Int. J . Cancer: 46, 228-232 (1990) 0 1990 Wiley-Liss, Inc.
Publication of the International Union Against Cancer Publication de I'llnion Internationale Contre le Cancer
CANCER INCIDENCE IN MIGRANTS TO NEW SOUTH WALES Margaret MCCREDIE', Marylon S. COATES and Joyce M. FORD NSW Central Cancer Registry, NSW Cancer Council, North Ryde, New South Wales, Australia. Cancer incidence in migrants to New South Wales (NSW) from the British Isles, north-central, eastern and southern Europe, the Middle East and Asia has been compared with that in Australian-born residents using data from the NSW Central Cancer Registry for 1972-84. Indirectly standardized incidence ratios (SIRS) were low in migrants from all 6 regions for melanoma of skin and cancers of lip and, except in men from eastern Europe, colon. Oesophageal, rectal and prostatic cancers also tended to be relatively less common. Cancers which were more common than in the Australian-born were those of the stomach and, for men, bladder (except in the Asian-born). Migrants from different regions showed variations from the cancer pattern of the Australian-born population which, for the most part, were predictable from the known incidence of cancer in the countries within the region of origin. Exceptions were the high relative incidence of nasopharyngeal cancer in migrants from southern Europe and bladder cancer in men from all regions other than Asia.
birth, relative to that in the Australian-born, is published elsewhere (McCredie and Coates, 1989; McCredie et al., 199Oa,b). METHODS
The population-based NSW Central Cancer Registry receives statutory notifications from hospitals and radiotherapy departments as well as pathology reports and death certificates for all cases of invasive cancer which occur in NSW (McCredie et al., 1988). A total of 183,232 new cases were diagnosed during the period 1972-84. The following analyses were carried out on 177,167 cases (97% of the total) for whom country of birth was known. As computerized data regarding duration of residence in Australia are available for only 10% of the cases, this factor could not be included in the analysis. Geographical regions were delineated prior to examination of the data on the basis of (1) historical, ethnic, cultural and Cancer patterns in migrant populations differ from those of economic grounds, (2) the time and pattern of migration to the host country according to 3 main variables: ethnic group, Australia and (3) patterns of cancer incidence as published cancer site and time since migration (Haenszel, 1982). Studies from individual countries. Regions were included in this study in countries such as the USA and Israel, to which large num- if at least 1,000 new cases of cancer had been diagnosed in bers of people migrated, have demonstrated site-specific can- their migrants during the period 1972-84. Countries were excer profiles in different ethnic groups, the rates of many con- cluded if the age structure of their migrant population was not verging in time towards those of the host country (Locke and available from the Australian Bureau of Statistics. The 6 regions examined were the British Isles, north-central, eastern King, 1980; Haenszel, 1982). Australia also has been the destination of migrants from and southern Europe, the Middle East and Asia; the individual diverse populations seeking refuge from war, persecution or countries which comprise these regions are listed in Table I. Age-standardized incidence ratios were calculated by the poverty. Before the Second World War the majority of migrants came from the British Isles but during 1947-51 there indirect method using, as reference, rates for Australian-born was a substantial increase in the proportion of settlers from residents of NSW (1972-84). Populations at the mid-point of eastern Europe (particularly Poland, Ukraine and the Baltic the period, stratified by sex, 5-year age group and country of states), the Netherlands and Italy. During