Correlation of Endosonographic Elastography with Histopathological Findings in Solid Pancreatic Masses and Comparison with Normal Pancreatic Elastography

Background: Pancreatic cancer prevalence in India is rising, necessitating accurate diagnostic methods. Endoscopic ultrasound-guided fine needle aspiration (EUS-FNA) aids in tissue acquisition, but its sensitivity is moderate. Elastography, measuring tissue elasticity, can enhance diagnosis. However, Indian data on tissue elastography for solid pancreatic masses and its correlation with histopathology are lacking.

Aims:

Study strain ratio's correlation with pancreatic mass histopathology.

Analyze malignancy grade based on strain ratio.

To find strain ratio value of normal pancreas.

Methods: Prospective study at Max Nanavati Hospital, starting October 2022. Inclusion criteria: patients with pancreatic mass. For normal pancreas elastography patient in whom EUS was done for nonpancreatic cause and pancreas was normal on cross-sectional imaging. Exclusion criteria: pregnancy, anticoagulant use, INR >1.5, unfit for anesthesia. EUS done for pancreatic mass, strain ratio calculated and biopsies obtained using a 22 G Acquire needle. Elastography values determined at 3 locations, i.e., head body and tail in normal pancreas average of three taken.

Results: Total of 33 patients with pancreatic masses and 11 for normal elastography evaluated. Mean strain ratio: nonmalignant masses (5.5), malignant (26.4), and normal pancreas (3.37). Lowest neoplastic mass strain ratio: 6.5.

Conclusions: We present first Indian data on strain ratio in patients for pancreatic masses. Neoplastic nature of the pancreatic mass can be considered with more certainty if the strain ratio of mass is >20. This helps in situation when the histological report is equivocal and surgery is being considered. Conservative management may be considered in background chronic pancreatitis with low elastography values. No correlation found between strain ratio and histological grade/type. Small sample size data for normal pancreas elastography suggest mean strain ratio as 3.5 to be normal.

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