Diagnosis of Pancreatic Tumors: How Much Does the Triple Diagnosis Method Help?

Summary: Introduction: Differentiating benign from malignant pancreatic lesions can be challenging. While the specificity of the cytological interpretation can reach up to 100%, the sensitivity ranges between 50-80%, mainly due to difficulty in obtaining an adequate sample. Therefore, it should be analyzed in correlation with radiological and clinical impression/endoscopic ultrasound (EUS) to create a diagnostic triplet. The accuracy of ""Triple Diagnosis"" in characterizing pancreatic lesions remains unknown. Materials and Methods: An electronic record search for pancreatic fine needle aspirates (FNAs) was performed at the University of Missouri between January 2019 and December 2022. Chart review was performed for imaging and EUS impression followed by cytologic diagnosis and, where available, correlated with surgical pathology diagnosis. Results: A total of 161 pancreatic FNAs were identified. Of these, 92 (57%) were diagnosed as benign, 50 (31%) malignant, 15 (9%) suspicious for malignancy, and 4 (2.5%) atypical without further characterization. Imaging and EUS were performed for all 161 cases (100%). Due to the lack of a definitive EUS or imaging diagnosis, only 70 (43.5%) cases constructed definitive ""Triplets."" Of these ""Triplets,"" 53 (33%) were benign, and 17 (11%) were malignant. Only a handful of surgical specimens were available for histopathological correlation, two for benign and three for malignant ""Triplets,"" limiting the ability to map out the histological concordance. The malignant ""Triplets"" had 100% concordance between radiology and FNA diagnosis (17/17), while 94% (16/17) concordance with EUS. In contrast, there was 75% concordance in benign ""Triplets"" (40/53) among the three modalities. Conclusions: A surgical specimen is not always available for histopathologic assessment of pancreatic cancers. A combination of radiology, endoscopy, and cytology is highly accurate in predicting the benign versus malignant nature of pancreatic lesions, reaching up to ~100% in malignant cases. A clear and comprehensive impression of all three modalities will increase diagnostic accuracy.