the 1950s the pro- birth were interpolated linearly from unpublished data from the portion from the last 2 countries increased further, accompa- 1976 and 1981 censuses obtained from the Australian Bureau nied by large numbers from Greece and Germany. The pro- of Statistics. Confidence limits were calculated assuming that portion from southern Europe (Italy, Greece and Yugoslavia) the observed cases followed a Poisson distribution and the level remained high throughout the 1960s and immigration from of significance (a)was set at 0.01 so that 99% confidence Yugoslavia continued at relatively high levels into the earIy intervals which included 100 were not considered statistically 1970s. Since then migration from Asia and the Middle East significant. This level was chosen as being more stringent than (particularly Vietnam and the Lebanon) and New Zealand has the usual 95% but, because of the many comparisons that we increased substantially while there has been a decline in settlers have made, those SIRS that only just reached significance coming from Europe (Australian Bureau of Statistics, 1989). should be interpreted with caution. Average annual cancer incidence rates, directly age-stanCancer mortality in migrants to Australia has been reported in some detail for various countries and regions of birth (Mc- dardized to the "world" population (Doll, 1976), were calcuCall and Stenhouse, 1971; Staszewski et al., 1971; McMichael lated for the migrant groups so that comparisons could be et al., 1980; Armstrong et al., 1983; Zhang et al., 1984; made, where possible, with published incidence rates for their Young, 1986; McMichael and Giles, 1988) but descriptions of countries of origin and for NSW (Waterhouse et al., 1982; patterns of cancer incidence have been restricted to migrants Muir et al., 1987). from the British Isles and southern Europe living in the state of South Australia (McMichael and Bonett, 1981; McMichael and RESULTS Giles, 1988; McMichael et al., 1989) or the city of Melbourne The relative contributions of the migrant groups to the pop(Kune et al., 1986). ulation and the cancer burden of NSW for the period 1972-84 New South Wales (NSW) is in a favourable position for examination of the profiles of cancer incidence in migrant groups as, of all the states in Australia, it has the largest population, of whom one fifth are migrants, and a population'To whom reprint requests should be sent, at the NSW Central Cancer based cancer registry in operation since 1972. This study de- Registry, NSW Cancer Council, PO Box 380, North Ryde, NSW 2113, scribes cancer incidence during the period 1972-84 in migrants Australia. to NSW from 6 geographical regions: the British Isles, northcentral, eastern and southern Europe, the Middle East and Received: March 26, 1990. Asia. The incidence in migrants from individual countries of
CANCER INCIDENCE IN MIGRANTS TO NEW SOUTH WALES
229
TABLE I - ESTIMATES OF POPULATIONS IN NEW SOUTH WALES AT THE MID-POINT OF 1972-84, AND TOTAL CANCER REGISTRATIONS DURING 1972-84 BY REGION OF BIRTH Region of birth
British Isles' Europe-north-central2 -eastern3 -southern4 Middle East5 Asia6 Australia Total
Number of persons
% aged 65 years or more
338,864 (6.9%) 85,645 (1.7%) 57,377 (1.2%) 231,650 (4.7%) 63,934 (1.3%) 75,243 (1.5%) 3,942,079 (80.2%) 4,916,926 (100%)
19.1 7.9 19.8 6.0 4.6 5.1 9.1
Number of cancers
20,377 (11.5%) 3,392 (1.9%) 4,458 (2.5%) 6,504 (3.7%) 1,357 (0.8%) 1,766 (1.O%) 135,692 (76.6%) 177,167 (100%)
'England, Wales. Scotland. Ireland (including Eue).-'Auswia, Belgium, Denmark, Finland, France Germany, Netherlands Norway, Sweden, S~itzerland.-~Bulgaria, Czechoslovakia, Estonia, Hungiuy, Latvia, Lithuania, Poiand, Romania, Ukraine: USSR.-4Cyp~s, Greece, Italy, Malta, Portugal, Spain. Yugo~lavia.-~Egypt,Iran, Iraq, Israel, Lebanon, Syria, Turkey. -61nduding Burma, China, Hong Kong, Indonesia, India, Japan, Malaysia, Pakistan, Philippines, Singapore, Sri Lanka, Thailand, Vietnam.
