Indeed, there were more CD68-positive interstitial cells than IDO1-positive interstitial cells in RCC tissues (Table 1), but virtually all the IDO1-positive interstitial cells localized to CD68+ areas (Figure 1), suggesting that IDO1 is present in inflammatory cells as well as in tumor and endothelial cells. This evidence concerns the gene IDO1 and renal cell adenocarcinoma.