Role of Pathologist in the Era of Image-Guided and EUS-Guided Aspirations: A 10-Year Study at a Single Tertiary Care Oncology Institute in North India

Abstract

Background: With improved and readily accessible imaging techniques, the shift in fine-needle aspiration cytology (FNAC) from palpation-guided FNA (PGFNA) to image-guided FNA (IGFNA) and endoscopic ultrasound-guided FNA (EUS-FNA) became evident in last few decades. The present study evaluates the impact of IGFNA and EUS-FNA on the practice of cytopathology at our 300-bedded oncology institute.

Study design: A 10-year audit of three aspiration modalities PGFNA, IGFNA, and EUS-FNA was done. The number of aspirates, inadequacy rates, new patient registration numbers, and tissue biopsy numbers were compared.

Results: A total of 29,610 FNAC were evaluated against a total 141,333 new patient registrations over a period of 10 years. The new cancer patient registration over last 10 years showed a 56% increase, with a comparable increase of 60% in diagnostic biopsies; whereas, the number of FNAC increased by only 6%. This reduction in the number of aspirates was mainly due to fall in the number of PGFNA to 18% of all procedures in the year of 2019 from a high of 44% in 2011. Further, PGFNA showed a reduction by 50% over 3 years. The inadequacy rates of PGFNA increased to 9.1% (in 2019) from 1.6% (in 2012). The IGFNA constituted 46%-60% of procedures, with inadequacy varying from 8.5% to 12.1% over years. The EUS-FNAC gradually increased from 3% to 22% from 2013, and the inadequacy rates were variable overtime showing parallelism with the use of rapid on-site adequacy evaluation (ROSE) by the endoscopist. Inadequacy rates ranged from 7.1% (2013) to 2.6% (2016), 7.7% (2017), and 5.4% (2019).

Conclusion: The utility of ROSE and diminishing role of pathologist is highlighted in our study. Judicious ROSE improves diagnostic accuracy, decreases the rate of missed diagnosis and the repetition of procedures. The study sheds light on the ever-increasing lacuna in the training of pathologists for blind as well as in image-guided FNAC. Further, it enumerates the factors leading to the underutilization of ROSE, its undisputed advantages, operator variations in procedure, smear preparation, and screening.

Keywords: Endoscopic ultrasound-guided fine-needle aspiration; Fine-needle aspiration; Image-guided aspiration; Rapid on-site evaluation.