Histologic features and genomic alterations of primary colorectal adenocarcinoma predict growth patterns of liver metastasis

Figure 1 Representative histological images of the growth pattern of primary colorectal carcinoma and liver metastasis. A: Primary colorectal carcinoma (CRC) with an expanding growth pattern where the tumor gland pushes the surrounding stroma with a sharper dividing interface (arrows show expanding growth pattern); B: Liver metastasis with a desmoplastic growth pattern showing a stroma band separating the tumor with the surrounding liver parenchyma (arrows show desmoplastic growth pattern), the same case as A; C: Primary CRC with an infiltrating growth pattern where streams of tumor cells permeate into the stroma with an irregular interface (arrows show infiltrating growth pattern); D: Liver metastasis with a replacement growth pattern showing tumors cells in direct contact with hepatocytes and grow into the liver cell plate (arrows show replacement growth pattern), the same case as C; E: Negative inflammatory cell band (ICB) negative. There is no lymphocyte infiltration at the tumor-normal tissue interface, as arrows show; F: Low grade ICB. Lymphocyte infiltration is present in less than 50% tumor-normal tissue interface, as arrows show; G: High grade ICB. Lymphocyte infiltration is present in more than 50% tumor-normal tissue interface, as arrows show; H: Positive Crohn’s disease-like response (CDR) showing lymphoid aggregates at the deeper aspects of the bowl wall (arrows show aggregated lymphoid tissue); I: Positive CDR showing lymphoid aggregates at the mucosal-submucosal junction (arrows show aggregated lymphoid tissue).