Age Distribution of Lebanese Population* < % % % % % > %

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1 Age Distribution of Lebanese Population* Females Males Faour M, Saxena P, Naufal H, et.al " Demographic Estimates and Projections", The Population of Lebanon (2000) Age Group Percentage < % % % % % > %

2 Cancer Incidence in Lebanon 1993 Females (n=1387) Males (n=1469) Breast (38.6%) Bladder (18.6%) Colo-rectal (6.8%) Lung (15.0%) Copus Uteri (6.6%) Prostate (9.7%) Ovary (4.8%) Colo-rectal (8.7%) Cervix Uteri (4.6%) Larynx (7.0%) Stomach (4.5%) Stomach (4.6%) Lung (3.2%) Non-Hodgkin's Lymphoma (3.8%) Bladder (3.1%) Brain & nervous system (3.7%) Brain &nervous system (2.8%) Oro-pharyngeal (3.4%) Non- Hodgkin's Lymphoma (2.5%) Kidney and urinary tract (3.3%)

3 Cancer Incidence in Lebanon 1998 Females (n=2092) Males (n=2296) Breast (33.4%) Bladder (18.5%) Colo-rectal (8.7%) Lung (14.1%) Copus Uteri (4.8%) Prostate (9.7%) Ovary (4.3%) Colorectal (8%) Bladder (4.3%) Stomach (5.1%) Lung (4.3%) Larynx (4.8%) Cervix Uteri (4.2%) Brain & nervous system (3.9%) Brain &nervous system (3.9%) Kidney and urinary tract (2.7%) Stomach (3.6%) Non-Hodgkin's Lymphoma (2.7%) Thyroid (3.3%) Oro-pharyngeal (2.6%)

4 Comparison to national data Recently the Lebanese cancer epidemiology group has collected the first credible data on the Lebanese national incidence of cancer in 1993 and Compared to the national data, the number of patients treated at the AUBMC is round one third of all cancers treated in Lebanon. At the national level, in 1993 and 1998, the most frequent cases were breast cancer in females and bladder cancer in males for both years. Worldwide lung cancer remains the most common in males while bladder cancer ranks 7 th in frequency 1. In addition, there was a significant increase in the incidence of prostate cancer from 1993 to What follows is a relative comparison of the more frequent cancers at the national and medical center level: 1. Breast cancer: In our registry, breast cancer has accounted for 33% of all cancers and this is similar to the national data. The mean age is similar to the mean age of the patients at AUBMC (50.5 years). This is much lower than the mean age in developed countries like the USA (63.3 years). This mean that half of women in Lebanon will develop breast cancer to menopause and prior to the age of 50 which has a direct bearing on the age at which breast cancer screening should be started. The total number of cases at AUBMC have increased from 140 s to around 200 patients/year, moreover we have noticed that the percentage of patient diagnosed at an earlier stage (I & II)

5 with an accompanying increase in limited surgical procedures (lumpectomy and quadrantectomy as well as the introduction of sentinel node biopsy limiting the number of axillary dissection). World wide breast cancer remains the second most common cancer, and is the most common malignancy in females accounting for 22% of all cancers 1. Except for Japan, the highest incidence is seen in the most developed countries such as the USA, the Netherlands. The age-standardized rate in Lebanon is 38.9 per as compared to 89.2 in the USA, 56.1 in the UK, 66.2 in France, and 64.7 in Israel. The incidence of breast cancer is on the rise in most countries, in similar manner to what we have noticed. In many countries, this is directly related to an increase use of screening programs and a better awareness of breast cancer and its early signs. With time, this should translate into an earlier diagnosis at an earlier age. In Lebanon, screening programs are present in most academic centers. The mean age at diagnosis of breast cancer was comparable in 1993 and 1998 (52.1 and 52.8 years respectively). 2. Lung cancer: At AUBMC, lung cancer accounts for around 10-18% of all male cancers and the percentage has recently decreased (although the number of cases per year has remained around patients/year) despite a significant increase in the overall number of cancer s/year. In females, the number of lung cancer is on the rise in term of numbers and percentages as well, but accounts for only 4% of all female cancers. Lung cancers has been closely linked to tobacco smoking with some of the highest rates seen in the Middle East, China, the Carribean, South Africa, Zimbabwe and the Pacific for the less developed countries. National incidence rates closely reflect the history of tobacco smoking 2. In countries with a long history of smoking about 90% of cases of lung cancers are related to tobacco in men. In

6 women the relationship is less consistent 1. The trend in lung cancer incidence and mortality reflect the maturity of the smoking epidemic in various countries 3. Longer follow up are needed in Lebanon to determine whether these trends reflects maturity in the smoking epidemic. Certainly in women the trends is still increasing while in men many countries have reached this maturity. The agestandardized incidence of lung cancer in Lebanon in both males and females (18.7 and 5.1 per in 1988) is much less than that of countries such as the USA, UK, France (65-66 per ), and are closer to that of Israel and Algeria (28.5 and 14.5 per ). 3. Prostate cancer: At AUBMC, the number of prostate cancer has significantly increased since 1993 with around 88 seen in In a similar manner, at the national level, there was a significant increase in the crude incidence of prostate cancer from 1993 to 1998 (9.1 and 17.6 per respectively. This is due to a national campaign promoting screening for prostate cancer that started in This demonstrates the effectiveness of such national campaigns for screening for cancers that are potentially curable. However, the crude incidence in Lebanon is still very low compared to that in the USA where the incidence of prostate cancer is 104 per 10000, and it is the most common cancer in men. Survival is also better in the developed countries as compared to developing countries (80% Vs 40%) 1. It is still uncertain whether this will be reflected in improvement in survival or in the quality of life particularly in prostate cancers 1. However, in the USA the incidence of latent cancer started dropping after 1992, reflecting and exhaustion in the detection of these early cancers 4. A more in- depth review of patients with prostate cancer is needed to determine whether these cancers were detected at an earlier stage in 1998 than in The mean age of patients with prostate cancer diagnosed in 1993 and 1998 was similar (70.2 and 69.7 years respectively). Longer follow-up are need to determine whether this early detection will lead to a younger

