Screening for colorectal cancer

Using of endoscopic polypectomy in patients with diagnosed malignant colorectal polyp - The cross-sectional clinical study

The aim of this study was to evaluate the efficacy of endoscopic polypectomy as a therapeutic treatment for malignant alteration of colorectal polyps. In a 5-year research, 89 patients were included, who were tested and treated at the University Clinical Center Kragujevac, Kragujevac, Serbia, with the confirmed presence of malignant alteration polyps of the colon by colonoscopy, which were removed using the method of endoscopic polypectomy and confirmed by the histopathological examination of the entire polyp. After that, the same group of patients was monitored endoscopically within a certain period, controlling polypectomy locations and the occurrence of a possible remnant of the polyp, in the period of up to 2 years of polypectomy. We observed that, with an increasing size of polyps, there is also an increase in the percentage of the complexity of endoscopic resection and the appearance of remnant with histological characteristics of the invasive cancer. The highest percentage of incomplete endoscopic resection and the appearance of remnant with histological characteristics of the invasive cancer were shown at malignant altered polyps in the field of tubulovillous adenoma. Eighteen patients in total underwent the surgical intervention. In conclusion, our data support the high efficacy of endoscopic polypectomy for the removal of the altered malignant polyp.

Health needs as a priority of local authorities in Poland based on the example of implementation of health policy cancer programmes

INTRODUCTION

In developed countries, malignant tumours are the second most common cause of death after cardiovascular diseases. The estimates made by epidemiologists indicate that the incidence and death rate for malignant tumours all over the world, Poland included, will probably grow in the decades to come, specifically among patients who are over 65. The aim of the study was to evaluate how local government units address the health needs of citizens on the basis of an analysis of health policy programmes concerning malignant tumours completed in Poland in 2009-2014.

MATERIAL AND METHODS

The study was based on desk research. The data included in the annual reports submitted to the Minister of Health concerning completed health policy programmes were used.

RESULTS

The most programmes were completed in the Wielkopolskie and the Mazowieckie voivodeships, whereas the fewest were completed in the Kujawsko-Pomorskie and the Podlaskie voivodeships (χ2(15) = 2121.81, p < 0.001). The most programmes were completed by municipalities, followed by counties and, finally, self-governed voivodeships (Q(2) = 1967.90, p < 0.061). The majority of programmes concerned breast cancer and cervical cancer. There was no increase in the activity of local government units in terms of the number of implemented programmes, and a decreasing size of the population covered by the programmes.

CONCLUSIONS

There is a very high degree of differentiation in the involvement of particular voivodeships in fighting cancer regarding the number of implemented health programmes. There are various degrees of involvement of particular types of local government units in the implementation of programmes in the field of cancer. The repeatability of actions undertaken at the local and national level may indicate limited effectiveness of the policy to fight cancer. It is necessary to implement more programmes in the field of oncological diseases and to increase the population covered by these programmes.

Coloproctology procedure clinic: a novel service developed to reduce suffering of patients with bleeding per rectum

AIMS

Evaluation of the role and impact of introducing a dedicated coloproctology procedure clinic in tertiary referral colorectal unit.

METHODS

A retrospective analysis of 126 consecutive patients managed in the coloproctology clinic between March2015 and September 2016 was carried out. All patients were preselected for attendance based on symptom-based protocol.

RESULTS

Based on the information available in GP referrals, 126 patients with bleeding per rectum with low risk of cancer were re-triaged from the general outpatient to dedicated coloproctology procedure clinic. Those patients accounted for 14% of waiting list. The average waiting time to attend clinic was 27 months from referral to undergoing definitive procedure. A proctoscopy or/and rigid sigmoidoscopy was performed in patients. Seventy-nine (89.7%) patients were completely managed and discharged after attending their first visit. Sixty-seven (76%) patients had 2nd- or 3rd-degree haemorrhoids and were treated with rubber band ligation (RBL) or phenol injection in outpatient setting. Two patients had an anal fissure and were managed conservatively with medication. After clinic, follow-up was through telephone clinic. This avoids attendance physically in the hospital. Symptoms persisted in nine patients and were subsequently scheduled for colonoscopy, three had benign polyps. With the introduction of the procedure clinic, the waiting time from referral to treatment was reduced from 27 to 6 months (p < 0.05).

CONCLUSIONS

Establishing a dedicated "Coloproctology procedure clinic" is an effective strategy in reducing number of hospital visits per patient and hospital waiting list. This innovative clinic reduces utilisation of precious endoscopy unit resources. This ultimately will improve endoscopy efficiency.

HUMAN DNA QUANTIFICATION IN THE STOOLS OF PATIENTS WITH COLORECTAL CANCER

BACKGROUND

Colorectal cancer is one of the main cause of cancer in the world. Colonoscopy is the best screen method, however the compliance is less than 50%. Quantification of human DNA (hDNA) in the feces may be a possible screen non-invasive method that is a consequence of the high proliferation and exfoliation of cancer cells.