are given in the first and third columns of Table I. The different age structures of the populations, expressed in terms of the percentages from each region who were aged over 65 years, given in the second column, underlie the necessity for agestandardization. The age-standardized incidence ratios (SIRs) in Tables II and 1II show that, in migrants from southern Europe and the Middle East, and in men from eastern Europe and Asia, cancer at all sites was less common than in the Australian-born while being more common in women born in eastern Europe (bordering on significance). In migrants from all regions, melanoma of skin and cancer of the lip were less frequent than in native-born Australians. Colon cancer also was relatively less common (except for men born in eastern Europe) and, while this was true generally for rectal, oesophageal and prostatic cancers, many of the SIRs did not reach significance. By contrast, the relative incidence of stomach cancer tended to be high in migrants and bladder
cancer was more common in men from all regions (except Asia) than in the native-born Australians. The SIRs for lung cancer were high in migrants from the British Isles, men from north-central Europe and women from Asia but low in migrants from southern Europe and the Middle East, and in men from eastern Europe and Asia. This difference between Asian men and women was emphasized when the analysis was restricted to adenocarcinoma of the lung (for women: SIR = 264, 99% confidence interval, 149-427; for men (105; 99% confidence interval, 61-168). Breast cancer was relatively less common in women from southern Europe while being more frequent in women from the British Isles. SIRs tended to be low for cancers of the cervix and ovary in women from southern Europe and the Middle East and high in those from north-central and eastern Europe, British Isles (ovary only) and Asia (cervix only); not all SIRs reached significance. The SIRs for testicular cancer were low in men from south-
TABLE II - AGE-STANDARDIZEDINCIDENCE RATIOS' (AND 99%CONFIDENCE INTERVALS) FOR CANCER IN MALE MIGRANTS TO NEW SOUTH WALES, DURING 1972-84, BY REGION OF BIRTH AND SITE Site (ICD-9)2 ~~
North-central
Europe Eastern
Southem
34 (2546) 82 (66-100) 95 (47-170) 54 (39-73) 92 (75-112) 131 (119-144) 87 (80-95) 96 (87-107) 96 (61-142) 96 (69-129) 104 (91-119) 86 (71-103) 128 (122-135)
22 (7748) 57 (30-96) 102 (17-323) 64 (31-116) 69 (36-119) 128 (98-163) 68 (53-86) 86 (65-11 1) 117 (37-274) 85 (31-181) 123 (87-168) 98 (64-145) 128 (114-144)
38 (19-66) 58 (35-90) 104 (22-295) 63 (35-104) 64 (38-101) 178 (149-210) 100 (85-117) 103 (84-126) 197 (103-336) 66 (27-133) 115 (87-150) 76 (51-109) 88 (78-98)
24 (13-39) 42 (27-62) 319 (193489) 59 (38-88) 49 (30-74) 164 (142-189) 56 (47-66) 76 (63-91) 245 (156-362) 136 (86-202) 110 (87-136) 89 (67-115) 91 (83-100)
342 (100-858) 25 (3-91) 30 (5-83) 108 (69-162) 46 (29-69) 70 (43-107) 485 (222-909) 210 (83438) 99 (54-165) 78 (36-147) 72 (56-91)
135 (83-208) 108 (79-144) 37 (31-43) 88 (82-93) 117 (91-148) 200 (128-297) 128 (118-140) 85 (71-100) 104 (85-125) 92 (55-142) 87 (76-100) 101 (8Ck126) 95 (82-110) 99 (96101)
73 (12-229) 92 (41-177) 39 (28-53) 86 (70-104) 115 (72-175) 90 (10-333) 169 (138-205) 92 (61-134) 129 (88-182) 71 (18-186) 89 (65-1 19) 118 (65-195) 89 (60-127) 96 (91-102)
68 (8-249) 153 (84-253) 28 (1840) 68 (57-80) 134 (68-235) 162 (52-380) 132 (110-157) 118 (88-155) 103 (68-148) 197 (94-386) 94 (71-121) 90 (53-143) 118 (88-155) 93 (89-98)
80 (33-160) 107 (70-157) 17 (12-22) 64 (55-74) 34 (20-54) 203 (98-367) 128 (110-147) 90 (68-114) 101 (78-129) 111 (62-181) 72 (58-88) 116 (80-162) 103 (82-128) 79 (76-83)
94 (9-293) 147 (62-287) 18 (9-32) 76 (54-104) 44 (16-93) 198 (22-732) 171 (126-227) 82 (42-145) 81 (41-143) 301 (137-564) 113 (77-160) 101 (35-225) 142 (92-209) 79 (71-86)
British Isles
Middle East
Asia
~
Lip (140) Mouth (141,143-5) Nasopharynx (147) Pharynx (146,148,149) Oesophagus (150) Stomach (151) Colon (153) Rectum (154) Liver (155) Gall-bladder (156) Pancreas (157) Larynx (161) Trachea, bronchus and lung (162)
Bone (170) Connective tissue (171) Melanoma of skin (172) Prostate (185) Testis (186) Other genital (187) Bladder (188) Kidney and ureter (189) Brain (191) Thyroid (193) Lymphomas (200-202) Multiple myeloma (203) Leukaemias (204-208) All cancers (140-208)
'Standardized incidence ratio for the Australian-born
=
33 (9-80)
40 (11-98)
100.-2Ninth revision of the International Classification of Diseases.
