pancreatectomies, and 49 (6%) other procedures. Mortality after pancreaticoduodenectomy was 2.1%. The clinically relevant B/C fistula rate was 7% after pancreaticoduodenectomy and 13% after distal resection, and the re-operation rate was 5%. The 5- and 10-year survival rates for pancreatic ductal adenocarcinoma were 22% and 14%; for T1-2, N0 and R0 tumors, the corresponding survival rates were 49% and 31%. Carbohydrate antigen 19-9 >75 kU/L, carcinoembryonic antigen >5 µg/L, N1, lymph-node ratio >20%, R1, and lack of adjuvant therapy were independent risk factors for decreased survival.

CONCLUSION

After centralization of pancreatic surgery in southern Finland, we have managed to enable pancreatic ductal adenocarcinoma patients to survive markedly longer than in the early 1990s. Based on a 1.7-million population in our clinic, mortality rates are equal to those of other high-volume centers and long-term survival rates for pancreatic ductal adenocarcinoma have now risen to some of the highest reported.

Inhibition of 5-lipoxygenase triggers apoptosis in pancreatic cancer cells

The 5-lipoxygenase (5-LOX) pathway has been associated with a variety of inflammatory diseases including asthma, atherosclerosis, rheumatoid arthritis, cancer and liver fibrosis. Several classes of 5-LOX inhibitors have been identified, but only one drug, zileuton, a redox inhibitor of 5-LOX, has been approved for clinical use. In the present study, 5-LOX was found to be overexpressed not only in pancreatic cancer cell lines but also in tissue samples of patients suffering from pancreatic adenocarcinoma. There was a close correlation between the tumor expression levels of 5-LOX mRNA and protein and the clinicopathological patient characteristics including lymph node metastasis and TNM stage. Zileuton suppressed the proliferation of SW1990 cells in a concentration- and time‑dependent manner. In addition, zileuton induced SW1990 cells to undergo apoptosis and significantly decreased 5-LOX expression. The number of apoptotic cells, estimated by flow cytometry, Annexin V/PI assay, TUNEL staining and sub‑diploid population was significantly higher than that of the control. These results suggest that the level of 5-LOX expression was increased in pancreatic cancer tissues and may be related to lymph node metastasis and TNM stage.

The anatomic location of pancreatic cancer is a prognostic factor for survival

BACKGROUND

Pancreatic cancers of the body and tail (BT) appear to have poorer survival compared with head (HD) lesions. We hypothesized that potential disparities in outcome may be related to tumor location. Our objective was to examine the relationship between tumor location and survival.

METHODS

The Surveillance, Epidemiology, and End Results registry identified 33,752 patients with pancreatic adenocarcinoma and 6443 patients who underwent cancer-directed surgery between 1988 and 2004. Differences in survival and relationships between tumor location and clinical factors were assessed. Multivariate analysis was performed to determine the prognostic significance of tumor location.

RESULTS

Median survival for the entire cohort was five months and was significantly lower for BT compared to HD lesions (four vs. six months, p<0.001). Distant metastases (67% vs. 36%, p<0.001) were greater and cancer-directed surgery (16% vs. 30%, p<0.001) was lower for BT tumors. Of 6443 resected patients, HD patients (n=5118) were younger, had a greater number of harvested lymph nodes, were more likely to be lymph node-positive, and had a higher proportion of T3/T4 lesions. Significant univariate predictors of survival included age, T-stage, number of positive and harvested lymph nodes. On multivariate analysis, BT location was a significant prognostic factor for decreased survival (OR 1.11, 95% CI 1.00-1.23, p=0.05).

DISCUSSION

Pancreatic BT cancers have a lower rate of resectability and poorer overall survival compared to HD lesions. Prospective large-cohort studies may definitively prove that tumor location is a prognostic factor for survival in patients with pancreatic cancer.

Enhanced Antitumor Effect of Combined Triptolide and Ionizing Radiation

PURPOSE

The lack of effective treatment for pancreatic cancer results in a very low survival rate. This study explores the enhancement of the therapeutic effect on human pancreatic cancer via the combination of triptolide and ionizing radiation (IR).

EXPERIMENTAL DESIGN

In vitro AsPC-1 human pancreatic cancer cells were treated with triptolide alone, IR alone, or triptolide plus IR. Cell proliferation was analyzed with sulforhodamine B (SRB) method and clonogenic survival; comparison of apoptosis induced by the above treatment was analyzed by annexin V-propidium iodide (PI) staining. Furthermore, the expression of apoptotic pathway intermediates was measured by the assay of caspase activity and Western blot. Mitochondrial transmembrane potential was determined by JC-1 assay. In vivo, AsPC-1 xenografts were treated with 0.25 mg/kg triptolide, 10 Gy IR, or triptolide plus IR. The tumors were measured for volume and weight at the end of the experiment. Tumor tissues were tested for terminal nucleotidyl transferase-mediated nick end labeling (TUNEL) and immunohistochemistry.

RESULTS

The combination of triptolide plus IR reduced cell survival to 21% and enhanced apoptosis, compared with single treatment. In vivo, tumor growth of AsPC-1 xenografts was reduced further in the group treated with triptolide plus IR compared with single treatment. TUNEL and immunohistochemistry of caspase-3 cleavage in tumor tissues indicated that the combination of triptolide plus IR resulted in significantly enhanced apoptosis compared with single treatments.

CONCLUSIONS

Triptolide in combination with ionizing radiation produced synergistic antitumor effects on pancreatic cancer both in vitro and in vivo and seems promising in the combined modality therapy of pancreatic cancer.