Hydrochlorothiazide use is strongly associated with risk of lip cancer

BACKGROUND

The diuretic hydrochlorothiazide is amongst the most frequently prescribed drugs in the United States and Western Europe, but there is suggestive evidence that hydrochlorothiazide use increases the risk of lip cancer.

OBJECTIVES

To study the association between use of hydrochlorothiazide and squamous cell carcinoma of the lip.

METHODS

We conducted a case-control study using Danish nationwide registry data. From the Cancer Registry (2004-2012), we identified 633 case patients with squamous cell carcinoma (SCC) of the lip and matched them to 63 067 population controls using a risk-set sampling strategy. Hydrochlorothiazide use (1995-2012) was obtained from the Prescription Registry and defined according to cumulative use. Applying conditional logistic regression, we calculated odds ratios (ORs) for SCC lip cancer associated with hydrochlorothiazide use, adjusting for predefined potential confounders obtained from demographic, prescription and patient registries.

RESULTS

Ever-use of hydrochlorothiazide was associated with an adjusted OR for SCC lip cancer of 2.1 (95% confidence interval (CI): 1.7-2.6), increasing to 3.9 (95%CI: 3.0-4.9) for high use (≥25 000 mg). There was a clear dose-response effect (P < 0.001), with the highest cumulative dose category of hydrochlorothiazide (≥100 000 mg) presenting an OR of 7.7 (95%CI: 5.7-10.5). No association with lip cancer was seen with use of other diuretics or nondiuretic antihypertensives. Assuming causality, we estimated that 11% of the SCC lip cancer cases could be attributed to hydrochlorothiazide use.

CONCLUSIONS

Hydrochlorothiazide use is strongly associated with an increased risk of lip cancer.

Use of antidepressants and risk of epithelial ovarian cancer

Antidepressants are widely prescribed among women to treat depression and anxiety disorders, but studies of their effects on gynecological cancer risk are sparse. We assessed associations between various antidepressants and risk of epithelial ovarian cancer. By using Danish nationwide registers, we identified all women (cases) aged 30-84 years with incident epithelial (serous, endometrioid, clear cell or mucinous) ovarian cancer during 2000-2011 (n = 4,103) and matched each case to 20 population controls (n = 58,706) by risk-set matching. Data on drug use (including tricyclic and related antidepressants, selective serotonin reuptake inhibitors, other antidepressants, and potential confounder drugs), medical and reproductive history and socioeconomic parameters, were obtained from nationwide registries. We used conditional logistic regression models to estimate adjusted odds ratios (ORs) and two-sided 95% confidence intervals (CIs) for epithelial ovarian cancer associated with antidepressive drug use. Compared with non-use, use of selective serotonin reuptake inhibitors was associated with a decreased risk of ovarian cancer (OR, 0.85; 95% CI, 0.74-0.96), whereas the associations for other antidepressants were close to unity [tricyclic and related antidepressants: OR, 0.99 (95% CI, 0.78-1.26); other antidepressants: OR, 1.05 (95% CI, 0.76-1.46)]. For individual types of SSRI, reduced ORs were observed for citalopram OR, 0.78 (95% CI, 0.66-0.93), paroxetine 0.79 (95% CI, 0.56-1.12) and sertraline 0.80 (95% CI, 0.60-1.08). Among postmenopausal women, the inverse association was restricted to users of menopausal hormone therapy. In conclusion, use of selective serotonin reuptake inhibitors was associated with a decreased risk of epithelial ovarian cancer; thereby implying potential chemopreventive properties of these drugs.

