1.Assessment result of maintain a proper hand hygiene conditions in healthcare facilities of Mongolia
Bolor B ; Batdulam D ; Nasantogtokh S ; Myagmardorj Ch ; Myagmarjargal M ; Unurzaya E ; Oyun-Erdene O ; Enkhjargal A ; Tsegmed S
Mongolian Medical Sciences 2025;211(1):28-35
Introduction:
Safe and accessible WASH services in healthcare facilities are crucial for maintaining high
quality care, especially for maternal and newborn health. The WHO-UNICEF JMP on Water
Supply, Sanitation, and Hygiene provides reports on progress in water supply, sanitation,
and hygiene services at global, regional, and national levels, covering populations, schools,
and healthcare facilities. This assessment was conducted to address the insufficient data on
the level of hand hygiene services in healthcare facilities, following the methodology of the
JMP.
Materials and Methods:
A cross-sectional study was conducted in 319 healthcare facilities. Availability of hand hygiene
services in the study healthcare facilities was assessed using questionnaire of methodology
of the JMP. Data were analyzed using SPSS 25.0 software. Relevant parametric and non
parametric statistical analysis were conducted.
Results:
Overall, 72% and 28% of healthcare facilities had basic and limited hand hygiene service
respectively. About 18% of private healthcare facilities had limited hand hygiene service
compared to 34% of state healthcare facilities. While 20% of urban healthcare facilities had
limited hand hygiene service, 56% of rural healthcare facilities do. When examining the
level of hand hygiene services by type of medical care, specialty hospitals have 100% basic
services. Among primary care facilities, 83% of family health centers provide basic services,
while 41% of soum and village health centers meet these standards.
Conclusion
The basic hand hygiene services in urban healthcare facilities and specialty hospitals were
generally sufficient. There need to enhance basic hand hygiene service at the soum and village level. Among the assessed facilities, 81.0% met four out of the five key hand hygiene
requirements outlined in the national standard. However, additional budget allocation for
maintenance and operational costs for keeping soap and sustaining water running remains
crucial to ensure sustained compliance and quality.
2.Study of human echinococcosis
Rolomjav L ; Bayar Ts ; Enkhjargal A ; Suvd B ; Burmaajav B
Mongolian Medical Sciences 2025;212(2):52-61
Human echinococcosis is a zoonotic disease (a disease that is transmitted to humans from
animals) that is caused by parasites, namely tapeworms of the genus Echinococcus. A
number of herbivorous and omnivorous animals act as intermediate hosts of Echinococcus.
They become infected by ingesting the parasite eggs in contaminated food and water, and
the parasite then develops into larval stages in the viscera. Alveolar echinococcosis usually
occurs in a wildlife cycle between foxes or other carnivores with small mammals (mostly
rodents) acting as intermediate hosts. Domesticated dogs and cats can also act as definitive
hosts. Human infection with E. granulosus leads to the development of one or more hydatid
cysts located most often in the liver and lungs, and less frequently in the bones, kidneys,
spleen, muscles and central nervous system. In endemic regions, human incidence rates for
cystic echinococcosis can reach more than 50 per 100 000 person-years, and prevalence
levels as high as 5%–10% may occur in parts of Argentina, Peru, East Africa, Central Asia
and China. In livestock, the prevalence of cystic echinococcosis found in slaughterhouses in
hyperendemic areas of South America varies from 20%–95% of slaughtered animals. The
highest prevalence is found in rural areas where older animals are slaughtered. Depending on
the infected species involved, livestock production losses attributable to cystic echinococcosis
result from liver condemnation and may also involve reduction in carcass weight, decrease in
hide value, decrease of milk production, and reduced fertility. Ultrasonography imaging is the
technique of choice for the diagnosis of both cystic echinococcosis and alveolar echinococcosis
in humans. This technique is usually complemented or validated by computed tomography
(CT) and/or magnetic resonance imaging (MRI) scans. The choice must primarily be based
on the ultrasound images of the cyst, following a stage-specific approach, and also on the
medical infrastructure and human resources available. Worldwide, there may be in excess
of 1 million people living with these diseases at any one time. Many of these people will be
experiencing severe clinical syndromes which are life-threatening if left untreated. Even with
treatment, people often face reduced quality of life. For cystic echinococcosis, there is an
average of 2.2% post-operative death rate for surgical patients and about 6.5% of cases
relapse after an intervention, thereby requiring prolonged recovery time.
