**3.5 Time trend of colorectal cancer mortality**

Between 2005 and 2018, the age-standardized mortality rate per 100,000 person-years (ASR-WHO) was increased from 3.4 to 9.8 in men and 2.2 to 3.9 in women (**Figure 4**). The significant increase trend was seen in both genders by 3.4% per year (**Table 3**). However, this significant increasing trend was observed in men only (5.2% per year, **Table 4**) but not in women (1.8% per year, **Table 5**).

### **Figure 4.**

*The trend of colorectal cancer mortality from 2005 to 2018 by gender in the Lang Son province located in North Vietnam. Missing data in 2009-2010; ASR-WHO: Age-standardized rate per 100,000 person-years using the World Health Organization standard population for 2000-2025.*



*The estimated proportion of deaths due to colorectal cancer was 0.82% (404 cases of colorectal cancer vs. 49,253 total cases), both genders.\$\$Adjusted for age group (0–9, 10–19, 20–29, 30–39, 40–49, 50–59, 60–69, 70–79, and 80+) and sex. Per year increment MRR (95% CI): 1.034 (1.010, 1.059), p = 0.005.*

*&Crude rate per 100,000 person-years.*

*\$ Age-standardized rate per 100,000 person-years using the World Health Organization standard population for 2000–2025.*

*# Proportion of death cases aged under 70 years. When combined for all cases from 2005 to 2018, for both genders, WHO-ASR: 5.8 per 100,000 person-years.*

### **Table 3.**

*Mortality due to colorectal cancer in both genders by year from 2005 to 2018 in Lang Son province.*


*The estimated proportion of deaths due to colorectal cancer was 0.64% (201 cases of colorectal cancer vs. 31,262 total cases) in men.##Adjusted for age group (0–9, 10–19, 20–29, 30–39, 40–49, 50–59, 60–69, 70–79, and 80+). Per year increment MRR (95% CI): 1.052 (1.017, 1.089), p = 0.003.*

*&Crude rate per 100,000 person-years.*

*\$ Age-standardized rate per 100,000 person-years using the World Health Organization standard population for 2000–2025.*

*# Proportion of death cases aged under 70 years. When combined for all cases from 2005 to 2018 in men, WHO-ASR: 6.9 per 100,000 person-years.*

### **Table 4.**

*Mortality due to colorectal cancer in men by year from 2005 to 2018 in Lang Son province.*

### **3.6 Screening for colorectal cancer and treatment**

Risk factors of colorectal cancer include certain unhealthy dietary regimens, precancerous lesions detected on colonoscopy, and genetic factors. According to the guideline for colorectal cancer diagnosis and treatment released by Vietnam's Ministry of Health in 2018, screening should be conducted on high-risk patients with a history of inflammatory bowel disease (Crohn's disease or ulcerative colitis) or colorectal polyps, or a family history of polyposis syndrome, colorectal polyps, or colorectal cancer. Fecal occult blood test (FOBT) and colonoscopy are pivotal in screening. During 2008–2010, the National Cancer Control Program organized a screening program for five malignant diseases in which 9634 people were screened for oral and colorectal cancer. However, stage I-II colorectal cancers accounted only for 32.2% [28].

**41**

*Colorectal Cancer in Vietnam*

*DOI: http://dx.doi.org/10.5772/intechopen.93730*

Treatment is decided based on multiple factors including staging, tumor location, and histopathology. Available treatment modalities in Vietnam are surgery,

*Age-standardized rate per 100,000 person-years using the World Health Organization standard population for* 

*Proportion of death cases aged under 70 years. When combined for all cases from 2005 to 2018 in women, WHO-*

