case_images: PMC8270715_01
case_images: Hematoxylin and eosin staining and immunohistochemical staining of tissue from the renal biopsy in Case 1 (x400).
case_images: CRIU2021-9936330.001.jpg
case_images: PMC8270715_01_CRIU2021-9936330.001.jpg
case_images: fig1
case_images: A biopsy of the left renal mass was performed, and pathological analysis revealed collecting duct carcinoma (CDC) (PAX8+, Vimentin+, and CD10-) (Figure 1).
case_images: Computed tomography (CT) findings in Case 1. Abdominal CT showed no change in the right primary renal tumor or bone metastasis after four cycles of immunotherapy.
case_images: CRIU2021-9936330.002.jpg
case_images: PMC8270715_01_CRIU2021-9936330.002.jpg
case_images: fig2
case_images: After completion of two cycles of the combination immunotherapy, computed tomography (CT) revealed a slight enlargement of the primary tumor and bone metastases but showed no change during the two additional cycles of the combination therapy or the nivolumab monotherapy (Figure 2).
case_images: PMC8270715_02
case_images: Hematoxylin and eosin staining and immunohistochemical staining of tissue from the renal biopsy in Case 2 (x400).
case_images: CRIU2021-9936330.003.jpg
case_images: PMC8270715_02_CRIU2021-9936330.003.jpg
case_images: fig3
case_images: Pathological analysis of a biopsy specimen of the right renal mass revealed CDC (CK19+, PAX8+, and CD10-) (Figure 3).
case_images: Computed tomography (CT) findings in Case 2 showing new lesions in the lung after two cycles of immunotherapy, which shrank following the two additional cycles.
case_images: CRIU2021-9936330.004.jpg
case_images: PMC8270715_02_CRIU2021-9936330.004.jpg
case_images: fig4
case_images: After two additional cycles, all the tumors shrank markedly (Figure 4).