The impact of metastatic sites on survival Rates and predictors of extended survival in patients with metastatic pancreatic cancer.

BACKGROUND OBJECTIVES: The aim of this study was to determine the role of site-specific metastatic patterns over time and assess factors associated with extended survival in metastatic PDAC. Half of all patients with pancreatic ductal adenocarcinoma (PDAC) present with metastatic disease. The site of metastasis plays a crucial role in clinical decision making due to its prognostic value. METHODS: We examined 56,757 stage-IV PDAC patients from the National Cancer Database (2016-2019), categorizing them by metastatic site: multiple, liver, lung, brain, bone, carcinomatosis, or other. The site-specific prognostic value was assessed using log-rank tests while time-varying effects were assessed by Aalen's linear hazards model. Factors associated with extended survival (>3years) were assessed with logistic regression. RESULTS: Median overall survival (mOS) in patients with distant lymph node-only metastases (9.0 months) and lung-only metastases (8.1 months) was significantly longer than in patients with liver-only metastases (4.6 months, p < 0.001). However, after six months, the metastatic site lost prognostic value. Logistic regression identified extended survivors (3.6 %) as more likely to be younger, Hispanic, privately insured, Charlson-index <2, having received chemotherapy, or having undergone primary or distant site surgery (all p < 0.001). CONCLUSION: While synchronous liver metastases are associated with worse outcomes than lung-only and lymph node-only metastases, this predictive value is diminished after six months. Therefore, treatment decisions beyond this time should not primarily depend on the metastatic site. Extended survival is possible in a small subset of patients with favorable tumor biology and good conditional status, who are more likely to undergo aggressive therapies.

Results following resection for stage IV gastric cancer; are better outcomes observed in selected patient subgroups?

BACKGROUND: Patients who present with stage IV gastric cancer are not commonly managed with surgical resection as effective palliation can usually be accomplished with systemic chemotherapy, endoscopic stenting, or surgical bypass procedures. Given the inherent morbidity and mortality associated with gastrectomy, palliative resection for stage IV gastric cancer should be reserved for ideal surgical candidates who are most likely to benefit from the procedure. The purpose of this study is to review outcomes following resection for stage IV gastric cancer, and to identify criteria predictive of improved outcomes following gastrectomy in this setting. METHODS: A retrospective review of a prospective GI oncology database was conducted. Sixty-three patients with stage IV gastric cancer managed with surgical resection between 1989 and 2001 were identified. Variables including demographic data, patterns of distant spread (ex: peritoneal, lymphatic, hematogenous), location of tumor, and type of gastrectomy were utilized to conduct survival analyses. RESULTS: Actuarial survival for all patients at one and 3-year intervals was 52% and 12%, respectively. Improved survival was observed for patients of East Asian race (median survival 20 vs. 12 months, P < 0.05, students t-test) and age less than 60 years (median survival 15 vs. 12 months, P < 0.05). This trend was also illustrated by Kaplan-Meier survival analysis. Other variables including pattern of distant spread, location of tumor, and type of gastrectomy were not associated with a significant difference in survival. Both East Asian race and age less than 60 years were statistically significant predictors of improved survival when assessed by univariate regression analysis. When variables were analyzed in a multivariate regression analysis, Asian race and age <60 both lost their statistical significance as independent predictors of improved survival. CONCLUSIONS: Long-term survival for patients with stage IV gastric cancer who are managed with surgical resection is achievable. Patient specific variables including East Asian race and age less than 60 years appear to be associated with prolonged survival when assessed by comparison of means, Kaplan-Meier analysis, and univariate regression analysis. However, multivariate regression analysis failed to demonstrate these factors as independent predictors of improved outcome. In conclusion, highly selected acceptable risk surgical candidates with stage IV gastric cancer should be considered for management with surgical resection in clinically appropriate scenarios.