I am a 62 year old female diagnosed with colon cancer (adenocarcinoma) on 9 Sep 2017 and had an emergency right hemicolectemy due to intestinal blockage.
I am RAS wild, BRAF V600E positive, MSSI high with TMB of 42. I had Foundation One testing done on my tumor in March 2018.
I progressed after a first line chemo series of 6 rounds FOLFOX and Vectabix, and again after a second line therapy of 6 rounds of Opdivo with new nodules and groups each time.
In mid-May, I started the VIC (cetuximab, irinotecan and vemurafenib) regime from Dr Scott Kopetz's SWOG 1406 trial and after 5 cycles saw partial response with no new growth, shrinkage and several nodule groups that just disappeared. On Cycle 9, we reduced to 160 mg/m2 of irinotecan and vemurafenib 740 mg PO 2x to manage diarrhea. My last PET scan on 30 Oct after Cycle 12 showed NED, yeah! Vemurafenib is a BRAF inhibitor and it is an off label use for colon cancer - not yet FDA approved but updated in the NCCN guidelines as an approved 2nd or 3rd line of treatment for BRAF V600E based on results from the Stage II trial. The disease control rate was 67%.
Based on discussions with my oncologist, we are continuing maintenance with 8 cycles with full cetuximab and a reduced dose of 125 mg/m2 of irinotecan, vemurafenib 740 mg PO 2x and will do another PET scan at the end of February. I'm managing side effects of mild to moderate fatigue, moderate to severe diarrhea, and potassium, magnesium and fluid loss. Questions I'm researching are:
1. Is there any data on maintenance protocols being considered for this treatment regime? It is still ongoing in the Phase II trial so this is new kind of new ground.
2. Based on the potential over time for activating mutations in MEK or NRAS and prime resistance to MAPK inhibition resulting in activation of downstream ERK signaling, are there any monitoring tests for this? Is FoundationOne Liquid or other ctDNA liquid biopsies of any use?
So after a terrifying first year, I'm cautiously encouraged by the last 5 months. I do VIC Cycle 18 on Monday. I'll update progress as appropriate and would be happy to answer questions if anyone has them.
F, 62, CC
9/11/17: Right hemicolectemy, Stage IVB, Asc adenocarcinoma 7.5x6 cm, T4N2M2, G3, 19/38 LN +, peri mets
RAS wild, BRAF V600E, MSI High, TMB High, loss of exp MLH1/PMS2
10/17-1/18: 6 cyc FOLFOX+Vectabix; 1/18/18 PET progression/new nodules
1/25/1-4/25/18: 6 cyc Opdivo, 4/16 PET showed progression/2 new nodule groups
5/14/18-10/30/18: 12 cyc CIV (Cetuximab, Irinotecan, Vemurafenib); 7/17/18 CT no progression, some nodule shrinkage
10/30/17 PET NED, maint chemo C/70% I/75% V