**Year Case Crude rate& % < 70# ASR-WHO\$ MRR (95% CI)## p**

 11 3.0 63.6 3.2 1.545 (0.599, 3.986) 0.368 15 4.1 80.0 4.7 2.097 (0.855, 5.144) 0.106 17 4.5 35.3 4.9 2.344 (0.972, 5.652) 0.058 20 5.4 65.0 6.3 2.805 (1.186, 6.633) 0.019 29 7.7 62.1 8.8 3.994 (1.749, 9.117) 0.001 17 4.6 47.1 5.0 2.369 (0.982, 5.714) 0.055 24 6.1 45.8 7.0 3.159 (1.361, 7.332) 0.007 22 5.6 54.5 6.2 2.874 (1.228, 6.727) 0.015 15 3.8 66.7 4.3 1.965 (0.800, 4.818) 0.140 13 3.3 23.1 3.5 1.681 (0.670, 4.212) 0.268 13 3.3 61.5 3.9 1.704 (0.680, 4.272) 0.255 *The estimated proportion of deaths due to colorectal cancer was 1.13% (203 cases of colorectal cancer vs. 17,990 total cases) in women.##Adjusted for age group (0–9, 10–19, 20–29, 30–39, 40–49, 50–59, 60–69, 70–79, and 80+). Per* 

2005 7 1.9 57.1 2.2 1 (reference)

In terms of surgery strategy, it depends on the curative/non-curative approaches as well as the operation indication relates to the complications or not. Pham et al. (2020) conducted a study on patients who performed single-port laparoscopic right hemicolectomy. The mean survival time was 67.9 ± 3.3 months and the recurrence rate was 16.7%. The survival rates at 2, 3, and 5 years were 87.5, 79.9, and 66.7%, respectively. Survival was shown to be associated with age, tumor size, and TNM stage at 61.7 ± 3.9 months after treatment [30]. For advanced stages, three main agents were 5-fluoropyrimidines, oxaliplatin, and irinotecan, combined in common regimens including FOLFOX/XELOX, FOLFIRI/XELIRI, or FOLFOXIRI. Trinh et al. followed up with metastatic colon cancer patients treated with FOLFOXIRI. The mean disease-free survival time was 13.37 ± 9 months, with the response after 3 and 6 cycles being 82 and 79.4%, respectively [31]. Radiation therapy is indicated in

The surgery method for rectal cancer depends on the extent and location of the tumor [29]. Truong et al. conducted a cohort study during 2009–2016 on patients with low rectal cancer undergoing laparoscopic sphincter-saving resection. The local and distant recurrence rates were 10.4 and 20.8%, respectively. The overall survival was 52.7 ± 3.9 months and the disease-free survival was 38.3 ± 2.9 months [32]. In another study on rectal cancer patients who were treated with surgery, survival was reported to be associated with staging, lymph nodes metastasis, and tumor size. The mean overall survival time was 48.9 ± 52.7 months and the 3-year survival rate was 91.7%. Patients at stage I-II or having lymph nodes <10 mm in diameter had better prognosis [33]. Vi et al. conducted a study on metastatic rectal

radiotherapy, and chemotherapy (systemic and targeted) [29].

*Mortality due to colorectal cancer in women by year from 2005 to 2018 in Lang Son province.*

*year increment MRR (95% CI): 1.018 (0.985, 1.052), p = 0.294.*

*&Crude rate per 100,000 person-years.*

*ASR: 5.0 per 100,000 person-years.*

*\$*

*2000–2025. #*

**Table 5.**

patients who have metastatic lesions in the liver, bone, or lungs [29].


*The estimated proportion of deaths due to colorectal cancer was 1.13% (203 cases of colorectal cancer vs. 17,990 total cases) in women.##Adjusted for age group (0–9, 10–19, 20–29, 30–39, 40–49, 50–59, 60–69, 70–79, and 80+). Per year increment MRR (95% CI): 1.018 (0.985, 1.052), p = 0.294.*

*&Crude rate per 100,000 person-years.*

*\$ Age-standardized rate per 100,000 person-years using the World Health Organization standard population for 2000–2025.*

*# Proportion of death cases aged under 70 years. When combined for all cases from 2005 to 2018 in women, WHO-ASR: 5.0 per 100,000 person-years.*

