Prevalence of Gastric Cancers among Patients Undergoing Upper Gastrointestinal Endoscopies in a Tertiary Care Hospital in Nepal: A Descriptive Cross-sectional Study

ABSTRACT Introduction: Gastric cancer is a common malignancy of the upper gastrointestinal (UGI) tract. Gastric cancer is a common cause of death worldwide. This research aimed to study the prevalence of gastric cancer among patients undergoing upper gastrointestinal endoscopies. Methods: A descriptive, cross-sectional study was conducted in the Department of Medicine at Manipal Teaching Hospital, Nepal, from January 2018 to June 2020. A total of 2640 subjects underwent upper gastrointestinal endoscopies over the study period. Ethical approval was taken from the institutional review committee of Manipal College of Medical Sciences (MEMG/ IRC/ 383/ GA). Data were analyzed by SPSS version 20. Results: The prevalence of gastric cancer among patients undergoing UGI endoscopies was 2.4%. The mean age of subjects was 58 ± 12.35 years (range of 31 to 96 years) with male predominance (M: F=1.9:1). Antrum was the most common site for gastric carcinoma. The most common morphology was ulcerative growth (46.9%). Adenocarcinoma (98.4%) was the most common histology, and the majority was of intestinal subtype (56.3%). Conclusions: Gastric cancer is not an uncommon finding in patients undergoing UGI endoscopies. Gastric cancers were commonly seen above 50 years of age and predominant in males. Patients with gastric carcinoma usually present late with advanced disease stages and unfavorable histopathology


INTRODUCTION
Cancer is one of the most dreaded non-communicable diseases that have become an important contributor to disease's global burden. 1 The gastrointestinal (GI) cancers are responsible for more cancers and more deaths from cancer than any other cancers. 2 Gastric cancers is the commonest upper gastrointestinal (UGI) malignancy and is the second most common cause of death worldwide. 3 A high incidence of gastric cancer has been reported from Southeast Asia attributed to the high consumption of preserved food containing carcinogenic nitrates. 4 Endoscopy followed by endoscopic biopsy is a very useful diagnostic tool for pathologies of the upper GI tract, including gastric cancers. 5 National data on the demographic profile of stomach cancers are scanty. This research is meant to study gastric cancer prevalence among patients undergoing UGI endoscopies attending medical gastroenterology clinic at a tertiary care Teaching Hospital in Gandaki province, Nepal. The calculated minimum sample size was 385.
Cases from January 2018 to June 2020 were studied from the records of the Endoscopy unit, departmental admission, and discharge summaries. All consecutive cases of 18 years and above who presented to the Medical Gastroenterology unit (under the department of medicine) either as outpatients or in patients who underwent upper GI endoscopy were enrolled for the study. Patients already diagnosed with gastric carcinoma or those with no histopathological confirmation or those with incomplete records, those with primary gastric lymphoma, gastrointestinal stromal tumor, and neuroendocrine tumor were excluded from the study. Studied variables include endoscopic findings, sites of lesions, and histopathological subtypes.
Contrast-Enhanced Computed Tomography ( PHILIPS Ingenuity 128 CT Scanner, NETHERLANDS Inc) scan of the abdomen and pelvis was done to complete the evaluation of upper GI tract and study of regional lymphadenopathies, ascites, and metastases. After hemodynamic stabilization, overnight fasting and premedications, and informed consent, an endoscopy (PENTAX EPK 700, PENTAX JAPAN Inc) was performed. Endoscopy findings were noted. At least 4 tissue biopsies were taken from the nonnecrotic gastric pathological site in 10% formalin and sent to the pathology department for histological assessment. The histologic tumor type of gastric cancer (GC) was classified according to the Lauren classification. (Intestinal, diffuse, and mixed type). The microscopes used were Carl Ziess Axiostar Plus and Olympus CX21. Endoscopy findings with biopsies from the suspected sites followed by histopathology were all helpful in the diagnosis of gastric cancer.
Data collected were collected in a preformed sheet. Data were entered in Microsoft Excel 2010 and analysis was done using SPSS version 20. All categorical data were expressed in percentage and absolute number. All continuous numerical data were expressed in mean ±SD. All tests were analyzed with a 95% confidence interval.

