Perioperative bevacizumab improves survival following lung metastasectomy for colorectal cancer in patients harbouring v-Ki-ras2 Kirsten rat sarcoma viral oncogene homologue exon 2 codon 12 mutations†.

OBJECTIVES: The role of perioperative chemotherapy (POC) and targeted therapies in lung metastasectomy for colorectal cancer (CRC) is still subject to debate. We aimed to evaluate whether POC and targeted therapies were associated with different outcomes according to the mutational status.

METHODS: We reviewed data from 223 patients who underwent pulmonary metastasectomy for CRC from 1998 to 2015 and for whom the V-Ki-ras2 Kirsten sarcoma viral oncogene homologue (KRAS) and V-raf Murine sarcoma viral oncogene homologue B1 (BRAF) mutational statuses were known.

RESULTS: A total of 167 patients (74%) underwent POC: 62 (37%) received neoadjuvant therapy, 59 (35%) were in the adjuvant setting and 46 (28%) were in both the neoadjuvant and adjuvant settings. POC did not significantly influence either the loco-regional recurrence free survival (LRRFS) (P = 0.21) or the overall survival (OS) (P = 0.29). Furthermore, in cases of adjuvant chemotherapy, outcomes were not significantly different in cases of neoadjuvant chemotherapy or both neoadjuvant and adjuvant treatment (P = 0.26 for OS, P = 0.14 for LRRFS). For patients with KRAS mutation, perioperative bevacizumab was associated with a significant improvement in both LRRFS [70 months (41.58–98.42) vs 24 months (1.15–46.86), P = 0.001] and OS [101 vs 55 months (49.77–60.23), P = 0.004]. However, this benefit was only significant in cases of KRAS exon 2 codon 12 mutations [median OS: 101 months (83.97–118.02) vs 60 months (53–66.99), P < 0.001; median LRRFS: 76 months (64.62–87.38) vs 44 months (35.27–52.73), P < 0.001].

CONCLUSION: Perioperative bevacizumab appears to be beneficial in patients with exon 2 codon 12 KRAS mutations who have undergone lung metastasectomy for CRC.