4 (0-32) 50 (19-108) 2204 (1492-3186) 61 (19-141) 106 (50-195) 157 (112-215) 62 (43-87) 68 (43-102) 1087 (688-1616) 185 (73-386) 102 (58-164) 33 (9-80) 81 (65-99) 105 (22-295) 52 (11-148) 10 (4-21) 78 (57-103) 49 (20-98) 117 (6-545) 71 (45-107) 85 (46-144) 93 (51-155) 131 (38-324) 81 (52-119) 117 (48-237) 102 (63-156) 83 (75-90)
230
MCCREDIE ET AL.
TABLE Ul - APE-STANDARDIZED INCIDENCE RATIOS’ (AND 99% CONFIDENCE INTERVALS) FOR CANCER IN FEMALE MIGRANTS TO NEW SOUTH WALES, DURING 1972-84, BY REGION OF BIRTH AND SITE Site (1CD-9)*
Lip (140) Mouth ( 141.143-5) Nasophkynx (147) Pharynx (146,148,149) Oesophagus (150) Stomach (151) Colon (153) Rectum (154) Liver (155) Gall-bladder (156) Pancreas (157) Larynx (161) Trachea, bronchus and lung (162) Bone (170) Connective tissue (171) Melanoma of skin (172) Breast (174) Cervix uteri (180) Body of uterus (182) Ovary (183) Other genital (184) Bladder (188) Kidney and ureter (189) Brain (191) Thyroid (193) Lymphomas (200-202) Multiple myeloma (203) Leukaemias (204-208) All cancers (140-208)
North-central
Europe Eastern
Southern
24 (9-52) 93 (68-123) 59 (10-185) 111 (67-171) 119 (94-148) 127 (112-143) 89 (81-96) 93 (82-105) 108 (49-203) 74 (54-97) 97 (82-1 14) 147 (88-230) 164 (14%181)
0 (0-81) 63 (22-140) 0( M I ) 132 (38-323) 40 (1G-105) 174 (125-235) 64 (48-82) 92 (65-126) 207 (45-590) 100 (44-192) 122 (77-182) 54 (3-251) 114 (84-149)
0 (0-691 72 (31-141) 320 (56-1050) 72 (16-205) 57 (2>116) 196 (152-249) 76 (61-93) 93 (69-123) 36 (0-275) 189 (119-286) 133 (93-184) 130 (33-340) 119 (92-151)
79 (35-151) 79 (5&119) 41 (3549) 109 ( 103-1 15) 101 (88-115) 90 (78-103) 117 (103-133) 138 (107-176) 116 (99-136) 74 (59-92) 108 (85-135) 76 (55-103) 91 (78-105) 87 (65-1 13) 94 (78-112) 99 (96-101)
221 (71-517) 140 (60-274) 35 (24-50) 102 (89-1 15) 134 (105-167) 115 (85-152) 160 (123-203) 158 (75-292) 91 (55-143) 127 (80-189) 79 (41-137) 83 (41-147) 75 (49-108) 103 (47-193) 70 (38-117) 98 (91-104)
176 (38-505) 232 (120403) 39 (25-57) 97 (86110) 143 (111-182) 128 (99-163) 150 (116190) 59 (19-138) 116 (79-164) 97 (61-146) 112 (65-180) 200 (121-310) 97 (69-133) 126 (70-206j 122 (81-177) 107 (100-113)
British Isles
Middle East
Asia
28 (5-87) 65 (33-1 14) 340 (115-742) 47 (10-134) 14 (244) 194 (157-237) 52 (42-631 69 (53-89j 55 (6-203) 158 (103-231) 116 (84-156) 66 (14-186) 53 (39-71)
0 (0-166) 32 (2-149) 302 (15-1325) 42 (0-310) 0 (0-81) 148 (85-239) 55 (35-82) 73 ( a . 1 2 3 ) 258 (28-915) 209 (90-412) 106 (48-198) 240 (39-741) 82 (47-132)
0 (0-126) 36 (4-133) 2963 ( 1747-5 127) 97 (11-354)
76 (22-186) 106 (59-176) 18 (13-24)’ 84 (77-92) 86 (72-103) 84 (66-105) 81 (63-101) 100 (53-172) 85 (59-118) 60 (38-90) 109 (77-150) 138 (101-184) 79 (61-101) 112 (68-173) 95 (68-128) 77 (73-81)
186 (39-525) 207 (81-430) 10 &22) -‘ 93 (76-112) 78 (50-ii6j 110 (68-168) 53 (2696) 106 (22-302) 79 (33-160) 15 (1-67) 150 (79-257) 150 (78-261) 131 (84-193) 138 (48-308) 120 (64402) 84 (76-93)
60 (41-84) 68 (40-109) 455 (134-1144) 194 (91-355) 111 (58-190) 45 (0-338) 178 (130-237) ’
154 (32430) 91 (76-107) 138 (104-180) 101 (65-148) 102 (6615ij 32 (2-150) 75 (34-14b) 65 (27-132) 33 (8-86) 126 (67-217) 82 (50-126) 127 (50-126) 103 (58-169) 93 (861021
‘Standardized incidence ratio for the Australian-born = 100.-*Ninth revision of the International Classification of Diseases.