RESULTS
A total of 2640 subjects underwent upper GI endoscopies over the study period of 30 months. Sixty-four patients were detected with gastric cancer, demonstrating a prevalence of 2.4% among patients undergoing UGI endoscopies. The study group comprised of 42 (65.6%) males and 22 (34.4%) females (M: F=1.9:1). The mean age of subjects was 58±12.35 years with a range of 31 -96 years of age. Four (6.2%) patients were aged below 40 years of age. Patients were classified as per age group (Table 1). A majority (n=36; 56.25%) of cases were aged between 51 and 70.

DISCUSSION
In the current study, the prevalence of gastric cancer among patients undergoing UGI endoscopies was 2.4%. In a previous Nepalese study from this region in 2013 comprising of 2820 endoscopies by Shrestha et al. 6 , gastric carcinoma prevalence was reported to be 1.8%. The prevalence or detection of gastric cancer may be rising every year in this region.
The mean age of subjects was 58±12.35 years with male predominance (M: F=1.9:1). Majority (56.3%) of cases were aged between 51-70 years of age. In a previous Nepalese study by Ghosh et al. 7 , gastric tumors were seen even more (83%) in the same age group of 51-70. The mean ages were 57, 54, 54, and 51 years by Das et al. 8 , Cherian et al. 9 , Debbarma et al. 10 , and Kabir et al. 11 , respectively. These studies have mentioned that gastric carcinoma is commonly observed between 50 and 60 years of age with male predominance. In the current study, 6.2% of patients were aged below 40 years of age. In a study in Vietnam by Quach et al. 12 , gastric cancer incidence in young below 40 years of age was even higher (16.3%). So, this cancer is not only restricted to the elderly.
Antrum (48.4%) was the commonest site of gastric carcinoma, followed by carcinoma of the body in the current study. Antrum was similarly found to be the most common site of carcinoma according to Ghosh et al. 7  In the current study, gastric carcinoma was observed commonly with ulcerative lesions (46.9%), followed by ulceropoliferative (37.5%) and proliferative growth (15.6%). Saha et al. 15 had similar findings with ulcerative lesions most commonly (57.8%) followed by ulceroproliferative (24.9%) and polypoidal lesion (17.3%). In the study by Kabir et al. 11 , ulcerative (56%) was similarly the commonest growth followed by polypoidal (34%) and ulceroinfiltrative (10%) lesions.
Majority of these patients presented with Stage III carcinoma (46.8 %), followed by stage IV (25 %), stage II (18.8%), and Stage I (9.4%) in the present study. Most of the patients in the study by Barad et al. 14 in India also presented in stage III (62.7%). More than twothirds of the patients were diagnosed with advanced gastric cancer in a study in Iran. 16 Patients presented with advanced Stages III followed by stage IV even in the studies by Isobe et al. 17 in Japan and Park et al. 18 in South Korea. All these studies suggest that patients with gastric carcinomas usually present late and with advanced stages in Asian countries.
The most common histological morphology was intestinal adenocarcinoma (56.3%) in our study, consistent with other studies. 14,18,19 Intestinal type adenocarcinoma was similarly the commonest histology and was seen in 55.9% by Eskandar et al. 16  This study had its limitations. It was a retrospective study with no follow-ups. Clinical presentation, operability, and clinical outcomes of gastric cancers were not studied. The study reflects the findings of a specific geographical area.

CONCLUSIONS
Gastric cancers are not uncommon findings in patients undergoing UGI endoscopies. They were commonly observed in patients aged more than 50 years of age. Antrum was the most common site. The majority presented with ulcerative growth on endoscopy and advanced stages in CECT abdomen with unfavorable histopathology. Thus, it is recommended that when alarming features and chronic symptoms are present, a delay should not be made for evaluation with upper GI endoscopy. Biopsy of the pathological lesions followed by histopathological confirmation must be done to rule out UGI tract malignancies.