Postdiagnosis Statin Use and Mortality in Danish Patients With Prostate Cancer

Purpose Increasing evidence indicates that statin use may reduce mortality from prostate cancer. In this work, we examined whether postdiagnosis statin use was associated with reduced cancer-specific mortality or all-cause mortality among patients with prostate cancer in Denmark. Material and Methods From nationwide Danish registries, we identified all patients with incident prostate adenocarcinoma from 1998 to 2011 and retrieved data on tumor and patient characteristics, drug use, and primary treatment. We defined postdiagnosis use (two or more prescriptions) of statins as a time-varying covariate with 1-year lag. Cox proportional hazards regression models used to compute hazard ratios (HRs) for prostate cancer-specific mortality and all-cause mortality through 2013 associated with postdiagnosis statin use. In secondary and sensitivity analyses, we assessed statin use within exposure periods of 1 year or 5 years after prostate cancer diagnosis and evaluated the influence of prediagnosis statin use. Results Among 31,790 patients, 7,365 died of prostate cancer and 11,811 died from other causes during a median follow-up of 2.8 years (interquartile range, 1.3 to 5.1 years) from 1 year after diagnosis. Postdiagnosis statin use was associated with adjusted HRs of 0.83 (95% CI, 0.77 to 0.89) for prostate cancer mortality and 0.81 (95% CI, 0.76 to 0.85) for all-cause mortality. Similar results were observed in 1-year and 5-year sensitivity analyses. No substantial effect measure modification was found with estimated dose or type of statin, clinical stage, Gleason score, or with prediagnosis statin use; however, patients who were diagnosed early in the study period or who underwent radical prostatectomy or endocrine therapy exhibited slightly lower HRs for prostate cancer mortality with postdiagnosis statin use than did those in the overall analyses. Conclusion Postdiagnosis statin use was associated with reduced mortality from prostate cancer; however, it remains to be established whether this association is causal.

External adjustment of unmeasured confounders in a case-control study of benzodiazepine use and cancer risk

AIMS

Previous studies have reported diverging results on the association between benzodiazepine use and cancer risk.

METHODS

We investigated this association in a matched case-control study including incident cancer cases during 2002-2009 in the Danish Cancer Registry (n = 94 923) and age- and sex-matched (1:8) population controls (n = 759 334). Long-term benzodiazepine use was defined as ≥500 defined daily doses 1-5 years prior to the index date. We implemented propensity score (PS) calibration using external information on confounders available from a survey of the Danish population. Two PSs were used: The error-prone PS using register-based confounders and the calibrated PS based on both register- and survey-based confounders, retrieved from the Health Interview Survey.

RESULTS

Register-based data showed that cancer cases had more diagnoses, higher comorbidity score and more co-medication then population controls. Survey-based data showed lower self-rated health, more self-reported diseases, and more smokers as well as subjects with sedentary lifestyle among benzodiazepine users. By PS calibration, the odds ratio for cancer overall associated with benzodiazepine use decreased from 1.16 to 1.09 (95% confidence interval 1.00-1.19) and for smoking-related cancers from 1.20 to 1.10 (95% confidence interval 1.00-1.21).

CONCLUSION

We conclude that the increased risk observed in the solely register-based study could partly be attributed to unmeasured confounding.

Statin use and mortality among ovarian cancer patients: A population-based cohort study

Statin use has been suggested to improve prognosis in cancer patients, however, for ovarian cancer, the evidence is sparse. From the Danish Cancer Registry, we identified patients aged 30-84 years with a histologically verified first diagnosis of epithelial ovarian cancer between 2000 and 2013. Data on filled prescriptions, death, and potential confounding factors were obtained from nationwide registers. Cox proportional hazard regression models were used to calculate hazard ratios (HRs) and 95% confidence intervals (CIs) for the association between post-diagnostic statin use and all-cause or ovarian cancer-specific mortality. Among 4,419 patients with epithelial ovarian cancer, post-diagnostic statin use was not statistically significantly associated with all-cause (HR: 0.90, 95% CI: 0.78-1.04) or ovarian cancer-specific mortality (HR: 0.90, 95% CI: 0.76-1.08). There was little evidence of a dose-response relationship and the neutral associations persisted in sensitivity analyses. In women with endometrioid or clear cell tumour histology, cancer-specific mortality was reduced by 30-40% among statin users compared to non-users, however the analyses were limited by small numbers. Significantly reduced mortality with statin use was observed in subcohorts of new users of statins and of patients not using low-dose aspirin. In conclusion, we found no strong evidence of an association between post-diagnostic statin use and reduced mortality in ovarian cancer patients. However, our finding of potential differential susceptibility to statins among patients with different histologic types of ovarian cancer warrants further evaluation.

Socioeconomic position and mortality among patients with prostate cancer: influence of mediating factors

INTRODUCTION

Men with low socioeconomic position experience higher mortality after a prostate cancer diagnosis compared to men with a higher socioeconomic position, however, the specific mediators of this association are unclear. We therefore evaluated the influence of potential mediators on the association between socioeconomic position, and prostate cancer-specific and all-cause death in prostate cancer patients.

MATERIALS AND METHODS

We conducted a cohort study of prostate cancer patients in the Danish Diet, Cancer and Health study. All patients completed questionnaires and anthropometric measurements at enrollment. Information on educational level, income, comorbidity and vital status was obtained by linkage to Danish nationwide registries. Clinical data and anthropometric measures were collected from medical records at diagnosis. Cox proportional hazard models were used to compute hazard ratios (HR) for all-cause and prostate cancer-specific death according to socioeconomic position and potential mediators.

