Test Details: Immunohistochemical testing is carried out on biopsy/resected tissue specimen. This testing helps to identify specific antigens (proteins) within tissue sections utilizing an antigen-specific antibody IHC arginase 1 is a sensitive and specific marker of benign and malignant hepatocytes. This IHC is used to differentiate between liver cell carcinoma from metastatic carcinoma. IHC arginase 1 is positive in cholangiocarcinoma and few cases of pancreatic adenocarcinoma.