Pattern of Cancer in Saudi Arabia: A Personal Experience Based on the Management of 1000 Patients.
1982; King Faisal Specialist Hospital and Research Centre; Volume: 2; Issue: 4 Linguagem: Inglês
10.5144/0256-4947.1982.203
ISSN0975-4466
Autores Tópico(s)Colorectal and Anal Carcinomas
ResumoOriginal ArticlesPattern of Cancer in Saudi Arabia: A Personal Experience Based on the Management of 1000 Patients.Part 1 Majid H. AmerMD, FRCS(ED), FRCP(C), FACP Majid H. Amer Oncologist, Department of Oncology, King Faisal Specialist Hospital and Research Centre Search for more papers by this author Published Online:1 Oct 1982https://doi.org/10.5144/0256-4947.1982.203SectionsPDF ToolsAdd to favoritesDownload citationTrack citations ShareShare onFacebookTwitterLinked InRedditEmail AboutABSTRACTABSTRACTBetween October 1978 and December 1981, 1000 consecutive patients with cancer referred to the King Faisal Specialist Hospital and Research Centre were seen and treated by one oncologist. There were 581 men and 419 women with a median age of 50 years. Two hundred and fifty-three (25 percent) patients had gastrointestinal malignancies, 231 (23 percent) malignant lymphoma, 184 (18 percent) head and neck cancer, 105 (11 percent) sarcomas, 104 (10 percent) gynecologic malignancies, and 52 (5 percent) breast cancer.The commonest tumors among male patients were gastrointestinal cancer, non-Hodgkin's lymphoma and head and neck cancer, while gynecologic malignancies, non-Hodgkin's lymphoma and gastrointestinal neoplasms were more common in females. The incidence is somewhat different from Western countries. Possible etiological factors which may contribute to such differences are discussed. Most patients were seen in far advanced stages of disease. Seventy-six percent of relatively poor patients present to their physicians with far advanced Stage III and IV disease, compared to 67 percent of patients with middle or high socioeconomic status (p<0.05) and after a mean duration of 10.3 months compared to 8.6 months (p<0.02). Patients with esophageal cancer or non-Hodgkin's lymphoma present to their physician earlier, the majority with Stage I or II disease, compared with patients suffering from head and neck or gastrointestinal malignancies. Definite improvement was noted in cancer detection during the past four years in Saudi Arabia. The mean interval between initial symptoms and clinicopathologic diagnosis decreased from 13.1 months in 1977 to 7.5 months in 1981 (p <0.001). Patients with Stage I or II disease accounted for 15 percent of cancer cases during 1978 compared with 45 percent during 1981 (p < 0.05). Such improvement is most likely attributed to the economic development in Saudi Arabia, and particularly to the vast expansion in health care facilities.INTRODUCTIONKing Faisal Specialist Hospital and Research Centre (KFSH), a 250-bed referral hospital, is the main cancer treatment center in Saudi Arabia, with over 1300 new cancer referrals a year. Over the past three years, 1000 consecutive patients with cancer were seen and treated at this Hospital by one oncologist. Experience in their management forms the basis of this study. Such information gives some insight into cancer in Saudi Arabia and may be helpful in future planning of a comprehensive cancer campaign.MATERIALS AND METHODSKing Faisal Specialist Hospital and Research Centre is a multispecialty referral hospital with an average of 13,500 new patients referred each year. The Oncology Department at the Hospital consists of three divisions, Medical Oncology, Radiation Therapy, and Pediatric Oncology. Most adult patients with cancer referred to the Hospital are seen at the medical oncology clinics, while pediatric cancer patients are initially referred to pediatric oncology clinics.Between October 1978 and December 1981, 1844 patients with cancer were referred to the medical oncology clinic. This service was manned by the author and two other consultants with different oncologic interests. One consultant was mainly interested in leukemias (180 patients), lymphomas (70), multiple myelomas (15), as well as others (49); while the second consultant was limiting his practice to breast cancer (100), lymphomas (80), hepatomas (60), genitourinary neoplasms (80), lung cancer (40), central nervous system tumors (40), as well as others (130).The material of this study consisted of 1000 adult patients with cancer seen only by the author during the interval between October 1978 and December 1981. Seventy-five patients (0.8 percent) were non-Saudi and the rest (99.2 