### **Table 5.**

*Colorectal Cancer*

*\$*

*2000–2025. #*

**Table 3.**

**Year Case Crude** 

*&Crude rate per 100,000 person-years.*

*WHO-ASR: 5.8 per 100,000 person-years.*

**rate&**

*80+) and sex. Per year increment MRR (95% CI): 1.034 (1.010, 1.059), p = 0.005.*

**% < 70# ASR-WHO-\$ MRR (95% CI)\$\$ p**

2018 36 4.6 66.7 6.3 2.065 (1.146, 3.721) 0.016 *The estimated proportion of deaths due to colorectal cancer was 0.82% (404 cases of colorectal cancer vs. 49,253 total cases), both genders.\$\$Adjusted for age group (0–9, 10–19, 20–29, 30–39, 40–49, 50–59, 60–69, 70–79, and* 

*Age-standardized rate per 100,000 person-years using the World Health Organization standard population for* 

*Proportion of death cases aged under 70 years. When combined for all cases from 2005 to 2018, for both genders,* 

**Year Case Crude rate& % < 70# ASR-WHO-\$ MRR (95% CI)## p**

 12 3.3 75.0 4.7 1.311 (0.552, 3.112) 0.539 11 3.0 63.6 4.7 1.196 (0.496, 2.886) 0.691 14 3.8 57.1 5.4 1.501 (0.650, 3.468) 0.342 15 4.1 53.3 6.6 1.636 (0.716, 3.739) 0.243 18 4.8 55.6 7.8 1.928 (0.866, 4.290) 0.108 17 4.6 76.5 6.8 1.843 (0.821, 4.134) 0.138 23 5.9 65.2 9.6 2.354 (1.089, 5.089) 0.029 19 4.9 68.4 7.9 1.930 (0.873, 4.267) 0.104 26 6.7 69.2 10.1 2.649 (1.241, 5.654) 0.012 14 3.5 64.3 5.7 1.408 (0.609, 3.252) 0.424 23 5.9 69.6 9.8 2.346 (1.085, 5.070) 0.030 *The estimated proportion of deaths due to colorectal cancer was 0.64% (201 cases of colorectal cancer vs. 31,262 total cases) in men.##Adjusted for age group (0–9, 10–19, 20–29, 30–39, 40–49, 50–59, 60–69, 70–79, and 80+). Per* 

*Mortality due to colorectal cancer in both genders by year from 2005 to 2018 in Lang Son province.*

2005 9 2.5 88.9 3.4 1 (reference)

**40**

*\$*

*2000–2025. #*

**Table 4.**

**3.6 Screening for colorectal cancer and treatment**

*year increment MRR (95% CI): 1.052 (1.017, 1.089), p = 0.003.*

*&Crude rate per 100,000 person-years.*

*6.9 per 100,000 person-years.*

Risk factors of colorectal cancer include certain unhealthy dietary regimens, precancerous lesions detected on colonoscopy, and genetic factors. According to the guideline for colorectal cancer diagnosis and treatment released by Vietnam's Ministry of Health in 2018, screening should be conducted on high-risk patients with a history of inflammatory bowel disease (Crohn's disease or ulcerative colitis) or colorectal polyps, or a family history of polyposis syndrome, colorectal polyps, or colorectal cancer. Fecal occult blood test (FOBT) and colonoscopy are pivotal in screening. During 2008–2010, the National Cancer Control Program organized a screening program for five malignant diseases in which 9634 people were screened for oral and colorectal cancer. However, stage I-II colorectal cancers accounted only for 32.2% [28].

*Mortality due to colorectal cancer in men by year from 2005 to 2018 in Lang Son province.*

*Age-standardized rate per 100,000 person-years using the World Health Organization standard population for* 

*Proportion of death cases aged under 70 years. When combined for all cases from 2005 to 2018 in men, WHO-ASR:* 

*Mortality due to colorectal cancer in women by year from 2005 to 2018 in Lang Son province.*

Treatment is decided based on multiple factors including staging, tumor location, and histopathology. Available treatment modalities in Vietnam are surgery, radiotherapy, and chemotherapy (systemic and targeted) [29].