3.Comparative analysis of household indoor PM2.5 concentrations and prevalence of hypertension between cities
Anujin M ; Myagmarchuluun S ; Erkebulan M ; Ser-Od Kh ; Shatar Sh ; Gantuyаa D ; Enkhjargal G ; Munkh-Erdene L ; Gregory C. Gray ; Jungfeng Zhang ; Damdindorj B ; Ulziimaa D ; Davaalkham D
Mongolian Journal of Health Sciences 2025;89(5):5-10
Background:
According to the World Health Organization (WHO), 6.7 million people die annually due to air pollution
caused by solid fuel use, with the majority of deaths resulting from respiratory diseases and cardiovascular conditions. In
Mongolia, air pollution ranks as the fourth leading risk factor contributing to mortality, following hypertension, diabetes,
and other major health risks. Although there have been numerous studies on outdoor air pollution in Mongolia, research
linking indoor air pollution at the household level with the health status of residents remains limited.
Aim:
To compare indoor PM2.5 concentrations in households of Ulaanbaatar and Darkhan and examine their association
with hypertension during the winter season.
Materials and Methods:
The study was conducted during November and December 2023, and January 2024, involving
240 households in Ulaanbaatar and Darkhan. Indoor PM2.5 concentrations were measured using Purple Air real-time
sensors continuously for 24 hours over approximately one month. After measuring indoor air pollution, individuals aged
18–60 years living in the selected households were recruited based on specific inclusion criteria. Blood pressure was
measured three times and the average value was recorded. Information on respiratory illnesses was collected through
structured questionnaires. Statistical analysis was performed using STATA version 19.0.
Results:
A total of 241 households participated in the study, with 116 from Ulaanbaatar and 125 from Darkhan. Of the
participants, 46.5% were male and 53.5% were female. In terms of housing type, 96 households (39.8%) lived in gers,
97 (40.2%) lived in stove-heated houses, and 48 (19.9%) lived in apartments. Among all participants, 66.0% (n=159) had
hypertension and 34.0% (n=79) had normal blood pressure. Among participants aged over 40, 69.9–88.5% had hypertension, which is statistically significantly higher compared to younger individuals (p=0.0001). By body mass index, 75.3%
(n=72) of overweight individuals and 78.4% (n=58) of obese participants had hypertension, showing a statistically significant difference compared to participants with normal weight (p=0.0001). The 24-hour average concentration of indoor
PM2.5 was measured using the Purple Air device, and the levels in gers and stove-heated houses exceeded the limit set
by the MNS 4585:2025 standard (37.5 µg/m³)
Conclusion
This study identified a relationship between environmental factors, such as air pollution and housing type,
and the prevalence of hypertension. The indoor PM2.5 concentration in gers and stove-heated houses was above the standard limit, indicating a negative impact on the health of those residents. Furthermore, the high prevalence of hypertension
among participants over the age of 40 and those who are overweight suggests a possible link to lifestyle and environmental conditions.
4.Study of the stomatal cell in certain saponin containing medicinal plants in mongolia
Nurdana B ; Khulangoо B ; Densmaa L ; Norovnyam R ; Enkhtuul B ; Khuvtavilan B ; Munkhzul B ; Buyanjargal E ; Daariimaa Kh ; Enkhjargal D ; Turtushikh D ; Amarjargal T
Mongolian Journal of Health Sciences 2025;89(5):33-38
Background:
Saponins are secondary metabolites in plants that play an important role in defense mechanisms and
physiological processes. Since stomatal cells are crucial for gas exchange and water balance in plant tissues, studying the
anatomical and biochemical features of stomatal cells in saponin-rich plant species provides insight into the interactions
between these compounds and cellular mechanisms. This serves as the basis of our study.
