case_images: PMC11116784_01
case_images: Magnetic resonance imaging (MRI) detected a tumor in the gastric sinus (as indicated by the red arrow, intersecting surface (A, B); coronal position (C)).
case_images: fonc-14-1321149-g001.jpg
case_images: PMC11116784_01_fonc-14-1321149-g001.jpg
case_images: f1
case_images: The upper abdomen enhanced MRI showed a space-occupying lesion of the gastric sinus, suspicious lymph node enlargement on the lateral side of the greater curvature of the gastric sinus, and a scan of the pregnant uterus ( Figures 1A-C ). Electron fiberoptic gastroscopy revealed a large, ulcerated lesion of the gastric sinus, involving the four walls and the gastric angle, and the lesser curvature of the gastric body ( Supplementary Figure S1 ).
case_images: Immunohistochemistry: Pathological picture of the tumor confirmed under a x40 microscope (A), PD-L1 (-, interstitial 5%) (B), mismatch repair protein expression: MLH1 (-) (C), PMS2 (-) (D), MSH2 (+) (E), and MSH6 (+) (F).
case_images: fonc-14-1321149-g002.jpg
case_images: PMC11116784_01_fonc-14-1321149-g002.jpg
case_images: f2
case_images: The immunohistochemistry results were as follows: CEA (+), P16 (++), Ki67 (80%), P53 (-), ER (-), PR (-), HER2 (-), PD-L1 (-, interstitial 5%), MLH1 (-), PMS2 (-), MSH2 (+), and MSH6 (+) ( Figures 2A-F ). The PET-CT results similarly confirmed this result ( Supplementary Figure S2 ).
case_images: CT enhancement of the abdomen showed tumor recurrence (A), after receiving pembrolizumab therapy (B).
case_images: fonc-14-1321149-g003.jpg
case_images: PMC11116784_01_fonc-14-1321149-g003.jpg
case_images: f3
case_images: CT enhancement of the abdomen showed a soft tissue mass measuring approximately 7.5 cm x 5.2 cm, considered as tumor recurrence/metastasis with a possible involvement of the duodenal stump, pancreatic head capsule, and adjacent transverse colon mesentery, with enlarged lymph nodes in the hilar region and retroperitoneum ( Figure 3A ). During the follow-up, the corresponding tumor markers showed a gradual downward trend ( Supplementary Figure S3 ).
case_images: Timeline of treatment and diagnostic assessment about the patient who received a pembrolizumab injection of 100 mg, intravenous drip regularly. Magnetic resonance imaging (MRI) and enhanced computed tomography (CT) showed the lesion shrinking gradually (A-D).
case_images: fonc-14-1321149-g004.jpg
case_images: PMC11116784_01_fonc-14-1321149-g004.jpg
case_images: f4
case_images: October 8, 2019, MRI enhancement of the abdomen suggested that the soft tissue mass in the right upper abdomen measured approximately 6.5 cm x 4.0 cm ( Figure 4A ). On October 19, 2019, the patient received a pembrolizumab injection of 100 mg intravenous drip for the third time. The duodenum and peripancreatic head lesion was smaller than 19-10-8, multiple lymph nodes in the mesentery, hilar region, and retroperitoneum ( Figure 4B ). During the period November 11, 2019-February 24, 2020, the patient received a pembrolizumab injection of 100 mg intravenous drip regularly, and the lesion had shrunk to 1.7 cm in diameter ( Figure 4C ). At subsequent follow-up, the whole abdomen CTA (August 23, 2021) suggested that the duodenal and peripancreatic head lesion reduced to 0.6 cm, with a bilateral ovarian pattern in full view and multiple lymph nodes in the mesentery, hilar region, and retroperitoneum ( Figure 4D ).