Breast Screening

False positive results

Each mammogram is read by two specially trained radiologists or film readers, and the woman and her GP usually receive the results within two weeks.

Some women (about 4 in every hundred that are screened) are called back because the x-ray indicates that more tests are needed (NHS Breast Screening Programme – 'Helping you decide' leaflet July 2013). Women should not be surprised if they are called back and then tests show that there is nothing to worry about. Most of these women (3 out of 4) will have no problems and will continue to be screened every three years.

A 'false positive' mammogram is where something found on the x-ray turns out not to be cancer. The radiologist who read the mammogram saw a suspicious change in the breast but further tests found no cancer. These tests can include more mammograms, an ultrasound scan, a fine needle aspiration (FNAC) or a core biopsy (see 'Referral to a breast clinic').

False positives are relatively common in breast screening programmes. They occur more often in younger women, women who have had a breast biopsy or who take hormones, such as oestrogen and progesterone. The skill of the radiologist can also affect the chance of a false positive result.

Some women we spoke with were recalled for further tests after having a routine mammogram on the NHS Breast Screening Programme. These tests showed that they didn't have breast cancer, but being recalled can cause concern. 

She panicked when she was recalled, but a second mammogram showed no breast cancer. she has had...

She panicked when she was recalled, but a second mammogram showed no breast cancer. she has had...

Age at interview: 64
Sex: Female
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Have you ever, throughout the years, had any queries or questions or concerns?

No, I was called back once, oh I don't know how, my husband was still alive, and I had to go back for a second one and that did panic me. But they said they weren't sure whether it was just a normal part of my breast or whether it was unusual. But on looking back they said it was fine and I've been fine ever since. So I've never had to be called back again.

So you had the mammogram and then you had a letter saying?

Saying could I go for another one, and that does give you a slight panic. You think oh dear, you know. And I had to go back for the second one but the letter came back saying it was normal. 

So they just re-took the mammogram? 

Yes, yes. 
 

Mary was shocked when she was recalled. A second mammogram and an ultrasound scan showed there...

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Mary was shocked when she was recalled. A second mammogram and an ultrasound scan showed there...

Age at interview: 72
Sex: Female
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Can you tell me a bit more about what happened this time that you went? Because this time you were actually recalled weren't you?

Yes I was recalled. I had my x-ray done on the fifteenth of October, that was on a Monday and the following Friday I'd a letter from [hospital name] asking me to come back, that they'd made an appointment for me for the following Wednesday and that they couldn't give me a clear, a clearance because it wasn't clear enough for them to do it. And, you know, to come back and if I wished I could take a friend or member of the family and they explained that I would be seen by a nurse and then the doctor. And, if necessary, I would have to have a biopsy and then I wouldn't get the results until, for another week. So I didn't have to have the biopsy because when they did the second, the x-rays at [hospital name], they were clear.

Yes. And were you told that there and then?

Well when the doctor called me in then and as the radiologist came in as well and as I was walking in she said, “They're okay.” So then the doctor examined me and she did an ultrasound and then said, “That's okay.” So the radiologist of course naturally knew what, they know exactly how people are because they're with you while, as you know, doing the x-rays and they know how concerned you are. So she just said, “It's okay.” And that's all she said, like she left the rest naturally to the doctor.

Yeah. So when you received the letter it must have come as quite a shock?

Yes but, it did, it was a big shock, but then again when you're waiting for something you always think 'oh well maybe', especially with that type of check-up.

Yeah. Did it say anything about how many women are recalled every year or?

No they just said a number of, I think that yeah, I think they said, I'm not clear on that now. I can't remember but they did say there was a number of women that there was recalled and everything was, it was just an innocent thing and everything, they got clearance there and then. But this was not a lump as the nurse explained to me, so I wouldn't know anything about it. It was, you know, just white lines and therefore if it was cancer it was just in there, I suppose that in time the breast would show signs of things not being right, which she said I wouldn't find it if I was even checking. I wouldn't know.

Yes. Did she talk to you before you went for the x-ray or afterwards?

