I’d add the following:
(1) This is not clearly a met. Instead, there’s a chance it is, and a chance it isn’t. Nodules this small rarely are, but of course the odds change in a rectal cancer patient with nodal spread, and the growth does raise questions. And as I mentioned, your onc is doing it right—wait until it grows (or doesn’t). Also, biopsy is usually reserved for 10mm+. It’s nerve-wracking, but there are reasons not to rush treatment. One is that you need to get enough tissue for genomic testing if it is a met. (7mm is I think is about minimum for this.) You asked about genetic differences between mets and primary tumors. You’re right that they can differ. This is why you need to test the nodule if it’s eventually found to be malignant—some 5% respond to immunotherapy. I did this, but my genomic testing was delayed by a communication issue, so I don’t yet know the results.
(2) IF this is a met, SOC is to wedge it out (metasectomy) all other things equal. You will see references to SBRT and other therapies like cryoablation or radiation-frequency ablation, but these are still alternative therapies for alternative situations (bad location, low fitness/performance score, etc.). First choice is VATS wedge resection because it is highly successful at local control and gets you tissue to test. I chose SBRT for my second nodule because it was central and would likely have been a lobectomy (LUL). I and my team wanted to preserve healthy lung tissue in case I end up playing whack-a-mole.
(3) Adjuvant chemo after pulmonary metasectomy is hotly debated. I have seen studies that it increases PFS (progression-free survival) but not OS (overall survival). But that’s not the whole picture, and this is a very subtle issue that you should talk to sophisticated oncologists about. Most generally, chemo delays progression of pulmonary mets but does not eradicate them (thus the surgery). Exceptions occur—Claudine’s DH is one (perhaps a journal article, there! : ) Also, if you can do immunotherapy that will increase your odds if you need systemic therapy (the 5%). Finally, in most cases pulmonary CRC mets (without other disease) are associated with longer survival. That may be material, because there are numerous promising technologies and treatments now in trials that could provide rescue in a few years. But these are questions for down the road.
(4) Next—this is great news—you’re relatively far out from your primary surgery, and nothing else has appeared. This is now termed oligometastasis, and its prognosis is relatively favorable. It’s no guarantee, but a good sign even if this is a met.
(5) Finally, there’s IMO a tricky balance here. Even if you have a met, your immune system is doing a good job of containing it. It would be worth trying to maintain the situation (with local control, of course—e.g. metasectomy). Both standard chemo and some alternative therapies can interfere with the immune system. The bet is with chemo generally that it hurts the cancer more than it hurts you. Here, if it’s an easy wedge, it’s not crazy to simply try to promote immune health and watch and wait. But not necessarily right for you. I would be careful in particular about unproven alternative therapies that might impact immune health. But since chemo is not usually curative with pulmonary mets, the choice is hard there too. That’s part of the reason for a strong second opinion. My only view would be that immune health is key, with or without chemo. I am not currently on chemo, but if something pops up I’m not against it.
These are just my perspectives. Others may have different ones. Happy to try to answer any other questions you may have.
Oh, and no guilt! No reason for it. You’re right on schedule with no mistakes or unhelpful delays so far even if it’s a met.
And now I have to go run three miles. It’s a nice evening : )
7/19: Rectal cancer: Staged IIIA, T2N1M0
approx 4.25 cm, low/mid rectum, mod. well diff.; lung micronodule
8/22 -10/14 4 rounds FOLFOX neoadjuvant, 3 w/Oxiplatin (side effects/reduced 70-75%)
neoadjuvant chemorad 11/19
4 rounds FOLFOX July-August 2020
ncCR 10/20; biopsies neg
TAE 11/20, tumor cells removed
Chest CT 3/30/21 small growth in 2 nodules (3 and 5mm)
VATS 12/8/21 sub-pleural met 7mm.
SBRT nodule 1/22
CT 3/22: Clear
Thoracic CT 5/19/22 Clear
6/20/22 TAE rectal polyp benign