case_images: PMC6287667_01
case_images: Representative section of gallbladder mass biopsy.. Notes: H&E stained sections of gallbladder mass biopsy show sheets of neoplastic cell infiltration with focal necrosis (A and B, 4x and 10x, respectively). High magnification micrograph (H&E staining, 40x) of gallbladder biopsy shows large neoplastic cells with abundant clear cytoplasm. (C) Immunohistochemistry staining demonstrates positivity of S100 (D), SOX-10 (E), and HMB45 (F).
case_images: ott-11-8723Fig1.jpg
case_images: PMC6287667_01_ott-11-8723Fig1.jpg
case_images: f1-ott-11-8723
case_images: The specimen was remarkable for high-grade malignant melanoma (Figure 1). Immunohistochemical staining was positive for S100, HMB-45, and SOX-10, supporting the diagnosis of malignant melanoma (Figure 1).
case_images: Computed tomography images of abdomen before and after treatment.. Notes: (A and B) Before treatment: there was extensive intraabdominal lymphadenopathy including right retrocrural lymph node (white arrow in A), and periportal and peripancreatic lymph nodes (red arrow in B). (C and D) After 2 months of targeted therapy with dabrafenib and trametinib, an excellent response was noted with interval decrease of retrocrural (white arrow in C) and peripancreatic lymphadenopathy (red arrow in D). "a" and "b" represent the dimension measurements of the peripancreatic lymph nodes.
case_images: ott-11-8723Fig2.jpg
case_images: PMC6287667_01_ott-11-8723Fig2.jpg
case_images: f2-ott-11-8723
case_images: Computed tomography (CT) revealed thickening of the gallbladder wall with enlarged retrocrural lymph node as well as multiple periportal and peripancreatic lymph nodes (Figure 2). A CT scan after 2 months of targeted therapies showed an interval decrease in size of the gallbladder mass and associated lymphadenopathy (Figure 2). A PET scan after 5 months of treatment showed significant decrease in the metabolic activity and size of the lymphadenopathy (Figure 3, lower panel).
case_images: PET scan before and after 5 months of targeted therapy.. Notes: Upper panel: there is a gallbladder mass with intense FDG activity, consistent with biopsy-proven melanoma. In addition, there are multiple FDG avid nodes scattered in the portocaval, pericaval, caval aortic space, right retrocrural regions, and the left periaortic regions. Lower panel: a PET scan after 5 months of treatment showed significant improvement in the metabolic activity and decrease size of the lymphadenopathy in the peripancreatic, periaortic, pericaval, aortocaval, and right retrocrural regions.. Abbreviations: FDG, fludeoxyglucose; MIP, maximum intensity projection; PET, positron emission tomography; PETAC, PET scan with attenuation correction.
case_images: ott-11-8723Fig3.jpg
case_images: PMC6287667_01_ott-11-8723Fig3.jpg
case_images: f3-ott-11-8723
case_images: A baseline PET scan was obtained prior to the initiation of other therapies and revealed extensive lymph nodular metastasis involving the upper abdomen, the retroperitoneum, and the left supra-clavicular region (Figure 3). A CT scan after 2 months of targeted therapies showed an interval decrease in size of the gallbladder mass and associated lymphadenopathy (Figure 2). A PET scan after 5 months of treatment showed significant decrease in the metabolic activity and size of the lymphadenopathy (Figure 3, lower panel).