Finding the Familiar Face
I'm walking through the crowded hospital lobby holding a portion of someone's brain spread out on a slide. It's hidden in a cardboard folder designed to hold slides, to hold pieces of people's bodies as they are transported; from the lab to the microscope; from the microscope to to be filed in the slide library; and when pathologists take the slides themselves, carrying them through a crowded lobby in January. I'm covering intraoperative frozen sections this morning, and there's an intimidating neurosurgeon* performing a brain biopsy. The patient, a man in his 30's, is someone who previously had a brain tumor and now there's something new, something potentially concerning on follow up imaging. This young man is fortunate in that it took two years for his brain tumor to grow back, but that's what the team is worried about. So, early this morning the surgeon drilled a hole in the young man's skull, carefully matched up the location on the image to his instruments, and extracted a small portion of soft white and red tissue, about the size of a thumbtack. The surgeon is standing there in the OR that is cool and quiet, in his magnetized MRI suite, wearing small microscopic eyeglasses that he looks over to no doubt scrutinize the clock while he awaits my answer. This neurosurgeon doesn't like any equivocating, which I can't blame him for, and seems to not like anyone other than the neuropathologist to tell him about his biopsies. He also requires personal delivery of the results, to his masked face in the OR, all of which heightens an already high tension, high stakes situation. I've never seen a high grade brain tumor I didn't love. But that's the problem. It's why am I walking the slide to my colleague, said neuropathologist, who is working across the street, so that I can get his input. It's because under the microscope I don't see what I expected to see - I don't see a tumor. Instead I see the cells surrounding any problem in the brain; we call them reactive astrocytes. While beautiful, they are not what I want to see, and I am filled with doubt - could I be missing a subtle atypia, some cellular change that indicates a low grade tumor? Telling a neurosurgeon that the biopsy is Non Diagnostic is about the worst thing one could tell a neurosurgeon - if you're right, he still has to go back and remove more; if you're wrong, he may remove more tissue unnecessarily. Removing part of someone's brain, no matter how small, is a big deal, as vital blood-filled vessels course over, around and through areas of tumor. For brain biopsy frozen section analysis we do not like to actually freeze the brain; this leads to all sorts of confusing distortions in this uniquely fatty tissue. Instead, we prefer the squash prep method. By which fancy term we mean literally squashing a tiny portion of the brain about the size of this letter (O) between two glass slides, dragging the tissue across the slide to hope it sheds cells, and then examining it after fixation and staining.
Squash preps spread out like a comet on the slides and each tumor has a predictable pattern of distribution. We focus at the edges of the cellular clumps to see the individual cell appearance. Here is where we have a chance of going into the origins of that first symptom, the headache, or slur. Making the diagnosis can be amazingly easy – too many cells, too prominent a nucleus, too many irregularities in cell outlines and sizes – clearly a brain tumor. "High Grade Glioma", I can feel confident saying into the loudspeaker in the neurosurgical suite. Seeing a high grade brain tumor brings sweet relief; I’ve identified a long-lost friend, an ally in a crowd of strangers. The relief is serious, because if couldn’t find my friend, I’d be in a lot of trouble, alone, in despair, and in hostile territory. Which is why I am going to find my colleague, the neuropathologist - I need a friend. We can deliver the bad news to the surgeon together: it's normal.
*This may be redundant.