This week, I was rotating on EV cytology. EV means "extra-vaginal." I always wondered why my group doesn't call it NG (non-gyn) like the rest of the world, so I don't have the word "vagina" in my rotating service. EV cytology is anything other than pap smears. Fluids, fine needle aspirates, ultrasound-guided thyroid biopsies, and CT-guided biopsies.
The only exception is when there is a "stat" pap smear. Stat pap smears don't come up very often - they are usually done in the OR when the surgeon sees a fungating mass on the cervix or something, and wants to confirm cancer prior to his or her surgical removal.
Earlier in the week, the head of cytology came into my office.
"I've got a stat pap. I think I need to explain it to you, it's kind of confusing."
She told me that a patient received a diagnosis of High Grade Squamous Intraepithelial Lesion (HGSIL) a week earlier. All paps these days also get molecular HPV (Human Papillomavirus - that is the virus that causes cervical cancer) testing - the wave of the present and future. The molecular testing for high risk HPV types came back negative. I've been in practice for almost three years now, and that is a first for me. The molecular always backs up our diagnoses. She's got a lot more experience than me, so I asked her, "Has this ever happened before?" She shook her head like she couldn't remember a time, and said, "Not often."
I said, "Do you have the pap there? Why is it stat?"
"The OB referred it to someone else, and the new clinician wants to know why the results don't match up. We, of course, would check this ourselves, but they are already aware of the mismatch and want it resolved quickly."
My first question was, "Who reviewed the original pap?" I didn't want to step on any toes. If it was me who reviewed it, I would want to be in on the problem, and I would want to be part of the solution. I saw the pathologist's name, and looked up at the schedule. He was off this week. Darn it. Oh well, I could fix this without him.
I looked at the pap smear while she was standing there. All of the techs had already reviewed it, and all were on the fence between HGSIL and ASC-H (atypical squamous cells of undetermined significance-cannot rule out a high grade lesion). As I moved the slide up and down on the stage, I immediately saw the problem.
Usually, when we see high grade lesions, it is pretty easy because there is a lot of low grade, raisinoid nuclear change in the background, and there are clumps of ugly, hyperchromatic cells with irregular nuclear borders - classic high grade lesions. Here, I saw a few single cells that I learned in fellowship were called "litigation cells." Easy to miss (and subsequently get slammed with a lawsuit because you've got to pay attention to every cell) - because there is no low grade change in the background, no clumps, just rare single cells with really ugly nuclei.
"OK, I see why he called it high grade. In retrospect, in light of the molecular, we could go back and change it to ASC-H, if the OB wants us to do that to triage the patient for proper treatment and follow-up. But first, let's call the molecular company (we currently send these out) and ask them to repeat the hybridization studies. When you call them, find out how often this happens and if there is an explanation - I know there are some rare strains of high grade HPV that aren't covered in their assay. Let's find out what they are, and if we can test for them."
She agreed, and called me later in the day. "The company is going to repeat the qualitative hybridization assay and also run concurrent quantitative PCR studies, which should be more sensitive. They'll call us with the results."
I worried over calling the clinician. I worried over having to change a colleague's diagnosis. I showed the pap to another cytopathologist, didn't give her any of the history so she wouldn't be biased, and she basically agreed with me and the techs. "I'm on the fence. Could go either way." It was easier for us all to be hedge-y in light of the molecular. Those few cells were darn scary.
The cytotech called me the next day. "PCR came back positive. They think it is a rare high risk strain. The diagnosis stands fine, and we will just release the report to the clinician."
Whew. It feels good to make the right call, so the patient can get the right treatment.