Gastrointestinal stromal tumors (GIST): Contemporary insight of frequency, diagnosis, risk stratification and management

Gastrointestinal Stromal Tumors (GISTs) are rare, but life-threatening forms of cancer, which may arise anywhere in the gastrointestinal tract. The incidence rate and better understanding of GISTs have increased significantly with implementation of an appropriate up-to-date classification based on tyrosine-protein kinase (KIT) mutations and advancements in immunohistochemistry. Risk stratification is a crucial step in the management and prediction of the disease outcomes. Several factors such as primary site of occurrence, size of the tumor, mitotic activity, staining for proliferating cells and tumor necrosis predict the outcomes. Surgical resection remains as the gold standard in the treatment. Complete resection improves postoperative survival. Laparoscopic resection is associated with less intra-operative blood loss, early return of bowel function and oral feeding together with shorter length of hospital stay. However, laparoscopic resection is difficult to perform in large, unfavorably located GISTs and may result in disease progression, recurrence, and poor survival. Robot-assisted laparoscopic resection is being used to treat large and unfavorably located GISTs, especially placed at pylorus or cardia which is technically demanding operation. Imatinib-targeted therapy yields promising clinical responses and better survival in GIST patients. Large clinical trials are being conducted to establish the clinical implications of novel adjuvant and neo-adjuvant therapies for favorable outcomes in GISTs patients.