Pancreatic ductal adenocarcinoma (PDAC) is a devastating disease. Circulating tumor cells (CTC) in the blood are hypothesized as the means of systemic tumor spread. Blood obtained from healthy donors and patients with PDAC was therefore subject to size-based CTC-isolation. We additionally compared Kirsten rat sarcoma viral oncogene homolog (KRAS) mutations in pancreatic CTC and corresponding tumors, and evaluated their significance as prognostic markers. Samples from 68 individuals (58 PDAC patients, 10 healthy donors) were analyzed; CTCs were present in patients with UICC stage IA-IV tumors and none of the controls (p < 0.001). Patients with >3 CTC/ml had a trend for worse median overall survival (OS) than patients with 0.3–3 CTC/ml (P = 0.12). Surprisingly, CTCs harbored various KRAS mutations in codon 12 and 13. Patients with a KRAS G12V mutation in their CTC (n = 14) had a trend to better median OS (24.5 months) compared to patients with other (10 months), or no detectable KRAS mutations (8 months; P = 0.04). KRAS mutations in CTC and corresponding tumor were discordant in 11 of 26 “tumor-CTC-pairs” (42%), while 15 (58%) had a matching mutation; survival was similar in both groups (P = 0.36). Genetic characterization, including mutations such as KRAS, may prove useful for prognosis and understanding of tumor biology.

Background: The 5-FU, Leucovorin, Oxaliplatin and Docetaxel (FLOT) protocol provides superior oncologic results compared to other perioperative chemotherapeutic protocols for the treatment of non-metastatic esophagogastric cancer (EGAC). Survival and the pattern of recurrence of EGAC after FLOT and curative tumor resection are analyzed in a collective of patients treated outside clinical trials. Methods: Two-hundred-seventy-seven patients with EGAC (cT3-4 and/or cN+) were treated with perioperative FLOT-chemotherapy plus curative surgery between 2009 and 2018. Data were analyzed retrospectively from a prospective database. Results: Two-hundred-twenty-eight patients were included in the analysis. Postoperative in-hospital mortality was 2%. The median survival was 61–months, and median recurrence-free survival was 42 months. Multivariate analysis identified postoperative nodal status and T-stage as independent predictors of improved overall and recurrence-free survival. Administration of adjuvant chemotherapy failed to be significant for overall survival but was an independent predictor of recurrence-free survival. Recurrence occurred after a median of 9 months (range 1–46 months). Eighty-nine percent of recurrence occurred during the first 24 months. The rate of local recurrence was low. After surgery for gastric cancer, the major recurrence site was peritoneal carcinomatosis (56%), while esophageal cancer recurred mostly as metastasis to distant organs (78%). The specific site of recurrence had no impact on overall survival time. Conclusion: Real-life application of FLOT shows oncologic results comparable to clinical trials. Recurrence after FLOT and surgery for EGAC occurs predominantly early within the first two years after surgery and in the form of distant organ metastasis for esophageal tumors or peritoneal carcinomatosis for gastric tumors.

Background: Isolation of circulating tumor cells (CTC) holds the promise to improve response-prediction and personalization of cancer treatment. In this study, we test a filtration device for CTC isolation in patients with non-metastatic esophageal adenocarcinoma (EAC) within recent multimodal treatment protocols. Methods: Peripheral blood specimens were drawn from EAC patients before and after neoadjuvant chemotherapy (FLOT)/chemoradiation (CROSS) as well as after surgery. Filtration using ScreenCell® devices captured CTC for cytologic analysis. Giemsa-stained specimens were evaluated by a cytopathologist; the cut-off was 1 CTC/specimen (6 mL). Immunohistochemistry with epithelial (pan-CK) and mesenchymal markers (vimentin) was performed. Results: Morphologically diverse malignant CTCs were found in 12/20 patients in at least one blood specimen. CTCs were positive for both vimentin and pan-CK. More patients were CTC positive after neoadjuvant therapy (6/20 vs. 9/15) and CTCs per/ml increased in most of the CTC-positive patients. After surgery, 8/13 patients with available blood specimens were still CTC positive. In clinical follow-up, 5/9 patients who died were CTC-positive. Conclusions: Detection of CTC by filtration within multimodal treatment protocols of non-metastatic EAC is feasible. The rate of CTC positive findings and the quantity of CTCs changes in the course of multimodal neoadjuvant chemoradiation/chemotherapy and surgery.