Aim:
To determine the structure, types, and functions of stomatal cells in saponin-containing medicinal plants
Materials and Methods:
During June–September 2024, nine species of saponin-containing medicinal plants were
collected from Bulgan, Tuv provinces, and “Gorkhi-Terelj National Park” in Mongolia. Prepared microscopic specimens
were examined using macroscopic and microscopic techniques to study the structure, position, number, and epidermal
features of stomatal cells.
Results:
The study revealed that Anemone crinita Juz. exhibited the highest stomatal density (107 stomata/mm²) and
epidermal cell density (229 cells/mm²), indicating strong adaptation and protective capacity in arid conditions. Vicia
baicalensis (Turcz.) B. Fedtsch. showed the highest stomatal index (39.6), highlighting its significant role in regulating
transpiration. Stomatal types varied among species:
• Anomocytic stomata were observed in Potentilla multifida and Vicia baicalensis.
• Anisocytic stomata were found in Delphinium grandiflorum and Ranunculus borealis.
• Paracytic stomata were present in Gentiana algida, Adenophora remotiflora, Helianthemum nummularium,
Anemone crinita, and Ranunculus acris.
Conclution
In the study of the structure, form, and number of stomatal cells in saponin-containing plants growing in
Mongolia, Anemone crinita Juz. was found to have the highest number of stomatal and epidermal cells, indicating its high
efficiency in gas exchange, water regulation, and protection against external stress. Furthermore, Vicia baicalensis (Turcz.)
B.Fedtsch. showed the highest stomatal index, confirming its strong capacity for active regulation of gas exchange.
The variation in stomatal cell types among plant species was identified as playing an important role in ecological and
biological adaptation as well as protective mechanisms.
5.Results of a comparative study between monitoring stations and real-time low-cost sensor measurements (PurpleAir) for PM2.5
Buyantushig B ; Enkhjargal G ; Jargalsaikhan G ; Ulziikhutag B ; Ulziimaa D ; Damdindorj B ; Davaalkham D
Mongolian Journal of Health Sciences 2025;89(5):176-179
Background:
Particulate matter in ambient air is an important risk factor for cardiovascular and respiratory diseases.
Accurate and appropriate air quality monitoring is therefore critical for public health. In this context, it is necessary to
investigate the feasibility of using low-cost direct monitoring devices (such as PurpleAir) in outdoor environments during
the winter season, particularly in urban areas where fixed monitoring stations are not available.
Aim:
To assess and compare the outdoor PM2.5 concentrations in Ulaanbaatar and Darkhan during the winter season.
Materials and Methods:
The study was conducted in the capital city of Mongolia. The data collected for 45 days during
the winter season, from December 9, 2024 to February 14, 2025. Continuous low-cost sensor was collected using a light
scattering device (PurpleAir Classic) at a total of 25 locations and for 24 hours. Of these, 1 location was located next to
a fixed measurement point and 3 locations (Zuun 4 zam, Yarmag, Selbe) were located within 200m of the study area, and
the measurement results were compared using PM2.5. We used R software for statistical analysis.
Results:
The average PM2.5 concentration measured at the 13 fixed monitoring sites during the study period was 65 μg/
m³, while the average from the 25 PurpleAir sensors was 88 μg/m³. Parallel measurements conducted with the PurpleAir
sensors and the UB4 fixed monitoring station showed a moderate correlation (r=0.44, R²=0.22, p<0.05). The measurement results at the Zuun 4 zam, Yarmag, and Selbe locations have a moderate correlation (r=0.38, r=0.61, r=0.25).
Conclusion
In situations where it is not possible to measure PM2.5 particulate matter in outdoor air automatically or by
conventional methods, it is possible to monitor air quality by measured by low-cost sensors.