RESULTS

We included 953 prostate cancer patients identified among 27 179 male participants in the Diet, Cancer and Health study who were followed for a median of 6.5 years (interquartile range 6.4-11.2 years). Patients with low socioeconomic position were more often overweight or obese at baseline. Low socioeconomic position was associated with increased prostate cancer-specific and all-cause death. The increased mortality could largely be explained by tumor aggressiveness, comorbidity, treatment and metabolic indicators, except for patients in the lowest income group.

DISCUSSION

Our study confirmed the a priori assumption that socioeconomic position is associated with increased mortality after prostate cancer. The increased mortality could largely be explained by lifestyle and clinical parameters.

Propranolol and survival from breast cancer: a pooled analysis of European breast cancer cohorts

BACKGROUND

Preclinical studies have demonstrated that propranolol inhibits several pathways involved in breast cancer progression and metastasis. We investigated whether breast cancer patients who used propranolol, or other non-selective beta-blockers, had reduced breast cancer-specific or all-cause mortality in eight European cohorts.

METHODS

Incident breast cancer patients were identified from eight cancer registries and compiled through the European Cancer Pharmacoepidemiology Network. Propranolol and non-selective beta-blocker use was ascertained for each patient. Breast cancer-specific and all-cause mortality were available for five and eight cohorts, respectively. Cox regression models were used to calculate hazard ratios (HR) and 95% confidence intervals (CIs) for cancer-specific and all-cause mortality by propranolol and non-selective beta-blocker use. HRs were pooled across cohorts using meta-analysis techniques. Dose-response analyses by number of prescriptions were also performed. Analyses were repeated investigating propranolol use before cancer diagnosis.

RESULTS

The combined study population included 55,252 and 133,251 breast cancer patients in the analysis of breast cancer-specific and all-cause mortality respectively. Overall, there was no association between propranolol use after diagnosis of breast cancer and breast cancer-specific or all-cause mortality (fully adjusted HR = 0.94, 95% CI, 0.77, 1.16 and HR = 1.09, 95% CI, 0.93, 1.28, respectively). There was little evidence of a dose-response relationship. There was also no association between propranolol use before breast cancer diagnosis and breast cancer-specific or all-cause mortality (fully adjusted HR = 1.03, 95% CI, 0.86, 1.22 and HR = 1.02, 95% CI, 0.94, 1.10, respectively). Similar null associations were observed for non-selective beta-blockers.

CONCLUSIONS

In this large pooled analysis of breast cancer patients, use of propranolol or non-selective beta-blockers was not associated with improved survival.

The Danish Prostate Cancer Database

Aim of database

The Danish Prostate Cancer Database (DAPROCAdata) is a nationwide clinical cancer database that has prospectively collected data on patients with incident prostate cancer in Denmark since February 2010. The overall aim of the DAPROCAdata is to improve the quality of prostate cancer care in Denmark by systematically collecting key clinical variables for the purposes of health care monitoring, quality improvement, and research.

Study population

All Danish patients with histologically verified prostate cancer are included in the DAPROCAdata.

Main variables

The DAPROCAdata registers clinical data and selected characteristics for patients with prostate cancer at diagnosis. Data are collected from the linkage of nationwide health registries and supplemented with online registration of key clinical variables by treating physicians at urological and oncological departments. Main variables include Gleason scores, cancer staging, prostate-specific antigen values, and therapeutic measures (active surveillance, surgery, radiotherapy, endocrine therapy, and chemotherapy).

Descriptive data

In total, 22,332 patients with prostate cancer were registered in DAPROCAdata as of April 2015. A key feature of DAPROCAdata is the routine collection of patient-reported outcome measures (PROM), including data on quality-of-life (pain levels, physical activity, sexual function, depression, urine and fecal incontinence) and lifestyle factors (smoking, alcohol consumption, and body mass index). PROM data are derived from questionnaires distributed at diagnosis and at 1-year and 3-year follow-up. Hitherto, the PROM data have been limited by low completeness (26% among newly diagnosed patients in 2014).

Conclusion

DAPROCAdata is a comprehensive, yet still young clinical database. Efforts to improve data collection, data validity, and completeness are ongoing and of high priority.

