MRCS B practice

A MRCS B station on MedMock, start to finish

This is a MedMock session shown in full: the brief, every word that was said, and the scorecard the marker produced at the end — nothing trimmed, nothing rewritten. The candidate was played by MedMock on one of our own test accounts, not by a real user, and the transcript is here to show what a station is like, not as a model answer. The replies from the patient were generated during the session and the scorecard is the marker’s verbatim output.

The brief

You are the core surgical trainee in the breast clinic. Siobhan Kelleher, a 58-year-old woman, has been diagnosed with invasive breast cancer and is listed for wide local excision with sentinel lymph node biopsy. Your task is to explain the operation and obtain her informed consent.

Information Giving & Consent: the full transcript

Candidate

Good morning, I'm Dr Lin, one of the surgical trainees working with the breast team. Could I just check your full name and date of birth, please? I've been asked to talk you through the operation that's been planned for you and, if you're happy, to go through the consent form together. Before I start, could you tell me what you understand so far about your diagnosis and the operation?

Patient

It's Siobhan Kelleher, and my date of birth is the fifth of March nineteen sixty-eight. I understand there's something that showed up on my mammogram, and they've said it needs to come out. They mentioned doing some kind of operation but I'm not entirely sure what it involves, to be honest. I've had the scans done and they've looked at my lymph nodes under my arm, but I'm a bit nervous about what happens next. I suppose I'm wondering if it's very bad, and whether I'll be able to keep my breast or if they need to take the whole thing.

Candidate

Thank you, Siobhan, and it's completely understandable to feel nervous. Can I just check what the team told you about the biopsy result, so I'm not going over things in a way that doesn't match? My understanding from your notes is that the biopsy showed a breast cancer, and the good news I can give you straight away is that the plan is to keep your breast. The operation is called a wide local excision, which means removing the lump with a rim of healthy tissue around it rather than taking the whole breast. Is it alright if I explain how that works, and then the part about the lymph nodes under your arm?

Patient

Yes, that's good to hear. They did mention the biopsy showed cancer, but hearing you say they can keep the breast is a relief, honestly. I was worried it might be like what happened to my aunt years ago. So yes, please, explain how it works. I want to understand what's going to happen and what it means for me. I suppose I'm still a bit frightened, but I'd rather know the details than sit here guessing.

Candidate

I'm sorry about your aunt; treatment has changed a lot since then, and many women now keep their breast. The operation is done under a general anaesthetic, so you'll be asleep, and most people go home the same day or the next day. If the lump is hard to feel, a small marker or wire is placed beforehand under ultrasound or mammogram guidance so the surgeon knows exactly where to find it. The surgeon then removes the lump with a margin of normal tissue around it, and it goes to the lab so they can check the cancer has been fully removed. Does that part make sense so far?

Patient

Yes, that makes sense. So you put in a marker first so you know where to look, and then you take out the lump with some of the healthy tissue around it. And it goes to the lab to make sure you've got it all out. That's helpful to know. I suppose my main worry now is whether they'll find that it's spread, or whether taking it out like that will be enough. And you mentioned something about the lymph nodes under my arm as well. Is that part of checking whether it's spread?

Candidate

Yes, exactly, that's the purpose of it. Your scan of the armpit didn't show anything obviously wrong, but a scan can't pick up very small amounts of cancer, so we check the first one or few glands that the breast drains to, which we call the sentinel nodes. Before or during the operation a small amount of a weak radioactive tracer, and sometimes a blue dye, is injected into the breast, and that travels to those first glands so the surgeon can find them through a small cut in the armpit. The lump and the glands are looked at under the microscope, and the results are usually discussed by the whole team about two weeks later. If there's no cancer in those glands, that's very reassuring and nothing more is usually needed in the armpit; if there is, we'd talk to you about whether any further treatment there is needed.

Patient

So they inject something radioactive to find the first glands, and then they look at those under a microscope to see if there's anything there. That makes sense. Two weeks sounds like a long time to wait, but I suppose that's when you'll know whether it's just the lump or if it's gone further. That's the bit that worries me most, I think. If it hasn't spread to the glands, does that mean it's not going to come back? And what happens after that, once you've done the operation and the results come back?

Candidate

I'll be honest with you: clear glands are a very good sign, but nobody can promise it will never come back. After this type of operation, most women are offered radiotherapy to the breast, because keeping the breast plus radiotherapy works as well as removing the whole breast. Whether you'd also benefit from hormone tablets or chemotherapy depends on the final results, and the oncologist would go through that with you. Your breast care nurse will be your point of contact during that wait, so you're not left on your own with it. Would it be alright if I now go through the risks of the operation?

