scholarly journals Circulating tumor DNA to monitor treatment response and detect acquired resistance in patients with metastatic melanoma

Oncotarget ◽  
2015 ◽  
Vol 6 (39) ◽  
pp. 42008-42018 ◽  
Author(s):  
Elin S. Gray ◽  
Helen Rizos ◽  
Anna L. Reid ◽  
Suzanah C. Boyd ◽  
Michelle R. Pereira ◽  
...  
2020 ◽  
Vol 38 (15_suppl) ◽  
pp. e16112-e16112
Author(s):  
De-Shen Wang ◽  
Yu-Hong Li ◽  
Hua Bao ◽  
Xiaoxi Chen ◽  
Ming-Tao Hu ◽  
...  

e16112 Background: BRAF mutations are found in about 10% of colorectal cancer (CRC) patients and is a poor prognosis factor in standard chemotherapy. Combination of BRAF and EGFR inhibition exerts a better therapeutic effective, whereas the resistance develops through undefined mechanisms. Circulating tumor DNA (ctDNA) is a non-invasive approach to assess the genetic evolution of tumors and prognosis in response to therapy, which would help better understanding the treatment response and resistance mechanism in BRAF inhibitor treated colorectal cancer patients. Methods: We performed panel next-generation sequencing of 425 cancer-related genes in 39 serial plasma samples collect from 19 patients who have BRAF V600E mutation CRC to track the resistance during the Vemurafenib treatment in combination with Irinotecan and Cetuximab (VIC) and evaluate the treatment response. Tumor responses were assessed radiologically every two months and are used to determine patients with innate or acquired resistance Results: A total of 19 patients were enrolled into the vemurafenib treatment with irinotecan and cetuximab. By January 20, 2020, treatment had been discontinued in 12 (63.2%) of the patients due to disease progression, while the other 7 cases were still under treatment. Among them, four patients with innate resistance (n = 4, 21.1%) were defined as those with PFS of less than 2 months, while patients (n = 15, 78.9%) with acquired resistance were defined as those with PFS of greater than 2 months. The VIC regimen demonstrated efficacy in patients with BRAF-mutant mCRC, with overall response rates was 63.2% (n = 12). Changes in levels of ctDNA at 4 weeks predicts therapeutic responses. CBLB, TP53 and APC baseline mutations were enriched in baseline samples of innate resistant patients. In contrast, MYC and Cell-cycle pathway alterations were enriched in baseline samples of patients with acquired resistance. Acquired RAS and MAPK mutations, known to confer resistance to BRAF inhibitors, were identified in 60% of acquired resistance patients. Moreover, acquired TGFBR2 and SMAD4 loss-of-function mutations were identified as novel resistant mechanism to the combination of BRAF and EGFR inhibition. Experimental validation is ongoing. Conclusions: Longitudinal analysis of ctDNA in BRAF CRC patients provides insights of molecular difference between innate and acquired resistance and gene alternation during resistance requiring. Serial ctDNA monitoring provides early indication of response to BRAF inhibitor in CRC patients.


2021 ◽  
Vol 39 (6_suppl) ◽  
pp. 25-25
Author(s):  
Hanna Tukachinsky ◽  
Russell Madison ◽  
Jon Chung ◽  
Lucas Dennis ◽  
Bernard Fendler ◽  
...  

