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M J S Langman a Department of Medicine University of
Birmingham, Birmingham, B15 2TT, b Department of Public Health and
Epidemiology, University of Birmingham
Correspondence to: M J S Langman m.j.langman{at}bham.ac.uk
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Abstract |
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Objective:
To examine whether anti-inflammatory drug treatment protects against the commoner cancers in the United Kingdom.
Epidemiological evidence has consistently shown that
people who have taken aspirin or other non-steroidal anti-inflammatory drugs are at reduced risk of developing or dying from colon
cancer.
1 2
The extent to which treatment protects against
other cancers is unclear, although in epidemiological studies fewer
fatal cases of gastric and oesophageal cancer than expected have been
found2 and the occurrence of experimentally induced
bladder, breast, and colon cancer in animals has been reduced by giving
non-steroidal anti-inflammatory drugs concurrently with
carcinogens.3-5
The extent to which treatment might protect against different varieties
of cancer in humans could be investigated by separate case-control or
case-cohort studies, but this time consuming and labour intensive
method can be avoided by examining information held on automated
databases that record drug prescriptions and clinical outcomes. We used
the general practice research database to examine information about
previous prescription of aspirin and other non-steroidal
anti-inflammatory drugs and occurrence of the common cancers in the
United Kingdom.
The general practice research database is a national
dataset managed for the Department of Health containing anonymised
patient records on about four million UK residents. Contributing
general practices, which are distributed throughout the United Kingdom, record standard data on demography, morbidity, and prescriptions and
selected other information. The quality of data is regularly assessed.6 With ethics committee approval we identified
practices with at least four years of information meeting the required
standard and abstracted data on all patients with a first diagnosis of five gastrointestinal cancers (oesophagus, stomach, pancreas, colon,
and rectum) and four non-gastrointestinal cancers (bladder, breast,
lung, and prostate) during 1993-5. Each case was then individually
matched for age (within five years), sex, and general practice with
three controls. Controls were patients without a diagnosis of the
case's type of cancer at the time the case was diagnosed. We also
obtained information on recorded current smoking habits.
Data on prescriptions for aspirin and other non-steroidal
anti-inflammatory drugs (all drugs listed in British National
Formulary subsection 10.1.1) were extracted for each case and
control for the 13-36 months before cancer diagnosis (and equivalent
data were extracted for controls). Information on smoking habits was used to classify patients as ever smokers or never smokers. Conditional logistic regression was used to analyse associations between numbers of
prescriptions and risk of cancer for all sites together and each
separately. Odds ratios (adjusted for smoking habits and age) were
calculated with 95% confidence intervals, and dose-response relations
were tested for trend. In the primary analyses we examined overall
cancer incidence in relation to drug use and compared risks of
gastrointestinal and non-gastrointestinal cancers.
We identified 12 174 patients with a first diagnosis of
the study cancers in 1993-5 who had prescription data available for the
previous 36 months. Eighteen patients with multiple cancers were
excluded from analyses of individual sites, with their controls. Table
1 shows, for each cancer site, the numbers of cases and matched
controls by sex and the numbers who had ever received prescriptions for
aspirin or other non-steroidal anti-inflammatory drugs.
Table 1.
Design:
Case-control study using the general practice research database.
Setting:
Practices throughout United Kingdom providing data to the database.
Subjects:
Patients who had a first diagnosis of five gastrointestinal (oesophagus, stomach, colon, rectum, and pancreas) cancers and four non-gastrointestinal (bladder, breast, lung, and
prostate) cancers in 1993-5 for whom prescription data were available
for the at least the previous 36 months. Each case was matched for age,
sex, and general practice with three controls.
Main outcome measure:
Risk of cancer.
Results:
In 12 174 cancer cases and 34 934 controls overall risk of the nine cancers was not significantly reduced among
those who had received at least seven prescriptions in the 13-36 months
before cancer diagnosis (odds ratio 0.98, 95% confidence interval 0.89 to 1.07). Findings were nevertheless compatible with protective effects
from anti-inflammatory drugs against cancers of the oesophagus (0.64, 0.41 to 0.98), stomach (0.51, 0.33 to 0.79), colon (0.76, 0.58 to
1.00), and rectum (0.75, 0.49 to 1.14) with dose related trends. The
risk of pancreatic cancer (1.49, 1.02 to 2.18) and prostatic cancer
(1.33, 1.07 to1.64) was increased among patients who had received at
least seven prescriptions, but the trend was dose related for only
pancreatic cancer.
