A week ago I noticed a swelling half way up my forearm. It felt about the size of pea under the skin and was painless but hard. It's deep under the skin, not just under the surface and was fixed not mobile.
It is growing rapidly and within 1 week it has almost doubled to the size of a marble. It is NOT soft, fatty like a lipoma, not liquidy like a cyst and it is not close to the wrist like a ganglion (I have had one of those removed from my wrist as a child). It is very hard.
It is painless although if I poke at it hard it can be slightly tender. Although initially immobile, as it has grown I am able to move it slightly.
Obviously worried I went to see my GP yesterday, expecting to be referred for biopsy. The GP's I usually see were unavailable and so I saw a very mature retired female doctor who was filling in as the surgery was low on staff.
She felt it and diagnosed a harmless cyst and told me to see how it goes, but that if it keeps growing to go back in 2 weeks. I was unhappy with this and told her that although she is probably right, I still have concerns that due to the rapid growth and solid appearance that there could be a possibility of it being a soft tissue sarcoma, and didn't really want to wait 2 weeks before referral. She said there was no need to remove it or a biopsy at this stage, and to come back in 2 weeks if i was worried. I explained that I was too worried to wait that long so as a compromise she offered to refer me for an ultrasound, but said she would write on it 'urgent' although explained it could still take a while for me to be called.
She has obviously been practising for many years and I am not questioning her judgement about it being a cyst, and she will probably be right in the end, however I don't agree with her "just leave it and see what happens" approach, and think I should at least be sent for a biopsy.
I suppose the reason I am unhappy about leaving it is that my mother in law was told this when she had medical problems, 8 months later she died from cancer because by the time they did refer her it was too late.
My questions are:
1) Is it possible to firmly diagnose it as a cyst without doing a biopsy?
2) My understanding is that ultrasounds cannot determine whether a lump is malignant or not, only a biopsy can do this, am I right?
3) Doesn't the NHS have some guidelines in place when presented with lumps like this? I thought that a fast growing, hard lump should be referred as urgent, is this correct?.
4) What sort of cyst can it be to grow so quickly?
5) Should I phone my surgery and ask for a second opinion?
Many thanks for your advice :-)