7 mean age at diagnosis. Since the mean age of longevity for men in Lebanon is 68 years according to the last WHO report, then we should expect a continuous rise in the incidence before we reach maturity. 4 Bladder cancer: At AUBMC, bladder cancer accounts for around 7% of all male cancer. Bladder has also been linked to both tobacco and possibly to caffeine use. At the national level, bladder has always been the most common male cancer in Lebanon. Most studies previously found a positive relationship between bladder cancer and tobacco use with some studies showing a stronger relationship in women than in men 5.A small proportion of bladder cancer can be attributed to coffee drinking especially in nonsmokers 6 however both smoking and coffee cannot explain the unusually high incidence of bladder cancer in Lebanon. In countries like Egypt, a high infestation with Belharsia may explain the high incidence of bladder cancer, while in certain populations occupational exposures to paint components, polycyclic aromatic hydrocarbons, diesel exhausts, and aromatic amines may be related to a higher incidence of bladder cancer 7. However, none of these factors can explain why the incidence of bladder cancer is so high in our country. The agestandardized incidence in Lebanon parallels that of developed countries such France, the USA, and Israel, and is in contrast to the countries of the region such as Kuwait and Algeria. 5. Leukemia and Brain cancer:

8 With recent introduction of autologus bone marrow transplantation and the opening of the St Jude pediatric cancer center and the use of Gamma knife radiosugery, there was remarkable increase in the number of patients treated at AUBMC. The number of leukemia patients has significantly increased from 40 patients/yrs to 122 patients per year while the number of brain tumor has increased from 36/yr to 101/year due to the expansion in the neurosurgery service. This indicates that the introduction of advanced services will be followed by an increase in the number of patient treated at the medical center. At the national level we did not collect the incidence of leukemia because of technical difficulty in the collection of such cases, while the number of brain tumor patients has remained relatively constant. 5 Colorectal Cancer: Colorectal cancer is the third most frequent cancer worldwide for both males and females in incidence. Worldwide colorectal cancer incidence is high in North America, Western Europe, Australia, South America, Asia and Africa which may reflects differences in environmental exposures, presumably dietary 1. At the national level, the crude rates for colon cancer increased from 50.5 to 80.3/100,000 in males while rectal cancer decreased from to 40.4 to 18.5/100,000. In females, colon cancer increased from 14.9 to 60.2/100,000 while rectal cancer remained stable at 26.8 and 24.6/100,000. The age-standardized rates of colorectal cancers in Lebanon is less than in the USA, France, and Israel, but more common than in Kuwait and Algeria. On the other hand, rectal cancer is noted to be more common in females than in males, in almost all countries, including ours. Studies have shown that the risk of colon cancer is closely related to environmental changes 8. Recent studies have also shown that the risk of colon cancer may be decreased among recent postmenopausal hormonal replacement therapy users while rectal cancer was not 9. As in a many countries, the use of hormonal therapy in Lebanon has increased over the last few years, and this is in part due to a very successful campaign against

9 osteoporosis. In a recent meeting of the International Osteoporosis Foundation, the Lebanese Osteoporosis Society won the award for the most informed population on osteoporosis. Despite of this fact, the incidence of colon cancer has significantly increased in the Lebanese females from 1993 to 1998 while the incidence of rectal cancer remained stable. At AUBMC, the incidence of colon cancer, in both males and females has increased and it counts for around 4% of all cancers. Summary: At the national level, there was an overall increase in the crude rate of all cancers from 91.7 to per 100,000 in males and from 84.4 to per 100,000 in females. This may reflect a true increase in the overall incidence of cancer. However, this increase may also be due to an increase rate of detection of various cancers due to a marked improvement in the diagnostic capabilities of various medical institutions in Lebanon. Following the end of the civil war in Lebanon in 1990, there was a proliferation of in the number medical institutions as well as marked improvement and modernization of various medical diagnostic equipment. This is reflected in the presence of a large number of MRI, CT scan, mammogram suites, colonoscopy, cytology, pathology labs.disproportionate to the population. Moreover, there was a significant increase in the number of oncology specialist in the country from 2 oncologists in early nineties to around 80 in In addition, the increase crude rate of cancer may be due to the increase in the availability of modern and experienced medical care in remote areas of Lebanon which were previously heavily involved in the war such as the south of Lebanon. However, this is not reflected in the incidence reported from various areas because Lebanon is a small country and most cancer patients are treated in or around the capital Beirut. The overall increase in the crude rate of cancer was relatively more pronounced in females than in males with no clear etiology.

10 Several trends can be noted in term of the crude rates by sites. While the cause for the doubling in crude rate of prostate cancer from 1993 to 1998 may be attributed to the national screening/awareness campaign, this cannot explain the increase in the crude rate for bladder cancer in males from 17.2 to 21.4/100,000 and for the tripling of colon cancers in female 2.7 to 6.3/100,000. In contrast, the doubling of the crude rates for lung cancer for 2.5 to 4.8/100,000 in females may be attributed to an increase use of tobacco in the female population and specifically during the civil war. The increase in crude rate of brain tumors is more difficult to interpret, although there has been attempt to link it to an increase use of cellular phones, this has not been proven 10. A recent German study, however, found an excess of uveal melanoma in subject exposed to radio-frequency emitting devices (exposue to radio set OR 3.0, CI , cell phone OR 4.2, CI ) Epidemiology 2001;12:7-12, 1-4).