414P - Clinical profile of gastrointestinal stromal tumour in Yangon General Hospital

Background

Gastrointestinal stromal tumours (GIST) are the most common mesenchymal tumours originating from the interstitial cells of Cajal and differentiates from other mesenchymal neoplasm by expression of CD117 oncogene. Most GISTs are found in the stomach followed by small bowels. Using NIH risk groups, the low risk GISTs were less frequent and the highest risk group was the commonest one. The main aim of this study was to evaluate demographic data , assess risk groups and study the clinical outcomes among GIST patients attending the Medical Oncology department , Yangon General hospital from 2015 to 2017.

Methods

Retrospective descriptive study.

Results

Among 73 patients, male: female is 2:1. The most common age group was 51-60 years. Regarding tumor site, small intestine was the most common site and the most patients were found to have tumor size between 11 to 20cm. According to TNM staging, 48% of patients were stage III. By using NIH risk stratification, it was found that 84% of patients were in high risk group. Tumour resection was performed in 77.8% and palliative resection was done in 22.2% of patients. CD117 immunostaining was performed in all 73 patients but CD117 expression was found in 69 patients. 4 patients were CD117 negative but CD34 positive. Therapy with imatinib (400–600mg) was given in 73 patients. Among them, 13 patients was occurred loss follow-up and could not assessed due to social and transportation difficulties. Three patients were expired due to disease progression. 57 patients were alive and taken imatinib up to 3 year. We initially assessed with USG and if there was suspected lesion in USG, we did further advanced imaging like CT. Among these patients who took imatinib up to 3 years, 5 patients was found to have recurrence and change to second line therapy. 52 out of 73 patients remained clinically stable and no recurrence up to 3 years. The most common side effect was generalized edema. The other side effects were whitening of skin and rash . 2 patients suffered dyspnea on exertion and assessed with echocardiogram showing reduced ejection fraction. Dose adjustment was done to these patients. 1 patient was found to have liver function derangement.Table:

414P

Conclusions

This study showed most patients presented with larger tumour sizes, high NIH risk and small intestine. Those who received imatinib up to 3 years had low rate of recurrence and well tolerated.

Clinical trial identification

Editorial acknowledgement

It would not have been possible without the guidance of our professors and co-authors who contributed their valuable expertise to the concepts displayed in this abstract.

Legal entity responsible for the study

Medical Oncology, Yangon General Hospital.

Funding

Has not received any funding.

Disclosure

All authors have declared no conflicts of interest.