C‐kit expression by CD117‐positive NK cell subset in patients with non‐small lung cancer, cancer of gallbladder (moderately differentiated), cancer of esophagus (epidermoid type), colorectal cancer (infiltrated and squamous cancer, all with metastasis in lymph nodes or lungs or liver), and sigmoid cancer was strongly decreased irrespective of the differentiation stage and disease severity: 47.5 ± 23.7 (n = 10) in healthy donors versus 1.57 ± 0.67 in patients (n = 12) with cancer (p < 0.001, Fig. 1A). This evidence concerns the gene KIT and esophageal cancer.