Dataset Information

KRAS, NRAS, and BRAF mutations in plasma cell myeloma at a single Korean institute.

ABSTRACT:

Background

Plasma cell myeloma (PCM) is a genetically heterogeneous disease. The genetic spectrum of PCM has been expanded to mutations such as KRAS, NRAS, and BRAF genes in the RAS-RAF-MAPK pathway. In this study, we have evaluated the frequency of these mutations and their significance, including baseline characteristics and clinical outcomes.

Methods

We explored 50 patients who were newly diagnosed with PCM between 2009 and 2012 at a single Korean institute. Clinical and laboratory parameters were gathered through careful review of medical records. Mutation analysis was carried out using DNA from the bone marrow at the time of diagnosis. Pyrosequencing was performed to detect KRAS G12V, KRAS G13D, and NRAS G61R. BRAF V600E was analyzed by allele-specific real- time PCR. Comparison of clinical and laboratory parameters was carried out according to those mutations.

Results

We identified 14 patients (28%) with activating mutations in the RAS-RAF-MAPK pathway (RAS/RAF mutations): KRAS (N=3), NRAS (N=4), BRAF (N=7), and both KRAS and BRAF (N=1). RAS/RAF mutations were more frequently observed in patients with complex karyotypes and showed poorer progression free survival (PFS). Specifically, the BRAF V600E mutation had a significantly negative impact on median PFS.

Conclusion

We first showed the frequency of RAS/RAF mutations in Korean patients with PCM. Screening of these mutations could be considered as a routine clinical test at the time of diagnosis and follow-up due to their influence on clinical outcome, as well as its potential as a therapeutic target.

SUBMITTER: Kim Y

PROVIDER: S-EPMC7536562 | biostudies-literature | 2020 Sep

REPOSITORIES: biostudies-literature

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Publications

<i>KRAS</i>, <i>NRAS</i>, and <i>BRAF</i> mutations in plasma cell myeloma at a single Korean institute.

Kim Yonggoo Y Park Sung-Soo SS Min Chang-Ki CK Lee Gun Dong GD Son Jungok J Jo Sung Jin SJ Han Eunhee E Han Kyungja K Kim Myungshin M

Blood research 20200901 3

<h4>Background</h4>Plasma cell myeloma (PCM) is a genetically heterogeneous disease. The genetic spectrum of PCM has been expanded to mutations such as <i>KRAS</i>, <i>NRAS</i>, and <i>BRAF</i> genes in the RAS-RAF-MAPK pathway. In this study, we have evaluated the frequency of these mutations and their significance, including baseline characteristics and clinical outcomes.<h4>Methods</h4>We explored 50 patients who were newly diagnosed with PCM between 2009 and 2012 at a single Korean institute ...[more]

PMID: 32989177

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