6.Comparative Analysis of Outdoor Particulate Matter Concentrations in Ulaanbaatar Using Direct Measurements and Fixed Monitoring Station Data
Ulziikhutag B ; Enkhjargal G ; Buyantushig B ; Nyamsuren B ; Shatar Sh ; Gantuya D ; Myagmarchuluun S ; Gregory Gray ; Junfeng Zhang ; Ulziimaa D ; Damdindorj B ; Davaalkham D
Mongolian Journal of Health Sciences 2025;89(5):112-117
Backgroun:
Air pollution is a major global public health concern that poses serious risks to human health regardless of
a country’s level of economic or technological development. According to the World Health Organization (WHO, 2021),
nine out of ten people worldwide breathe polluted air, and air pollution is responsible for the deaths of approximately
800 people every hour and 13 people every minute. Prolonged exposure to polluted air has been linked to a wide range
of chronic illnesses, including chronic obstructive pulmonary disease (COPD), lung and bronchial cancers, asthma, and
stroke. In Mongolia, air pollution reaches its highest levels during the winter months, particularly in Ulaanbaatar, where
the majority of the country’s population resides. A study conducted by Enkhjargal G. (2012) reported that the concentrations
of PM10 and PM2.5 in Ulaanbaatar were 7–8 times higher than the WHO recommended guidelines. In response
to such challenges, many countries have increasingly adopted low-cost, direct measurement devices such as PurpleAir
to monitor air quality. These devices are valued for their accessibility, network connectivity, and potential role in smart
city pollution management systems. Despite their global application, there remains a lack of research in Mongolia on the
use of PurpleAir sensors to measure PM2.5 concentrations and compare the results with official monitoring station data.
Addressing this gap is essential for improving local air quality monitoring capacity and informing effective public health
and environmental policies.
Aim:
Determination of PM2.5 particulate matter pollution in the outdoor environment of Ulaanbaatar city using a direct
measurement device (Purple Air).
Materials and Methods:
A cross-sectional study design was employed. Direct measurement devices (Purple Air) were
installed in selected districts of central Ulaanbaatar between December 2024 and February 2025, measuring PM2.5 concentrations
at two-minute intervals over 24-hour periods. All data were statistically processed and analyzed using the
SPSS-26 software package.
Results:
The average concentration of PM2.5 particles in the air of Ulaanbaatar city in winter is 66.68 μg/m3. Compared
to the districts, the highest concentration was determined in SKHD (118.58±90.22 μg/m3), while the lowest concentration
was determined in KHUD (42.37±43.51 μg/m3). Compared to the days of the week, the highest concentrations were measured
on Monday (76.68±71.98 μg/m³), Saturday (77.50±71.63 μg/m³), and Sunday (80.34±74.45 μg/m³). The highest
concentration of PM2.5 particles occurred from 6 pm to 1 am, and the lowest concentration was measured during the day
(between 2 pm and 4 pm). The highest concentration of PM2.5 was measured in December (74.22±73.45 μg/m3), while
the lowest concentration was measured in February (50.25±57.44 μg/m3).
Conclusion
The concentration of PM2.5 in the air of Ulaanbaatar city is 1.7 times higher than the general standard and
technical requirements of Mongolia in winter, and the highest concentration is in the SKHD. The highest concentration of
PM2.5 occurs more often in December and at night than in the winter months.
7.Comparative Analysis of Outdoor Particulate Matter Concentrations in Ulaanbaatar Using Direct Measurements and Fixed Monitoring Station Data
Maralmaa E ; ; Yerkyebulan M ; Ser-Od Kh ; Shatar Sh ; Gantuya D ; Munkh-Erdene L ; Enkhjargal G ; Myagmarchuluun S ; Gregory Gray ; Junfeng Zhang ; Ulziimaa D ; Damdindorj B ; Davaalkham D ; ; Darambazar G
Mongolian Journal of Health Sciences 2025;89(5):105-111
Background:
Particulate matter with an aerodynamic diameter of 2.5 micrometers or smaller (PM2.5) penetrates
deep into the alveoli through the respiratory tract and is characterized by its ability to induce oxidative stress, systemic
inflammation, and vascular inflammation. Mongolia ranks among the countries with the highest levels of air pollution. In
Ulaanbaatar, where more than half of the country’s population resides, wintertime PM2.5 concentrations often exceed 200
μg/m³, which is about eight times higher than the World Health Organization (WHO) guideline value. A study involving
1,200 adults in Ulaanbaatar showed that quality of life deteriorated sharply during periods of high air pollution, with
effects more pronounced among individuals who already had impaired respiratory function.
