Circulating tumor cells as a predictor and prognostic tool for metastatic clear cell renal carcinoma: An immunocytochemistry and genomic analysis.

BACKGROUND: Treatment of metastatic clear cell renal carcinoma (mccRCC) has changed dramatically over the past 20 years, without improvement in the development of biomarkers. Recently, circulating tumor cells (CTCs) have been validated as a prognostic and predictive tool for many solid tumors. OBJECTIVE: We evaluated CTCs in blood samples obtained from patients diagnosed with mccRCC. Comparisons of CTC counts, protein expression profiling, and DNA mutants were made in relation to overall survival and progression-free survival. METHODS: CTCs were isolated from 10 mL blood samples using the ISET® system (Isolation by SizE of Tumor Cells; Rarecells, France) and counted. Protein expression was evaluated in immunocytochemistry assays. DNA mutations were identified with next generation sequencing (NGS). RESULTS: Blood samples (10 mL) were collected from 12 patients with mccRCC before the start of first-line systemic therapy, and again 30 and 60 days after the start of treatment. All 12 patients had CTCs detected at baseline (median, 1.5 CTCs/mL; range: 0.25-7.75). Patients with CTC counts greater than the median had two or more metastatic sites and exhibited worse progression-free survival (19.7 months) compared to those with CTC counts less than the median (31.1 months). Disease progression was observed in 7/12 patients during the study. Five of these patients had baseline CTC counts greater than the median, one had higher CTC levels at the second blood collection, and one patient had CTCs present at 1 CTC/mL which positively stained for PD-L1, N-cadherin, VEGF, and SETD2. CTC DNA from six patients with worse outcomes was subjected to NGS. However, no conclusions could be made due to the low variant allele frequencies. CONCLUSION: Detection of CTCs in patients with mccRCC receiving first-line treatment is a feasible tool with prognostic potential since increased numbers of CTCs were found to be associated with metastasis and disease progression.

HPV virus and biomarkers of resistance to chemoradiation in circulating tumor cells from patients with squamous cell carcinoma of the anus.

Localized anal cancer is mostly represented by squamous cell carcinoma of the anus (SCCA) and is cured in ≥80 % of cases by chemoradiation (CRT). Development of techniques for detection/evaluating circulating tumor cells (CTCs) for diagnosis/ prognosis/response to therapy can change the manner we treat/follow SCCA patients. OBJECTIVE: to detect CTCs from patients with SCCA and evaluate the presence of HPV virus, p16 expression and markers related to resistance to CRT (RAD23B/ ERCC1/ TYMS) in CTCs at baseline and after CRT. METHODS: CTCs were isolated/quantified by ISET®, protein expressions were analyzed by immunocytochemistry and HPV DNA was detected by chromogenic in situ hybridization. RESULTS: We enrolled 15 patients: median age was 61 (43-73) years, the majority was women (10/15). CTCs were detected in all patients at baseline (median= 0.4 (0.4-3.33) CTCs/mL) and in 8/9 patients, after CRT (median= 2.33 (0-7.0) CTCs/mL). DNA from HPV was found in CTCs in 14/15 patients (93.33 %) at baseline and in 7/9 (77.7 %) after treatment. At a median follow-up of 22.20 (1.45-38.55) months, three patients expressed ERCC1 in CTCs after treatment, with one of them having disease recurrence. CONCLUSION: We showed that detection of HPV in CTCs from patients with non-metastatic SCCA is feasible and appears to be a sensitive diagnostic method. These results may be clinically useful for better monitoring these patients. However, future larger cohorts may demonstrate whether there is any correlation between the presence of HPV and the expression of screening markers for CRT in SCCA.