Use of sildenafil or other phosphodiesterase inhibitors and risk of melanoma

BACKGROUND

Phosphodiesterase 5A inhibitors (PDEIs), a common treatment for erectile dysfunction, were recently linked to an increased risk of melanoma.

METHODS

We conducted two parallel case-control studies, using the Danish Nationwide Health Registries (DNHR) and the Kaiser Permanente Northern California (KPNC) electronic health records. Identifying men with histologically verified melanoma (cases) matched on birth year to 10 cancer-free controls, we estimated odds ratios (OR) for melanoma associated with high use of PDEIs (⩾100 tablets filled), adjusting for available confounders.

RESULTS

We identified 7045 DNHR and 2972 KPNC cases with invasive melanoma. The adjusted OR for invasive melanoma associated with high PDEI use was 1.22 (95% confidence interval (CI), 0.99-1.49) in DNHR and 0.95 (95% CI, 0.78-1.14) in KPNC. Odds ratios were highest for localised invasive melanoma in DNHR (OR, 1.21) and melanoma in situ in KPNC (OR, 1.15), and lowest for non-localised disease in both populations (ORs 0.75 and 0.61, respectively). The increased ORs were slightly attenuated upon adjustment for markers of health-care utilisation.

CONCLUSIONS

We found little evidence for a causal association between PDEI use and risk of melanoma. The marginally increased risk of early stage disease likely resulted from more frequent health-care contacts among PDEI users.

Low-dose aspirin or other nonsteroidal anti-inflammatory drug use and prostate cancer risk: a nationwide study

PURPOSE

Increasing evidence suggests that aspirin use may protect against prostate cancer. In a nationwide case-control study, using Danish high-quality registry data, we evaluated the association between the use of low-dose aspirin or other nonsteroidal anti-inflammatory drugs (NSAIDs) and the risk of prostate cancer.

METHODS

We identified 35,600 patients (cases) with histologically verified prostate cancer during 2000-2012. Cases were matched to 177,992 population controls on age and residence by risk-set sampling. Aspirin and nonaspirin NSAID exposure was defined by type, estimated dose, duration, and consistency of use. We used conditional logistic regression to estimate odds ratios (ORs), with 95 % confidence intervals (CIs), for prostate cancer associated with low-dose aspirin (75-150 mg) or nonaspirin NSAID use, adjusted for potential confounders.

RESULTS

Use of low-dose aspirin was associated with an OR for prostate cancer of 0.94 (95 % CI 0.91-0.97). Slightly lower ORs were seen with increasing cumulative amount, duration, and consistency of low-dose aspirin use (continuous use, ≥5 years: OR 0.89; 95 % CI 0.82-0.97; ≥10 years: OR 0.86; 95 % CI 0.70-1.06). Nonaspirin NSAID use was associated with a slightly increased OR for prostate cancer (1.13; 95 % CI 1.10-1.15); however, this association was confined to localized disease and did not vary materially with amount, duration, or consistency of nonaspirin NSAID use.

CONCLUSIONS

Our study indicates that long-term, consistent low-dose aspirin use may provide modest protection against prostate cancer. The slightly increased risk of only localized prostate cancer with nonaspirin NSAID use suggests a noncausal explanation of the observed association.

Primary mucosal melanoma of the head and neck in Denmark, 1982-2012: Demographic and clinical aspects. A retrospective DAHANCA study

Background The study was performed to determine the epidemiological, clinical, and histopathological characteristics and prognosis of primary mucosal melanoma of the head and neck (MMHN) in Denmark. Material and methods This was a national retrospective multicenter study of patients diagnosed with MMHN between 1982 and 2012 in Denmark. Data were retrieved from national databases and patient records. Incidence trends were examined for the entire period. We prepared survival curves and performed univariate and multivariate analysis for the period 1992-2012 to identify possible prognostic factors. Results No significant trends in incidence were found in the study period. The three-year overall and disease-free survival rates for MMHN were 46.5% and 35.5%, respectively. Negative margins was an independent predictor of disease-free survival, and age below 65, absence of distant metastases, and low overall TNM stage were predictors of overall survival. Radiotherapy did not improve survival significantly. Recurrence rates were high, even for patients with negative margins. Conclusions MMHN remains a rare disease with a poor prognosis, particularly for patients aged over 65, those with distant metastasis, and those with advanced TNM stage. Importantly, the rate of recurrence is lowest in patients with negative margins.

