Abstract 98P
Background
Anti-EGFR therapy with cetuximab/panitumumab is administered as a companion drug with fluorouracil based chemotherapy every 2 weeks continuously until disease progression in patients with metastatic colon cancer (mCRC) with wild type (wt) RAS/BRAF mutations. Emerging data suggest better outcomes with intermittent treatment (planned 4-8 weeks break every 6 cycles).
Methods
This is a retrospective study of patients at our institution with inoperable wt mCRC treated with combination chemotherapy and an anti-EGFR antibody until disease progression. Patients received a planned 4-8 week break after every 6 cycles. Log rank univariate analysis was used for comparisons and Kaplan Meier curves constructed for progression free survival (PFS) and overall survival (OS). Outcomes were compared with the historic controls from results published in randomized control trials.
Results
During the study period between June 2016 to June 2022, 113 patients met the inclusion criteria and were analysed. The majority were male (71.7%). Median age was 60 years and 80.5% had left sided disease. The liver was the most common site of metastases followed by the lungs. The commonest regimen used was FOLFIRI + panitumumab (83.2%). Of all patients, 8.8% achieved complete response and 72.6% had a partial response. After a median follow up of 28 months, the median PFS and OS was 20 months and 33 months.
Conclusions
Intermittent anti-EGFR therapy in combination with chemotherapy appears to have better PFS and almost equal OS in comparison to outcomes reported for patients treated with continuous treatment in published trials. This approach warrants further analysis with prospective randomized control trials.
Legal entity responsible for the study
The authors.
Funding
Has not received any funding.
Disclosure
All authors have declared no conflicts of interest.