Four decades have passed since palpation-guided fine-needle aspiration (PG-FNA) crossed the Atlantic Ocean from the Karolinska Institute in Stockholm, Sweden and entered the United States. Led by cytopathologist innovators such as Dr. Yolanda Oertel, then at George Washington University Medical Center, pathologists emerged from behind the paraffin curtain to see patients and perform PG-FNA biopsies.1 As a result, the terms “clinical cytopathologist” and “interventional cytopathologist” became part of the pathology lexicon. Adoption of PG-FNA in the United States has been very heterogeneous. At some academic centers and teaching hospitals, such as University of California San Francisco (UCSF), Stanford, and Englewood Hospital in New Jersey, pathologists perform thousands of FNAs each year with excellent results. In other venues, PG-FNA was never adopted, and surgical biopsy remains the standard. Because PG-FNA is minimally invasive and relatively easy to perform, many clinicians started doing PG-FNA with mixed results. PG-FNA is easy to do but sometimes difficult to obtain a diagnostic specimen. Ljung showed that inexperienced aspirators with no formal FNA training had 10 times the false-negative rate of experienced aspirators in PG-FNA diagnosis of palpable breast cancers.2 The false-negatives were overwhelmingly caused by sampling error. In the right hands, PG-FNA is an excellent diagnostic tool. For lack of a better term, this first iteration of minimally invasive tissue diagnosis of palpable masses can be informally called FNA 1.0. In this era of precision medicine, the presence of lesional cells on FNA by itself may not be deemed adequate for its intended purpose.3 For example, architecture may be required for subtyping a tumor, such as invasion in breast cancer or follicular lymphoma in a lymph node. Sufficient lesional cells, not just presence of abnormal cells, must be extracted to provide enough DNA in certain cases for phenotyping and genomic studies. There is a need and opportunity to go beyond FNA 1.0

Over the ensuing 2 decades, diagnostic imaging of all types emerged and accelerated. Screening mammogram became a gold standard of preventive medicine in women over age 40-50 years. Ultrasound became widely available both in hospitals and in small clinical practices. Virtually all hospitals had on-site CT scanners and many had MRI and PET scanners. With the ease of obtaining all types of body imaging, many non-palpable masses were discovered and often as incidental findings. Biopsy of these masses could not be done by PG-FNA and required imaging guidance. As a result, radiologists became leaders in ultrasound-guided fine-needle aspiration (UG-FNA) and CT/MRI-guided biopsies. The quality of these imaging-guided biopsies varied depending on the interest and experience of the radiologist. When an imaging-guided FNA was not diagnostic, the blame game went back and forth between the radiologist and the pathologist. Other specialties started doing UG-FNA in the office because the quality of ultrasound images improved and the price of ultrasound machines dropped. Some pathologists crossed the Rubicon and started doing UG-FNA.4 Pathology specialty societies, such as the College of American Pathologists, American Society for Clinical Pathology, American Society of Cytopathology, and The United States and Canadian Academy of Pathology, started offering CME courses in UG-FNA. The College of American Pathologists offers a Certificate of Special Recognition in Ultrasound-Guided Fine-Needle Aspiration to board certified pathologists who complete their didactic program and pass written and practical examinations.5 How good is pathologist-performed UG-FNA? Wu showed that experienced cytopathologists have a higher sensitivity rate and lower non-diagnostic rate in UG-FNA of thyroid masses than clinicians and radiologists.6 In 2020 at Fine Needle Aspiration Medical Group in Alhambra, CA, 1300 cytopathologist-aspirated UG-FNA were performed on thyroid masses. Most masses were non-palpable. Audit data showed non-diagnostic 1.1%, benign 83.2%, AUS/FLUS 6.9%, SFN 3.8%, SFM 0.8% and malignant 4.1%. In experienced hands, UG-FNA can be a fabulous diagnostic tool. Even in palpable masses, UG-FNA can lead to better smears. The needle can be guided into the most suspicious areas and avoid necrotic, cystic, or hypervascular areas. Needle placement can be documented by printed and saved images. UCSF, Stanford, and Englewood Hospital have adopted UG-FNA for all pathologist-performed needle biopsies.

The question arises who should perform UG-FNA? Inevitably, there are “turf battles” on which specialty should perform UG-FNA. But that is the wrong question. The correct question is, “Who has the experience to successfully perform UG-FNA that will most benefit the patient?” Radiologists no more own the ultrasound machine than pathologists own the microscope, hematology counter, or chemistry analyzer. If a clinician is skilled in UG-FNA, he or she should perform the biopsy in his or her office since the patient is already there. Many endocrinologists do their own thyroid UG-FNA and even examine smears microscopically for adequacy. Dermatologists often interpret their own skin biopsies. Interventional cytopathologists can be available to perform UG-FNA if it is the best option. The focus should be on the helping the patient.