Improved detection of circulating tumor cells in non-metastatic high-risk prostate cancer patients.

The relevance of blood-based assays to monitor minimal residual disease (MRD) in non-metastatic prostate cancer (PCa) remains unclear. Proving that clinically relevant circulating tumor cells (CTCs) can be detected with available technologies could address this. This study aimed to improve CTC detection in non-metastatic PCa patients by combining three independent CTC assays: the CellSearch system, an in vivo CellCollector and the EPISPOT. Peripheral blood samples from high-risk PCa patients were screened for CTCs before and three months after radical prostatectomy (RP). Combining the results of both time points, CTCs were detected in 37%, 54.9% and 58.7% of patients using CellSearch, CellCollector and EPISPOT, respectively. The cumulative positivity rate of the three CTC assays was 81.3% (87/107) with 21.5% (23/107) of patients harboring ≥5 CTCs/7.5 ml blood. Matched pair analysis of 30 blood samples taken before and after surgery indicated a significant decrease in CTCs captured by the CellCollector from 66% before RP to 34% after therapy (p = 0.031). CTC detection by EPISPOT before RP significantly correlated with PSA serum values (p < 0.0001) and clinical tumor stage (p = 0.04), while the other assays showed no significant correlations. In conclusion, CTC-based liquid biopsies have the potential to monitor MRD in patients with non-metastatic prostate cancer.

Prognostic impact of perineural, blood and lymph vessel invasion for esophageal cancer.

BACKGROUND: With a median survival of ⟨22 months esophageal cancer is one of the most aggressive tumors, up to 20% of node negative patients develop systemic relapse. Studies investigating the prognostic impact of tumor-micro-invasion in blood (AI) and lymphatic vessels (LVI) as well as perineural invasion (PNI) have shown inconsistent results. The aim of the present study was to investigate the prognostic value of the aforementioned factors in a large homogenously treated cohort of patients with esophageal cancer. METHODS: Data from 695 patients with surgically treated esophageal cancer were analyzed. AI, LVI and PNI were determined and data were statistically correlated with clinico-pathological parameters and survival of the patients. RESULTS: Thirteen percent of all specimens showed an AI, 35% a LVI and 5% a PNI. The invasion factors were mostly significantly correlated with the established prognostic parameter, including bone marrow micro-metastases. Kaplan-Meier analysis revealed a prognostic impact for LVI in both cancer subtypes, while AI and PNI were significant factors in adenocarcinoma only. In multivariate analysis, none showed statistical significance. However, sub-analysis of completely resected, node negative and non-metastasized patients showed a significant prognostic impact of LVI. CONCLUSION: The prognostic significance of AI, LVI and PNI seems to be limited compared to the established prognostic parameters of the UICC staging system. In completely resected, node negative and non-metastasized patients, LVI is an independent prognostic parameter for a worse outcome. Those patients might benfit from additional treatment or more intensive follow up.