25 Background: Comprehensive genomic profiling (CGP) by next-generation sequencing (NGS) of circulating tumor DNA (ctDNA) from plasma provides a minimally invasive method to identify targetable genomic alterations (GAs) and resistance mechanisms in patients with metastatic castration-resistant prostate cancer (mCRPC). The circulating tumor fraction in patients with mCRPC and the clinical validity of GAs detected in plasma remain unknown. We evaluated the landscape of GAs using ctDNA-based CGP and assessed concordance with tissue-based CGP. Methods: Plasma from 3,334 patients with advanced prostate cancer (including 1,674 mCRPC screening samples from the TRITON2/3 trials and 1,660 samples from routine clinical CGP) was analyzed using hybrid-capture-based gene panel NGS assays. Results were compared with CGP of 2,006 metastatic prostate cancer tissue biopsies. Concordance was evaluated in 837 patients with both tissue (archival or contemporaneous) and plasma NGS results. Results: 3,127 patients [94%] had detectable ctDNA. BRCA1/2 were mutated in 295 patients [8.8%]. In concordance analysis, 72/837 [8.6%] patients had BRCA1/2 mutations detected in tissue, 67 [93%] of whom were also identified by ctDNA, and 20 patients were identified using ctDNA but not tissue [23% of all patients identified using ctDNA]. ctDNA detected subclonal BRCA1/2 reversions in 10 of 1,660 [0.6%] routine clinical CGP samples. AR alterations, including amplifications and hotspot mutations, which were detected in 940/2,213 patients [42%]. Rare AR compound mutations, rearrangements, and novel in-frame deletions were identified. Altered pathways included PI3K/AKT/mTOR [14%], WNT/β-catenin [17%], and RAS/RAF/MEK [5%]. Microsatellite instability was detected in 31/2,213 patients [1.4%]. Conclusions: In the largest study of mCRPC plasma samples conducted to date, CGP of ctDNA recapitulated the genomic landscape detected in tissue biopsies, with a high level of agreement in detection of BRCA1/2 alterations. It also identified patients who may have gained somatic BRCA1/2 alterations since archival tissue was collected. ctDNA detected more acquired resistance GAs than tissue, including novel AR-activating variants. The large percentage of patients with rich genomic signal from ctDNA, and the sensitive, specific detection of BRCA1/2 alterations position liquid biopsy as a compelling clinical complement to tissue CGP for patients with mCRPC.


2018 ◽  
Vol 9 (2) ◽  
pp. 210-219 ◽  
Author(s):  
Kevin K. Lin ◽  
Maria I. Harrell ◽  
Amit M. Oza ◽  
Ana Oaknin ◽  
Isabelle Ray-Coquard ◽  
...  

Author(s):  
Mahrukh M. Syeda ◽  
Jennifer M. Wiggins ◽  
Broderick Corless ◽  
Cindy Spittle ◽  
George Karlin-Neumann ◽  
...  

JAMA Oncology ◽  
2018 ◽  
Vol 4 (4) ◽  
pp. e175245 ◽  
Author(s):  
Clara Montagut ◽  
Guillem Argilés ◽  
Fortunato Ciardiello ◽  
Thomas T. Poulsen ◽  
Rodrigo Dienstmann ◽  
...  

2020 ◽  
pp. 222-232 ◽  
Author(s):  
Melanie M. Frigault ◽  
Aleksandra Markovets ◽  
Barrett Nuttall ◽  
Kyoung-Mee Kim ◽  
Se Hoon Park ◽  
...  

PURPOSE Some gastric cancers harbor MET gene amplifications that can be targeted by selective MET inhibitors to achieve tumor responses, but resistance eventually develops. Savolitinib, a selective MET inhibitor, is beneficial for treating patients with MET-driven gastric cancer. Understanding the resistance mechanisms is important for optimizing postfailure treatment options. PATIENTS AND METHODS Here, we identified the mechanisms of acquired resistance to savolitinib in 3 patients with gastric cancer and MET-amplified tumors who showed a clinical response and then cancer progression. Longitudinal circulating tumor DNA (ctDNA) is useful for monitoring resistance during treatment and progression when rebiopsy cannot be performed. RESULTS Using a next-generation sequencing 100-gene panel, we identified the target mechanisms of resistance MET D1228V/N/H and Y1230C mutations or high copy number MET gene amplifications that emerge when resistance to savolitinib develops in patients with MET-amplified gastric cancer. CONCLUSION We demonstrated the utility of ctDNA in gastric cancer and confirmed this approach using baseline tumor tissue or rebiopsy.


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