OBJECTIVE

To quantify the human DNA in the stools of patients with colorectal cancer or polyps.

METHODS

Fifty patients with CRC, 26 polyps and 53 with normal colonoscopy were included. Total and human DNA were analyzed from the frozen stools.

RESULTS

An increased concentration of hDNA in the stools was observed in colorectal cancer patients compared to controls and polyps. Tumors localized in the left side of the colon had higher concentrations of hDNA. There were no difference between polyps and controls. A cut off of 0.87 ng/mL of human DNA was determined for colorectal cancer patients by the ROC curve, with a sensitivity of 66% and a specificity of 86.8%. For polyps the cut off was 0.41, the sensitivity was 41% and the specificity 77.4%.

CONCLUSION

A higher concentration of hDNA had been found in colorectal cancer patients The quantification of hDNA from the stools can be a trial method for the diagnosis of colorectal cancer.

Gastrointestinal cancer screening: screening may release new research funding to improve health service also in routine clinics

We are far from having seen the ideal method of screening for colorectal cancer (CRC) and the downsides of screening have not been fully addressed. Funding of adequately sized screening trials with a 10-15-year perspective for endpoints CRC mortality and incidence is difficult to get. Also, with such time horizons, there will always be an ongoing study to be awaited before feeling obliged to invest in the next. New, promising screening methods may, however, emerge far more often than every 10th year, and the knowledge gap may easily widen unless research is made a key responsibility for any ongoing cancer screening program. Previous lost battles on screening research may be won if accepting that scientific evidence may be obtained within the framework of screening programs - provided that they are designed as platforms for Comparative Effectiveness Research (CER). Accepting that CER-based screening programs should be preferred to non-CER programs and seriously compete for their funding sources, then CER screening programs may not be considered so much as contenders for ordinary clinical research funds. Also, CER within a screening framework may benefit patients in routine clinics as shown by screening research in Nordic countries. The Nordic countries have been early contributors to research on CRC screening, but slow in implementing screening programs.

Risk of Colorectal Cancer by Subsite in a Swedish Prostate Cancer Cohort

BACKGROUND

The relationship between sex hormone-related treatment for prostate cancer and the risk of colorectal cancer is controversial.

METHODS

A prostate cancer cohort was initiated from the Swedish Cancer Registry of patients diagnosed between 1961 and 2008. Patients diagnosed with prostate cancer between 1961 and 1980 were generally treated with estrogen. The cohort diagnosed between 1981 and 2008 was further divided into 3 subcohorts of orchiectomy, prostatectomy, and other treatment. Standardized incidence ratios (SIRs) for developing colorectal adenocarcinoma were estimated and 95% confidence intervals (CIs) were used to compare relative risk among these patients and the general male population.

RESULTS

Of 601,542 person-years of follow-up, 1,698 cases of colorectal adenocarcinoma were identified. Compared with the general male population, no association was detected in the cohort diagnosed between 1961 and 1980, whereas an increased risk of colorectal adenocarcinoma was observed among patients diagnosed with prostate cancer who received treatments other than estrogen. Following bilateral orchiectomy, the SIR was 1.30 (95% CI: 1.14-1.47); after prostatectomy, the SIR was 1.22 (95% CI: 1.04-1.43); among those who received treatment other than estrogen, the SIR was 1.37 (95% CI: 1.29-1.45). The increased risks were more apparent in cases of adenocarcinoma of the distal colon and rectum than in the proximal colon.

CONCLUSIONS

Patients with prostate cancer undergoing bilateral orchiectomy, prostatectomy, or other treatments, including antiandrogen therapy and radiation, may be at increased risk for colorectal adenocarcinoma.

Systematic review and meta-analysis of the evidence for flexible sigmoidoscopy as a screening method for the prevention of colorectal cancer

BACKGROUND

Colorectal cancer is a significant cause of death. Removal of precancerous adenomas, and early detection and treatment of cancer, has been shown to reduce the risk of death. The aim of this review and meta-analysis was to determine whether flexible sigmoidoscopy (FS) is an effective population screening method for reducing mortality from colorectal cancer.

METHODS

MEDLINE (1946 to December 2012) and Embase (1980-2012, week 15) were searched for randomized clinical trials in which FS was used to screen non-symptomatic adults from a general population, and FS was compared with either no screening or any other alternative screening methods. Meta-analysis was carried out using a random-effects Mantel-Haenzsel model.

RESULTS

Twenty-four papers met the inclusion criteria, reporting results from 14 trials. Uptake of FS was usually lower than that for stool-based tests, although FS was more effective at detecting advanced adenoma and carcinoma. FS reduced the incidence of colorectal cancer after screening, and long-term mortality from colorectal cancer, compared with no screening in a selected population. Compared with stool-based tests in a general population, FS was associated with fewer interval cancers.

