case_images: PMC11664618_01
case_images: Abdominal contrast-enhanced computed tomography scan reveals a 7 cm mass in liver segments IVb and V, with localized thickening of the gallbladder fundus wall and early-stage enhancement followed by a prolonged contrast effect. A: Arterial phase showed inhomogeneous lesion enhancement; B: The portal venous phase showed a prolonged contrast effect in the mass; C: The delayed phase showed progressive enhancement of the mass; D: The mass invades liver segments IVb and V.
case_images: 100757-g001.jpg
case_images: PMC11664618_02_100757-g001.jpg
case_images: F1
case_images: No pancreatic enlargement or bile duct dilatation was observed (Figure 1).
case_images: Preoperative magnetic resonance imaging examination of the reported case. A and B: The gallbladder lesion appears slightly hyperintense on T2-weighted imaging (A) and hyperintense on diffusion-weighted imaging (B).
case_images: 100757-g002.jpg
case_images: PMC11664618_02_100757-g002.jpg
case_images: F2
case_images: Dynamic contrast-enhanced MRI showed a 6.7 cm mass with low T1 and high T2 signal intensities, along with diffusion-weighted imaging findings (Figure 2).
case_images: Illustration of the surgical procedure. A: A radical cholecystectomy was performed; B: The gross tumor specimen was displayed; C: Macroscopic analysis revealed a greyish-yellow globular lesion; D: Multiple yellowish stones were identified.
case_images: 100757-g003.jpg
case_images: PMC11664618_01_100757-g003.jpg
case_images: F3
case_images: A 6 cm x 7 cm greyish-yellow globular lesion, largely occupied by multiple yellow stones, was macroscopically identified at the gallbladder fundus (Figure 3).
case_images: Pathological analysis results. A: Hematoxylin and eosin staining revealed a nest-like arrangement of tumor cells exhibiting marked cellular heterogeneity and visible necrosis; B-D: Immunohistochemical analyses showed positivity for chromogranin A, Ki-67, and synaptophysin, respectively.
case_images: 100757-g004.jpg
case_images: PMC11664618_01_100757-g004.jpg
case_images: F4
case_images: Notably, the mitotic count was 24 per 10 high-power fields, along with a Ki-67 index of 70%, indicating a poorly differentiated NEC (Figure 4).
case_images: PD-L1 and tumor mutation burden. A and B: Targeted gene sequencing revealed no expression of PD-L1 in gallbladder neuroendocrine carcinoma cells; C and D: Buffer solutions and isotype-matched monoclonal antibodies were used as controls to confirm the specificity of primary antibody binding; E: Targeted gene sequencing also helped quantify the tumor mutation burden. TMB: Tumor mutation burden.
case_images: 100757-g005.jpg
case_images: PMC11664618_01_100757-g005.jpg
case_images: F5
case_images: Additionally, the tumor proportion score and combined positivity score were calculated to assess the immunohistochemical expression of PD-L1, as depicted in Figure 5.
case_images: PMC11664618_02
case_images: Abdominal contrast-enhanced computed tomography scan reveals a 7 cm mass in liver segments IVb and V, with localized thickening of the gallbladder fundus wall and early-stage enhancement followed by a prolonged contrast effect. A: Arterial phase showed inhomogeneous lesion enhancement; B: The portal venous phase showed a prolonged contrast effect in the mass; C: The delayed phase showed progressive enhancement of the mass; D: The mass invades liver segments IVb and V.
case_images: 100757-g001.jpg
case_images: PMC11664618_02_100757-g001.jpg
case_images: F1
case_images: No pancreatic enlargement or bile duct dilatation was observed (Figure 1).
case_images: Preoperative magnetic resonance imaging examination of the reported case. A and B: The gallbladder lesion appears slightly hyperintense on T2-weighted imaging (A) and hyperintense on diffusion-weighted imaging (B).
case_images: 100757-g002.jpg
case_images: PMC11664618_02_100757-g002.jpg
case_images: F2
case_images: Dynamic contrast-enhanced MRI showed a 6.7 cm mass with low T1 and high T2 signal intensities, along with diffusion-weighted imaging findings (Figure 2).