percent) were of Saudi nationality. Among non-Saudi patients, 61 were residents of Saudi Arabia for over five years and were considered as Saudi, while 14 patients were referred from other Middle Eastern countries and were analyzed separately.Only patients with histologically proven malignancy were included in this study. All patients had a detailed clinical examination and laboratory tests which included a complete blood count, multiphasic blood chemistry screen and chest radiograph. Most patients had radionucleotide liver and bone scanning, and a few had computerized tomographic whole body scanning.Age was defined at the time of initial diagnosis. Residency location referred to one of the five main provinces in Saudi Arabia. The Central Province includes Riyadh, Buraidah, Eniza, Kharj, Dawadmi, and Aflag. Medina, Yanbu, Jeddah, Makkah, Taif, and Baha are included in the Western Province, while Hail, Tabuk, Ar Ar, and A1 Jouf are the main cities in the Northern Province. Southern Province includes Abha, Bishah, Najran, and Jizan. Damman, Hafouf, and Qatif are included in the Eastern Province.Patients of low socioeconomic status were defined as those with a gross yearly income of less than 7000 Saudi riyals (equivalent to $2000) and included some Bedouin farmers and unemployed persons. Patients living in small houses or tents, without electricity or clean running water, were included in the low socioeconomic grouping even if their income exceeded the above figure. Patients with middle socioeconomic status were defined as those with a gross yearly income of over 7000 Saudi riyals but less than 200,000 Saudi riyals (equivalent to $60,000). Those with higher incomes were included among those of high socioeconomic status.Interval to clinical diagnosis was defined as the duration, in months, between initial symptoms and clinicopathological diagnosis of cancer. At the time of initial diagnosis, regardless of hospital location, all patients were staged according to the American Joint Committee for Cancer Staging and End Results Reporting 1980 guidelines. Patients with Hodgkin's and non-Hodgkin's lymphomas were staged separately according to the Ann Arbor Staging Classification. When these classifications were not applicable, such as in hepatocellular carcinoma and bone tumors, they were considered Stage I when their disease was localized, Stage II when regional lymph nodes were involved, Stage III when the disease was far advanced locally or regionally, and Stage IV when there was evidence of distant metastases.The chi-square statistical test with one degree of freedom was used to differentiate between two or more variables, while the Student f-test (in two tails of the t-distribution and df =n — 2) was used to differentiate between different means.RESULTSThe pattern of patient age in relation to sex is illustrated in Figure 1. Patient distribution according to primary tumor site and in relation to age, sex and social status is illustrated in Table 1. Patients with gastrointestinal malignancies accounted for 25.3 percent of all patients and included 64 (25 percent) gastric cancer, 60 (24 percent) esophageal tumors, 51 (20 percent) colonic cancer, 37 (15 percent) pancreatic neoplasm, 30 (12 percent) hepatomas, and 11 (4 percent) gallbladder cancer. Of 64 patients with gastric cancer, 36 (56 percent) were of low economic status while 28 (44 percent) were in the middle or high economic group.Figure 1.: Age-sex relationship. Top numbers show totals in each age group.Download FigureTable 1. Primary tumor site in relation to age, sex and social statusTable 1. Primary tumor site in relation to age, sex and social statusMalignant lymphomas ranked as the second commonest malignancy. Twenty-three percent of patients had either Hodgkin's disease (37) or non-Hodgkin's lymphoma (194). Patients with head and neck cancer accounted for 18.4 percent of all patients in this series and included 65 (35 percent) patients with nasopharyngeal carcinomas, 48 (26 percent) with intraoral cancers, 26 (14 percent) with either pharyngeal (15 patients) or laryngeal (11 patients) tumors, and 16 (9 percent) thyroid neoplasms. Among patients with gynecologic malignancies 58 (56 percent) had ovarian cancers, 25 (24 percent) trophoblastic disease, eight (8 percent) uterine neoplasms, and 13 (13 percent) carcinoma of the cervix.Two sisters and one brother had familial xeroderma pigmentosum and skin cancer, while six brothers belonging to three separate families had nasopharyngeal carcinomas. Another 32 patients gave histories of familial