A Review of Gastrointestinal Stromal Tumours- A Single Centre Experience

Abstract

Introduction: Gastrointestinal stromal tumour (GIST) is relatively rare. The clinical behaviour of GIST ranges from benign to frank sarcoma. The diagnosis is established through histopathological examination and immunohistochemistry profile. In Malaysia, the number of publications related to GIST is relatively rare. This study was therefore conducted to examine the demographic, histopathological and immunohistochemical features of GIST cases diagnosed in the Department of Pathology, Hospital Tengku Ampuan Afzan, Kuantan, Pahang from 2009 until 2014. Methods: Past histopathological records were reviewed. Demographic and histopathological and immunohistochemical data of patients diagnosed were collected. Results: There were 28 cases (14 males and 14 females) diagnosed as GIST. Mean age was 56.4 years, and the majority were above 40 years of age (85.7%). Stomach was the most common location (42.9%), followed by small intestine (28.6%). In 23 cases (82%), the tumours exhibited spindle cell morphology, while epithelioid cell and mixed cell types were seen in 3 cases (11%) and 2 cases (7%), respectively. Five cases were categorised as very low risk to low risk behaviour, while 18 cases were intermediate to high. None of the histological parameters analysed which include tumour morphology, necrosis, haemorrhage, nuclear atypia and mean number of mitoses showed significance difference between the different risk behaviour groups. Positivity with KIT (CD117), considered to be the defining immunohistochemistry feature, was negative in 2 cases. Conclusion: Although this study is a retrospective study, the findings contribute to the knowledge on GISTS in Malaysia. Future research related to GISTs in Malaysia should focus on molecular analyses for KIT and PDGFRA mutations for diagnostic confirmation especially in KIT-negative cases and also for the purpose of therapeutic response correlations.