Can a CT Scan Determine Cancerous Node?
February 12, 2016 10:21 AM   Subscribe

Asking for panicking friend who has had a painful swollen lymph node on one side of her neck for a few weeks. Antibiotics didn't help, so last week she had a CAT scan done and the doctor wants her in today for a follow up.

Can a doctor determine a cancerous versus benign mass with only the CAT scan results? I'm not asking about other tests or anecdotes of CAT scans. Just--is it possible that her doctor could tell just by looking at a CAT scan that the swollen lymph node is cancerous?
posted by yes I said yes I will Yes to Health & Fitness (9 answers total)
 
Best answer: >Just--is it possible that her doctor could tell just by looking at a CAT scan that the swollen lymph node is cancerous?

The general answer here is 'probably not'. It's possible that there could be indicators that arouse suspicion of a cancerous growth, but generally this requires at least a biopsy of the offending tissue.
posted by BrandonW at 10:50 AM on February 12, 2016 [4 favorites]


Best answer: No, that's why they do biopsies when lumps that it's possible to biopsy look suspicious. It could be benign.

So your friend can skip panicking about whether the CAT scan shows cancer, and move on to panicking that they might need a biopsy and that will be positive for cancerous cells. Progress?

Also, it's possible that a CAT scan might be able to rule out cancer, but that's not what you asked and I don't know enough to say.
posted by yohko at 10:52 AM on February 12, 2016 [3 favorites]


It depends on a whole bunch of different factors. I agree with the folks about that the most likely course is that the CT scan will likely only show whether it's potentially suspicious for cancer, and the next step would be biopsy -- generally a Fine Needle Aspiration (FNA) biopsy for this type of thing.

If your friend does have to do a FNA biopsy, you can tell her they're not that bad. The needles are very thin and it's more pressure than pain. It's a very minor in-office procedure.
posted by pie ninja at 11:15 AM on February 12, 2016 [1 favorite]


Best answer: Anecdotal: I'm a metastatic melanoma patient. PET/CT scans show that I have eleven nodules in my lungs that are all suspected to be tumors, but only one of them has been confirmed as malignant since it's the only one that has been biopsied.
posted by ElDiabloConQueso at 11:22 AM on February 12, 2016


Best answer: Cancer is not diagnosed with CAT scans, no. It is diagnosed with a biopsy. The results of a CAT scan may lead a doctor to choose biopsy as the next step.

However biopsies diagnose other things besides cancer, including completely garden-variety stuff like infections, when you need to know specifically what kind of infection. Biopsy is really common for neck lumps because they could be indicative of a really scary dangerous infection that you otherwise wouldn't know you had until things get very bad very fast.

The results of a CAT scan might also rule out any further intervention at this time, simply a wait-and-see situation. Most doctors will still make you come in for a follow-up conversation even if this is the next step, because they want to impress on you how important it is that you go back in pronto if anything changes, and they want to review with you what a "change" is.

Some doctors, though, with this kind of neck lump, are pretty liberal with office surgery to remove them (and then, of course, have them examined by a pathologist for more information).

And it is possible for a doctor to not diagnose cancer but still tell you that they are extremely alarmed by the results of the CAT scan. It's a thing to be prepared to hear, but you should not assume that you absolutely will hear.
posted by Lyn Never at 11:23 AM on February 12, 2016 [2 favorites]


Best answer: If your friend did not have a contrast injection with the CT scan, then the CT scan will only tell the doctor where it is and what structures are around it. This can help narrow down the differential diagnosis and will help the doctor decide whether she needs a biopsy.

If your friend did have a contrast injection, the CT scan will tell the above plus how vascularized it is. This will get you closer to identifying cancerous vs not, but is still unlikely to be definitive.

If the doctor is concerned, they will most likely recommend a biopsy.

I'm sorry. Waiting is the worst. Hang in there.
posted by telepanda at 11:28 AM on February 12, 2016 [2 favorites]


Some CT results can be more suspicious than others for cancer, although a biopsy is the thing that's needed.

I have know 2 people with lumps-->scans-->biopsies who were diagnosed with cat scratch fever, not cancer. I thought it was sort of rare, but I guess not.
posted by SLC Mom at 12:22 PM on February 12, 2016


I notice you've tagged this question with catscratchfever. Has your friend in fact been bitten or scratched recently? Also, how fast did the lump attain its present size? Because if she was bitten or scratched, and then her lymph node suddenly blew up a few days later, that's very likely to be what it is.

I once had to have a supraclavicular lymph node excised after finding out the hard way why reaching into the middle of an active cat fight to pull my assumed-hapless moggy out of harm's way was an ill-considered idea.
posted by flabdablet at 1:10 AM on February 13, 2016


Response by poster: Thanks all. CAT scan showed swollen lymph node that needs to be biopsied via extraction as well as some irregularities on her thyroid; moving now to surgery phase and endocrinologist visit and ultrasound for thyroid.

(This was a case of "my friend..." who is obviously ME; I may as well come clean since I may have more questions in the next few weeks/months.)
posted by yes I said yes I will Yes at 3:48 AM on February 13, 2016 [1 favorite]


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