Comparison of cancer incidence in Iran and Iranian immigrants to British Columbia, Canada.

Migrant studies provided strong evidence about the role of environment and life style in cancer risk. Iran has experienced many immigrants to other countries with different cultures and environment. This study compares cancer incidence rates in Iran, Iranian immigrants to British Columbia (BC), Canada, and the BC general population. Cancer incidence rates were computed from two population-based cancer registries in Iran and from the BC cancer registry. A listing of common Iranian surnames and given names was produced to identify Iranian immigrants within the BC cancer registry. Age-standardized rates (ASRs) were calculated using mid year census data. The overall cancer incidence rate for Iranian female immigrants was intermediate between rates for Iran and the BC general population, and the rate for Iranian male immigrants was lower as compared to the other population groups. For female Iranian immigrants, the incidence of breast cancer was increased four-fold, and for colorectal cancer two-fold, as compared to Iranian rates. A dramatic decrease was found in the incidence of both stomach and oesophageal cancers for Iranian immigrants of both sexes. For male Iranian immigrants, the incidence of prostate cancer was increased as compared to Iranian rates. Differences in incidence rates of specific cancers were observed between BC Iranian immigrants and Iran, with cancer patterns in Iranian immigrants being more similar to the BC general population. This warrants further investigation into differences in lifestyle and cancer detection.

Cancer occurrence in Iran in 2002, an international perspective.

For almost 30 years no population-based cancer statistics have been available with which to estimate the cancer burden in Iran. In 2002 and 2003 two separate reports of population based cancer registries were published from Iran and the cancer incidence rates from these sources have permitted informed estimates of cancer incidence and mortality to be prepared. They suggest that more than 51,000 cases of cancer are diagnosed and 35,000 deaths due to cancer occur each year. The 5 most common cancers in males (by ASR) are stomach (26.1 per 10(5)), esophagus (17.6 ), colon-rectum (8.3), bladder (8.0) and leukemia (4.8), and in females are breast (17.1), esophagus (14.4), stomach (11.1), colon-rectum (6.5) and cervix uteri (4.5). The incidence rates of esophageal and stomach cancer in Iran are high, well above the world average, while the incidence of lung cancer is very low. Breast cancer, although the most common cancer of females in Iran, has rates that are low by world standards, especially those observed in Europe and USA. Similarly, the incidence of cervix cancer in Iran is very low, even lower than such low risk countries as China, Kuwait and Spain. Comparing these rates with the data of 30 years ago, the incidence of esophageal cancer has decreased dramatically, but gastric cancer has increased about two fold.

Peptic ulcer bleeding: is Helicobacter pylori a risk factor in an endemic area?

BACKGROUND/OBJECTIVE: A high prevalence of Helicobacter pylori infection has been reported in Iran. Although the importance of H. pylori in the induction of peptic ulcer disease is clearly defined, only few studies have addressed its role in bleeding from peptic ulcers. We evaluated the role of H. pylori in peptic ulcer bleeding. METHODS: Patients with acute peptic ulcer bleeding (PUB) and those with peptic ulcer disease without bleeding ('controls') were enrolled. Upper GI endoscopy and rapid urease test were performed in both groups. Histological study for detection of H. pylori was performed in patients with active bleeding, if RUT was negative. Other variables evaluated included sex, age, smoking, previous history of bleeding, non-steroidal anti-inflammatory drugs use, ulcer size, ulcer location, and duration of acid-peptic disease. Multivariate logistic regression analysis was performed to identify independent risk factors. RESULTS: 161 patients with PUB and 287 control patients were enrolled. H. pylori infection was seen more frequently in patients with duodenal ulcer than gastric ulcer (88.9% vs. 60.5%, p< 0.001). Univariate analysis showed that patients with PUB were more often male, older in age, used NSAID, had history of PUB in the past, had ulcer located in the stomach and not in the duodenum, and more often had large ulcer (>1 cm). Logistic regression analysis showed that H. pylori infection was protective in PUB after controlling for confounders (OR 0.41, 95% CI 0.21-0.79), when ulcer location was not entered in the model. A second model including ulcer location (to test for a residual effect) showed that H. pylori infection was not a significant risk factor in PUB (OR 0.61, 95% CI 0.30-1.24). CONCLUSIONS: H. pylori may not be an independent factor in bleeding from peptic ulcers. The lower frequency of this infection in these patients can be described by the higher frequency of bleeding from gastric ulcers, which are less H. pylori related compared with duodenal ulcer.