Abstract
We present the case of a 53-year-old male with metastatic rectal cancer who was treatment resistant to FOLFOX and FOLFOXIRI. Due to a Kirsten rat sarcoma viral oncogene homolog (KRAS) mutation, regorafenib was given in the third line setting. Surprisingly, the patient had a prolonged partial response that lasted 27 months. Mutational status was extensively evaluated to identify potential alterations that might play a role as predictive markers for this unusual event. A poorly characterized but nontransforming mutation in Fms-like tyrosine kinase 4 (FLT4) was present in the tumor. Prior to and at the time of clinical progression, we found amplification of fibroblast growth factor receptor 1 (FGFR1) and epidermal growth factor receptor (EGFR), loss of the FLT4 mutation, and gain of KIT proto-oncogene receptor tyrosine kinase (KIT) G961S suggesting potential roles in acquired resistance.
Original language | English (US) |
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Pages (from-to) | 57882-57888 |
Number of pages | 7 |
Journal | Oncotarget |
Volume | 8 |
Issue number | 34 |
DOIs | |
State | Published - 2017 |
Externally published | Yes |
Keywords
- Biomarker
- Metastatic colorectal cancer
- Regorafenib
- Response
- Survival
ASJC Scopus subject areas
- Oncology