Management of gastrointestinal stromal tumors: Five years period, Tanta experience
Mohamed El-Shebiney1, Alaa Maria1 and Emad Sadaka1 and Ayman El-Namer2
1Clinical Oncology department, Faculty of Medicine, Tanta University, Egypt
2General Surgery department, Faculty of Medicine, Tanta University, Egypt
Abstract: Background: Gastrointestinal stromal tumors (GISTs) are the most common mesenchymal neoplasm of the gastrointestinal (GI) tract. Surgical resection has remained the mainstay of treatment of GISTs with a 5-year survival of 29–35%. Gastrointestinal stromal tumors have only been described based on their specific immunohistochemistry and the presence of particular KIT-related mutations which potentially make them targets for tyrosine kinase inhibition. We present our experience of managing GISTs, 5-years period. Methods:We reviewed clinical, pathological records and treatment outcome of 22 patients (14 men and 8 women) with GISTs treated at General Surgical and Clinical Oncology Departments, Tanta University Hospital during the period from Jan 2007 to Dec 2011. Results: The stomach was the most common site of origin (45.45%). The mean tumor diameter was 7±3.1 (range 4–18) cm. We detected advanced-stage tumors in 18.18% of patients. Complete resection was performed in 77.27% of patients. Mitotic count was greater than 5 high-power field (HPF) in 31.82 % patients. Immunohistochemical staining for CD117 was positive in 90.91% patients. The mean follow-up period was 26.7±15.1 (range 7–55) months. Distant metastases developed in 18.18% of all patients within an average of 14.5 (range 7–21) months. Local recurrence had occurred in 29.41% of patients who underwent complete surgical resection within an average of 11.4 (range 4–18) months. Imatinib mesylate therapy was administered for 11 patients (4 patients hade positive margins, 3 patients had locally recurrent disease and 4 patients had distant metastases) with a median survival of 21 (range 7-37) months. The median length of survival for all patients was 29 months and the 3-year overall survival (OS) and disease free survival (DFS) rates were 54.55% and 45.45% respectively. Three-year OS rates were 58.82 % versus 40% for patients who underwent complete surgical excision versus those who underwent incomplete surgical excision respectively (p=0.61). The 3-year OS rates were 76.92% versus 22.22% for low & intermediate versus high malignant risk patients respectively (p=0.008). Conclusion: Treatment of GISTs should be made on an individual basis. Surgical resection is considered the gold standard therapy for resectable GISTs and the completeness of the resection with negative margins is the main goal of surgery. Large multi-centers studies with large number of patients are needed for further insight into issues of tyrosine kinase inhibitors dosage, treatment duration and the selection, timing and monitoring of further therapeutic interventions.
[Mohamed El-Shebiney, Alaa Maria, Emad Sadaka and Ayman El-Namer. Management of gastrointestinal stromal tumors: Five years period, Tanta experience. Life Sci J 2013;10(1):1729-1735] (ISSN:1097-8135).http://www.lifesciencesite.com.
Key words: Gastrointestinal stromal tumors, c-KIT protein, Imatinib mesylate.