Repurposing Cationic Amphiphilic Antihistamines for Cancer Treatment

Non-small cell lung cancer (NSCLC) is one of the deadliest cancers worldwide. In search for new NSCLC treatment options, we screened a cationic amphiphilic drug (CAD) library for cytotoxicity against NSCLC cells and identified several CAD antihistamines as inducers of lysosomal cell death. We then performed a cohort study on the effect of CAD antihistamine use on mortality of patients diagnosed with non-localized cancer in Denmark between 1995 and 2011. The use of the most commonly prescribed CAD antihistamine, loratadine, was associated with significantly reduced all-cause mortality among patients with non-localized NSCLC or any non-localized cancer when compared with use of non-CAD antihistamines and adjusted for potential confounders. Of the less frequently described CAD antihistamines, astemizole showed a similar significant association with reduced mortality as loratadine among patients with any non-localized cancer, and ebastine use showed a similar tendency. The association between CAD antihistamine use and reduced mortality was stronger among patients with records of concurrent chemotherapy than among those without such records. In line with this, sub-micromolar concentrations of loratadine, astemizole and ebastine sensitized NSCLC cells to chemotherapy and reverted multidrug resistance in NSCLC, breast and prostate cancer cells. Thus, CAD antihistamines may improve the efficacy of cancer chemotherapy.

•

Use of cationic amphiphilic antihistamines is associated with reduced mortality among patients with non-localized cancer.

•

Clinically relevant concentrations of cationic amphiphilic antihistamines sensitize cancer cells to chemotherapy.

•

Clinically relevant concentrations of cationic amphiphilic antihistamines revert multidrug resistance.

Research Context Cationic amphiphilic drugs (CADs) induce lysosomal membrane permeabilization and cell death preferentially in cancer cells. Here, we show that antihistamines with CAD structure, i.e. astemizole, ebastine and loratadine, sensitize cancer cells to chemotherapy and revert multidrug resistance even at low, clinically relevant concentrations. The significance of these experimental findings is supported by an association between CAD antihistamine use and reduced mortality among patients diagnosed with non-localized cancer, especially among those receiving concurrent chemotherapy. These findings are immediately translatable to clinical trials, as loratadine and ebastine, are safe, inexpensive and approved for clinical use.

Cancer incidence in persons with type 1 diabetes: a five-country study of 9,000 cancers in type 1 diabetic individuals

AIMS/HYPOTHESIS

An excess cancer incidence of 20-25% has been identified among persons with diabetes, most of whom have type 2 diabetes. We aimed to describe the association between type 1 diabetes and cancer incidence.

METHODS

Persons with type 1 diabetes were identified from five nationwide diabetes registers: Australia (2000-2008), Denmark (1995-2014), Finland (1972-2012), Scotland (1995-2012) and Sweden (1987-2012). Linkage to national cancer registries provided the numbers of incident cancers in people with type 1 diabetes and in the general population. We used Poisson models with adjustment for age and date of follow up to estimate hazard ratios for total and site-specific cancers.

RESULTS

A total of 9,149 cancers occurred among persons with type 1 diabetes in 3.9 million person-years. The median age at cancer diagnosis was 51.1 years (interquartile range 43.5-59.5). The hazard ratios (HRs) (95% CIs) associated with type 1 diabetes for all cancers combined were 1.01 (0.98, 1.04) among men and 1.07 (1.04, 1.10) among women. HRs were increased for cancer of the stomach (men, HR 1.23 [1.04, 1.46]; women, HR 1.78 [1.49, 2.13]), liver (men, HR 2.00 [1.67, 2.40]; women, HR 1.55 [1.14, 2.10]), pancreas (men, HR 1.53 [1.30, 1.79]; women, HR 1.25 [1.02,1.53]), endometrium (HR 1.42 [1.27, 1.58]) and kidney (men, HR 1.30 [1.12, 1.49]; women, HR 1.47 [1.23, 1.77]). Reduced HRs were found for cancer of the prostate (HR 0.56 [0.51, 0.61]) and breast (HR 0.90 [0.85, 0.94]). HRs declined with increasing diabetes duration.

CONCLUSION

Type 1 diabetes was associated with differences in the risk of several common cancers; the strength of these associations varied with the duration of diabetes.

Clinical Features in a Danish Population-Based Cohort of Probable Multiple System Atrophy Patients

BACKGROUND

Multiple system atrophy (MSA) is a rare, sporadic and progressive neurodegenerative disorder. We aimed to describe the clinical features of Danish probable MSA patients, evaluate their initial response to dopaminergic therapy and examine mortality.

