Research progress of relationship between peritoneal microenvironment and peritoneal metastasis of gastric cancer / 中华消化外科杂志

Peritoneal metastasis is one of the most frequent metastatic patterns of advanced gastric cancer, but the mechanism underlying remains unclear. The 'seed and soil’ theory is now well recognized for peritoneal metastasis of gastric cancer at present. The combination of various cells, extracellular matrix, and ascites components within the abdominal cavity provide a suitable microenvironment for the plantation, infiltra-tion, growth and metastasis of gastric cancer cells. Fully under-standing of peritoneal microenvironment will help to diagnose the peritoneal metastasis of gastric cancer and tumor recurrence, and provide theoretical basis for the development of drugs targeting peritoneal microenvironment. The authors review the main cell formation, ascites and immune microenvironment involved in the formation of the peritoneal microenvironment based on relevant literatures at home and abroad, and investigate the relationship between peritoneal microenvironment and peritoneal metastasis of gastric cancer.

Comparison of efficacy and safety of triple-drug treatment regimens for metastatic colorectal cancer / 中国肿瘤临床

Objective: To evaluate the preliminary efficacy and safety of the 5-fluorouracil/leucovorin, irinotecan, and oxaliplatin (FOLF-OXIRI) and capecitabine, irinotecan, and oxaliplatin (CAPIRINOX) regimens as first-line therapy for unresectable advanced colorectal cancer. Methods: Between January 2013 and November 2018, 73 patients with metastatic colorectal cancer (mCRC) were analyzed. All patients received first-line chemotherapy. Of them, 45 patients were administered FOLFOXIRI, and the remaining 28 patients were ad-ministered CAPIRINOX. The clinical outcomes and safety profiles were evaluated according to the objective response rate (ORR), con-version resection rate, and adverse effects. Results: The ORR, median progression-free survival (mPFS), and R0 resection rate in the FOLFOXIRI group were not statistically different from those in the CAPIRINOX group (60% vs. 57.1%, 7.7 months vs. 9.6 months, 24.4% vs . 17.9% , respectively; P>0.05). No treatment-related deaths occurred. The major adverse events were leukopenia, neutropenia, fa-tigue, nausea, vomiting, diarrhea, alopecia, aspartate aminotransferase/alanine aminotransferase elevation, and neurotoxicity. The to-tal rate of grade 3/4 adverse events in the FOLFOXIRI group was 33.3% (15/45), while the total rate of grade 3/4 adverse events in the CAPIRINOX group was 46.4% (13/28). Toxicities between the two groups were not statistically significant (P=0.263). Conclusions: Both the FOLFOXIRI and CAPIRINOX regimens are effective as first-line treatment for metastatic colorectal cancer. The triple-agent chemo-therapy was associated with good efficacy and tolerable toxicity.

Analysis of biological characteristics and prognosis on gastrointestinal stromal tumor with PDGFRA gene mutation / 中华胃肠外科杂志

OBJECTIVE@#To investigate the biological behavior characteristics of gastrointestinal stromal tumors (GIST) with PDGFRA mutation and the patients' survival, and elucidate the efficacy of imatinib therapy.@*METHODS@#Patients with PDGFRA D842V and non-D842V mutations were screened from a database of 1163 patients with GIST who were treated at Peking University Cancer Hospital from 2003 to 2018. Clinicopathological data of these patients were collected, including gender, age, tumor size, mitotic phase, primary position, metastatic site, and expressions of CD117, CD34, DOG-1. The association of gene mutations with biological behavior of GIST, prognosis of patients, and efficacy of imatinib therapy was examined. Fisher's exact test was used to compare the clinical characteristics of the two groups. Kaplan-Meier method was used to analyze overall survival and recurrence-free survival.@*RESULTS@#A total of 27 patients with PDGFRA mutations were screened, among whom the D842V mutation was 1.6%(19/1 163), and the rate of non-D842V mutation was 0.7%(8/1 163). There were 11 male patients and 8 female patients of D842V mutation with male to female ratio of 1.38:1 and median age of 56 (35-72) years. There were 4 male patients and 4 female patients of non-D842V mutations with male to female ratio of 1:1 and median age of 51.5 (34-82) years. The primary lesions of D824V mutation were located in stomach for 18 cases and in parenteral area for 1 case. The primary lesions of non-D842V mutation were located in stomach for 6 cases, in jejunoileum for 1 case and in colorectum for 1 case. The proportion of nuclear fission 10/50 HPF accounted for 3/19, and 5-10/50 HPF accounted for 5/19. Among non-D842V mutation patients, mitotic phase <5/50 HPF accounted for 6/8, 5-10/50 HPF accounted for 2/8. Of D842V mutation patients, positive CD117 was found in 15 cases(15/19); positive DOG-1 was found in 15 cases(15/19); positive CD34 was found in 16/17 cases. Among patients with non-D842V mutation, 7 patients were positive for CD117(7/8); only 5 patients were tested for CD34, and all 5 patients were positive(5/5); only 3 patients were tested for DOG-1, and all 3 cases were positive (3/3). The 3-year recurrence-free survival rate after radical resection in D842V mutation patients was 51.9%, and that in non-D842V mutation patients was 62.5% without significant difference(P=0.380). Recurrence-free rate did not decreased in patients with D842V mutation after adjuvant imatinib treatment and the benefit rate of first-line treatment with imatinib in patients with advanced disease was zero.@*CONCLUSIONS@#The PDGFRA gene mutation rate is low, mostly derived from gastric GIST. D842V and non-D842V mutations present inert biological behavior. D842V mutation GIST is resistant to imatinib, and non-D842V mutation GIST can obtain benefit from imatinib treatment.

Analysis of clinicopathological characteristics in 180 patients with wild type gastrointestinal stromal tumors / 中华胃肠外科杂志

<p><b>OBJECTIVE</b>To investigate the clinicopathological characteristics of 180 patients with wild type gastrointestinal stromal tumors(GIST).</p><p><b>METHODS</b>The clinicopathological data of 180 patients with wild type GIST treated in the Peking University Cancer Hospital between October 2001 and September 2013 were analyzed and compared to 513 mutant patients.</p><p><b>RESULTS</b>180 patients were included in this study, and the median age 52.5 years(16-78 years). The percentage of female was significantly higher than that of male among patients under the age of 40. Primary tumor sites mainly included stomach(45.6%) and small intestine(23.9%). The positive expression of CD117, DOG-1, and CD34 were 81.6%, 75.6%, and 74.7%, respectively, which were highest in stamach, secondly in small intestine. The percentage of tumor with length >5 cm was higher in patients under the age of 50 compared to patients more than 50 years, and a significant correlation was found between tumor size and mitosis. Compared to mutant patients, wild type patients had the following features: younger, primary tumor site of stomach, tumor length ≤ 2 cm, and the lower positive expression of CD117 and DOG-1.</p><p><b>CONCLUSIONS</b>The significant differences in primary tumor sites, tumor size, and the positive expression of CD117/DOG-1 were found between wild type GIST and mutant GIST, which suggested that wild type GIST might be an independent subgroup to be concerned in clinical practice.</p>