Clinical Analysis Of Multiple Primary Cancers With Gastric Cancer(GC-MPC) And Clinical Significance Of PD-L1 Expression

Part I Clinical analysis of 30 cases of multiple primary cancers with gastric cancer(GC-MPC) compared to 65 cases of gastric cancer Objective:To investigate the clinic pathological features, diagnosis and prognosis of multiple primary cancers with gastric cancer(GC-MPC). Method:To analysis retrospectively the patients' clinical data of 30 cases of multiple primary cancers with gastric cancer and 65 cases of gastric cancer between January 2008 and January 2014 in the first affiliated hospital of Nanchang university.. Results:1?The median age of 30 cases of GC-MPC was 54.7 years old when the patients was diagnosed. Male and female incidence ratio was 3.3:1, which was similar to 65 cases of gastric cancer. There were 8 cases of synchronous primary cancer and 22 cases of metachronous primary cancer. 16 patients were diagnosed with gastric cancer before the diagnose of another primary cancer(post-metachronous) and 6 patients were diagnosed with gastric cancer after another primary cancer(pre-metachronous).2?All patients had 30 malignancies of other organs. The most frequent type of other malignancy was colon cancer(30%),followed by rectum(26.67%)?lung(23.33%)?esophagus(6.67%)?nasopharyngeal(3.33%)?breast(3.33%)and pancreas malignancy(3.33%)3?The time interval between gastric cancer and other organ malignancy, the interval was 38.5 months, and 43.3% of other organ malignancies were diagnosed within 3 years before or after gastric cancer. The proportion of family history of cancer in GC-MPC(40%) was higher than that of GC(16.92%)(P<0.015)?4?The proportion of stage I and II in GC-MPC and GC was 63.3% and 20% respectively(P<0.05).5?All patients followed up to January 2016, the median survival time was 21 months in GC-MPC and 14 months in GC. The median survival time of pre-metachronous(62 months) was significantly better than post-metachronous(30 months) or synchronous cancer group(10 months)(P<0.0001). Conclusion:1?There was no significant difference in sex and in age of men and women GC-MPC usually occur in the elderly..2?The frequency of digestive system malignancy is significantly higher than other organ malignancy.3?The prognosis of metachronous GC-MPC was better than synchronous GC-MPC. Part II The expression and clinical significance of PD-L1 in multiple primary cancer with gastric cancer(GC-MPC) ObjectiveTo investigate the expression and clinical significance of PD-L1 in multiple primary cancer with gastric cancer(GC-MPC).To analyses the difference between multiple primary cancer with gastric cancer(GC-MPC) and gastric cancer alone(GC). MethodsThe expression of PD-L1 was detected by immunohistochemical(IHC) in 30 cases of GC-MPC and 65 cases of GC, respectively. Results1?In GC-MPC, 50% of gastric cancer tissues showed positive PD-L1 expression, The protein mainly located in cell membrane of gastric cancer cells. There was no difference between GC-MPC and GC(61.53%)(P=0. 29).2?There was no correlation between PD-L1 expression in the first primary cancer and the subsequent cancer(P>0.05).3?No relationship was observed between PD-L1 expression and the patients' clinicopathological characteristics in GC-MPC,such as sex(P=1)?age(P=0.705)?blood type(P=0.423)?tumor size(P=0.121)?T stage(P=0.256)?N stage(P=0.232)?TNM stage(P=0.464) ? vascular tumor thrombus(P=0.439) ? smoking history(P=0.256)?family history(P=0.136).4?Kaplan-Meier survival curve analysis showed the patients with positive PD-L1 expression(10 months) had shorter survival time than the pateints with negative PD-L1 expression(31 months)(P<0.05).The 3-years survival rate of PD-L1 positive group and PD-L1 negative group was 26.7% and 13.3%, respectively.5 ? Univariate COX regression analysis demonstrated PD-L1 over expression, later T staging, larger tumor size( > 5cm), and PD-L1 over expression of GC-MPC were poor prognostic factors. Moreover, multivariate COX regression analysis verified that high PD-L1 expression in GC cancer cells,T stage, tumor size, smoking history were independent prognostic factor of GC-MPC patients. Conclusion1?PD-L1 expression mainly located in the cell membrane of gastric cancer cells. There was no difference between GC-MPC and GC group.2 ? There was no correlation between PD-L1 expression and clinicopathological characteristics of GC-MPC patients.3?The expression of PD-L1 was negatively correlated with the survival time.PD-L1 positive expression in cancer cell was an independent prognostic factor.