Aim:
To examine the relationship between indoor household PM2.5 concentrations and lung function indicators among
adults in Ulaanbaatar and Darkhan.
Materials and Methods:
This analytical cross-sectional study recruited adult participants from Ulaanbaatar and Darkhan
through targeted sampling. Household air quality was measured using PurpleAir sensors, which were installed in
participants’ homes for one month. After exposure measurement, lung function was assessed via spirometry. Statistical
analyses were conducted using SPSS version 25.0.
Results:
A total of 236 participants were included: 114 (48.3%) from Ulaanbaatar and 122 (51.7%) from Darkhan. The
sample consisted of 111 men (47.0%) and 125 women (53.0%). The mean indoor PM2.5 concentration was 66.24 μg/m³
(SD 44.87 μg/m³), ranging from a minimum of 7.79 μg/m³ to a maximum of 264.55 μg/m³. Stratification by housing type
showed the highest PM2.5 levels in gers (82.34 μg/m³), followed by detached houses (67.34 μg/m³), while apartments
had the lowest concentrations (32.24 μg/m³). Correlation analysis revealed statistically significant negative associations
between PM2.5 levels and measures of expiratory function, including the FEV1/FVC ratio, peak expiratory flow (PEF),
and mid-expiratory flow (FEF25–75). Reduced forced vital capacity (FVC) was observed in 9.4% of participants, reduced
forced expiratory volume in one second (FEV1) in 15.3%, and a decreased FEV1/FVC ratio in 3.8%.
Conclusion
Indoor household PM2.5 concentrations were highest in gers, and expiratory flow-related lung function
parameters showed significant negative associations with particulate exposure. This suggests that indoor PM2.5 primarily
affects airflow limitation rather than overall lung volumes in this population.
8.Reliability Assessment of the Mongolian Translation of a Questionnaire for Evaluating Children’s Health Literacy Concepts
Munkhjargal B ; Basbish Ts ; Tuyaa S ; Enkhjargal Ya
Mongolian Journal of Health Sciences 2025;89(5):142-145
Background:
Although early attention to children’s and adolescents’ health education is important, research assessing the
health knowledge of children under 13 is limited, and a validated assessment tool has not yet been developed; this forms
the rationale for the present study.
Aim:
Assessing the Reliability of the Mongolian Translation of a Questionnaire for Evaluating Children’s Fundamental
Health Concepts.
Materials and Methods:
This cross-sectional study was conducted in May–June 2025 among children aged 8–11 years
attending public general education schools in the Khan-Uul, Bayanzurkh, and Sukhbaatar districts of Ulaanbaatar. Of a total
population of 459 eligible students, 352 participated in the study. Data were collected using a structured questionnaire
consisting of 12 sociodemographic items and 15 items from the Health Literacy Assessment Tool for Children (HLSChild-
Q15), resulting in a total of 27 items. Statistical analyses were performed using SPSS version 21.0, with p-values
less than 0.05 considered statistically significant.
Results:
A total of 352 students participated in the study. By gender, the majority were girls, accounting for 57.1%
(n=201), while boys comprised 42.3% (n=149). Regarding grade level, 24.7% (n=87) were in third grade, 60.5% (n=213)
in fourth grade, 11.4% (n=40) in fifth grade, and 3.1% (n=11) in sixth grade. By age, 9.1% (n=32) were 8 years old, 36.4%
(n=128) were 9 years old, 43.2% (n=152) were 10 years old, and 11.4% (n=40) were 11 years old. Internal consistency
was acceptable, with Cronbach’s α=0.82. Exploratory factor analysis revealed three factors, explaining 56.3% of the
total variance. The sampling adequacy was acceptable (KMO=0.596), and Bartlett’s test of sphericity was significant,
χ²(105)=2615.78, p<0.001, indicating suitability for factor analysis.
