Postby Rock_Robster » Fri Feb 18, 2022 8:07 pm
Congrats and thanks for the update!
I found this on Signatera testing for CRC for stages I-III.
“After resection, 80% of patients with detectable ctDNA experienced disease recurrence, as compared with 13% of patients with undetectable ctDNA, translating to a significant 11-fold increase in the risk for relapse (P < .0001). Similarly, after the completion of adjuvant chemotherapy, 83% of patients with detectable ctDNA relapsed, as compared with 12% of patients with undetectable ctDNA (P < .0001). This translated into a 12-fold increase in the risk for relapse”.
I’m not sure if I’m doing bad science and dodgy maths here by mixing candidate pools (actually I’m pretty sure I am), but I believe recurrence rates for stage III overall (including 3b, 3c etc) are in the order of around 30%. So with a negative ctDNA test you could argue your recurrence risk has dropped to 12-13%. Of course as a stage III patient you’re probably on the higher end of the risk spectrum anyway in Signatera test pool, but as a IIIa patient you’d be on the lower end of the stage III recurrence risk stats.
I think all that we can really conclude is that a negative test result is a very encouraging sign, and your recurrence risk is probably relatively low in the scheme of cancers. Unfortunately population median data isn’t much help in predicting individual outcomes. Of course you’re an experiment of 1 and hence the outcome is binary - either you will recur or you won’t, but if you were a horse and we were at the track I’d definitely be putting my money on you.
Best of luck!
Rob
Last edited by
Rock_Robster on Sat Feb 19, 2022 6:16 pm, edited 1 time in total.
41M Australia
2018 Dx RC
G2 EMVI LVI, 4 liver mets
pT3N1aM1a Stage IVa MSS NRAS G13R
CEA 14>2>32>16>19>30>140>70
11/18 FOLFOX
3/19 Liver resection
5/19 Pelvic IMRT
7/19 ULAR
8/19 Liver met
8/19 FOLFOX, FOLFOXIRI, FOLFIRI
12/19 Liver resection
NED 2 years
11/21 Liver met, PALN, lung nodules
3/22 PVE, lymphadenectomy, liver SBRT
10/22 PALN SBRT
11/22 Liver mets, peri nodule. Xeloda+Bev
4/23 XELIRI+Bev
9/23 ATRIUM trial
12/23 Modified FOLFIRI+Bev
3/24 VAXINIA (CF33 + hNIS) trial