In terms of surgery strategy, it depends on the curative/non-curative approaches as well as the operation indication relates to the complications or not. Pham et al. (2020) conducted a study on patients who performed single-port laparoscopic right hemicolectomy. The mean survival time was 67.9 ± 3.3 months and the recurrence rate was 16.7%. The survival rates at 2, 3, and 5 years were 87.5, 79.9, and 66.7%, respectively. Survival was shown to be associated with age, tumor size, and TNM stage at 61.7 ± 3.9 months after treatment [30]. For advanced stages, three main agents were 5-fluoropyrimidines, oxaliplatin, and irinotecan, combined in common regimens including FOLFOX/XELOX, FOLFIRI/XELIRI, or FOLFOXIRI. Trinh et al. followed up with metastatic colon cancer patients treated with FOLFOXIRI. The mean disease-free survival time was 13.37 ± 9 months, with the response after 3 and 6 cycles being 82 and 79.4%, respectively [31]. Radiation therapy is indicated in patients who have metastatic lesions in the liver, bone, or lungs [29].

The surgery method for rectal cancer depends on the extent and location of the tumor [29]. Truong et al. conducted a cohort study during 2009–2016 on patients with low rectal cancer undergoing laparoscopic sphincter-saving resection. The local and distant recurrence rates were 10.4 and 20.8%, respectively. The overall survival was 52.7 ± 3.9 months and the disease-free survival was 38.3 ± 2.9 months [32]. In another study on rectal cancer patients who were treated with surgery, survival was reported to be associated with staging, lymph nodes metastasis, and tumor size. The mean overall survival time was 48.9 ± 52.7 months and the 3-year survival rate was 91.7%. Patients at stage I-II or having lymph nodes <10 mm in diameter had better prognosis [33]. Vi et al. conducted a study on metastatic rectal cancer patients who were treated with FOLFOX4 and bevacizumab. The median overall survival time was 19 months and the survival rates after 1 and 2 years were 56.9 and 27.6%, respectively. In this population, survival was associated with the CEA level, the number of organs having metastasis, histopathology, and response to bevacizumab [34]. The overall survival time in this study was similar to some studies using similar regimens in the world [35, 36].

## **3.7 Social health insurance and colorectal cancer control**

### *3.7.1 Health insurance in Vietnam*

Health insurance (HI) provides access to health examination and treatment for all patients, including those who cannot cover their medical expenses using out-of-pocket money, ensuring equity and social security. All public health establishments in Vietnam participate in the national health insurance scheme. Private hospitals, especially centers managing chronic diseases, are also encouraged to participate.

After enrolling in the national health insurance program, most of the general populations pay an annual amount of 1,117,000 VND (approximately 48.5 USD). Insurance fees can be waived for some special populations (e.g., poor households and veteran's relatives). In 2018, 86.8% of Vietnamese people are covered with national HI, allowing them to access most health-care services in Vietnam [37].

The mean direct costs for an outpatient and inpatient with colorectal cancer were 13.594 million VND (588 USD) and 63.371 million VND (2741 USD), respectively. This renders a financial burden for people who are not covered by HI and creates a barrier to access to health care [38]. As 80–100% of treatment costs for colorectal cancer are covered by HI in public hospitals and private clinics, patients enrolling in the insurance program can access expensive diagnostics and treatments. However, some targeted drugs and bevacizumab are only covered 30–50% by HI [39]. In Vietnam, the primary care levels are communal health stations and district health centers/hospitals. People who are treated at these facilities are fully covered if they participate in the HI program. If they must be transferred to higher-level (provincial/central) hospitals, patients have to present valid official letters of referral to the insurance agency to maintain maximum insurance coverage. The maximum coverage for a general person who is admitted to a central hospital is 80%; this will be reduced to 40% if they fail to present valid letters of referral [40].