Conclusions:
Anti-inflammatory drugs may protect
against oesophageal and gastric cancer as well as colon and rectal
cancer. The increased risks of pancreatic and prostatic cancer could be due to chance or to undetected biases and warrant further investigation.
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Introduction
Top
Abstract
Introduction
Methods
Results
Discussion
References
![]()
Methods
Top
Abstract
Introduction
Methods
Results
Discussion
References
![]()
Results
Top
Abstract
Introduction
Methods
Results
Discussion
References
Table 2 shows the odds ratios for gastrointestinal cancer associated with receipt of prescriptions for aspirin or other non-steroidal anti-inflammatory drugs in the periods studied. For oesophageal, gastric, colon, and rectal cancer the odds ratios tended to fall with increasing number of prescriptions issued. The trends occurred in both the 13-24 and 25-36 months before cancer diagnosis and were significant for oesophageal and gastric cancer in the combined period of 13-36 months (P=0.03 and P=0.02 respectively). For patients who had received at least seven prescriptions in the 13-36 months before diagnosis, odds ratios were consistently reduced for oesophageal (0.64, 95% confidence interval 0.41 to 0.98), gastric (0.51, 0.33 to 0.79), colon (0.76, 0.58 to 1.00), and rectal (0.75, 0.49 to 1.14) cancer, with matching, though not always significant, dose related trends.
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By contrast, odds ratios were raised significantly in patients who had
received at least seven prescriptions in the 13-36 months before
diagnosis of pancreatic cancer (1.49, 1.02 to 2.18). Figures for
prostatic cancer were also consistently raised, and the trend was
highly significant (P<0.0001), although without a clear dose-response
relation. Odds ratios for bladder and breast cancer were close to
unity, and there was an insignificant trend towards a reduced risk for
lung cancer. When all the nine cancers were considered together the
odds ratio was close to unity (0.98, 0.89 to 1.07) in patients
receiving at least seven prescriptions in the 13-36 months before
cancer diagnosis. The odds ratios in table 2 were adjusted for age and
smoking, although the estimates without adjusting were similar for all
cancer sites.
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Discussion |
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We found trends towards reduced incidence of colorectal cancers among people taking aspirin or other non-steroidal anti-inflammatory drugs, with the greatest reductions among those receiving more prescriptions. Our findings are similar to those of most previous case-cohort studies 1 2 7-9 but do not show the stronger protection found in some case-control studies. The trends towards protection existed whether drug prescription was examined in the 13-24 months or 25-36 months before cancer diagnosis.
We also found evidence of protection against oesophageal and gastric cancer. Four of the six previous studies were too small to give reliable information.9-12 Thun et al found non-significant evidence of protection in 176 patients dying of oesophageal cancer and 308 dying of gastric cancer,2 and Farrow et al, in a case-control study of over 500 cases each of oesophageal and gastric cancer, noted significant reductions in risk of oesophageal adenocarcinoma and squamous carcinoma (odds ratios 0.37 and 0.49 respectively) and of non-cardia gastric carcinoma (0.46) but not of cardia cancer.13 Our findings support the case for protection and suggest that protection may be at least as good as for colorectal cancer. The results for gastric cancer could have been confounded by avoidance of anti-inflammatory drugs for patients infected with H pylori (a known risk factor for gastric cancer). However, this seems unlikely because similar raised risks were found for oesophageal cancer and because adverse effects of these drugs have not been convincingly shown to be more common in people who are infected.
Non-gastrointestinal cancers
We found little evidence of protective effects of
non-steroidal anti-inflammatory drugs on non-gastrointestinal cancers.
