Evaluate the reliability of morphology standards for GIST pathologic type, staging and grading by retrospective analyzing clinical data; on this basis, establish a GIST standardized and individualized treatment mode to maximum benefit GIST patients, avoid under- and over-treatment.

1. Retrospective analysis of GIST cases in the recent five years: the GIST clinical data of Fudan University Zhongshan Hospital from 2007 January to 2012 December were collected. By reviewing the HE slides, GIST was evaluated by 12 indicators, NIH scheme and WHO standard. Accomplish the gene sequencing of KIT, PDGFRA, B-raf, and SDH. Follow up the patients about their treatment and prognosis. Analyze and compare the advantages and disadvantages of the histomorphology indicators, NIH scheme, and WHO standard.
2. Organize the first prospective cohort study of GIST individualized treatment based on the histomorphology. Obtain the evidence of histological assessment for GIST by following up patients for 3 years.
3. Establish an evaluation criteria based on the morphology of GIST. Make objective evaluations about GIST tumor size, tumor location and gene mutation status in the prognosis estimate. Make rules to effectively guide individualized treatment of GIST.

All patients pathologically diagnosed with GIST during the period from 2013 to 2015

patients diagnosed with GIST by pathology