Gastric GIST with progressive mitotic index

Abstract

Gastrointestinal stromal tumors (GISTs) account for less than 1% of gastrointestinal tumors;they are the most common mesenchymal neoplasms of the gastrointestinal(GI) tract. GISTs are usually located in the stomach,but can occur anywhere along the gastrointestinal tract.GIST ranks third as histology after adenocarcinomas and lymphomas among the gastrointestinal tract.Case presentation.The patient, aged 58 years, is transferred from the Gastroenterology Clinic with symptoms of stenosis and hemorrhage from a endophytic submucosal tumor located on the posterior gastric wall, under the eso-gastric junction, objectified endoscopically and CT scan. Laparoscopic wedge resection was performed with three linear Endo-GIA staplers. The evolution was favorable. After 7 months (without chemotherapy because pTNM was T1NoMo), the patient is sent back by the gastroenterologist for „CT scan:perigastric lymphadenopathies”. The patient was operated laparoscopically converted.We found 10 tumors with typical malignant GISTs 3-10 cm diameter,on the peritoneal serosa:in the right subhepatic space, perigastric, left interhepato-phrenic, hepato-gastric;these were excised R0; with simple evolution. The immuno-histo-chemical examination specifies the diagnosis of GIST at the first and the second operation (DOG1,CD117,CD34-positively in tumor).Ki 67 was 15% in the tumor and the mitotic index <5/5 square mm at the moment of the first operation but in the metastatic tumor at the reintervention Ki 67 was 80% and mitotic index >5/5 square mm.Discutions.GIST tumours can be classified into low-risk and high-risk categories of recurrence depending on size, location, capsule rupture and mitotic activity. Disseminated metastases in the abdominal cavity are the most common clinical manifestations of malignancy. Complete surgical resection is recommended if bleeding or other symptoms are present. Tumour perforation, spontaneous or produced at the time of surgical resection, should be recorded because it has a high negative prognostic value due to peritoneal contamination. The average survival rate in localized disease is 5 years but in metastatic or recurrent disease is about 10-20 months. Conclusion. Complete excision of residual metastatic lesions has been shown to be associated with a favourable prognosis, provided that the patient responds to imatinib treatment; resection of tumour recurrence is accompanied by an average survival of 15 months. Gastric GIST recurrence risk depends of localisation, tumor size, mitotic index and capsular rupture.