cancer. The smoking habit was uncommon among our patients. Only 122 (12 percent) patients were smokers. Ten patients with head and neck cancer admitted to the habit of chewing betel nuts, while nine patients indicated heavy alcoholic intake.Factors which may influence the interval to diagnosis and initial stage of disease are illustrated in Table 2. Elderly patients and women present themselves to their physician later. There is also a trend for patients over 60 years of age to present with far more advanced disease than young patients (p>0.05). Patients of low socioeconomic status usually presented late, mostly in Stage III or disease, compared to those with middle or high income (p 0.05).Table 2. Factors influencing the interval to diagnosis and initial stage of diseaseTable 2. Factors influencing the interval to diagnosis and initial stage of diseaseDISCUSSIONIncidence of CancerThe occurrence of cancer in Saudi Arabia cannot be measured statistically on a national basis. The incidence is not available because a national cancer registry has not been established. In addition, most patients are treated in private clinics or hospitals that do not maintain such records. Any information on cancer incidence must, therefore, be interpolated from the experience in the management of cancer patients at hospitals that deal primarily with such treatment. However, such information is not as accurate as information from an established cancer registry record. It is imperative to stress the fact that a National Cancer Registry program is an essential part of any cancer campaign, and all efforts should be made to establish such a system in Saudi Arabia.In this series, gastrointestinal malignancies were the leading malignant neoplasms in males (23 percent) followed by non-Hodgkin's lymphoma (22 percent) and head and neck cancers (22 percent). Among women, gynecologic malignancies accounted for 25 percent of patients, followed by non-Hodgkin's lymphoma (15 percent), gastrointestinal tumors (14 percent), and head and neck cancers (13 percent). Although such percentages represent a personal experience biased by the author's preference in disease selection, and accordingly they do not represent the overall incidence of cancer in Saudi Arabia, they may indicate that gastrointestinal malignancies (25 percent), malignant lymphomas (22 percent) and head and neck cancers (18 percent) are relatively common diseases in Saudi Arabia. Similar observations were noted by Stirling and his colleagues.1 In their report on 1000 patients from the Western Province of Saudi Arabia, head and neck cancers accounted for 21.2 percent of all tumors, followed by gastrointestinal malignancies (16.2 percent), skin cancer (15.5 percent), lymphomas (12.8 percent), gynecologic tumors (10.3 percent), breast cancer (7.4 percent), sarcoma (7.3 percent), genitourinary neoplasms (5.1 percent), and lung cancer (4.2 percent). Such distribution is distinctively different from Western countries where gastrointestinal malignancies, lung neoplasms and skin cancers account for most tumors in males while breast cancers, gastrointestinal malignancies and gynecologic neoplasms are the commonest tumors in females. By comparison, malignant lymphomas and head and neck cancers, which are common in Saudi Arabia, are relatively rare among Western populations. Possible etiological factors which may contribute to such differences will be discussed.Possible PathogenesisExtensive epidemiological and experimental evidence has implicated environmental factors in the pathogenesis of most types of human malignancies. Interest in and concern about such factors have been steadily increasing in both the scientific and lay communities. In Saudi Arabia there is no study which correlates individual forms of cancer with occupational histories, food habits, history of drug use and environmental conditions. Such information would be helpful in the future planning of a comprehensive cancer campaign. In this series we will correlate certain malignancies with some epidemiological factors pertinent to Saudi Arabia. However, one has to stress the fact that the following discussion is mainly a personal impression of possible factors which may predispose to cancer in Saudi Arabia. Further investigations are needed in order to confirm or refute these assumptions. It is also important to indicate the multifactorial etiology of many human cancers, the importance of low-dose carcinogen exposure and the role of carcinogenesis in the promotion of human cancer.Genetic factorsWhile there