em Europe, the Middle East and Asia. “Other genital” cancers were more common in men and women from the British Isles than in the Australian-born. Liver cancer was more frequent in migrants from Asia and in men from southern and eastern Europe and the Middle East, while the relative incidence of cancer of the gall-bladder and extrahepatic bile ducts was high in women from these regions but low in British women. Although cancers of the mouth and, in men only, pharynx tended to be less frequent than in the Australian-born, nasopharyngeal cancer was more common in migrants from southern Europe and Asia while the high SIR for men from the Middle East bordered on significance. Other significant findings were low SIRs for kidney cancer in women from the British Isles, southern Europe and the Middle East, for laryngeal cancer in men from Asia, for brain cancer in women from Asia and for lymphomas in men from southern Europe; high SIRs were found for thyroid cancer in women from southern and eastern Europe for men from the Middle East and for cancer of connective and other soft tissue in women from eastern Europe. DISCUSSION
There were only 2 cancers for which migrants generally had higher rates than the Australian-born. These were stomach cancer (not reaching significance in either sex in the Middle East) and, in men only, bladder cancer (except Asia). High relative rates for stomach cancer have been a consistent finding in early studies of migrants not only in Australia (Staszewski et al., 1971; Armstrong et al., 1983; McMichael et al., 1980, 1989) but also in the United States (Haenszel, 1982; Thomas and Karagas, 1987). They can be explained by higher rates in the countries of birth (Waterhouse et al., 1982; Muir et al., 1987) as environmental exposures early in life are thought to be cnt-
ical (Haenszel, 1982). Of the countries in the Middle East included in Cancer Incidence in Five Continents (Muir et al., 1987), Kuwait showed low stomach cancer rates, but in the various populations of Israel rates were generally higher than in NSW. The high ratios for bladder cancer in men from the 5 regions are a new finding, previously seen in Australian data only in men born in England and Czechoslovakia (mortality; Armstrong et al., 1983) and the United Kingdom and Ireland (incidence; McMichael et al., 1989). Standardized (world) incidence rates, calculated for bladder cancer from the data used in the present study, ranged from 19.5 to 25.5 per 1OO,OOO, and were clearly higher than published rates for the majority of countries from which these migrants came (Waterhouse et al., 1982; Muir et al., 1987). This fact, coupled with an absence of high rates in migrant women (except in those from the British Isles), indicates that an exposure occurring after arrival in Australia might be responsible. Tobacco smoking is unlikely to be responsible as there was no parallel increase in lung cancer. As many of the migrants to NSW settled either in Sydney, the largest city in Australia, or in 2 provincial cities, Newcastle and Wollongong, which are centres of heavy industry, it is possible that occupational exposure to hazardous chemicals is the explanation for the increased risk. The excess of bladder cancer was not seen in men from Asia or New Zealand (McCredie et al., 1990a), 2 migrant groups who, on the whole, entered Australia more recently. Nor was it apparent in the mortality data from 1962-71 (Armstrong et al., 1983). Both of these observations are consistent with the hypothesis that it is exposure since coming to Australia that is responsible for the excess of bladder cancer in migrants. The low incidence of cancers of the colon and lip and melanoma of skin in migrants from all regions, in relation to the Australian-born, accords with previous findings (Armstrong et al., 1983; Kune et al., 1986; McMichael et al., 1980, 1989).
