A universal cell-free DNA approach for response prediction to preoperative chemoradiation in rectal cancer.

The standard treatment approach for stage II/III rectal cancer is neoadjuvant chemoradiation therapy (nCRT) followed by surgery. In recent years, new treatment approaches have led to higher rates of complete tumor eradication combined with organ-preservation strategies. However, better tools are still needed to personalize therapy for the individual patient. In this prospective observational study, we analyzed colon-derived cell-free (cf)DNA (c-cfDNA) using a tissue-specific DNA methylation signature, and its association with therapy outcomes. Analyzing plasma samples (n = 303) collected during nCRT from 37 patients with locally advanced rectal cancer (LARC), we identified colon-specific methylation markers that discriminated healthy individuals from patients with untreated LARC (area under the curve, 0.81; 95% confidence interval, 0.70-0.92; P < .0001). Baseline c-cfDNA predicted tumor response, with increased levels linked to larger residual cancer. c-cfDNA measured after the first week of therapy identified patients with maximal response and complete cancer eradication, who had significantly lower c-cfDNA compared with those who had residual disease (8.6 vs 57.7 average copies/ml, respectively; P = .013). Increased c-cfDNA after 1 week of therapy was also associated with disease recurrence. Methylation-based liquid biopsy can predict nCRT outcomes and facilitate patient selection for escalation and de-escalation strategies.

First Female Patient with a Rare CIC-FOXO4-Translocated Sarcoma: A Case Report.

Small round cell sarcoma is a group of undifferentiated malignancies arising in the bone and soft tissue, notable for Ewing sarcoma. Recently, a new World Health Organization classification has been introduced, including an additional subset of these sarcomas, named CIC-rearranged sarcoma. Within this group, CIC-FOXO4 translocation is an exceedingly rare fusion that has been reported only 4 times in the literature. Herein, we report in-depth the pathological, clinical, and molecular features of a CIC-FOXO4 translocation-driven tumor in a 46-year-old woman.

Liquid biopsy reveals collateral tissue damage in cancer.

Cancer inflicts damage to surrounding normal tissues, which can culminate in fatal organ failure. Here, we demonstrate that cell death in organs affected by cancer can be detected by tissue-specific methylation patterns of circulating cell-free DNA (cfDNA). We detected elevated levels of hepatocyte-derived cfDNA in the plasma of patients with liver metastases originating from different primary tumors, compared with cancer patients without liver metastases. In addition, patients with localized pancreatic or colon cancer showed elevated hepatocyte cfDNA, suggesting liver damage inflicted by micrometastatic disease, by primary pancreatic tumor pressing the bile duct, or by a systemic response to the primary tumor. We also identified elevated neuron-, oligodendrocyte-, and astrocyte-derived cfDNA in a subpopulation of patients with brain metastases compared with cancer patients without brain metastasis. Cell type-specific cfDNA methylation markers enabled the identification of collateral tissue damage in cancer, revealing the presence of metastases in specific locations and potentially assisting in early cancer detection.

Life and death of circulating cell-free DNA.

Tumor-specific, circulating cell-free DNA in liquid biopsies is a promising source of biomarkers for minimally invasive serial monitoring of treatment responses in cancer management. We will review the current understanding of the origin of circulating cell-free DNA and different forms of DNA release (including various types of cell death and active secretion processes) and clearance routes. The dynamics of extracellular DNA in blood during therapy and the role of circulating DNA in pathophysiological processes (tumor-associated inflammation, NETosis, and pre-metastatic niche development) provide insights into the mechanisms that contribute to tumor development and metastases formation. Better knowledge of circulating tumor-specific cell-free DNA could facilitate the development of new therapeutic and diagnostic options for cancer management.