Conclusion
This study demonstrated that the Mongolian version of the HLS-Child-Q15 questionnaire meets the requirements
of reliability and construct validity, indicating that it is an appropriate instrument for assessing the foundational
concept of health literacy among children in Mongolia.
9.Study of EGFR Gene Mutation Detection in Non-Small Cell Lung Cancer
Mergen D ; ; Tamir B ; Dolgorsuren P ; Ganzorig B ; Undarmaa T ; Enkhjargal B ; Adilsaikhan M
Mongolian Journal of Health Sciences 2025;90(6):105-111
Background:
Lung cancer remains the leading cause of cancer-related mortality worldwide, accounting for approximately
1.8 million deaths annually and representing 18% of all cancer deaths¹. According to the GLOBOCAN 2024 report, 2.4
million new cases were registered globally, ranking second after breast cancer². Non-small cell lung cancer (NSCLC) constitutes
85% of lung cancer cases, with adenocarcinoma being the most common subtype³. The objective of this study is
to map the prevalence of HER2 activation and mutations in EGFR, EML4-ALK, ROS1, BRAF, and KRAS genes among
lung cancer patients in Mongolia, and to evaluate their correlations with clinical and morphological parameters (age, sex,
smoking status, stage, and morphology).
Aim:
To determine the distribution pattern of HER2 activation and EGFR, EML-ALK, ROS1, BRAF, KRAS gene mutations
among patients with lung cancer in Mongolia, and to evaluate their associations with clinical and morphological
characteristics.
Materials and Methods:
A retrospective study was conducted using archived materials from lung cancer patients at the
Clinical Pathology, Molecular Genetics, and Pathology Laboratories of the National Cancer Center of Mongolia, covering
the period from 2019 to June 2025.
DNA Extraction from Tumor Tissue: Formalin-fixed paraffin-embedded (FFPE) tissue blocks from patients diagnosed
with lung cancer, stored in the pathology department archives, were selected for the study. Sections of 5–10 μm thickness
were cut, mounted on glass slides, stained with hematoxylin and eosin (H&E), and reviewed by a pathologist. Areas containing
≥20–30% tumor cells were identified and macro-dissected for analysis.
Real-Time PCR Assay for Detection of EGFR/BRAF/KRAS/EML4-ALK/ROS1 Mutations: EGFR mutation detection
was performed using the PANAMutyper™ EGFR Mutation Detection Kit (Panagene, Daejeon, South Korea) according
to the manufacturer’s instructions. PCR reactions were carried out on a compatible instrument (Roche LightCycler 480,
Germany) as recommended by the manufacturer. Statistical analysis was performed using Prisma-10 software.
Results:
A total of 282 lung cancer cases were included in the study. EGFR mutations were detected in 44% of cases and
were absent in 56%. No significant age-related differences were observed (p=0.2636); however, EGFR mutations were
significantly more frequent in females (36.6% vs. 19.6%, p=0.0019). No statistically significant differences were found
across disease stage, T, N, or M classifications (p>0.05). No association was identified between smoking status and EGFR
mutations (p=0.4178). Morphologically, EGFR mutations were significantly more prevalent in adenocarcinoma (54.83%)
compared to squamous cell carcinoma (SCC) (31.8%; p=0.002).
Of the 282 cases, adenocarcinoma accounted for 155 (54.9%) and SCC for 116 (41.1%). Overall, EGFR mutations were
positive in 43.97% of cases, with a higher prevalence in adenocarcinoma (24.82%) than in SCC (13.1%). By exon:
- Exon 18 mutations were detected in 6% of cases, predominantly in adenocarcinoma (6%, 4.25%).
- Exon 19 mutations occurred in 8.15% and are associated with sensitivity to targeted therapy.
- Exon 20 mutations were found in 3.19%, with the T790M resistance variant in 1.77%.
- Exon 21 mutations were observed in 9.57%, more common in adenocarcinoma (9.57%) than in SCC (3.19%).