23 1
CANCER INCIDENCE IN MIGRANTS TO NEW SOUTH WALES
This can be explained on the basis of lower rates in the countries of birth (Waterhouse et al., 1982; Muir et al., 1987) and for the last 2 cancers, a lower exposure to sunlight at an early age (Holman e f al., 1986) and by a darker skin colour in the case of migrants from southern Europe, the Middle East and Asia. Dietary differences between other countries and Australia and the changes made by migrants towards the more “affluent” eating habits prevalent here, described comprehensively by McMichael (1985) and McMichael et al. (1979, 1980, 1989) McMichael and Bonett (1981) and McMichael and Giles (1988), may be sufficient to explain the lower relative rates of colon, prostate and, for some regions, breast cancers. Several other cancers tended, in general, to have lower rates in migrants than in native-born Australians although not all SIRs reached significance. These included cancers of mouth, pharynx (excluding nasopharynx), oesophagus, rectum and kidney, and lymphomas. For the most part these cancers are less common in the migrants’ country of birth than in Australia, exceptions being the kidney in north-central and eastern Europe (Muir et al., 1987) and pharynx and oesophagus in northern France, Belgium and parts of central Asia (Day, 1984). Rates for all the cancers listed above tended to be intermediate between those prevailing in NSW and the region of origin (Muir et al., 1987). The high incidence of lung cancer in Asian women (SIR = 178), despite the low rates in Asian men (81), relative to native-born Australians, was not exclusively due to rates in women born in China (SIR = 220; 99% confidence limits 137-333; McCredie and Coates, 1989) who made up only 16.5%of the female Asian-born population. Although we have no data on ethnicity, many of the Asian migrants from Hong Kong, Indonesia, Malaysia, Singapore and Vietnam also would be ethnic Chinese, the majority of them from families originating in southern China. In China the male:female ratio for lung cancer is the lowest in the world (Jun-Yao, 1989). Case-control studies of Chinese in Hong Kong (Chan et al., 1979) and Singapore (MacLennan et al., 1977) have found a substantial proportion of female cases to be non-smokers and, in Singapore, adenocarcinoma of the lung occurs more commonly among Cantonese women than men (Law et al., 1976). While we do not know the prevalence of smoking among our migrants, adenocarcinoma of the lung was similar in frequency between Asian-born women and men (world standardized incidence: 6.2 and 7.3 per 100,000 respectively) and more frequently among women (15.2) than men (10.9) in migrants from China alone, while the reverse was true of the Australianborn (women: 2.2; men: 7.0). This resulted in SIRs for adenocarcinoma of the lung that were significantly high among women born in Asia (264) or in China when considered alone (457) but not among men (105 and 102 respectively). The elevated relative rates of nasopharyngeal cancer among migrants from Asia and southern Europe and men from the Middle East in this and previous studies (Asia: Armstrong et al., 1983; Zhang et al., 1984; southern Europe including Malta: McMichael et al., 1989) reflect the high incidence of this cancer among people of Chinese origin and from areas of northern Africa as well as Malta (Waterhouse et al., 1982; Muir et al., 1987). However, Maltese migrants (SIR = 847 in men; no cases in women) were not the sole contributors to the high ratios in southern European migrants living in NSW as men from Greece (378), and Italian-born men (324) and