are many specific genetic disorders that increase the individual's risk for specific cancers, their overall number is relatively small. Most of the genetic influences appear to relate to a secondary effect and are often also interrelated with familial factors of etiologie significance. In this series, familial cancer accounted for a small percentage of patient referral.Role of virusesThe association of various viruses with cancer in humans is based, in part, upon the early studies of Rous, Marek, Shope, Lucke, and Gross in which naturally occurring neoplasms in chickens, rabbits, frogs, and mice were found to follow virus infection. Of the human viruses studied to date, the strongest associations are represented by Epstein-Barr virus (EBV) and Burkitt's lymphoma as well as nasopharyngeal carcinoma, and hepatitis B virus and liver cell carcinoma.Burkitt's lymphoma. Results of extensive prospective seroepidemiologic studies strongly suggest that a causal relationship exists between EBV and the development of Burkitt's lymphoma, as all children developing the disease had been exposed to the virus at an early stage and had markedly elevated antibody titers to EBV prior to tumor development.2,3 Recurrent malaria appears to be the primary promotor since it dramatically alters the immune system of children already infected with EBV. Burkitt's lymphoma is not common in high EBV-infected areas where malaria is not present.In Saudi Arabia, nine patients with Burkitt's lymphoma, treated at King Faisal Specialist Hospital, were referred from the Southern Province where malaria is common.4 Many patients with non-Hodgkin's lymphoma in this series were also referred from the Southern Province near Yemen. Figure 2. There are no reported data relating EBV, or any viruses, to non-Hodgkin's lymphoma; however, such distribution deserves further investigation to confirm or exclude such possibilities.Figure 2.: Geographical distribution of patients with non-Hodgkin's lymphoma in Saudi Arabia.Download FigureNasopharyngeal carcinoma (NPC) is a common malignancy among the Chinese population in Southern China and Singapore. Some studies have demonstrated the presence of EBV genetic information in the tumor.2In this report, NPC is a common disease, accounting for 26 percent of all head and neck cancer patients. Six patients belonging to three separate families had NPC. Another five patients gave histories of close contact with other patients who had NPC. Further investigations are needed to define the role of EBV in nasopharyngeal carcinoma.Hepatitis B virus infection has been linked to hepatocellular carcinoma by seroepidemiological evidence.5,6 A prevalence of indicators of active hepatitis B infection has been demonstrated, particularly surface antigen and antisurface antigen antibody, in patients with primary hepatocellular carcinoma as compared to matched controls and with the general population.A report on hepatocellular carcinoma in Saudi Arabia indicates that of 54 patients treated at this Hospital, 30 (55 percent) had positive hepatitis B surface antigen, which was higher than matched controls (18 percent) or general population (8 percent).7Air pollution and occupational hazardsThere is overwhelming evidence that prolonged and heavy exposure to any one of several different types of air contaminants increases the risk of cancer. Examples of contaminants include: tobacco, smoke, benzo(a)pyrene, vinyl chloride, radon gas, and dust composed primarily of asbestos fibers, radioactive materials, and chromates.In this report, only a small percentage of patients were smokers, and none of these patients was persistently exposed to such air contaminants. This may explain the rarity of lung cancer in our patient population as well as other reports.1 With the increase in smoking habits among the younger population and a greater drive toward industrialization, it is anticipated that more patients with lung cancer will be diagnosed during the next decade. All efforts should be made to discourage people from smoking.Ultraviolet radiationThere is extensive evidence that skin cancer, at least of the nonmelanotic type, is primarily caused by cumulative exposure to ultraviolet radiation (UV). The cumulative dose of exposure to UV radiation in sunlight is a function of the amount of ozone in the stratosphere, atmospheric conditions (cloudiness, extent of damage from aerosols, etc.), latitude and life style, which includes time and type of outdoor activity. Approximately 60 percent of the day's total carcinogenic radiation is