Patient

Yes, go on. I'd rather hear what could go wrong so I know what I'm dealing with. Though I have to say, all this talk of radiotherapy and chemotherapy is making my head spin a bit. I didn't expect there'd be so much to it after the operation. But yes, tell me about the risks. I need to know what could happen during the surgery itself, I suppose. And what about my arthritis medication? I take methotrexate for that. Will that cause any problems with the operation?

Candidate

That's a lot to take in, and you'll get it all in writing too. Thank you for mentioning the methotrexate: it's usually continued around this kind of surgery, but please don't stop or change it yourself, and I'll make sure the anaesthetist and your rheumatology team are aware, as it can slightly raise the risk of wound infection. From the breast itself, the common problems are pain, bruising, a collection of fluid or blood that sometimes needs draining, wound infection, and a change in the shape of the breast or a dent under the scar. The most important one to know is that in about one in five women the lab finds cancer cells too close to the edge of what was removed, and a second operation is then needed to take a bit more tissue.

Patient

Right, so there's quite a bit that could happen then. Pain and bruising I can manage, but a collection of fluid sounds a bit worrying. And if they find cancer cells at the edge, that means going back in for another operation? That's not ideal, but I suppose it's better to get it all out properly the first time round if they need to. One in five is quite a lot of women though, isn't it? I'm trying to take it all in. What about the armpit side of things — are there risks from taking out those glands as well?

Candidate

It is a fair number, because the surgeon can't see those tiny cells during the operation, but a second operation is usually smaller and most women still keep their breast. From the armpit, it's common to get numbness on the inside of the upper arm, some shoulder stiffness, or fluid building up there. There's also a small risk of long-term arm swelling called lymphoedema, roughly five in a hundred, which is far lower than if all the glands were removed. If blue dye is used, your urine can turn blue-green for a day or two and the breast skin can stay blue for some months, and very rarely people have a serious allergic reaction, which the anaesthetist is ready to treat. Finally there are the general risks of any anaesthetic and a small risk of blood clots in the legs, which we reduce with stockings and getting you up and moving.

Patient

That's quite a lot to take in, all of that. The numbness and stiffness I can live with, but lymphoedema sounds more serious. I do quite a bit of lifting in my studio work, so that worries me a bit. And the blue dye turning my urine blue-green is strange but I suppose harmless enough. The blood clots concern me though — I've heard about those. You mentioned stockings and moving around, which I can do. So let me ask you this: if I go ahead with this operation, what happens if they do find cancer in those glands under my arm? What would come next for me?

Candidate

If cancer is found in those glands, it depends how much: with only a small amount, many women need nothing more to the armpit, or radiotherapy to the armpit instead of more surgery; if there's more, you might be offered an operation to remove more of the glands, and the team would discuss that with you. On your studio work, you'll get arm and shoulder exercises and advice from the breast care nurses, most women get back to normal activities, and if you ever notice swelling in the arm you'd be seen early. I should also mention the alternatives: removing the whole breast, which doesn't improve survival for a cancer like yours but avoids radiotherapy in most cases, or in some women tablets or chemotherapy before surgery, and you're also entitled to choose not to have treatment, though we'd expect the cancer to grow. Can I check what you've taken from all that, in your own words?

Patient

Right, so if I understand it, you're taking out the lump with some healthy tissue round it, and checking the first glands under my arm with that radioactive tracer. Most likely those glands are fine, and then I'd have radiotherapy on the breast. But if there is cancer in the glands, it depends how much, and you'd talk to me about whether I need more surgery or just radiotherapy instead. I can keep my breast, which is what I want, and I'll get help with exercises so I can get back to my work. The alternative is taking the whole breast out, but you're saying that doesn't change whether it comes back. I think I understand the operation now, but I'm still a bit worried about what happens if those glands show cancer.

Candidate

That's a really clear summary, Siobhan; the one thing I'd add is that survival is the same whichever of those two operations you have. It's completely natural to worry about the glands, and if they do show cancer you won't be told by letter, you'll be seen in clinic with your breast care nurse and we'll make a plan together. I'll give you written information and the breast care nurse's number, and you don't have to sign anything today; you can take time, talk it over with family, and you can change your mind at any point up to the operation. What questions do you have for me?

