The cancer panel is the test used in analyzing multiple genes at once for cancer-associated mutations. It utilizes next-generation sequencing (NGS) approaches, such as amplicon sequencing, in targeting specific genes or mutations relevant to the specific cancer phenotypes. NGS technology allows the sequencing of large genomic regions, the large number of samples, high numbers of genes in a single, efficient, and cost-effective assay. It also provides high sensitivity which allows the discovery of rare somatic mutations that have been, mostly, identified as important cancer drivers.
Targeted panels have been developed for detecting hereditary cancer. It can also be used in monitoring somatic changes in progressive cancer, and more importantly in elucidating the landscape of genetic aberrations that occur across multiple cancers. The mentioned information can be used in identifying novel therapeutics or repurposing existing ones. Up to date, researchers have been focusing on producing targeted gene panels for liquid biopsy and circulating tumor DNA (ctDNA) to monitor cancer initiation or relapse, as well as tumor burden and evolution including the treatment resistance onset.
Cancer panel tests can detect not only the targetable drive genes but also mutations that can confer drug resistance. Aside from that, it can be used to detect hypermutation which is expected to be a good biomarker from immune checkpoint inhibitors.
The clinical utility of cancer panel testing includes investigation of the genetic basis for the response of an individual to therapy. This genetic basis may be the signaling pathways associated with a response to specific therapies, deficiency in the DNA double-strand break repair pathway, and a hypermutated phenotype and microsatellite instability. Cancer panel tests can be used to detect cancer at a young age such as colon, renal, or breast cancer. It can also be used in detecting multiple cancers in an individual, either of the same origin or of different origins. Cancer panel can also apply in diagnosing rare cancers such as ovarian or male breast cancer. Lastly, it can be utilized in cases where multiple relatives diagnosed with related cancers on the same side of the family and spanning multiple generations. Some of the methods utilized in this test include deletion/duplication analysis and next-generation sequencing.
Different cancer panels can detect several cancer types. These include, but not limited to, breast, ovarian, gastrointestinal, and colorectal cancer. Among the most widely studied syndrome includes hereditary breast and ovarian cancer (HBOC), as well as the Lynch syndrome. These cancer types are detectable using cancer panels. The associated genes for HBOC are the high-penetrant BRCA1 and BRCA2, while MLH, MSH2, MSH6, and PMS2 for Lynch syndrome are the four mismatch repair genes that confer high-penetrance for colorectal and endometrial cancer onset.
One of the most successful treatment strategies which utilize NGS-based gene panel test is for lung adenocarcinoma. It has been found out that several genes of diagnosed individuals carry targetable driver mutations, such as ROS 1, ALK, and EGFR. Aside from lung adenocarcinoma, another successful treatment strategy that involves precision medicine is anti-human epidermal growth factor receptor 2 (HER2) therapy. This therapy uses trastuzumab and other molecular-targeting drugs for breast cancer patients, specifically those with tumors overexpressing HER2. Also, this therapy can also be used in patients with other solid cancers such as gastric, colorectal, and lung cancer which all involve HER2 overexpression. Several cancer panels are also designed to detect diagnostic, prognostic, and biologic markers, specifically for targeted therapy for pediatric cancers. These include the following cancer types: sarcomas, brain tumors, leukemias, and embryonal tumors.
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