received between 10 a.m. and 2 p.m. The relative effect of avoiding sunlight during this time is significantly large. By avoiding just one hour from 12 noon to 1 p.m. one can receive 25 percent less exposure. By avoiding two noontime hours, one can achieve a 35 to 50 percent reduction of UV exposure.8Because of clear skies and lack of rain in most areas of Saudi Arabia, it is possible that a large percentage of persons will have skin cancer. However, only a small number of patients in this series had such disease. Such findings may be due to a bias in patient referral, as patients with early stages of skin cancer are treated successfully at their local hospitals without being referred to King Faisal Specialist Hospital. This was obvious in one study from the Western Province where skin cancer accounted for 15 percent of all cancer patients.1 On the other hand, the overall incidence of skin cancer in Saudi Arabia may be low. Saudi men always wear headdress, the khutra, and in the case of women, the veil, which give some protection against UV light. The longstanding Saudi custom of staying indoors during the noontime period, avoiding sunlight, may also be a factor.Personal habits and exposure to carcinogensSix patients (two men and four women) with conjunctival carcinoma admitted the use of locally made kohl over their eyelashes for years preceding the development of their cancers. Kohl is made of ash remnant from burning kerosene and gum arabic in addition to powder derived from ground black stones. It is possible that some of these materials are carcinogenic, and their persistent use may lead to such disease.Drinking waterConcern over the contamination of drinking water has been focused on that caused by viruses, bacteria, and parasites. However, the organic chemical contaminants, and to a lesser extent, the inorganic chemicals may be important in causing cancer.9–13In Saudi Arabia, water resources vary widely in quality and quantity. There are several cities such as Buraidah, Qatif, and Tabuk, where, in spite of the abundance of water, improperly drilled private wells for water supply or sewage drainage create difficulties. Other areas such as Wajh, Diba, some of the Arabian Shield, and Assir are suffering either from lack of water or absence of good quality water.14 Until recently, most drinking water in Saudi Arabia was unpurified, and, except in large metropolitan areas, it is untested for contamination. Although one cannot say for sure that such contamination causes cancer directly, the probability remains that these ingested water contaminants may contribute in some form or another to the total cancer burden.Dietary factorsIn several studies dietary variables were found to be strongly correlated geographically with several types of cancer. In one report based on a number of considerations, as much as 50 percent of common cancer was attributed to dietary factors.15 Cancer of the breast, corpus uterus, and colon has now been found to be strongly associated with total protein and fat consumption, particularly meat and animal fat, while gastric cancer and possibly head and neck cancer have been related to malnutrition, especially the lack of vitamins.Gastric cancer. Reduction in the incidence and mortality from stomach cancer has been occurring in most countries for several decades. These changes have been correlated with changing dietary practices.16 The relevant factors probably include increased use of refrigeration and increased consumption of milk, green vegetables, and fruits. The relevant mechanism may be a greatly reduced opportunity for the production of nitrosamines in the gastric contents and possibly reduced exposure to other carcinogens in food.17In Saudi Arabia, the main diet consists of cereal products, lamb meat, and milk but rarely fresh vegetables or fruits (except dates). This is more pronounced in patients of low socioeconomic status who cannot afford to purchase fruits or vegetables more often than once each week. The low level of vitamin intake, especially vitamins C and A, may decrease the effectiveness of the gastric mucosal barrier against mutagens. Ingestion of carcinogenic factors in diet or via contaminated water, even when such intake is intermittent or periodic, may be an important factor in promoting the occurrence of gastric cancer.In this series, gastric cancer accounted for one-fourth of gastrointestinal malignancies. Of 64 patients, 36 (56 percent) were of low socioeconomic status, living in small, rural communities away from modern water purification plants