Abstract:
Background: Gastric cancer is associated with high morbidity and mortality due to the late onset of symptoms. It is the third leading cause of mortality around the world. The aim of this study was to determine molecular profiles of Rwandan samples for mutations that could potentially identify new targets for treatment
Methods: From 12th August 2015 to 30th November 2016, we conducted an analytical cross-sectional study by enrolling 76 patients. The participants were patients coming for EGD endoscopy visualized endoscopically to have gastric tumor lesions. 76 pair biopsies were sent for pathological evaluation at CHUK then 97 specimens sent to Dartmouth Hitchcock Medical Center for genetic analysis where DNA was extracted from fixed tissues using the QIAamp DNA FFPE Tissue Kit and then processed.
Results: Among 76 patients with gastric tumor lesions, males were 55.3% and females were 44.7%. There was a preponderance increase of males. 46% of our participants were from Eastern Province; roughly 15% were coming from North, South and Kigali City respectively. 76.3% were from rural area. 85.5 % of patients had low level of education. 46% (35/74) have smoked. 78.9% histopathology concordance: gastric malignancy vs benign. Malignancy 89.5%: Intestinal adenocarcinoma 47%, Diffuse adenocarcinoma 21%, Mixed 10.5%, Lymphoma 10.5%. There was a significant association between types of gastric cancer and age. P<0.038. Relatively, there was an increase in diffuse type cancer in younger age and Intestinal type in old age. Higher total LCN2 expression in samples + gastric cancer, H pylori + compared to H pylori neg, Not statistically significant P<0.744, probably due to small sample size (n=19). Twelve mutations in 9 biopsies 41% (9/22) were identified among the sequenced specimens. TP53 was the most common mutation 50%. The only targetable mutation was PTEN 25%.
Conclusion: This study is a very big achievement in terms of gastric cancer exploration in Rwanda, a short overview from the demographic distribution pattern, risk factors, clinical presentation and histopathology types to the genetic profile level of gastric cancer. This study showed the feasibility of Next Generation Sequencing on gastric specimen and a paucity of mutations in gastric cancer. PTEN mutation was a potential for targeted therapy.
