case_images: PMC9705978_01
case_images: Lesions of the liver, ureteropelvic calyces, and lymph node change during the second-line treatment of pembrolizumab combined with trastuzumab and third-line treatment of pembrolizumab combined with RC48. (A) The baseline MRI image of the second-line treatment. (B) The image of tumor progression after second-line treatment, and the baseline image of the third-line treatment. The hepatic metastasis in the right posterior upper lobe was significantly enlarged and the other lesions reduced after second-line treatment. (C) The first efficacy evaluation after third-line treatment for 2 months: partial response. All tumor foci are reduced. (D) The image evaluation after third-line treatment for 8 months: partial response.
case_images: fimmu-13-978266-g001.jpg
case_images: PMC9705978_01_fimmu-13-978266-g001.jpg
case_images: f1
case_images: The second-line treatment involved trastuzumab 8 mg/kg loading dose followed by 6 mg/kg Q3W and pembrolizumab 200 mg Q3W from 23 June 2021 ( Figure 1A ). Notably, the hepatic metastasis in the right posterior upper lobe significantly increased in size (6.6 cm x 5 cm), whereas the rest of the metastases of the liver and lymph node were reduced ( Figure 1B ). August 2021. After three cycles of treatment, the first evaluation achieved PR with a significant reduction in metastases in the liver (maximum size of 2.5 cm x 2.4 cm) and abdominal lymph nodes on 29 October 2021 ( Figure 1C ). Imaging reexamined every 2-3 months showed sustained PR ( Figure 1D ).
case_images: The patient's latest PET/CT showed a complete response on 25 August 2022. Several slightly hypodense shadows were seen in the liver parenchyma, none of which showed abnormally high 18F-FDG uptake. No definite signs of residual tumors were seen throughout the body.
case_images: fimmu-13-978266-g002.jpg
case_images: PMC9705978_01_fimmu-13-978266-g002.jpg
case_images: f2
case_images: The report showed no definite signs of the tumor throughout the body, and hepatic lesions with low density showed complete remission of metabolism after anti-tumor treatment ( Figure 2 ).
case_images: Timeline scheme of the major clinical events of the patient.
case_images: fimmu-13-978266-g003.jpg
case_images: PMC9705978_01_fimmu-13-978266-g003.jpg
case_images: f3
case_images: The main treatment steps for the patient are shown in  Figure 3 .