or vegetables and fruit farms.Colon cancer. Recent evidence relates two groups of nutrients, fat and fibers to colon cancer. High fiber content diets reduce the incidence of malignancy, while increasing dietary fat promotes cancer.19,20 One hypothesis suggests that fibers, as those in cereal bran, possibly absorb bile acids and as yet other unidentified carcinogens, thus reducing the fecal concentration of substances that may act as promotors of cancer.20 On the other hand, a high fat diet increases fecal bile acid excretion and promotes cancer.In this study, patients with colon cancer accounted for 5 percent of all malignancies. Such low incidence may be attributed to the low fat consumption among Saudis.Esophageal cancer. Esophageal tumors occur with a wide range of frequency in different geographic areas. They are rare in the United States but common in other areas, particularly in a broad belt across central Asia.21 The high rate of esophageal cancer among certain African groups has been ascribed to the locally brewed maize beer which is thought to be contaminated with nitrosamines or substances that are converted into nitrosamines in the stomach.22,23 On the other hand, a 30-fold gradient in disease incidence exists along a small strip of several hundred kilometers near the Caspian Sea.24 Such variation cannot easily be attributed to the amount of alcohol consumed, which suggests that other factors besides alcohol consumption have important functions.25In this study, none of our patients admitted the intake of alcohol. One-half of these patients were of low economic status and possibly other factors may be responsible.Head and neck cancer. Alcohol and tobacco are both risk factors for cancer of the mouth and pharynx.26 Heavy drinkers experience a risk two to six times greater than nondrinkers. The combined effect of heavy smoking and drinking results in a risk more than 15 times greater than for those who neither smoke nor drink, whereas heavy smoking alone results in no more than a two- to three-fold increase in risk.Among 184 patients with head and neck cancer in this study, only 30 were heavy smokers and three admitted the consumption of alcohol. On the other hand, 123 (68 percent) were of low economic status and the majority were either Bedouin or farmers. Most patients were referred from the Southern Province. Figure 3. It is possible that nutritional factors, such as lack of vitamins and minerals, may contribute to such high incidence. Other factors may also be responsible.Figure 3.: Geographical distribution of patients with head and neck cancer in Saudi Arabia.Download FigureBreast cancer. Population comparison reveals a positive correlation between total fat intake and mortality from mammary cancer.27 Studies of migrants support the view that environmental factors play a significant role in its etiology, for within two generations mortality in migrants approximates that in the host country.28 A growing body of information exists as to plausible reasons for this association. The high fat intake acts as a tumor promoter in rats pretreated with mammary carcinogens, although indirect mechanisms involving endocrine balance do occur.Most of the women with breast cancer in this report were of middle or high economic status, and the majority were from large metropolitan areas. It is possible that acquiring a Western diet, with its high fat content, may play a factor in such distribution.Gynecologic malignancies. Epidemiological data comparable with those pertaining to breast cancer suggest the possibility that Western diet may be responsible for the high incidence of cancer and that modification of such a diet leads to a reduction in the incidence of cancer. In this series, most patients with gynecologic malignancies were of middle or high economic status, and large numbers of these patients were referred from the Eastern Province. Figure 4.Figure 4.: Geographical distribution of patients with gynecologic malignancy in Saudi Arabia.Download FigureIn addition to reducing cancer risks by preventing cigarette smoking and occupational exposure to carcinogens, major emphasis must also be placed on promoting good dietary habits. Improving the quality of potable water, reducing air pollution and avoiding excessive ultraviolet radiation may also be helpful in reducing cancer incidence.Toward an Earlier Detection of CancerEarly diagnosis of cancer is the hallmark of any successful cancer campaign, and it is the first step toward cancer control and ultimately, cancer prevention. Unfortunately, most