Gastrointestinal cancer in Iran

Epidemiologic Study of Gastric Cancer in Iran: A Systematic Review

BACKGROUND

Gastric cancer (GC) is one of the most common cancers in Iran. Knowledge of the epidemiology of the disease is essential in planning for prevention. So this study aimed to investigate the epidemiological aspects of gastric cancer including prevalence, incidence, mortality, and risk factors of Iran.

METHODS

This systematic review study was based on articles published in both English and Persian languages during the years of 1970-2020 in international databases (PubMed, Web of Science, Scopus) and national databases (including SID, Magiran, and IranDoc). Papers related to epidemiological aspects of the disease including mortality, prevalence, incidence, and risk entered the final review.

RESULTS

According to the studies, the minimum and maximum prevalence of gastric cancer in northwestern Iran (Ardabil) is between 0.2 and 100 per 100,000. Also, the death rate per 100,000 people ranged from 10.6 to 15.72 and the ASMR ranged from 4.2 to 32.2%. On the other hand, the incidence of GC was higher in men than in women (74.9 vs 4.6%). The GC risk ratio was 8-times higher in the elderly than in the other age groups (HR=8.0, 2.7-23.5). The incidence of gastric cancer in patients with H. pylori infection was 18-times and that of smokers 2-times higher than other populations. Low level of economic situation and food insecurity increased the odds of GC by 2.42- and 2.57-times, respectively. It should be noted that there was a direct relationship between consumption of processed red meat, dairy products, fruit juice, smoked and salty fish and legumes, strong and hot tea, and consumption of salt and gastric cancer incidence. There was also an inverse relationship between citrus consumption, fresh fruit, garlic, and gastric cancer. In addition, the mRNA genes are the most GC-related genes.

CONCLUSION

Given the high incidence of GC in Iran, changing lifestyle and decreasing consumption of preservatives in food, increasing consumption of fruits and vegetables, and improving the lifestyle can be effective in reducing the incidence of this disease.

Geographical spread of gastrointestinal tract cancer incidence in the Caspian Sea region of Iran: spatial analysis of cancer registry data

BACKGROUND

High incidence rates of gastrointestinal tract cancers have been reported in the Caspian region of Iran. This study aimed to: 1) describe the geographical spatial patterns of gastrointestinal tract cancer incidence based on cancer registry data and, 2) determine whether geographical clusters of statistical significance exist.

METHODS

The Babol Cancer Registry, which covers the two major northern Iranian provinces of Mazandaran and Golestan (total population = 4,484,622) was used to identify new gastrointestinal tract cancer cases during 2001 to 2005. Age-specific cancer incidence rates were calculated for 7 gastrointestinal tract cancer sites in 26 wards of the Mazandaran and Golestan provinces. Spatial autocorrelation indices, hierarchical Bayesian Poisson models, and spatial scan statistics were used in measuring the geographic pattern and clusters.

RESULTS

There were non-random spatial patterns in esophageal and stomach cancers that were similar for both sexes. Clusters of high incidence were identified in esophageal, stomach, colorectal and liver cancer for both sexes, as well as a possible cluster of pancreas cancer in males.

CONCLUSION

Gastrointestinal tract cancers exhibit significant spatial clustering of risk in northern Iran. Further work is needed to relate these geographical patterns to information on potential life-style and environmental factors.

Clinical profile of gastric cancer in Khuzestan, southwest of Iran

AIM: To analyze the characteristics of epidemiological, clinical and survival patterns among patients with carcinoma of the stomach.

METHODS: We retrospectively studied the characteristics of 186 gastric adenocarcinoma patients at Ahwaz Jundishapur University Hospitals (AJSUH) from September 1, 1996 to September 1, 2002. All the patients had histopathologically-confirmed malignancy. Demographic variables, family history of gastric cancer (GC), clinicopathologic characteristics and treatment-related variables were analyzed. Univariate analysis was performed with the log-rank test and multivariate analysis with Cox regression. P < 0.05 was considered statistically significant.

RESULTS: Male to female ratio was 2.6:1. The mean age was 60.6 years and 14% of the patients were younger than 40 years. Adenocarcinoma, gastric lymphoma, and gastric metastasis were found in 94.5%, 2.3%, and 3% patients, respectively. There was an average of 6-mo delay between the initial symptoms and the diagnosis. Among adenocarcinoma groups, intestinal type was the commonest (55.9%) and the distal third was the most common localization (88.4%). One hundred and thirty-four patients (72.1%) were males. Thirty-one patients (17%) had a family history of GC. Surgery was performed in 90% of patients (non-curative).

CONCLUSION: The epidemiological features of GC in south Iran mimic those in high-risk areas. There is a higher frequency of GC in young patients at our institution. Patients are detected and treated after a relatively long delay. Most patients present in advanced stages, which favors a poor overall survival. Family history of GC has a significant problem in our area. Studying the etiology of this cancer in south Iran and earlier diagnosis and subsequent better cares are recommended.

Hereditary risk factors for the development of gastric cancer in younger patients

BACKGROUND

It is believed that the development of gastric cancer (GC) before the age of 50 has a hereditary basis. Blood group A and history of gastric cancer in first-degree relatives have been shown to be risk factors for GC.

METHODS

In this case-control study, we enrolled patients with GC who were diagnosed before the age of 50. Patients who were diagnosed as having GC were selected. A total of 534 cases were found; of these, 44 diagnosed before the age of 50 were included in the case group. For the control group, 22 males and 22 females were randomly selected from the remaining subjects, who had diagnoses of GC after the age of 50. All the surviving patients and family members of the dead patients were interviewed about the history of cancer in the family and the age at which other family members developed cancer. The blood group of each subject was also obtained.

