Ultrasonographic screening for cancer in patients with gallbladder disease using a high-frequency probe: a single center retrospective study

<p>Objective: We performed cancer screening in patients with gallbladder disease (GBD) using a high-frequency probe.</p><p>Methods: Participants were 58 patients with GBD aged 32-79 years (median, 48) showing ultrasonographic abnormalities. The men-to-women ratio was 35:23. Two ultrasonographic probes were used for all patients; a convex probe (Toshiba PVT-375BT [3.5 MHz]) and linear electronic scan probe (PLT-704SBT [7 MHz]). The ultrasonographic console was the Toshiba Aplio 500. Statistical analysis used t-tests or χ² tests, appropriately.</p><p>We categorized ultrasonographic findings in 3.5-MHz and 7-MHz images as 0, uninterpretable; 1, normal; 2, benign; 3, difficult to distinguish; and 4, malignancy suspected. A fifth category addressed clinical judgment (A, no abnormality; B, mild abnormality; C, repeat ultrasonographic examination required; D, medical care required; and E, treatment underway).</p><p>Ultrasonic image findings and assessment categories were based on the revised abdominal ultrasound screening assessment manual (2021). For each patient, ultrasonic images obtained using 7-MHz images were evaluated as 0, poorer; 1, equivalent; 2, better; and 3, much better than that of 3.5-MHz images. The judge is a board certified fellow of the Japan Society of Ultrasonics in Medicine.</p><p>Results: Comparing 3.5-MHz and 7-MHz images respectively showed category 2 (benign), 19% (11 cases) vs. 72% (42 cases); category 3 (difficult to distinguish), 17% (10) vs. 12% (7); and category 4 (malignancy suspected), 64% (37) vs. 16% (9). Category 2 (benign) was more frequent for 7-MHz than that for 3.5-MHz images (P < 0.001). Judgment category C (repeat sonographic examination required) accounted for 26% (15) vs. 79% (46). Judgment category D2 (close follow-up required) accounted for 74% (43) vs. 21% (12); this was significantly less frequent for 7-MHz than that for 3.5-MHz images (P < 0.001). Compared to 3.5-MHz images, 7-MHz image quality was rated as 0 (worse) in two cases; 1 (equivalent) in 15, 2 (better) in 25, and 3 (much better) in 16. In 71% of cases (41 of 58), 7-MHz images were considered better and much better. </p><p>Among patients with GBD definitively diagnosed by ultrasonography, the final diagnosis was gallbladder adenomyomatosis in 45 patients, diffuse gallbladder wall thickening in five patients, and gallbladder polyps in four patients. Among four patients with suspected gallbladder tumors who underwent surgical resection, two confirmed to have cholesterol polyps; one gallbladder adenomyomatosis and one adenoma.</p><p>Conclusion: Using the high-frequency probe, we obtained good-quality ultrasonographic images in patients with GBD, enabling more accurate clinical judgment in abdominal ultrasound for cancer screening.</p>