Utility of EUS-Guided FNAC in the Diagnosis of Spindle Cell Lesion of the GI Tract: A Case Report

ABSTRACT Gastrointestinal (GI) tumors pose a diagnostic challenge due to their diverse histology and location. EUS was first used clinically in 1980. Since its inception, it has emerged as a valuable diagnostic tool for GI lesions, to a versatile therapeutic modality, encompassing a wide range of indications. EUS faces challenges in distinguishing benign from malignant lesions. The partnership between cytopathologists and endoscopists, coupled with rapid on-site evaluation (ROSE), has become crucial in patient management. Recent technical advancements along with the addition of FNAC have greatly increased its diagnostic accuracy. Endoscopic ultrasonography-guided fine-needle aspiration cytology (EUS-FNAC) has become a routine practice in many healthcare facilities, aiding in the diagnosis of mediastinal, GI, and pancreatic malignancies. EUS-FNAC offers several advantages, such as multi-site aspiration and lower cost as compared to other procedures. Even its potential in the area of molecular studies has been recently investigated. In this case study, a 45-year-old man who underwent EUS-FNAC is presented. The combination of histology, immunohistochemistry, and EUS-FNAC allowed us to make a conclusive diagnosis of GI stromal tumors (GIST).