### *3.7.2 Colorectal cancer control*

In Vietnam, a majority of colorectal cancer patients are detected at late stages. In a study in 2015, 67.8% of the patients were diagnosed at stage III/IV [28]. Early detection of colorectal cancer through screening may significantly increase the 5-year survival to 89.9%, compared with 13.8–71.1% in patients with regional and distant colorectal cancer metastasis [41].

Having acknowledged the situation, the Vietnamese Government issued the National Strategy for the Prevention and Control of Non-Communicable Disease (NCD) (2015–2025). One of the objectives of this strategy is to reduce late diagnosis and increase survival for colorectal cancer [42]. Colorectal cancer screening is conducted annually, supported by the National Cancer Control Program, and is accessible in many health-care facilities [28, 43]. For community screening, FOBT is applied in many health-care centers, with the advantage of being a noninvasive, quick, and reliable method. When the patients have positive FOBT, the next step to be performed would be colonoscopy. This strategy helps to screen mass population, especially the people with

**43**

*Colorectal Cancer in Vietnam*

*DOI: http://dx.doi.org/10.5772/intechopen.93730*

and encouraging physical exercises [46–48].

risk factors (family history, colon polyp history, or age), as well as save up the human and economic resources. Some preliminary data have shown the effectiveness of this approach in early colorectal cancer; however, the long-term benefits in national screen-

Efforts have been made to raise the awareness of lifestyle and diet modification, including limiting alcohol consumption and smoking, promoting a healthy diet,

A case-control study was performed for colorectal cancers admitted to Hanoi Cancer Hospital, Viet Duc Surgery Hospital, and Bach Mai General Hospital located in Hanoi. The ratio of case-control is 1:1 with the standards for matching are gender and age (±5). Cases and controls were interviewed to collect data in using demographic and lifestyle questionnaire and semiquantitative food frequency questionnaire. Blood samples were collected in the early morning on the day of operation [23, 24]. Most patients came from the provinces near Hanoi within the Red Delta

Distribution of blood ABO group in Vietnamese is 45.00, 21.20, 28.30, and 5.50% for types O, A, B, and AB, respectively [49]. In our study, the distribution is different, with 42.97, 23.67, 27.95, and 5.42% for types O, A, B, and AB, respectively [50]. The proportion of type A plus AB is 26.70% while type O plus B is 73.30% in Vietnamese. However, in our study, it is 29.10% and 70.90%, respectively. Distribution of blood ABO group in our study population is similar to that in Vietnamese. Blood ABO group was observed to be associated with cancer risk, whereas blood A was seen to increase the risk of stomach cancer in many studies [51]. Blood A, AB, and B have also increased the risk of pancreatic cancer [52]. In our study, blood type A plus AB was seen to increase the risk of colorectal cancer, with OR = 1.58, 95% CI = 1.05–2.38 [50] (**Table 6**). The mechanism of developing colorectal cancer in patients with blood types A and AB is unknown. When we separated colon and rectal cancer, the estimated risk was significantly increased for colon cancer, with OR = 3.36, 95% CI = 1.91–5.92, but not significantly increased for rectal cancer, with OR = 0.84, 95% CI = 0.54–1.32.

The function of CYP1A1 is recognized to be a major chemical carcinogeninduced cancer, in general, and colorectal cancer, in particular, in humans. We found that CYP1A1 (A/G and G/G genotypes) increased the risk of colorectal

When parents and close relatives suffered from cancer, the patients are at a higher risk of colorectal cancer, with OR = 3.00, 95% CI = 1.29–6.99, and OR = 3.63,

ing and management program requires bigger data from multicenters [44, 45].

**4. Risk factors and benefit factors of colorectal cancer in Vietnam**

**4.1 Performing case-control study on colorectal cancers**

River. They will be represented as Vietnamese in the north.

