Cytoplasmic staining of CK7 was observed in 10 (90.9%) of the 11 primary lung acinar adenocarcinoma samples but not in 18 (94.7%) of the 19 lung metastasis of colorectal cancer samples nor in any of the primary colorectal cancer samples (Figure 1D, E, and 1F; Table 1). The gene discussed is KRT7; the disease is acinar lung adenocarcinoma.