women (480) also had significantly increased rates (McCredie et al., 19906). In general, patterns of cancer incidence for migrants from southern Europe and the Middle East were similar, although rates for stomach cancer in those born in the Middle East tended to be lower. These were the only 2 regions to have low SIRs for lung cancer in both men and women. Migrants from these 2 areas resembled the Asian-born in having high rates for cancers of the nasopharynx, liver (men), gall-bladder and thyroid (women; also in eastern European migrants) and low rates for testicular cancer. In migrants from the 3 remaining regions, the general pattern of cancer incidence was similar. However, women from northcentral Europe resembled more closely the women from eastern Europe with high rates for cancers of the lung, uterus and ovary, than those from the British Isles who had high rates for lung, breast and ovary. A seemingly isolated finding in eastern European women was the high SIR (232) for connective and other soft tissue but a high ratio (304) also has been noted in male Russian and Ukrainian migrants (McCredie et al., 1990b). In the case of men, those born in the British Isles and north-central Europe had high relative rates for lung cancer whereas those born in eastern Europe had low rates, the difference between the 2 groups being significant. The British-born alone had a significantly high SIRs for “other genital” cancers (in men, predominantly penile, SIR = 200; in women, vulva and vagina, SIR = 138). The occurrence of high rates of “other genital” cancers in British migrants of both sexes provides evidence in favour of the previously suggested link between external genital cancers in men and women (Peters et al., 1984). This may be related to the prevalence of circumcision, lower in the British Isles (Editorial. 1979) than in Australia (Wirth, 1982). For the most part, the relative incidence patterns can be explained by the incidence in the countries of birth but migrants are self-selected and cannot be regarded as representative of the population in their homelands. Changing incidences in either the country of origin or in Australia may distort the relationships and should be considered when making deductions about site-specific data from an individual country or region. In addition, it must be remembered that most migrants from north-central and eastern Europe, south-east Asia and Lebanon were refugees from war or political, racial or religious persecution while the majority of those from southern Europe, other parts of the Middle East and Asia differ in being economic refugees. While the site-specific cancer rates generally were intermediate between rates in NSW and those prevailing in the region of birth, bladder cancer has been identified in this study as having higher rates in the migrant groups (other than Asian). It is suggested that this is due to occupational exposure experienced by male migrants, who, on arrival in NSW, obtained initial employment in heavy industry whatever their previous occupations had been. The high relative rates of 2 uncommon cancers in migrants from particular regions, namely, nasopharyngeal cancer in southern Europeans (McCredie et al., 1990b) and connective and other soft-tissue cancers in eastern Europeans (McCredie et al., 1990b), leads one to suspect that these cancers have been more common in their respective home countries than has hitherto been recognized.
REFERENCES ARMSTRONG, B . K . , WOODINGS, T.L., STENHOUSE, N.S. and MCCALL, M.G.. Mortality from cancer in miarants to Australia. 1962-1971. NH and MRC Rese&h Unit in EpidemiGlogy and Preventive Medicine, University of Western Australia, Perth (1983). AUSTRALIAN BUREAUOF STATISTICS, Overseas born Australians 1988: a statistical profile, 41 12.0, ABS, C&berra (1989).
CHAN,W.C., COLBOURNE, M.J., FUNG,S.C. and Ho, H.C., Bronchial cancer in Hone Kone 19761977. Brit. J . Cancer, 39. 182-192 f1979). , ,
-
-
N.E., The geographicalpathologyof cancer of med. Bull., 40, 329-334 (1984).
DAY,
the
oesophagus, Brit.
DOLL,R., Comparison between registries. Age-standardized rates. In: J.
232
MCCREDIE ET AL.
