Clinical Impact of Structured Post-Operative Surveillance in Resected Pancreatic Adenocarcinoma: Results from a Retrospective Cohort Study.

INTRODUCTION: To this date, surgery remains the only potentially curative approach in the treatment of pancreatic cancer. To analyse the clinical impact of a structured post-operative follow-up programme, we retrospectively analysed a cohort of resected pancreatic adenocarcinoma patients treated at LMU Munich. METHODS: Pancreatic adenocarcinoma patients who underwent resection and presented for regular follow-up visits at our centre between 2002 and 2017 were identified from two existing study cohorts. Diagnosis of recurrences was categorised by timing (within or outside a scheduled follow-up visit) and detection modality (imaging, CA 19-9 increase, or clinical deterioration) and correlated with disease-free survival and overall survival (OS). RESULTS: One hundred and twenty-five patients with resected pancreatic adenocarcinoma were included in this analysis. Median OS in the whole cohort was 21.1 months. Of these 125 patients, 103 (82.4%) patients had a documented relapse. Tumour recurrences detected within a scheduled follow-up visit (n = 86, 83.5%) compared to recurrences becoming apparent at an unplanned visit (n = 17, 16.5%) were associated with a significantly improved OS (median 25.5 vs. 20.2 months, p = 0.019). Compared to patients with recurrence detected by clinical deterioration (n = 4, 3.9%), patients with recurrences detected by imaging or laboratory abnormalities (n = 99, 96.0%) had a longer median OS (24.8 vs. 15.1 months, p = 0.007). DISCUSSION: A structured follow-up after pancreatic ductal adenocarcinoma resection may have an impact on patient outcome. Prospective trials are needed to evaluate the clinical impact of post-operative follow-up programmes.

Superior Overall Survival in Patients with Colorectal Cancer, Regular Aspirin Use, and Combined Wild-Type PIK3CA and KRAS-Mutated Tumors.

The impact of aspirin use after the diagnosis of colorectal cancer is unknown. Among others, PIK3CA (phosphatidylinositol-4,5-bisphosphate 3-kinase, catalytic subunit alpha) mutational status was proposed as a molecular biomarker for the response to adjuvant aspirin therapy. However, prognostic data on aspirin use after a colorectal cancer diagnosis in relation to KRAS mutational status is limited. In a single-center retrospective study, we obtained KRAS and PIK3CA mutational status in a cohort of 153 patients with a first diagnosis of colorectal cancer receiving tumor surgery with curative intent. PIK3CA mutational status was determined by pyrosequencing, and KRAS mutational status was determined by next-generation sequencing. Clinicopathological data and survival data were assessed using patient records and reporting registers. We observed a significant 10-year overall survival benefit in patients with aspirin use and combined wild-type PIK3CA and mutated-KRAS tumors (HR = 0.38; 95% CI = 0.17-0.87; p = 0.02), but not in patients without aspirin use. Our data indicate a benefit of aspirin usage particularly for patients with combined wild-type PIK3CA and mutated-KRAS tumor characteristics.

Quantitative Imaging Biomarkers of the Whole Liver Tumor Burden Improve Survival Prediction in Metastatic Pancreatic Cancer.

Finding prognostic biomarkers with high accuracy in patients with pancreatic cancer (PC) remains a challenging problem. To improve the prediction of survival and to investigate the relevance of quantitative imaging biomarkers (QIB) we combined QIB with established clinical parameters. In this retrospective study a total of 75 patients with metastatic PC and liver metastases were analyzed. Segmentations of whole liver tumor burden (WLTB) from baseline contrast-enhanced CT images were used to derive QIBs. The benefits of QIBs in multivariable Cox models were analyzed in comparison with two clinical prognostic models from the literature. To discriminate survival, the two clinical models had concordance indices of 0.61 and 0.62 in a statistical setting. Combined clinical and imaging-based models achieved concordance indices of 0.74 and 0.70 with WLTB volume, tumor burden score (TBS), and bilobar disease being the three WLTB parameters that were kept by backward elimination. These combined clinical and imaging-based models have significantly higher predictive performance in discriminating survival than the underlying clinical models alone (p < 0.003). Radiomics and geometric WLTB analysis of patients with metastatic PC with liver metastases enhances the modeling of survival compared with models based on clinical parameters alone.

Prolonged time to treatment initiation in advanced pancreatic cancer patients has no major effect on treatment outcome: a retrospective cohort study controlled for lead time bias and waiting time paradox.

PURPOSE: A prolonged time to treatment initiation (TTI) correlates with an adverse prognosis in different cancer types including resectable pancreatic cancer (PC). Only limited evidence on the correlation between TTI and prognosis in advanced PC exists. METHODS: Consecutive PC patients (n = 368) who were diagnosed or treated at our high-volume comprehensive cancer center were included in a prospectively maintained database. We retrospectively analyzed time from first imaging showing advanced PC to initiation of palliative first-line chemotherapy. Lead time bias and waiting time paradox were addressed by landmark analysis and correlation of tumor burden with TTI. RESULTS: Two hundred and ninety-seven patients met the pre-specified in- and exclusion criteria of our study. Median TTI was 29 days (range: 1-124 days). Most common reasons for prolonged TTI (> 21 days) were referral from an external treatment center (39%) and a second biopsy (31%). A TTI above the median-, 75th or 90th percentile (43 or 60 days, respectively) had no impact on overall survival. Furthermore, no correlation between levels of carbohydrate antigen 19-9 (CA 19-9) at time of treatment initiation and TTI was observed. CONCLUSION: While a timely work-up of advanced PC patients remains important, delays in treatment initiation due to repeated biopsies, inclusion in a clinical study or transfer to a specialized cancer center appear to be justified in light of the absence of a strong adverse effect of prolonged TTI on prognosis in advanced PC patients.