Crush cytology: an expeditious diagnostic tool for gastrointestinal tract malignancy.

Crush cytology is a simple and rapid method used for diagnosis of central nervous system lesions. We have evaluated the diagnostic accuracy of crush cytology for gastrointestinal tract lesions.  This was a prospective, cross-sectional, single center study, conducted on the patients who had suspected malignant lesions between August 2018 and March 2020. The crush cytologic diagnoses were correlated with histology to determine the diagnostic accuracy.  During the period of interest, a total of 451 patients (26.4 % esophagus & GE junction, 16.6 % stomach, 5.9 % ampulla & duodenum, and 50.9 % colorectal) had a suspected malignant lesion on endoscopic examination. Histology confirmed 92.9 % cases as malignant lesions and 7.1 % as nonmalignant. On crush cytology, 84.5 % were positive for malignancy, 8.9 % were negative for malignancy and 6.6 % were reported as suspicious for malignancy. The overall sensitivity, specificity, positive predictive value, negative predictive value, and diagnostic accuracy of crush cytology were 97.3 %, 90 %, 99.2 %, 72.5 % and 96.9 %, respectively.  Crush cytology is a highly sensitive, specific, rapid and cost effective technique to diagnose gastrointestinal malignancies in endoscopically suspected malignant lesions. However, it cannot entirely substitute histopathological examination for definite tumor typing, grading, confirming invasion and in cases in which cytology is suspicious. Crush cytology is an added asset to the histology to maximize diagnostic accuracy and accelerating decision making for the management of lesions.