Clinicopathological Characteristics and Prognosis of Mucinous Gastric Cancer.

BACKGROUND/AIM: Mucinous gastric carcinoma (MGC) has a poor prognosis. Due to the differences in clinicopathology factors between MGC and non-MGC (NMGC), it is difficult to compare them. In this study, we compared the clinicopathological characteristics and prognosis of MGC and NMGC patients.

PATIENTS AND METHODS: For gastric carcinoma (GC), 3,042 gastrectomy patients were included in the study and divided into the MGC (n=86) and NMGC (n=2,956) groups. The characteristics and prognoses of patients in both groups were compared before and after (both groups, n=86) propensity score matching.

RESULTS: Significant differences were observed in the tumor location (upper) (MGC group: 28.0% vs. NMGC group: 24.7%, p=0.003), tumor diameter (median) [65 mm (8-200 mm) vs. 40 mm (2-75 mm), p<0.001], lymph node metastasis (70.9% vs. 37.3%, p<0.001), venous invasion (57.0% vs. 40.4%, p<0.001), and lymphatic invasion (62.8% vs. 34.9%, p<0.001) before propensity score matching. The 5-year overall survival (OS) (70.9% vs. 76.2%, p=0.006) and cancer-specific survival (CSS) (75.5% vs. 82.4%, p=0.014) rates were significantly lower in the MGC group. After propensity score matching, there were no significant differences in either the 5-year OS (70.9% vs. 73.7%, p=0.230) or CSS (75.5% vs. 75.7%, p=0.587) rates. In addition, no substantial difference was observed in either of the recurrence forms.

CONCLUSION: MGC is rare and usually diagnosed at a more advanced stage. However, MGC and NMGC have similar prognoses.