Patient

I do have a couple of questions, yes. One thing I'm wondering about — and I'm not sure if this is something you can help with — but will this affect me being intimate with my partner? I've only been with him about a year and I suppose I'm worried about how the scar will look, whether he'll... well, whether things will be different. I know that might sound vain at my age, but it matters to me. And also, my daughters are abroad and I haven't told them yet. Should I wait until after the operation, or do you think I should tell them beforehand?

Candidate

That doesn't sound vain at all, it's a really important question. The scar is usually placed so it's as discreet as possible and tends to fade over time, the breast may look a little different in shape, and there's no physical reason to avoid intimacy once the wound has healed; the breast care nurses are very used to talking about body image and relationships, and your partner is welcome to come along. About your daughters, that's entirely your decision, but many women find it helps to have family support before the operation rather than after, and the nurse can help you think about how to tell them. Would you like me to arrange for you to see the breast care nurse today, and we can go through the consent form whenever you feel ready?

Patient

That's really kind of you to say that. Yes, I think I'd like to see the breast care nurse today if that's possible. It helps knowing there's someone I can talk to about all of this without feeling silly. And you're right about my daughters — I think I should tell them before the operation rather than leaving it until after. I'm just nervous about how they'll react, but I'd rather they heard it from me. So yes, let's go ahead with the consent form when you're ready. I feel a bit better now that I understand what's happening, even though it's still quite a lot to take in.

Candidate

I'm really glad it feels clearer. On the form I'll write the operation in plain words, a wide local excision and sentinel node biopsy, and could you tell me which breast it is so we can confirm the side together? I'll list the risks we've talked about, you'll get your own copy, the surgeon will check it with you again and mark the side on the day, and you can still change your mind at any point. You'll also have a pre-assessment appointment where the methotrexate will be checked, and if anything worries you before then, please ring the breast care nurse. I'll go and arrange for her to see you now; thank you, Siobhan, you've asked really good questions.

Patient

It's the left breast. That's where they found the thickening behind the nipple. Thank you for going through all of this so carefully with me. I feel like I understand what's happening now, even if it's still quite scary. I'm glad I'll see the breast care nurse today and get the written information. And I'll definitely ring if anything comes up before the pre-assessment. I think I'm ready to sign the form whenever you are.

Candidate

Thank you, so that's the left breast. Because the area is just behind the nipple, there's one more thing you need to know: the surgeon may need to remove tissue very close to, or sometimes including, the nipple, which could change how it looks or feels. Before you sign, I'd like the consultant to go through exactly what's planned for the nipple with you, so you're making the decision with all the facts. I'll bring the form and the written information with the breast care nurse, and we'll finish it together; thank you, Siobhan.

Patient

Right, so the nipple might need to come out or change how it looks. I hadn't thought about that, to be honest. That's... well, that does matter to me, I suppose. I'm glad you're saying the consultant will go through exactly what they're planning before I sign anything. I need to know what that means for how it will look afterwards, especially given what I just said about my partner. So yes, I'll wait and speak to the consultant about the nipple specifically before I sign. Thank you for making sure I know all of this.

The scorecard

90 / 100

Clinical knowledge and its application8 / 10

Demonstrated strong knowledge of WLE, SLNB risks, and adjuvant radiotherapy equivalence, but missed the specific SLNB false-negative rate and exact UK margin standard.

Clinical and technical skill9 / 10

Structured the risk consultation well (breast vs armpit vs general) and correctly noted that methotrexate can increase wound infection risk while appropriately involving pre-assessment.

Communication10 / 10

Exemplary communication using the Calgary-Cambridge framework, effectively employing teach-back, signposting, and open questions to explore ideas, concerns, and expectations.

Professionalism9 / 10

Maintained patient autonomy by stressing she could change her mind, involved the breast care nurse immediately, and ensured fully informed consent regarding the nipple.

What went well

  • Clear, chunked explanation of complex dual procedures (WLE and SLNB) with an excellent teach-back request ('Can I check what you've taken from all that').
  • Appropriately recognised the tumour location (behind the nipple) upon confirming the side and correctly deferred final consent pending a consultant discussion about nipple excision.
  • Handled the patient's concern about intimacy and body image with empathy and validated it effectively ('That doesn't sound vain at all, it's a really important question').

What to improve

  • Did not explicitly quantify the false-negative rate of sentinel lymph node biopsy (typically 5-10%).
  • Did not state the specific UK margin clearance standard for the lab check (no tumour on ink for invasive disease).

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