RESULTS

forty-four cases under 50 years old (mean age: 36.2 years) and forty-four controls (mean age: 67.1 years) were enrolled in the study. At the time of the study, 59.1% of the study group and 50% of the control group were alive (P value = NS). In the study group, 68.1%, 13.6%, 13.6% and 4.5% had blood groups O, A, B and AB, respectively. In the control group the corresponding figures were 27.7%, 63.6%, 6.8% and 4.5%. First or second-degree relatives with cancer, including gastric (the most frequent), breast, lung, gynecological and hematological malignancies, were noted in 54.5% of the cases and 11.4% of the controls (p < 0.01). Family histories of cancer were accepted as valid provided that they were based on valid medical documents.

CONCLUSIONS

It seems that the development of GC before the age of 50 is likely to be accompanied by familial susceptibility. Interestingly, our study showed a significant correlation between blood group O and the development of gastric cancer under the age of 50.

Cancer occurrence in Ardabil: results of a population-based cancer registry from Iran

The provincial health authority reported a high mortality rate from upper GI cancer in the newly established Ardabil Province of northwest Iran. A comprehensive search was undertaken to survey and register all cases of cancer during a 4-year (1996-1999) period among the indigenous population of Ardabil Province, including subjects seeking care in the cities of Tabriz and Tehran. Diagnosis of cancer was based on histopathology in 71.4%, clinical or radiologic findings in 25% and death certificate in 3.6% of cases. A total of 3,455 cancers (mean age 57.1 +/- 17.3 years) was found during the study. Of these, 60% (2,072) were in males. ASRs for all cancers in males and females were 132.0 and 96.3, respectively. The top 5 cancers in males (excluding skin cancer) according to the calculated ASR were stomach (49.1) [corrected], esophagus (15.4), lung and bronchus (7.9), colon and rectum (7.9) and bladder (7.6); in females, these were stomach (25.42), esophagus (14.4), breast (7.6), colon and rectum (5. 9) and lung and bronchus (3.6). Compared to rates obtained 30 years ago, the incidence of upper GI cancer in this region has increased about 100%, and there is a striking increase in the incidence of gastric cancer with a decline in the esophageal cancer rate. ASRs for gastric cancer in Ardabil were 49.1 for males and 25.4 for females, while for esophageal cancer these were 15.4 and 14.4, respectively. The ASR for cervical cancer was the lowest (0.4) recorded in the world before. Gastric cancer alone constitutes one-third of all cancers in Ardabil, the ASR of which is the highest reported from Iran up to now and one of the highest in the world.

Low Helicobacter pylori eradication rates with 4- and 7-day regimens in an Iranian population

BACKGROUND

In Iran, there is insufficient information on the efficacy of Helicobacter pylori eradication regimens shorter than 10 days. This study aims at assessing the efficacy of 4- and 7-day H. pylori eradication regimens in a high-incidence area of gastric cancer in Iran.

METHODS

Subjects with an endoscopic diagnosis of gastritis, positive urease test, and a histological diagnosis of chronic gastritis were enrolled. Patients were randomly assigned to one of three groups: AOC7 (1000 mg amoxicillin, 20 mg omeprazole, and 500 mg clarithromycin twice daily for 7 days), FOT4 (200 mg furazolidone, 20 mg omeprazole, and 500 mg tetracycline twice daily for 4 days) and FOT7 (the same treatment as the FOT4 group but for 7 days). Sensitivity to these antibiotics was determined in all isolates recovered from culture. The efficacy of eradication was assessed 8 weeks after the end-of-treatment by the 14C-urea breath test.

RESULTS

One hundred and twenty-eight patients were enrolled in the study. Culture was positive for 84 patients and none of these were resistant to amoxicillin, tetracycline or furazolidone, 1.2% were resistant to clarithromycin and 32.1% to metronidazole. Forty-five, 41 and 42 patients were randomly allocated to the AOC7, FOT4, and FOT7 groups, respectively. The intention-to-treat eradication rates were 35.5, 17.1, and 23.8% for the AOC7, FOT4, and FOT7 groups, respectively.

CONCLUSION

Treatment regimens of 4 or 7 days are unacceptable for H. pylori infection in Iran, even in the presence of a favorable sensitivity profile.

Cancer of the esophagus in southern Iran

The minimal yearly incidence of cancer of the esophagus in Fars Province in Southern Iran, based on hospital records in the capital city, is five to 10 times as high as the yearly incidence in Connecticut for the age group 15-44. Since these represent only a portion of cases among residents of the Province, the true rate is probably considerably higher. An unusual proportion of these cases (32% overall) presented with primary tumor in the upper third of the esophagus. The location of the tumor was related strongly to age, but not to sex after taking age into account. The proportion of esophageal cancer cases who were female was significantly greater than that of other GI tract cancers combined. It appears that the risk in males and females in this area is at least nearly equal, and risk could conceivably be higher in females (similar to the appearance of the disease in Northern Iran).

Primary upper small-intestinal lymphomal A report of 40 cases fron Iran

Primary upper small-intestinal lymphoma (PUSIL) has now been recognized as a distinct clinical entity with a distinct geographic distribution. Herewith are presented 40 cases of PUSIL seen at Pahlavi University Hospitals in Southern Iran. The investigation reveals the lymphoma to be predominantly a disease of those under 30 and males; the major complaints and physical findings point to an intraabdominal disease. An exception has been clubbing and osteoarthropathy. Special features of PUSIL include: (1) protein loss into the gastrointestinal tract leading to hypoalbuminemia and edema; (2) an antibiotic-responsive diarrhea and steatorrhea; and (3) an associated abnormal heavy-chain protein. The study further stresses the importance of peroral small-intestinal biopsy and the pathologic features of this condition.