534P - Second-line treatment in older patients with metastatic colorectal cancer: The ELECTRA study

Background

An increasing number of older metastic colorectal cancer (mCRC) patients (pts) receive different regimens in II line based on chemotherapy combined or not with biologics treatment (Tdx2) to prolong survival and/or palliate symptoms. Since these pts have been under-represented in clinical trials, the optimal approach and treatment plan should be better defined. The present study aimed to provide a picture of attitudes and clinical practice in the management of older mCRC pts after first-line progression.

Methods

We retrospectively analyzed mCRC older patient’s candidate to receive Tdx2 for metastatic disease in 14 Italian Centers. Prediction of II-line progression-free survival (PFS2) was performed with long-rank test.

Results

Overall, 1678 older patients were analyzed; of them, only 942 (60%) were eligible to receive Tdx2. Notably, 448 (50%) were KRAS muted, 42 (5%) NRAS mut, 65 (8%) BRAF muted and 33 (7%) dMMR. At median follow-up of 67 months, mPFS2 was 8.12 months (6.38 months for mono-CT, 11,97 months for mono-CT plus biologic, 6.58 months for doublet and 9.73 for doublet plus biologic, P<.0001) and median OS from Tdx2 was 13.9 months. Treatment strategies were analyzed and described regrouping patients in three main subgroups (Tab 1). Of note, determinant for deciding intensity of regimen in II line treatment was first-line treatment received (P<.0001). Interestingly, half of them (53%) received subsequent lines of therapy; in particular, 33% received regorafenib, 36% TAS-102 and 19% received a treatment rechallenge.

Conclusions

Second-line chemotherapy for older mCRC patients with mCRC showed clinically meaningful outcomes. Notably, our study enhances our understanding of oncology practice outside of the clinical trial setting and provides useful information for future research and clinical practice in second- and later-line of mCRC patients. Table: 534P

Second-line treatment according to age categories

Clinical trial identification

Editorial acknowledgement

Legal entity responsible for the study

The authors.

Funding

Has not received any funding.

Disclosure

F. Morano: Financial Interests, Personal, Invited Speaker: Servier, Pierre Fabre, Lilly; Financial Interests, Institutional, Research Grant: Incyte. S. Lonardi: Financial Interests, Personal, Advisory Board: Amgen, merck serono, lilly, Servier, AstraZeneca, MSD, Incyte, Daiichi-Sankyo, Bristol-Myers Squibb, Astellas, GSK, Takeda, Bayer, Rottapharm; Financial Interests, Personal, Invited Speaker: Pierre-Fabre, GSK, Roche, Servier, Amgen, Bristol-Myers Squibb, Incyte, Lilly, Merck Serono, MSD, AstraZeneca; Financial Interests, Institutional, Coordinating PI: Amgen, Merck Serono, Bayer, Roche, Lilly, AstraZeneca, Bristol Myers Squibb; Non-Financial Interests, Member of Board of Directors, Italian No-Profit Oncology Research Foundation supporting academic Clinical trials: GONO Foundation. All other authors have declared no conflicts of interest.