No, she was, I was, when I went up, no she, I went into the waiting room as you know and then after a little while the nurse came down and introduced herself and she brought me upstairs and she took me into the cubicle where I had to change and she showed me the x-rays there. She told me, like explained to me why I was brought back.

And what did the doctor talk to you about?

She didn't say very much at all, only asked me, like if I had any, did I notice anything about my breasts and just a general chat really, conversation. And then when she did the ultrasound and she told me it was okay, that I was clear, I had to get dressed. Then I wait to see the nurse again and she talked to me and gave me a leaflet on breast care.

And did she say, “We'll see you again in three years time.”?

Yes. She gave me a card with her phone number on to ring in, like in three years time and of course as she

At the breast clinic, waiting for test results was difficult but Mary was pleased she'd been...

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At the breast clinic, waiting for test results was difficult but Mary was pleased she'd been...

Age at interview: 72
Sex: Female
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So when you received the letter it gave you a date for the appointment?

They'd made an appointment for me, yes.

And how did you feel leading up to that time? Was it something you thought about or it was just something that was at the back of your mind?

What after I got the letter?

After you got the letter.

When I got the letter the first day it was a big, big shock and then there was some days that I thought 'oh I don't think there's anything', you know, I felt, I didn't feel any pain or anything. I know you're not always going to have pain and you then have a problem. But I suppose it was, the worst day was the Wednesday and when I got there, when I got there waiting and had the x-ray done and waiting for the results. That was the, that was worst, like it's just the unknown, not knowing one way or the other. I mean if I'd had a problem I would just have to naturally face it.

And did you take somebody with you?

My husband came up with me, yeah.

Is there anything that could be done to improve the service at all do you think, or you're quite happy with?

Well I'm happy with what I've, the way I've been dealt with, very happy about it, 'cause I felt like they didn't waste any time in calling me back, they made the appointment and for me as well to ring and confirm that I would be there. And I felt, well I have to meet them halfway as well.

So it was all done very quickly?

It was all done very quickly you see 'cause, as I've said before, at the stage that I, if I couldn't keep that appointment it might be four weeks before they could see me. And another thing I liked about it, in the leaflet they said that if it was positive then I would have to go on and see a consultant at the hospital and I could have that at the hospital of my choice, which I was happy about because, like if I came, if it came to that, [hospital name] was my nearest hospital here and I thought that was another good idea. So it gives people a chance to pick their nearest hospital as the one should I go to. So I liked that as well.

One woman said that, when she was recalled, more mammograms were taken at the breast clinic. The x-rays showed changes in her breast tissue which were due to the HRT she had started since her last routine screen. Another woman was recalled and had a fine needle aspiration and a core biopsy. The biopsy suggested that the calcifications on her mammogram were ductal carcinoma in situ (DCIS) but, when she had an operation to remove the affected area of her breast, the tissue was reported as benign (not cancerous). Unfortunately, both these women had pre-cancerous cells detected by their next mammogram. One of these women was later found to have invasive breast cancer.

Her mammograms on recall showed that changes in her breast were due to HRT.

Her mammograms on recall showed that changes in her breast were due to HRT.

Age at interview: 62
Sex: Female
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I'd had one mild scare on the second or third one, and I'd been recalled. I remember going to the breast cancer clinic in the hospital with great nervousness, thinking that I must have been diagnosed with cancer. They had to take more mammograms when I was at the hospital, and that turned out because it was - they detected that the tissue in my breasts had changed quite a bit from the previous one. But that turned out it was because I'd started to take HRT in between the two mammograms, and that had considerably changed the tissue in my breasts, and that's all it was, so that was a great relief.

She was recalled and tests suggested she had DCIS. When the affected area was removed though, the...

She was recalled and tests suggested she had DCIS. When the affected area was removed though, the...

Age at interview: 52
Sex: Female
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So I went out and waited and then they called me back again into the room. No, first of all they called me to a Doctor and the Doctor sat me down and she showed me X-rays and she referred to these little white specks on my x-ray. Now all I could see were white pin pricks on the breast, she said "These denote changes" and, after my questions, she said "until proven otherwise they could be cancer." But she said they only denote changes and it is calcifications of the breast. And she said "I'm going to send you out again to get a needle and then a biopsy and you should be getting your results today of your needle".

