title: Comparison of five tumor regression grading systems for gastric adenocarcinoma after neoadjuvant chemotherapy: a retrospective study of 192 cases from National Cancer Center in China.
abstract: BACKGROUND
  Neoadjuvant chemotherapy has been increasingly practiced on gastric cancer (GC), and histological evaluation to predict outcome is urgent in clinical practice. There are five classic tumor regression grading (TRG) systems, including Mandard-TRG system, the Japanese Gastric Cancer Association (JGCA)-TRG system, College of American Pathologists (CAP)-TRG system, China-TRG system and Becker-TRG system.
  
  
  METHODS
  Totally, 192 patients of gastric adenocarcinoma (including adenocarcinoma of the esophagogastric junction) treated by neoadjuvant chemotherapy and surgery were evaluated using the above five TRG systems. The clinicopathological characteristics were also assessed. The correlation among TRG systems, clinicopathological characteristics and prognosis were analyzed.
  
  
  RESULTS
  All the five TRG systems were significantly correlated with differentiation, postsurgical T category, postsurgical N category, American Joint Committee on Cancer (AJCC) stage, lymph-vascular invasion, perineural invasion, as well as tumor size. All the five TRG systems were statistically significant in univariate Cox survival analysis. However, only postsurgical T category, postsurgical N category and R0 resection were independent in multivariate Cox survival analysis. The tight correlation between the TRG systems and other characteristics such as postsurgical stage might affect the independent prognostic role of the TRG systems. As compared with other TRG systems, the hazard ratio of no/slightly response in both Mandard TRG system and JGCA TRG system revealed higher hazard of death and disease progression than that of severe response when using univariate Cox survival analysis. The median survival time of complete response and nearly complete response were much longer than that of partial response, all classified by Mandard-TRG system. This could help clinicians predict prognosis more reasonably than JGCA-TRG which does not have the category of nearly complete response.
  
  
  CONCLUSIONS
  We recommend Mandard-TRG system for GC after neoadjuvant chemotherapy due to its better prediction of prognosis.
authors.affiliation: Department of Pathology and Resident Training Base, National Cancer Center/Cancer Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China.
authors.forename: Yuelu
authors.initials: Y
authors.lastname: Zhu
authors.affiliation: Department of Medical Oncology, National Cancer Center/Cancer Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China.
authors.forename: Yongkun
authors.initials: Y
authors.lastname: Sun
authors.affiliation: Department of Cancer Epidemiology, National Cancer Center/Cancer Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China.
authors.forename: Shangying
authors.initials: S
authors.lastname: Hu
authors.affiliation: Department of Cancer Epidemiology, National Cancer Center/Cancer Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China.
authors.forename: Yong
authors.initials: Y
authors.lastname: Jiang
authors.affiliation: Department of Pathology and Resident Training Base, National Cancer Center/Cancer Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China.|Department of Pathology, Esophageal Carcinoma Hospital of Linzhou, Linzhou, Henan, China.
authors.forename: Jiangying
authors.initials: J
authors.lastname: Yue
authors.affiliation: Department of Pathology and Resident Training Base, National Cancer Center/Cancer Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China.
authors.forename: Xuemin
authors.initials: X
authors.lastname: Xue
authors.affiliation: Department of Medical Oncology, National Cancer Center/Cancer Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China.
authors.forename: Lin
authors.initials: L
authors.lastname: Yang
authors.affiliation: Department of Pathology and Resident Training Base, National Cancer Center/Cancer Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China. xuely@cicams.ac.cn.
authors.forename: Liyan
authors.initials: L
authors.lastname: Xue
mesh_terms: D000230:Adenocarcinoma / Q000188:drug therapy* / Q000401:mortality / Q000473:pathology; D000328:Adult; D000368:Aged; D000971:Antineoplastic Combined Chemotherapy Protocols / Q000627:therapeutic use*; D017024:Chemotherapy, Adjuvant; D002681:China; D002945:Cisplatin / Q000008:administration & dosage; D018572:Disease-Free Survival; D000077143:Docetaxel; D004338:Drug Combinations; D004943:Esophagogastric Junction; D005260:Female; D005472:Fluorouracil / Q000008:administration & dosage; D005743:Gastrectomy; D006801:Humans; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D020360:Neoadjuvant Therapy; D009361:Neoplasm Invasiveness; D009367:Neoplasm Staging; D009944:Organoplatinum Compounds / Q000008:administration & dosage; D000077150:Oxaliplatin; D010094:Oxonic Acid / Q000627:therapeutic use; D011379:Prognosis; D016016:Proportional Hazards Models; D011725:Pyridines / Q000627:therapeutic use; D012074:Remission Induction; D012189:Retrospective Studies; D013274:Stomach Neoplasms / Q000188:drug therapy* / Q000401:mortality / Q000473:pathology; D016019:Survival Analysis; D043823:Taxoids / Q000008:administration & dosage; D005641:Tegafur / Q000627:therapeutic use; D016896:Treatment Outcome; D047368:Tumor Burden
chemical_list: D004338:Drug Combinations; D009944:Organoplatinum Compounds; D011725:Pyridines; D043823:Taxoids; C586502:tegafur-gimeracil-oteracil; D000077150:Oxaliplatin; D005641:Tegafur; D000077143:Docetaxel; D010094:Oxonic Acid; D002945:Cisplatin; D005472:Fluorouracil
keywords: Gastric cancer; Neoadjuvant chemotherapy; Tumor regression grading