Postby catstaff » Fri Jul 09, 2021 8:47 am
My husband has a met in a similar location. We were also told that chemo and radiation were the only options due to a concentration of blood vessels in the area (against the sacrum).
His primary also did not respond to folfox, but the mets, including the "butt met," seem to be responding to folfiri. At least, they responded extremely well to the first five cycles (confirmed by a CT, not just decreasing CEA). We may have had a setback -- he missed a cycle due to a small bowel obstruction (not caused by cancer) resulting in a CEA increase, and the next cycle they omitted bevacizumab and his CEA increased a bit more. This cycle the bev was a go so we'll have to see what happens to his CEA. That's a digression, my main point was that there was documented shrinkage due to folfiri+bev.
Whether it's local or not doesn't really have any predictive value for response as far as I know. It depends on the specific mutations, the immune system response, probably lots of unknown factors. If it's a true local recurrence it would be genetically similar to the primary, but even the primary can change with time as mutations accumulate. And some tumors that don't respond to folfox respond to folfiri and vice versa, again mostly for unknown reasons.
I am hoping to persuade the oncs to do a mop-up radiation treatment on the larger mets, especially if it looks likely that the lymph nodes are controlled. They may be able to do conventional SBRT safely for him (as you know, avoiding the small intestine is critical) but if not, I am very interested in the proton-beam treatment. In our case they may be reluctant to refer him for that since he has other mets and they tend to have an attitude of "no point in removing one if it doesn't cure". I just fear that the "butt met" will be harder to control long term. But if there's only one met that would not be an issue in your case.
D/H Dx 10/2019 RC age 61
Clinical T4bN2M1a (common iliac and para-aortic lymph nodes)
MSS KRAS G12D
CRT 11/19-1/20 FOLFOX 3/20-7/20
Pelvic exenteration w/LAR 8/20
ypT4bN0Mx G3 0/14 nodes LVI not seen PNI-
CEA 10/19:20, 1/20-11/20:1.6, 4.3, 3.4, 2.7, 2/21:9.0 3/21:18,40 4/21:28,19, 5/21:13.3,8.6
PET 3/21 recurrence in distal nodes, L5 vertebra, pelvis
FOLFIRI+bev 3/21-