METHODS

From the Danish National Patient Registry, we identified 782 patients diagnosed with conditions potentially compatible with probable MSA (International Classification of Diseases, version 10 (ICD-10) codes G23.2, G23.8 and G23.9) during 1994-2009. Through medical record review, we narrowed our sample to 115 patients who fulfilled the criteria for probable MSA. We recorded clinical features, examined differences by MSA subtype and used Kaplan-Meier survival analysis to examine mortality.

RESULTS

The mean age at onset of patients with probable MSA was 60.2 years (range 36-75 years) and mean time to wheelchair dependency was 4.7 years (range 0-15 years). One-third of patients experienced a transient improvement in motor symptoms with use of levodopa. Median survival from disease onset was 6.9 years (range 1-16 years, 95% CI 6.3-7.5) with no apparent variation according to gender or subtype.

CONCLUSIONS

Our nationwide approach corroborated that MSA is associated with diverse and grave symptoms, only limited response to levodopa, and poor prognosis.

Identification of Associations Between Prescribed Medications and Cancer: A Nationwide Screening Study

Purpose

We present a systematic screening for identifying associations between prescribed drugs and cancer risk using the high quality Danish nationwide health registries.

Methods

We identified all patients (cases) with incident cancer in Denmark during 2000–2012 (n = 278,485) and matched each case to 10 controls. Complete prescription histories since 1995 were extracted. Applying a two-phased case–control approach, we first identified drug classes or single drugs associated with an increased or decreased risk of 99 different cancer types, and further evaluated potential associations by examining specificity and dose–response patterns.

Findings

22,125 drug–cancer pairs underwent evaluation in the first phase. Of 4561 initial signals (i.e., drug–cancer associations), 3541 (78%) failed to meet requirements for dose–response patterns and specificity, leaving 1020 eligible signals. Of these, 510 signals involved the use of single drugs, and 33% (166 signals) and 67% (344 signals) suggested a reduced or an increased cancer risk, respectively. While a large proportion of the signals were attributable to the underlying conditions being treated, our algorithm successfully identified well-established associations, as well as several new signals that deserve further investigation.

Conclusion

Our results provide the basis for future targeted studies of single associations to capture novel carcinogenic or chemopreventive effects of prescription drugs.

•

We conducted a nationwide register-based screening study aimed at identifying potential drug–cancer associations.

•

Screening initiatives using registry data may serve as an important tool for identification of drug–cancer associations.

•

Future research should address the signals provided by our study, i.e. in studies of the single putative associations.

The use of prescription drugs may influence the risk of developing cancer. In this study, we sought to identify such effects by combining data from Danish nationwide health care registries on drug use and cancer occurrence. We compared drug use among 278,485 cancer patients to use among cancer-free control individuals. Thereby, we identified 1020 putative drug–cancer associations. Future research should address the signals provided by our study, either as studies focusing on single associations or as a replication of our study using other data sources.

European Code against Cancer 4th Edition: Medical exposures, including hormone therapy, and cancer

The 4th edition of the European Code against Cancer recommends limiting - or avoiding when possible - the use of hormone replacement therapy (HRT) because of the increased risk of cancer, nevertheless acknowledging that prescription of HRT may be indicated under certain medical conditions. Current evidence shows that HRT, generally prescribed as menopausal hormone therapy, is associated with an increased risk of cancers of the breast, endometrium, and ovary, with the risk pattern depending on factors such as the type of therapy (oestrogen-only or combined oestrogen-progestogen), duration of treatment, and initiation according to the time of menopause. Carcinogenicity has also been established for anti-neoplastic agents used in cancer therapy, immunosuppressants, oestrogen-progestogen contraceptives, and tamoxifen. Medical use of ionising radiation, an established carcinogen, can provide major health benefits; however, prudent practices need to be in place, with procedures and techniques providing the needed diagnostic information or therapeutic gain with the lowest possible radiation exposure. For pharmaceutical drugs and medical radiation exposure with convincing evidence on their carcinogenicity, health benefits have to be balanced against the risks; potential increases in long-term cancer risk should be considered in the context of the often substantial and immediate health benefits from diagnosis and/or treatment. Thus, apart from HRT, no general recommendations on reducing cancer risk were given for carcinogenic drugs and medical radiation in the 4th edition of European Code against Cancer. It is crucial that the application of these measures relies on medical expertise and thorough benefit-risk evaluation. This also pertains to cancer-preventive drugs, and self-medication with aspirin or other potential chemopreventive drugs is strongly discouraged because of the possibility of serious, potentially lethal, adverse events.