Fine Needle Aspiration (FNA) Doctor/ Interventional Cytopathologist
As a fine needle aspiration (FNA) doctor/ interventional cytopathologist, my work doesn’t end at the bedside. The tiny samples I collect embark on a crucial journey to the cytopathology lab, where precise diagnoses are made. Today, I want to take you on a behind-the-scenes adventure and the mishaps that happen more often than not when doctors do not quite understand the complexities of the laboratory and what makes a diagnosis accurate.
Many types of doctors outside of pathologists perform needle biopsies and make smears themselves. They have been taught (either in residency or by their hospital laboratory) what to do, in general, with a specimen. Most specimens from surgery go into formalin for proper fixation. For cytology specimens, the smears are fixed in alcohol, the gold standard for rapidly preserving the cells. This allows detailed examination under a microscope. However, some smears are left to air dry. Air drying is the method of choice for blood, bone marrow and lymph node smears. And the air dry smear plays a vital role in other situations besides those listed above, including assessing extracellular material and immediate assessment of the biopsy to avoid non-diagnostic results. Let me tell you a story that exemplifies its importance.
Early in my career, I was asked to be an expert witness for a surgery gone wrong. The patient was suing the surgeon, the pathologist and the hospital.
I was asked to interpret the smears from the original fine needle aspiration, blindly, that is without knowing anything other than what the pathologist received and what was on the original requisition slip.
The patient was said to have a mass in the head and neck region. The surgeon performed a fine needle aspiration and sent some material for flow cytometry (a special test to rule out lymphoma) and the rest of the material was spread on slides and fixed in alcohol.
The slides came to the laboratory labeled as such: a mass from the head and neck region. The pathologist who is not a cytopathologist, and who does not regularly see cytological smears, diagnosed the mass as a highly aggressive cancer.
Naturally, she underwent a massive head and neck surgery, which led to disfigurement. When the surgical specimen was analyzed, the diagnosis was not cancer, but rather a benign tumor of the salivary gland: pleomorphic adenoma. Of course the patient was devastated!
What went wrong here? Two things: 1) The surgeon mislabeled the specimen 2) The surgeon submitted only alcohol-fixed smears.
If the surgeon had correctly labeled the specimen as coming from the salivary gland, the pathologist may have taken a step back from diagnosing the mass as an aggressive cancer. Secondly, if at least one smear was air-dried, specific elements that can only be seen on air-dried stains would have been apparent, and the correct diagnosis would surely have been made. Most salivary gland tumors are benign and have a better prognosis than aggressive head and neck cancers.
While alcohol fixation remains the standard for intercellular preservation, air drying offers a distinct advantage by providing information about extracellular material. This material is sometimes pathognomonic for specific tumors of the salivary gland, such as a pleomorphic adenoma.
The Key Difference? Smear Expertise:
Here’s the thing: biopsy doctors, surgeons and cytopathologists all collect samples from tumors, but the way they prepare them for analysis can have a significant impact on the diagnosis. Other specialists are not trained in the nuances of proper biopsy collection, smear technique and preservation. They are trained to do their specialty (eg. surgery). Similarly, an interventional pathologist cannot perform a neck dissection. Cytopathologists, with their specialized training in laboratory medicine, have the understanding and expertise on how and when to prepare both alcohol-fixed and air-dried smears.
The Takeaway:
It is not only how the biopsy is performed, but also how the material is prepared that makes for a better more accurate diagnosis. An interventional cytopathologist has the knowledge and tools for exactly this.
Remember: This blog is for informational purposes only and should not be considered medical advice. Always consult your doctor for personalized recommendations.
Dr. Celina Nadelman is a board-certified FNA specialist in Los Angeles, passionate about patient care and leveraging her expertise to achieve the most accurate diagnoses.
