104P - A multi-institutional epidemiological and oncological profile of gastrointestinal stromal tumors in the Lebanese population

Background

Gastrointestinal stromal tumor (GIST) is a rare type of soft tissue sarcoma that most commonly arises from gastric mesenchymal cells. This study represents the first-ever form of GIST registry or database in Lebanon. The aim of this study is to describe and compare the Lebanese cohort of GIST cases and their management to the findings of international reports and gold standards.

Methods

This is a retrospective medical chart review of GIST cases diagnosed at the American University of Beirut Medical Center and Hammoud Hospital University Medical Center between the years 1996 and 2017.

Results

The database includes 106 GIST cases with a median age of 63.5 years (24-90). The median tumor size is 6 cm (0.3-21) with the most common presenting symptoms being abdominal pain and anemia. Endoscopy is the most commonly utilized diagnostic modality (49%) with confirmatory biopsy done in 42% of the cases. The most common tumor location is gastric (56.7%) followed by the small intestine (32.7%) and colon (7.7%). Noteworthy, the most common tumor size in females is between 5-10cm while in males is between 2-5cm. The most common cell type identified is the spindle cell (65.7%). CD 117 and CD 34 are positive in 91% and 78% of the cases, respectively. Only 14.7% of the cases received neoadjuvant therapy in the form of chemo- or targeted therapy while 31% received adjuvant therapy in either form. For cases that received adjuvant imatinib or sunitinib, the median tumor size is 8.8cm (4-20cm). Most patients (91%) underwent surgery, either by laparotomy (66%) or laparoscopy (34%). Of those, 97.7% had negative surgical margins. Recurrence occurred in 18.7% of cases with regional and distant recurrence occurring equally (35%) versus local recurrence (30%). The 3- and 5-year disease-free survival is 80% and 76% respectively.

Conclusions

Findings from this collaborative study add to the international epidemiology of GIST. It also shows that GIST features, as well as medical and surgical practices in this Lebanese cohort, conform with those reported from other populations.

Clinical trial identification

Editorial acknowledgement

Legal entity responsible for the study

The authors.

Funding

Has not received any funding.

Disclosure

All authors have declared no conflicts of interest.