Survival analysis stratified by stage at diagnosis showed significantly longer median survival in early-stage patients (18.6
months). Kaplan-Meier curve comparison, log-rank test, and hazard ratio calculations confirmed statistically significant
differences (p < 0.05), indicating that disease stage is a key prognostic factor.
Conclusion
The study findings reveal a high prevalence of EGFR mutations among Mongolian patients with lung adenocarcinoma,
underscoring the need for widespread implementation of targeted therapy (EGFR-TKIs). In contrast, mutation
rates were lower in SCC and other morphological subtypes, highlighting the importance of investigating alternative
molecular markers in these subgroups.
10.HER2 expression in patients with gastric cancer and Its clinical significance
Oyunchimeg N ; ; Undrakh O ; Naranzul S ; Dolgorsuren P ; Undarmaa T ; Gerelee Kh ; Adilsaikhan M ; Enkhjargal B
Mongolian Journal of Health Sciences 2025;90(6):112-119
Background:
Globally, gastric cancer accounts for 1,089,000 new cases and 769,000 deaths annually, ranking fifth in
overall cancer incidence and third in cancer-related mortality. The aim to determine HER2 expression in patients with
gastric cancer and to evaluate its correlation with clinical and immunological biomarkers, as well as the need for further
laboratory diagnostics.
Aim:
To determine HER2 expression in patients with gastric cancer and to evaluate its association with clinical and immunological
biomarkers, as well as the potential need for further laboratory diagnostics.
Materials and Methods:
A retrospective study was conducted using archived materials from patients with gastric cancer
at the Clinical Pathology, Molecular Genetics, and Pathology Laboratories of the National Cancer Center of Mongolia,
covering the period from 2019 to June 2025. HER2 protein expression in tumor tissue was assessed using immunohistochemistry
(IHC), and chromogenic in situ hybridization (CISH-HER2) was employed to confirm gene amplification.
Statistical analysis was performed using the Prisma-10 software.
Results:
In our study, among 210 cases of gastric cancer evaluated by IHC for HER2, 46 (21.9%) were HER2-positive
and 164 (78.1%) were HER2-negative. When comparing patients with gastric cancer stratified into HER2 1+ (negative)
and HER2 3+ (positive) groups, no statistically significant differences (p < 0.05) were observed in age, sex, tumor location
(surgically resected tissue), morphology, or disease stage. However, a higher proportion of males was noted in the HER2
3+ group (80.9%), though this did not reach statistical significance (p = 0.0879). Significant associations were found with
tumor markers. Elevated serum CA-72-4 (>5 ng/mL) was more frequent in the HER2 3+ group (58.8%; p = 0.0069). In
contrast, elevated CA-19-9 (>35 U/mL) was more common in the HER2 1+ group (93.5%; p = 0.0117), and elevated
CEA (>6.9 U/mL) was also predominant in the HER2 1+ group (90.6%; p = 0.002). These findings suggest that HER2 3+
status predominates in cases with elevated CA-72-4, which may influence diagnostic strategies and HER2-targeted therapies
(e.g., trastuzumab). Conversely, elevated CA-19-9 and CEA were more associated with HER2 1+ status, indicating
a need for further detailed investigation of these markers in relation to HER2 expression. In patients evaluated by CISH
for HER2 expression, stratification into HER2-positive and HER2-negative groups revealed no statistically significant
differences (p < 0.05) in age, sex, tumor location, morphology, stage, or serum tumor markers (CA-72-4, CA-19-9, CEA).
This suggests that HER2 status (positive/negative) may be independent of these variables. Although HER2 positivity was
higher in poorly differentiated tumors (48% vs. 30.6% negative; p=0.1414) and in stage IV disease (50% vs. 39.3% negative;
p=0.2607), these differences were not statistically significant. Elevated serum markers (CA-72-4, CA-19-9, CEA)
were observed but showed no significant correlation with HER2 status.
Conclusion
Determining the molecular profile of gastric cancer patients can significantly contribute to refining clinical
diagnosis, developing treatment strategies, enhancing therapeutic outcomes, and improving patients’ quality of life.
Result Analysis
Print
Save
E-mail