patients with cancer in Saudi Arabia present themselves to their physicians late in their disease, after a mean interval of 9.4 months. At the time of initial diagnosis, 71 percent of all patients were found to have far advanced Stage III or IV disease. In most instances, the patients’ conditions were beyond any therapeutic cure, and many patients were sent home for terminal care, receiving no treatment except supportive therapy. Early detection of these patients may lead to a longer survival of patients treated, and possibly a cure. In this study, several factors were found to be partly responsible for such delay. Their correction should be the first priority in planning a comprehensive cancer campaign.Age, Sex, and Social StatusThe elderly and women usually consult physicians later than younger patients and men. It may be helpful to give some attention to these groups.Poor patients usually present theselves when the disease is far advanced. Patients of low economic status usually present after a mean interval of 10.3 months. On examination, 76 percent were found to have far advanced Stage III or IV disease. In comparison, patients in a middle or high economic class usually see their physicians earlier, within 8.6 months (p<0.02) and 67 percent of them had Stage III or IV disease (p 0.05). On examination, 34 percent of patients referred from the Eastern Province had an early Stage I or II disease compared to 24 percent of patients from Southern Province (p> 0.05). These data may indicate that special attention should be directed to the Southern Province to detect cancer patients earlier. With the establishment of the new medical school in Abha, and the expansion of hospital facilities in this region, hopefully such a goal will be achieved.Type of malignancy. Patients with esophageal cancer and non-Hodgkin's lymphoma usually present early, and the majority of patients were found to have Stage I or II disease compared with patients with gastrointestinal or lung cancer (p< 0.05). Such differences were mainly attributed to the particular characteristics of each tumor site as well as the extent and rapidity of tumor growth. An inability to swallow due to esophageal obstruction or a rapidly growing tumor mass secondary to malignant lymphoma usually encouraged the patient to seek medical advice earlier, compared with patients with mild and chronic abdominal pain, possibly due to slowly growing gastrointestinal or gynecologic malignancies.Despite all these factors, there was definite improvement in cancer detection in Saudi Arabia in just over the last five years. The mean interval between initial symptoms and clinical diagnosis dropped from 13.1 months during 1977 to 7.5 months during 1981 (p <0.01). Patients with early and possibly curable cancer accounted for 15 percent of patients seen during 1978 compared to 45 percent of patients treated during 1981 (p<0.01). Such improvement is mainly attributed to the great economic development in Saudi Arabia and, particularly, to the vast expansion in health care facilities both in the public and private sectors (Table 3).14 If these trends continue, it is possible that the patterns of cancer in Saudi Arabia will approach those in the Western countries.Table 3. Number of hospitals, hospital beds and physicians in Saudi ArabiaTable 3. Number of hospitals, hospital beds and physicians in Saudi ArabiaARTICLE REFERENCES:1. Stirling G, Khalil AM, Nada GN, et al.: "Malignant neoplasms in Saudi Arabia" . Cancer 44(4): 15431979. Google Scholar2. Klein G: "The Epstein-Barr virus and neoplasia" . 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Google Scholar Previous article Next article FiguresReferencesRelatedDetailsCited byAl Tamimi T, Al-Bar A, Al-Suhaimi S, Ibrahim E, Ibrahim A, Wosornu L and Gabriel G (2019) Lung Cancer in the Eastern Region of Saudi Arabia: A Population-Based Study, Annals of Saudi Medicine , 16:1, (3-11), Online publication date: 1-Jan-1996.Shetty S, Ibrahim A, Patil K, Anandan N, Al-Kotob S and Memon S (2019) Urological Cancers in Asir Region, Annals of Saudi Medicine , 13:2, (207-208), Online publication date: 1-Mar-1993.Beecham J, Alibutud M and Burke M (2019) Fine-Needle Aspiration Biopsy for the Routine Screening of Saudi Patients with Thyroid Nodules, Annals of Saudi Medicine , 8:4, (252-256), Online publication date: 1-Jul-1988. Volume 2, Issue 4October 1982 Metrics History Published online1 October 1982 InformationCopyright © 1982, Annals of Saudi MedicinePDF download
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