title: [Clinicopathological observation of gastric cancer with pathological complete response following neoadjuvant chemotherapy].
abstract: OBJECTIVE
  To observe the clinicopathological characteristics of gastric cancer with pathological complete response(pCR) following neoadjuvant chemotherapy.
  
  
  METHODS
  Data of gastric cancer patients who received neoadjuvant chemotherapy from 2002 to 2008 in the Beijing Cancer Hospital were reviewed. Five cases were found to have pCR. The slides were reviewed by two experienced pathologists independently. Histological structure, morphology of tumor cells, morphology and quantity of stromal cells were evaluated.
  
  
  RESULTS
  Structure of the gastric wall was distinguishable in all the 5 cases, while distortion and rupture of muscular layer were found in 2 cases. Exudative inflammatory reaction was present in the whole gastric wall including the serosa layer. Three patients had ulcerative lesions with epithelial layer shedding, and atypical hyperplasia was found around the border of the ulcer, and vascular endothelial cells were swollen. Residual distorted necrotic tumor cells resided in 1 case only and no residual tumor cells was present in the other 4 patients. Significant hyperplasia of fibroblasts was present in 4 cases, large amount of lymphocytes infiltration in 3 cases including concurrent plasma cell infiltration in 1 case, multinucleated giant cell reaction in the muscular layer of 1 case, and foam cells aggregation in 1 case with mucinous adenocarcinoma. In addition, there were 2 cases with pCR had lymph node metastasis.
  
  
  CONCLUSIONS
  For cases with pCR following neoadjuvant chemotherapy, heterogeneity of stromal cells reaction is found in previous tumor site. Furthermore, the response of primary tumor does not necessarily parallel to that of lymph nodes.
authors.affiliation: Department of Gastrointestinal Surgery, Peking University School of Oncology, Beijing Cancer Hospital and Institute, Beijing 100142, China.
authors.forename: Ai-wen
authors.initials: AW
authors.lastname: Wu
authors.forename: Fei
authors.initials: F
authors.lastname: Shan
authors.forename: Wei-cheng
authors.initials: WC
authors.lastname: Xue
authors.forename: Bin
authors.initials: B
authors.lastname: Dong
authors.forename: Lian-hai
authors.initials: LH
authors.lastname: Zhang
authors.forename: Zi-Yu
authors.initials: ZY
authors.lastname: Li
authors.forename: Zhao-de
authors.initials: ZD
authors.lastname: Bu
authors.forename: Xiao-jiang
authors.initials: XJ
authors.lastname: Wu
authors.forename: Xiang-long
authors.initials: XL
authors.lastname: Zong
authors.forename: Jia-fu
authors.initials: JF
authors.lastname: Ji
mesh_terms: D000328:Adult; D000971:Antineoplastic Combined Chemotherapy Protocols / Q000627:therapeutic use; D005260:Female; D006801:Humans; D008207:Lymphatic Metastasis; D008297:Male; D008875:Middle Aged; D020360:Neoadjuvant Therapy; D013274:Stomach Neoplasms / Q000188:drug therapy* / Q000473:pathology*