Protection against breast cancer has been suggested by two studies (one
of aspirin9 and one of other
non-steroidals14) but not by other studies that examined
aspirin exclusively
2 15
or predominantly.16
Our study is larger than these and found no evidence of protection
despite the experimental finding that development of mammary tumours is
inhibited by such drugs.4 One study has suggested
protection against lung cancer,9 but this finding was not
supported by two others
15 17
or by our study, which was
larger than the other studies.
Validity of results
Our data may be criticised on the grounds that the drug
prescription periods examined were relatively close to the time of
diagnosis of cancer. However, trends towards protection were at least
as evident for drug prescriptions 25-36 months before cancer diagnosis
as in the 13-24 months beforehand. Secondly, examination of individual
patient records indicated that the same patients were likely to receive
prescriptions in the two periods. This agrees with other evidence
suggesting that people taking anti-inflammatory drugs tend to do so
long term. Furthermore, although it is plausible that such drugs might
be prescribed to people with undiagnosed cancer, it is difficult to
understand why they might be relatively underprescribed in patients
with gut epithelial cancers.
Mechanism of protection
Colon cancer has been intensively studied, and up
regulation of the cyclo-oxygenase 2 (cox-2) gene has been consistently
shown in 80% or more of cancers.
20 21
Up regulation of
cox-2 expression has been shown in tumours of the oesophagus, stomach,
and breast,22-24 but evidence of protection against
breast cancer is insecure. The assumption that cox-2 inhibition is the critical mechanism may not be justified, although gastrointestinal effects could reflect responses to high levels of direct drug exposure.
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What is already known on this topic
Treatment with aspirin and other non-steroidal anti-inflammatory drugs is associated with protection against colorectal cancer Evidence of protection against other cancers is uncertain What this study addsIn the 13 to 36 months before cancer diagnosis, treatment with non-steroidal anti-inflammatory drugs seemed to lower the risk of oesophageal, gastric, colon, and rectal cancer No effect was found on bladder, breast, or lung cancer Risk of pancreatic and prostatic cancer was increased, although this was not necessarily a causal relation |
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Acknowledgments |
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Contributors: MJSL and KKC designed the study and wrote the paper. GAG and RJL processed and analysed the data. The study guarantor is MJSL.
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Footnotes |
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Funding: Medical Research Council.
Competing interests: MJSL has been a consultant to Merck Sharp and Dohme.
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References |
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| 1. |
Giovannucci E, Rimm EG, Stampfer MJ, Colditz GA, Ascherio A, Willett WC.
Aspirin use and the risk of colorectal cancer and adenoma in male health professionals.
Ann Intern Med
1994;
121:
241-246 |
| 2. |
Thun MJ, Namboodiri MM, Calle EE, Flanders DW, Heath Jr CW.
Aspirin use and risk of fatal cancer.
Cancer Res
1993;
53:
1322-1327 |
| 3. | Klan R, Knispel HH, Meier T. Acetylsalicylic acid inhibition of N-butyl 4-hydroxybutyl nitrosamine-induced bladder carcinogenesis in rats. J Cancer Res Clin Oncol 1993; 119: 482-485[CrossRef][Medline]. |
| 4. | Robertson FM, Parnett ML, Joarder FS, Ross M, Abou-Issa HM, Alshafie G, et al. Ibuprofen-induced inhibition of cyclo-oxygenase gene expression and regression of rat mammary carcinomas. Cancer Letters 1998; 112: 165-175. |
| 5. |
Reddy BS, Rao CV, Rivenson A, Kelloff G.
Inhibitory effect of aspirin on azoxymethane-induced colon carcinogenesis in F344 rats.
Carcinogenesis
1993;
14:
1493-1497 |
| 6. | Van Staa T, Abenheim L. The quality of information on a UK database of primary care records: a study of hospitalisation due to hypoglycaemia and other conditions. Pharmacoepidemiol Drug Safety 1994; 3: 15-21. |
| 7. |
Giovannucci E, Egan KM, Hunter DJ, Stampfer MJ, Colditz GA, Willett WC, et al.
Aspirin and the risk of colorectal cancer in women.
New Engl J Med
1995;
333:
609-614 |
| 8. |
Paganini-Hill A, Hsu G, Ross RK, Henderson BE.
