Noninvasive detection of microsatellite instability in patients with endometrial cancer

The analysis of mismatch repair proteins in solid tissue is the standard of care (SoC) for the microsatellite instability (MSI) characterization in endometrial cancer (EC). Uterine aspirates (UAs) or circulating-DNA (cfDNA) samples capture the intratumor heterogeneity and provide a more comprehensive and dynamic molecular diagnosis. Thus, MSI analysis by droplet-digital PCR (ddPCR) in UAs and cfDNA can provide a reliable tool to characterize and follow-up the disease. The UAs, paraffin-embedded tumor tissue (FFPE) and longitudinal plasma samples from a cohort of 90 EC patients were analyzed using ddPCR panel and compared to the SoC. A high concordance (96.67%) was obtained between the analysis of MSI markers in UAs and the SoC. Three discordant cases were validated as unstable by ddPCR on FFPE samples. Besides, a good overall concordance (70.27%) was obtained when comparing the performance of the ddPCR assay on UAs and cfDNA in high-risk tumors. Importantly, our results also evidenced the value of MSI analysis to monitor the disease evolution. MSI evaluation in minimally invasive samples shows great accuracy and sensitivity and provides a valuable tool for the molecular characterization and follow-up of endometrial tumors, opening new opportunities for personalized management of EC.

M-TRAP: Safety and performance of metastatic tumor cell trap device in advanced ovarian cancer patients

OBJECTIVE

Despite radical surgery and chemotherapy, most patients with ovarian cancer die due to disease progression. M-Trap is an implantable medical device designed to capture peritoneal disseminated tumor cells with the aim to focalize the disease. This trial analyzed the safety and performance of the device.

METHODS

This first-in-human prospective, multi-center, non-blinded, single-arm study enrolled 23 women with high-grade serous advanced ovarian cancer. After primary or interval debulking surgery, 3 M-Trap devices were placed in the peritoneum of the abdominal cavity. 18-months post-implantation or at disease progression, devices were initially removed by laparoscopy. The primary safety endpoint was freedom from device and procedure-related major adverse events (MAEs) through 6-months post-implantation compared to an historical control. The primary performance endpoint was histopathologic evidence of tumor cells capture.

RESULTS

Only one major adverse event was attributable to the device. 18 women were free of device and procedure related MAEs (78.3%). However, the primary safety endpoint was not achieved (p = 0.131), primarily attributable to the greater surgical complexity of the M-Trap patient population. 62% of recurrent patients demonstrated tumor cell capture in at least one device with a minimal tumor cell infiltration. No other long-term device-related adverse events were reported. The secondary performance endpoint demonstrated a lack of disease focalization.

CONCLUSIONS

The M-Trap technology failed to meet its primary safety objective, although when adjusted for surgical complexity, the study approved it. Likewise, the devices did not demonstrate the anticipated benefits in terms of tumor cell capture and disease focalization in recurrent ovarian cancer.

Genomic Profiling of Uterine Aspirates and cfDNA as an Integrative Liquid Biopsy Strategy in Endometrial Cancer

The incidence and mortality of endometrial cancer (EC) have risen in recent years, hence more precise management is needed. Therefore, we combined different types of liquid biopsies to better characterize the genetic landscape of EC in a non-invasive and dynamic manner. Uterine aspirates (UAs) from 60 patients with EC were obtained during surgery and analyzed by next-generation sequencing (NGS). Blood samples, collected at surgery, were used for cell-free DNA (cfDNA) and circulating tumor cell (CTC) analyses. Finally, personalized therapies were tested in patient-derived xenografts (PDXs) generated from the UAs. NGS analyses revealed the presence of genetic alterations in 93% of the tumors. Circulating tumor DNA (ctDNA) was present in 41.2% of cases, mainly in patients with high-risk tumors, thus indicating a clear association with a more aggressive disease. Accordingly, the results obtained during the post-surgery follow-up indicated the presence of ctDNA in three patients with progressive disease. Moreover, 38.9% of patients were positive for CTCs at surgery. Finally, the efficacy of targeted therapies based on the UA-specific mutational landscape was demonstrated in PDX models. Our study indicates the potential clinical applicability of a personalized strategy based on a combination of different liquid biopsies to characterize and monitor tumor evolution, and to identify targeted therapies.