Analysis of pathological specimens from renal cancer patients has shown that the prognosis of patients with low expression of is poorer compared to that of patients with high expression (13). excised specimen showed higher PD-L1 expression in the spindle components than in the tubular components, but CD4- and CD8-positve T-cells showed greater infiltration in the tubular components than the spindle components. Conclusion: Combination immunotherapy of nivolumab and ipilimumab may be an effective treatment option for metastatic MTSCC of the kidney. the same procedure as previously revealed that the tumor cells of the tubular/spindle components were positive for AE1/AE3 (+/+), Epithelial Membrane Antigens (EMA; Leica Biosystems) (+/+), vimentin (Agilent) (+/+), Paired box protein-8 (PAX8; Biocare Medical, Pacheco, CA, USA) (+/+), AMACR (+/+) in the resected specimen after nivolumab plus ipilimumab. EMA, vimentin and PAX8 were revealed using Refine Detection Kit Mixed DAB Refine in BOND-III. Open in a separate window Figure 6 Macroscopic findings. The tumor at the upper pole of left kidney was mostly necrotic with hemorrhaging (black arrow) and white-toned solid parts (black arrowhead). Open in a separate window Figure 7 Excised specimen. Ondansetron HCl (GR 38032F) (A) Ondansetron HCl (GR 38032F) Hematoxylin eosin, tubular components on the right side and spindle components on the left side. Scale bar=500 m. (B) Alcian blue staining. Scale bar=100 m. In addition, the biopsy of the pretreated renal tumor and bone metastasis and the resected specimen after nivolumab plus ipilimumab was evaluated by immunostaining of programmed cell death ligand 1 (PD-L1; Agilent), cytotoxic T lymphocyteCassociated antigen-4 (CTLA-4; Santa Cruz Biotechnology), cluster of differentiation 4 (CD4; Roche Diagnostics), and cluster of differentiation 8 (CD8; Roche Diagnostics) the same procedure as previously. PD-L1 was revealed using PD-L1 IHC 22C3 pharmDX (Dako, Santa Clara, CA, USA) in Autostainer Link 48 (Dako). CTLA4 was revealed using OptiView DAB IHC detection kit (Roche, Basel, Switzerland) in VENTANA BenchMark Has2 ULTRA (Roche). CD4 and CD8 were revealed using UltraView DAB IHC detection kit (Roche) in VENTANA BenchMark ULTRA. The PDL-1 expression was higher in the spindle components compared to the tubular ones, but CD4- and CD8-positve T cells showed greater infiltration in the tubular compared to the spindle components (Figure 8 and Figure 9). Furthermore, CD-4- and CD-8-positive T cells in both components of the resected specimen showed greater infiltration in the pretreatment biopsy of the renal tumor and bone metastases compared to the after-treatment biopsy (Figure Ondansetron HCl (GR 38032F) 3 and Figure 4). There was no marked difference in the CTLA-4 expression between the spindle and tubular components in the resected specimen (Figure 8 and Figure 9). Open in a separate window Figure 8 Tubular components. (A) Hematoxylin Eosin (HE), (B) programmed cell death ligand-1 (PD-L1; brown), (C) cytotoxic T lymphocyteCassociated antigen-4 (CTLA-4; brown); (D) cluster of differentiation 4 (CD4; brown), (E) cluster of differentiation 8 (CD8; brown). Scale bar=200 m. Open in a separate window Figure 9 Spindle components. (A) Hematoxylin Eosin (HE), (B) programmed cell death ligand-1 (PD-L1) brown, (C) cytotoxic T lymphocyteCassociated antigen-4 (CTLA-4; brown), (D) cluster of differentiation 4 (CD4; brown), (E) cluster of differentiation 8 (CD8; brown). Scale bar=200 m. serves a key role as a suppressor gene in the cell cycle, proliferation, differentiation, apoptosis, tumor metastasis and drug resistance (11,12) and has also been reported in renal cell carcinoma (13,14). The nonsense variant S562* from a Serine mutation in the gene was reported using next-generation sequencing with FoundationOne?CDx (Foundation Medicine, Inc.). The tumor mutation burden was 2.52 mutations per megabase, and microsatellite instability was absent. Discussion MTSCC was originally reported as a rare histological type of RCC with a low malignant potential (15,16). Patients with MTSCC of the kidney treated with surgical resection tend to generally have favorable outcomes. However, fatal cases of MTSCC with distant metastases have been reported (3,17-21). No therapeutic strategy has yet been established for metastatic MTSCC, with the efficacy of targeted agents and monotherapy of immune checkpoint inhibitors reported in only a few case reports (3-8). Ondansetron HCl (GR 38032F) Only one case report regarding the combination of nivolumab plus ipilimumab for metastatic MTSCC after cytoreductive nephrectomy has recently been reported, showing some efficacy (9). Ipilimumab.