The immunohistochemical staining results were categorized into three groups: ASS1 loss (absence of ASS1 protein expression in tumor cells), low ASS1 expression (less than 10% of tumor cells with ASS1 expression), and positive ASS1 expression (more than 10% of tumor cells ASS1 positive) (Figure 1A–C). The gene discussed is ASS1; the disease is neoplasm.