Aspirin use and incidence of large bowel cancer in a California retirement community.
J Natl Cancer Inst
1991;
83:
1182-1183 |
| 9. | Schreinermachers DM, Everson RB. Aspirin use and lung, colon and breast cancer incidence in a prospective study. Epidemiology 1994; 5: 138-146[Medline]. |
| 10. |
Gridley G, McLaughlin JK, Ekbom A, Klareskog L, Adami HO, Hacker DG, et al.
Incidence of cancer among patients with rheumatoid arthritis.
J Natl Cancer Inst
1993;
85:
307-301 |
| 11. | Isomaki HA, Hakulinen T, Joutsenlahti U. Excess risk of lymphomas, leukaemia and myeloma in patients with rheumatoid arthritis. J Chron Dis 1978; 31: 691-696[CrossRef][Medline]. |
| 12. | Funkhouser GM, Sharp GB. Aspirin and the reduced risk of esophageal carcinoma. Cancer 1995; 76: 116-119[CrossRef][Medline]. |
| 13. | Farrow DC, Vaughan TL, Hansten PD, Stanford JL, Risch HA, Gammon MD, et al. Use of aspirin and other nonsteroidal anti-inflammatory drugs and risk of esophageal and gastric cancer. Cancer Epidemiol Biomarkers Prev 1998; 7: 97-102[Abstract]. |
| 14. |
Egan KM, Stampfer MJ, Giovannucci E, Rosner BA, Colditz GA.
Prospective study of regular aspirin use and the risk of breast cancer.
J Natl Cancer Inst
1996;
88:
988-993 |
| 15. | Paganini-Hill A, Chao A, Ross RK, Henderson BE. Aspirin use and chronic disease: a cohort study of the elderly. BMJ 1989; 299: 1247-1250. |
| 16. | Harris RE, Namboodiri KK, Farrar WD. Non-steroidal anti-inflammatory drugs and breast cancer Epidemiology 1996; 7: 203-205[Medline]. |
| 17. | Friedman GD, Ury HK. Screening for possible drug carcinogenicity: second report of findings. J Natl Cancer Inst 1983; 71: 1165-1175. |
| 18. | Norrish AE, Jackson RT, McRae CU. Non-steroidal anti-inflammatory drugs and prostate cancer progression. Int J Cancer 1998; 77: 511-515[CrossRef][Medline]. |
| 19. | Langman MJS, Weil J, Wainwright P, Lawson DH, Rawlins MD, Logan RFA, et al. Risks of bleeding peptic ulcer associated with individual non-steroidal anti-inflammatory drugs. Lancet 1994; 343: 1075-1078[CrossRef][Medline]. |
| 20. | Eberhart CE, Coffey RJ, Radhika A, Giardiello FM, Ferrenbach S, DuBois RN. Upregulation of cyclooxygenase-2 gene expression in human colorectal adenomas and adenocarcinomas. Gastroenterology 1994; 107: 1183-1188[Medline]. |
| 21. |
Gustafson-Svard C, Lilja I, Hallbrook O, Sjodahl R.
Cyclooxygenase-1 and cyclooxygenase-2 gene expression in human colorectal adenocarcinomas and in azoxymethane-induced colonic tumours in rats.
Gut
1996;
38:
79-88 |
| 22. |
Hwang D, Scollard D, Byrne J, Levene E.
Expression of cyclooxygenase-1 and cyclooxygenase-2 in human breast cancer.
J Natl Cancer Inst
1998;
90:
455-460 |
| 23. |
Wilson KT, Fu S, Ramanujam KS, Meltzer SJ.
Increased expression of inducible nitric oxide synthase and cyclo oxygenase-2 in Barrett's oesophagus and associated adenocarcinomas.
Cancer Res
1998;
58:
2929-2934 |
| 24. |
Ristamaki A, Honkanen N, Jankala H, Sipponen P, Hankonen M.
Expression of cyclooxygenase-2 in human gastric carcinoma.
Cancer Res
1997;
57:
1276-1280 |
(Accepted 14 April 2000)
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