DS7 Pea Size Lump on Collarbone (pic included)

[Louisa1980s]

My 7yo son had a tiny lump appear a few weeks ago. We took him to the gp who referred him for a scan at hospital.
The sonographer told my husband it was a fluid filled lump and no concern but to keep an eye on it.
Drs confirmed the following week no further action.
However it seems to be growing and I'm worried about it.. it's completely hard. Painless. But I've read that if it was a lymphnode its a cause for concern if it's growing. Would the sonographer have known if it was a lymphnode?
Particularly bothered tonight as hes gone to bed crying with terrible pain behind his right knee. Assuming its growing pains but hes never had them before :(

Not an expert but I think they’d literally be able to see that it was fluid filled on an ultra sound? Fluid would clearly show up as a different colour (black)?

Google is telling me this:

Ultrasound can help differentiate between a fluid-filled lump and a lymph node by examining their ultrasound characteristics. Fluid-filled lumps, like cysts, typically appear anechoic (black) on ultrasound due to their lack of internal echoes, while lymph nodes show a more complex pattern with a hypoechoic (darker) cortex and a hyperechoic (brighter) hilum, often with visible blood flow.

The sonographer will be really experienced, but before the final report is signed off it is also reviewed by a registrar or consultant so it’s unlikely both of them are wrong. If it’s growing and causing issues (rubbing on clothes for example), they may remove it.

I had this as a child but on the back of my hand! It felt like hard grissle lump and it woukd get irritaed if knocked. It hung around for a while and then slowly disappeared. I was around age 9/10

The pain in the legs i used to get and I would cey in pain. I thought every child went theough it but I was told no that is not normal. I would cry and my dad would try to help with deep heat but that did nothing. And i suffered for yeaaaars.
Fast forward to age 29 and I did a provate health screaning and found out my Vit D was dangerously low below 20 and nearly 0 ! My potassium was also dangerously low. The symptoms matched with mine. Deep bone pain in the long bones! After I started high dose Vit D 10,000 IU I felt better and all symptoms went away. I stopped getting sick often and my Vit D levels were healthy and above average. No more bone pains!!!!!

I would soeak to the Gp about the leg pain and get his vitmains and Iron and calcium checked.

Ive just come on to post about this again and forgot I did a few months ago! Back to the GP today... DS now has swollen lymphnodes in his groin, armpit, neck and a large swelling on the back of his knee. I only went to ask about the knee swelling, GP noted all the lymphnodes.
She asked us to come back in 2 weeks to recheck. Can't help but feel we are being fobbed off a little. Feels like this has been going on for months 😔

Collarbone lump is still there but growing. GP made aware and checked that too, reiterated the scan said it didn't appear sinister

Hi OP, how worrying for you. You are doing exactly the right thing by getting everything checked - Im not medical so no advice. I hope all re-checks are ok and it’s nothing to worry about. My son has very large lymph nodes, but he was a skinny-ish child so they were more noticeable. He had one on his collarbone that was very obvious, but the GP wasnt concerned and Im not sure if it’s still there! Hes filled out a lot as he’s got older so they aren’t as noticeable now - is your son quite slim? With the swelling on the back of his knee, has he injured it at all? Have they done bloods?

You are right to get them rechecked but some people get these lumps, I get lumps all over the place, again was just worried but they are not dangerous, just annoying

To update again... DS has been referred for an ultrasound on his leg which is a week tomorrow. But today the swollen nodes in his neck are so visible and I'm really stressing again :( does anyone know if this is normal?

He has still never had bloods taken which kind of blows my mind

I had verrry swollen lymph nodes in my neck when I had glandular fever as a teenager. So much that my GP thought it was mumps. After that, for literally years, any infection made my lymph nodes swell like crazy and become painful.

I think you are right to chase the NHS about this, but I hope it's some comfort that these things CAN be benign.