And then I went on Friday and I got the second biopsy and that's when she said DCIS definitely, that second one. She did definitely say it when I got the second biopsy results. Yes. And then she gave me the operation date.

And in the operation they would be taking out the DCIS? 

Yes, that's what they were taking out and then they were going to send it to the Pathologist who would tell me if it was cancerous or whatever.

So they sent it off to the Pathologist and then they told you that was all benign?

Yes, they told me it was benign. That was the word they used 'benign' and I thought "Oh great". And the Doctor seemed very happy and we seemed very happy and she said "I won't see you until three months", so I was delighted.

One woman was frightened when she was recalled because her mammogram showed calcium deposits. Although these turned out to be harmless, her experience of having a false positive result made her slightly anxious about subsequent mammograms. Another said she didn't feel anxious about subsequent mammograms and, if she noticed any breast changes before her next appointment, she'd visit her GP. 

Having a false positive result made her slightly anxious about the results of subsequent mammograms.

Having a false positive result made her slightly anxious about the results of subsequent mammograms.

Age at interview: 60
Sex: Female
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After I'd had my first scan, my first screening, I was called back. And that again was just another horrendous shock because I then again realised that I was vulnerable, it could happen to me. 

He [consultant] explained that what they had seen on the x-ray were little, I think he said tea cup shapes or saucer shapes that were in the little shapes that showed up in the ducts and he, they were very concerned because that is where duct cancer or you know minute cancer cells generate. But he was quite confident that they were, it wasn't anything to worry about.

And I think I asked a question, I think I asked about whether it was, would have been anything to do with breast feeding, because it was calcium dots, you know, residue of milk [laughs]. I don't know. I can't remember what I asked, but I remember them being quite good about explaining what it was.

So he told you there and then that "we've found these, but it's nothing to follow up about"? 

Yeah, yeah. 

That you could go home?

Yeah, and to not worry about it, that it was nothing that I should be concerned about. But to come for my next one when it was my time. 

Three years later?

Uh huh. 

And I felt relieved that that was what it was, but then coming away thinking well some people have these calcium deposits and it's a serious matter. So it's always there now, it's always hanging about that something was seen on my screen. This was, I'm 60 now and this was, must have been when I was in my early 50's. So you know each time, each year that goes on I think I might be nearer to something, but touch wood nothing's happened yet.  

Mary will be breast aware between her three-yearly mammograms and, if she has any symptoms, will...

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Mary will be breast aware between her three-yearly mammograms and, if she has any symptoms, will...

Age at interview: 72
Sex: Female
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Some women who have been recalled have said that they worried so much about it that in some ways it put them off going for screening completely, but that hasn't, it hasn't, that's not your view?

No, well I did worry about it naturally, but it wouldn't put me off because I would want to know. You see here I would really want to know if it was, if I didn't follow, go for it and I had any pains or aches I'd think 'oh my goodness, something is wrong there' and I still wouldn't feel 'oh I didn't want to go for the screening'. But I, like I still wanted to know but I still would have the courage to go and find out one way or the other.

So it was all dealt with quickly?

Yes

So now you won't be thinking about it until the next three years?

Yes or I'll just keep an eye and if I see anything, as I said, just go back and check with my doctor and see what he says. And I suppose if I did notice anything, if I had, if I did phone the office they would fit me in again maybe, but if not I could, I could go to my own doctor as well, have a chat with him.

Yes. So between the three years, you'll just keep an eye and...

Just keep an eye, as I say. I will still keep in the back of my head what the nurse said that, if it was just like what they were looking at, I wouldn't know from a lump, but if I had continual pain or maybe soreness or a rash or anything, or maybe swelling, I would definitely, as I say, go to my own doctor and explain to him what, because the nurse is writing to my own doctor to tell them that I was called back and they will give him the results so he would have that on file.

The recall rate in NHS breast screening is carefully monitored in order to keep the number of false positive recalls as low as possible.
 

Last reviewed March 2016.

Last updated March 2016.

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