This happened to me yesterday. I'm in my last year of med school and am spending a month in an outpatient internal medicine clinic working with "Dr. Jones."
Dr. Jones told me that the next patient, a 75 year old lady named "Mrs. Smith," was undergoing chemotherapy for a really early grade lymphoma. Not a big deal. Nowadays it's a chronic disease... you'll die with the lymphoma, not from it. Anyway, Mrs. Smith was presenting with a cough that was unrelated to her lymphoma. I went in to see Mrs. Smith.
"So Mrs. Smith, how long have you had this cough? any other symptoms? You coughing up anything?" etc. Then I say "So I understand you just finished chemotherapy. Is that correct?"
"and that was for...?"
"that was for...?"
"that was for a lymphoma. Correct?"
"wait. I have lymphoma?"
"um, yes. I was under the impression that you have a low grade lymphoma. Is that correct?"
"I have lymphoma?? I have lymphoma? are you saying I have lymphoma??"
"Well, you have a blood-based neoplasia. Is that correct?
A lymphoma. Or a leukemia."
"I have leukemia??! What are you saying?? Oh no!!"
"well, I must be mistaken. Don't worry, I'll talk to the doctor about this and we'll square things out. Anyway, about your cough..."
I was in a panic. How could this woman not know that she had a lymphoma? She was undergoing chemotherapy for something. She had to know what it was, right? Maybe she was in denial and never actually heard the words lymphoma. I was so nervous. I was sweating bullets. I rushed through a throat and lung exam and ran back into Dr. Jones' office.
"Dr. Jones, you're gonna kill me. I told Mrs. Smith she has a lymphoma and she said 'I have a lymphoma??'"
She responds, "oh, well, we'll figure that out."
So we go into the room together. Dr. Jones sits down next to Mrs. Smith, puts her hand on her shoulder, looks her in the eye and says, "Mrs. Smith, you know you have a lymphoma, right?"
"Yeah, I do. I was just messing around with your med student."