**4.2 Host factors related to colorectal cancer**

*4.2.2 CYP1A1 genotypes risk of colorectal cancer*

cancer, with OR = 1.86, 95% CI = 1.16–2.98 (**Table 7**) [50].

*4.2.3 Family and personal history of health and risk of colorectal cancer*

*4.2.1 Blood ABO group and risk of colorectal cancer*

### *Colorectal Cancer in Vietnam DOI: http://dx.doi.org/10.5772/intechopen.93730*

*Colorectal Cancer*

cancer patients who were treated with FOLFOX4 and bevacizumab. The median overall survival time was 19 months and the survival rates after 1 and 2 years were 56.9 and 27.6%, respectively. In this population, survival was associated with the CEA level, the number of organs having metastasis, histopathology, and response to bevacizumab [34]. The overall survival time in this study was similar to some

Health insurance (HI) provides access to health examination and treatment for all patients, including those who cannot cover their medical expenses using out-of-pocket money, ensuring equity and social security. All public health establishments in Vietnam participate in the national health insurance scheme. Private hospitals, especially centers managing chronic diseases, are also encour-

After enrolling in the national health insurance program, most of the general populations pay an annual amount of 1,117,000 VND (approximately 48.5 USD). Insurance fees can be waived for some special populations (e.g., poor households and veteran's relatives). In 2018, 86.8% of Vietnamese people are covered with national HI, allowing them to access most health-care services in Vietnam [37]. The mean direct costs for an outpatient and inpatient with colorectal cancer were 13.594 million VND (588 USD) and 63.371 million VND (2741 USD), respectively. This renders a financial burden for people who are not covered by HI and creates a barrier to access to health care [38]. As 80–100% of treatment costs for colorectal cancer are covered by HI in public hospitals and private clinics, patients enrolling in the insurance program can access expensive diagnostics and treatments. However, some targeted drugs and bevacizumab are only covered 30–50% by HI [39]. In Vietnam, the primary care levels are communal health stations and district health centers/hospitals. People who are treated at these facilities are fully covered if they participate in the HI program. If they must be transferred to higher-level (provincial/central) hospitals, patients have to present valid official letters of referral to the insurance agency to maintain maximum insurance coverage. The maximum coverage for a general person who is admitted to a central hospital is 80%; this

will be reduced to 40% if they fail to present valid letters of referral [40].

In Vietnam, a majority of colorectal cancer patients are detected at late stages. In a study in 2015, 67.8% of the patients were diagnosed at stage III/IV [28]. Early detection of colorectal cancer through screening may significantly increase the 5-year survival to 89.9%, compared with 13.8–71.1% in patients with regional and

Having acknowledged the situation, the Vietnamese Government issued the National Strategy for the Prevention and Control of Non-Communicable Disease (NCD) (2015–2025). One of the objectives of this strategy is to reduce late diagnosis and increase survival for colorectal cancer [42]. Colorectal cancer screening is conducted annually, supported by the National Cancer Control Program, and is accessible in many health-care facilities [28, 43]. For community screening, FOBT is applied in many health-care centers, with the advantage of being a noninvasive, quick, and reliable method. When the patients have positive FOBT, the next step to be performed would be colonoscopy. This strategy helps to screen mass population, especially the people with

studies using similar regimens in the world [35, 36].

*3.7.1 Health insurance in Vietnam*

aged to participate.

*3.7.2 Colorectal cancer control*

distant colorectal cancer metastasis [41].

**3.7 Social health insurance and colorectal cancer control**

**42**

risk factors (family history, colon polyp history, or age), as well as save up the human and economic resources. Some preliminary data have shown the effectiveness of this approach in early colorectal cancer; however, the long-term benefits in national screening and management program requires bigger data from multicenters [44, 45].

Efforts have been made to raise the awareness of lifestyle and diet modification, including limiting alcohol consumption and smoking, promoting a healthy diet, and encouraging physical exercises [46–48].
