Gastric cancer (GC) is the 5th most common cancer and the 3rd leading cause of cancer-related deaths worldwide. GC incidence and mortality rates vary widely across different geographical areas. In Italy, the province of Cremona is characterized by a high incidence, compared to the national one. For these reason a specialized population-based registry was set up.

The collection encompasses all GCs diagnosed in the province of Cremona since January the 1st, 2010. The main data sources were represented by the pathological records and patient clinical charts.

Up to November 2017, 1087 cases were collected. 876, those diagnosed until December 2015 to have a minimum of two years of follow-up, were analyzed. Male/female ratio was 1.4. The GLOBOCAN world age-standardized incidence rate (ASIR) per 100,000 was 20.8 for male and 12.7 for female, compared to the Italian average rates of 10.9 and 5.9, respectively. A decrease in incidence was register both in male (−1.92%) both in female (−3.21%). Overall differences between incidence across districts was noticed (P<0.001). Median age at diagnosis was lower for male than female (P<0.001). Helicobacter Pylori (HP) infection was present in less than 20% of evaluated cases, with differences across districts (P<0.001). The gene HER-2 resulted amplified in about 25% of cases. An association between sex of patient and site of insurgence of the tumour (P<0.001) was registered, as well as between sex and tumour istotype (P<0.05). More than half of cases was in advanced stage of disease at diagnosis and only about 40% underwent surgery. Median overall survival (OS) was 14.8 months for men and 18.5 for women. Age-standardized 5-years relative survival was 31.44% for men and 40.50% for female. Neoadjuvant treatment was performed in less than ten percent of pts who underwent surgery, and low was the rate of postoperative therapy adherence (about 40%). OS was strongly improved by adjuvant treatment (P<0.001) regardless the tumour istotype (HR=0.97, P=0.957). Overall, data available at diagnosis that impacted on survival, were: sex, age, tumour site and the grade of differentiation of cancer cells. Same analysis was made including also information available after diagnosis, resulting from a deeper tumour characterization and from the clinical pathway followed. In pts who did have surgery, parameters were: age at diagnosis (HR=1.086, P<0.001), the status of lymph nodes (HR=2.027, P<0.001), and furthermore both neoadjuvant (HR=3.186, P=0.003) both palliative (HR=2.293, P=0.013) therapies. In pts with advanced stage of disease at diagnosis, who did not have surgery, survival seemed to be impacted only by the grade of differentiation of malignant cells.

This study confirms the high GC incidence in the province of Cremona, with a geographical spread across districts. Moreover, was confirmed the high percentage of GCs detected in advanced stage of disease and the low rate of 5-year relative survival. Based on these findings, effective preventive interventional health strategies and screening procedures need to be implemented to reduce the impact of this pathology for this geographical area.