Identification of a high‐risk subtype of intestinal‐type Japanese gastric cancer by quantitative measurement of the luminal tumor proportion

• Published in: Cancer medicine (Malden, MA) MA), 2018-10, Vol.7 (10), p.4914-4923
• Main Authors: Aoyama, Toru, Hutchins, Gordon, Arai, Tomio, Sakamaki, Kentaro, Miyagi, Yohei, Tsuburaya, Akira, Ogata, Takashi, Oshima, Takashi, Earle, Sophie, Yoshikawa, Takaki, Grabsch, Heike I.
• Format: Article
• Language: English
• Subjects: Adult; Aged; Aged, 80 and over; CD45 antigen; Clinical Cancer Research; Digestive System Surgical Procedures; Female; Gastric cancer; Humans; Immunohistochemistry; intestinal‐type; Intestine; Intestines - pathology; Japan; Leukocyte Common Antigens - metabolism; Male; Metastases; Middle Aged; Multivariate analysis; Neoplasm Staging; Original Research; Patients; Prognosis; Stomach Neoplasms - metabolism; Stomach Neoplasms - pathology; Stomach Neoplasms - surgery; Surgery; Survival Analysis; Tissue Array Analysis; Treatment Outcome; tumor proportion
• ISSN: 2045-7634; 2045-7634
• DOI: 10.1002/cam4.1744

Background We hypothesized that the relative proportion of tumor (PoT) at the luminal surface can predict gastric cancer (GC) patient survival. Methods We measured the luminal PoT in resection specimens from 231 GC patients with stage II/III disease who had surgery at the Kanagawa Cancer Center, Yokohama, Japan. Tissue microarrays were used to assess the extent of immune cell infiltration by CD45 immunohistochemistry. Results were related to histopathological features and patient overall survival (OS). Results PoT was significantly lower in diffuse‐type (30%) compared to intestinal‐type GC (41%), P = 0.03. Patients with low PoT intestinal‐type GC survived significantly longer than patients with high PoT intestinal‐type GC (5 years OS: 78% vs 47%, P = 0.0112). Low PoT was an independent favorable prognostic factor in multivariate analysis in intestinal‐type GC. Low PoT was correlated with high content of CD45‐positive immune cells (P = 0.035). There was no relationship between PoT and survival in diffuse‐type GC. Conclusions This is the first study to identify a subgroup of patients with stage II/III intestinal‐type GC at high risk of recurrence by measuring PoT at the luminal surface. The relationship between PoT and immune cell content provides an initial insight into potential underlying biological mechanisms. We measured PoT at the luminal surface of the tumor as we wanted to evaluate whether PoT as a potential biomarker of high‐risk GC patients may be determined early on in patient management, for example, in diagnostic endoscopic biopsies.