Waterhouse, C. Muir, P. Correa and J. Powell (eds.), Cancer incidence in five continents. Vol. 111, IARC Scientific Publication 15, IARC, Lyon (1976). EDITORIAL, The case against neonatal circumcision.Brit. J. Med., 1, 1163 (1979). HAENSZEL, B., Migrant studies. In: D. Schottenfeld and J.F. Fraumeni (eds.), Cancer epidemiology and prevention. Saunders, Philadelphia ( 1982). HOLMAN,C.D., ARMSTRONG, B.K., HEENAN, P.J., BLACKWELL, J.B., CUMMINC, F.J., ENGLISH,D.R., HOLLAND, S., KELSALL,G.R.H., MATZ,L.R., ROUSE,I.L., SINGH,A., TENSELDAM, R.E.J., WATT,J.D. and Xu, Z., The causes of malignant melanoma: results from the Western Australian Lions melanoma research project. In: R.P. Gallagher (ed.), Epidemiology of malignant melanoma, pp. 18-37, Springer, Berlin (1986). JUN-YAO, L., Cancer mapping as an epidemiologic resource in China. In: P. Boyle, C.S. Muir and E. Grundmann (eds.), Recent Results in Cancer Research. Vol. 114, Cancer mapping, pp. 115-136, Springer, Heidelberg (1989). KUNE,S., KUNE,G. and WATSON, L., The Melbourne colorectal cancer study: incidence findings by age, sex, migrants and religion. Int. J. Epidemiol., 15, 483493 (1986). LAW,C.H., DAY,N.E. and SHANMUGARATNAM, K., Incidence rates of specific histological types of lung cancer in Singapore Chinese dialect groups and their aetiological significance. Int. J. Cancer, 17, 304-309 (1976). LOCKE,F.B. and KING, H., Cancer mortality risk among Japanese in the United States. J. nut. Cancer Inst., 65, 1149-1156 (1980). MACLENNAN, R., DA COSTA,J., DAY,N.E., LAW,C.H., NG, Y.K. and SHANMUGARATNAM, K., Risk factors for lung cancer in Singapore Chinese, a population with high female incidence rates. Int. J. Cancer, 20, 854-860 (1977). MCCALL,M.G. and STENHOUSE, N.S., Deaths from lung cancer in Australia. Med. J. Austr., 1, 524-525 (1971). MCCREDIE,M. and COATES,M.S., Cancer incidence in migrants to New South Wales, 1972 to 1984. NSW Cancer Council, Sydney (1989). MCCREDIE,M., COATES,M.S. and FORD,J.M., The changing incidence of cancers in adults in New South Wales. Int. J . Cancer, 42, 667-671 (1988). MCCREDIE, M., COATES, M.S. and FORD,J.M., Cancer incidence in New Zealand-born residents of New South Wales. N . Z . med. J . , 103, 61-63 (1990~).
MCCREDIE,M., COATES,M.S. and FORD, J.M., Cancer incidence in European migrants to New South Wales. Ann. Oncol., 19906. (In press). MCMICHAEL, A.J., Diet, nutrition and disease. Med. J. Austr., 142, 121124 (1985). MCMICHAEL, A.J. and BONETT,A., Cancer profiles of British and southern-European migrants. Exploring South Australia's Cancer Registry data. Med. J . Austr., 1, 229-232 (1981). MCMICHAEL, A.J., BONETT,A. and RODER,D., Cancer incidence among migrant populations in South Australia. Med. J. Austr., 150, 417420 (1989). MCMICHAEL, A.J. and GILES,G.G., Cancer in migrants to Australia: extending the descriptive epidemiological data. Cancer Res., 48,75 1-756 (1988). MCMICHAEL, A.J., MCCALL,M.G., HARTSHORNE, J.M. and WOODINGS, T.L., Patterns of gastro-intestinalcancer in European migrants to Australia: the role of dietary change. Int. J. Cancer, 25, 431-437 (1980). MCMICHAEL, A. J., POTTER,J.D. and HETZEL,B.S., Time trends in colorectal cancer mortality in relation to food and alcohol consumption:United States, United Kingdom, Australia and New Zealand. Int. J. Epidemiol., 8, 295-303 (1979). MUIR,C., WATERHOUSE, J., MACK,T., POWELL,J. and WHELAN,S., Cancer incidence in five continents, VoL V, IARC Scientific Publication 88, IARC, Lyon (1987). PETERS,R.K., MACK,T.M. and BERNSTEIN, L., Parallels in the epidemiology of selected anogenital carcinomas. J. nut. Cancer Znsr., 72,609615 (1984). STASZEWSKI.J.. MCCALL.M.G.. HAKTSHORNE. J.M. and WOODINGS. T.L., Cancer mortality in '1962-66 among Polish migrants to Australia: Brit. J . Cancer, 25, 599-610 (1971). THOMAS, D.B. and KARAGAS, M.R., Cancer in Fist and second generation Americans. Cancer Res., 47, 5771-5776 (1987). WATERHOUSE, J., MUIR, C., SHANMUCARATNAM, K. and POWELL,J., Cancer incidence infive conrinents, Vol. IV, IARC Scientific Publication 42, IARC, Lyon (1982). WIRTH,J.L., Current circumcision practices in Australia. Med. J. Austr., 1, 177-179 (1982). YOUNG,C., Selection and survival. Immigrant mortality in Australia. Department of Immigration and Ethnic Affairs, Canberra (1986). ZHANG,Y .O., MACLENNAN, R. and BERRY,G., Mortality of Chinese in New South Wales, 1969-1978. Inr. J. Epidemiol., 13, 188-192 (1984).