CONCLUSION

FS is efficacious at reducing colorectal cancer mortality compared with no screening. It is more effective at detecting advanced adenoma and carcinoma than stool-based tests. FS may be compromised by poorer uptake. Introduction of FS as a screening method should be done on a pilot basis in populations in which it is not currently used, and close attention should be paid to maximizing uptake. The relative risk of adverse events with FS compared with stool-based tests should be quantified, and its real-world effectiveness evaluated against the most effective stool-based tests.

Coverage and performance of colorectal cancer screening with the faecal occult blood test in Finland

INTRODUCTION

Mortality from colorectal cancer has been shown to decrease by repeated screening using faecal occult blood (FOB) testing in randomized screening trials. This report presents coverage and performance of organized screening among the general population in Finland.

METHODS

In 2004-2007, people aged 60-69 years were randomized into biennial screening and control arms. The screening test was a guaiac-based FOB test (Hemoccult) with dietary restriction and three test cards for six consecutive samples. Test positives were referred for full colonoscopy. The programme was launched in 2004 and subsequently it expanded over regions and age-cohorts.

RESULTS

In 2007, the programme covered one-third of the target population and 74,592 people had been invited for screening, of them 26,866 for the second round. Uptakes for the first and second rounds, respectively, were 62% and 68% in men and 77% and 80% in women. The proportion of test positives increased from 2.4% to 2.9% from the first to the second round and the positive predictive value for cancers decreased from 7.5% to 4.3%.

CONCLUSIONS

By 2007, organized colorectal cancer screening covered one-third of the target population in Finland. Implementation of screening measured with response rate was successful and met the criteria for a public health programme, but performance in terms of positive predictive value needs monitoring.

Survival of patients diagnosed with cancer in the Nordic countries up to 1999-2003 followed to the end of 2006. A critical overview of the results

Differences in Nordic cancer patient survival observed today originate from the 1970s, but were first identified in a mortality prediction from 1995. This paper provides timely comparisons of survival using NORDCAN, a database with comparable information from the Nordic cancer registries. Elucidation of the differences is important when monitoring cancer care generally and evaluating the impact of cancer plans.

MATERIAL AND METHODS

The NORDCAN database 1964-2003 with follow-up for death through 2006, was used to analyse incidence, mortality, and survival for all NORDCAN cancer sites. We analysed 5-year relative survival and excess mortality rates in the first three months and 2-5 years after diagnosis.

RESULTS

The time trends in survival 1989-2003 were largely similar between the Nordic countries with increases in 14 sites among men and 16 among women. In all countries the excess mortality rates were highest in the first three months after diagnosis, but decreased to similar levels across all countries 2-5 years after diagnosis. Comparing countries excess mortality was highest in Denmark irrespective of follow-up period. Lower survival was observed for Danish cancer patients in 23 of the 33 cancer sites in men and 26 of 35 sites in women. Low and similar levels of survival were observed for cancers of the oesophagus, lung, liver and pancreas, while an 8-10 percentage point difference in survival was found between countries for colorectal cancer.

CONCLUSION

The notable differences in Nordic cancer patient survival can be linked to national variations in risk factors, co-morbidity, and the implementation of screening. Improved treatment and primary prevention, in particular the targeting of tobacco and alcohol use, is required to improve cancer control. The recently-initiated cancer plans in Denmark and Norway are yet to show an observable effect on the corresponding cancer survival.

Trends in the overall survival of cancer patients diagnosed 1964-2003 in the Nordic countries followed up to the end of 2006: the importance of case-mix

AIM

Overall survival after cancer is frequently used when assessing the health care service performance as a whole. While used by the public, politicians, and the media, it is often discarded by clinicians and epidemiologists due to the heterogeneous mix of different cancers, risk factors and treatment modalities. We studied the trend in the Nordic 5-year relative survival and excess mortality for all cancers combined to see if the impact of case-mix and variations between countries in diagnostic methods such as breast screening and PSA testing could explain the lower survival in Denmark.

MATERIAL AND METHODS

From the NORDCAN database 1964-2003, we defined two cohorts of cancer patients, one excluding non-melanoma skin cancer and another also excluding breast and prostate cancer. We estimated age-standardised incidence and mortality rates, 5-year relative survival, and excess mortality rates for varying follow-up periods, and age-specific 5-year relative survival by country, sex and 5-year diagnostic period.

RESULTS

Prostate cancer is the main driver of the incidence increase in men, as do breast cancer in women, whereas cancer mortality in all Nordic countries is declining. The 5-year relative survival ratios are increasing in each Nordic population, but less so in Denmark. Country differences in survival stem mainly from follow-up periods immediately after diagnosis. Adjusting for the case-mix of diagnoses diminished differences a little while exclusion of breast and prostate cancer reduced the gap between countries in survival and excess mortality more considerably, yet post-adjustment, Danish patients still fare worse during the first three months after diagnosis.

CONCLUSION

Adjustment for case-mix and exclusion of sites where diagnostic procedures change the pattern of incidence is important when comparing overall cancer survival across countries, but the correction only explains part of the observed differences in survival. Other factors such as stage at presentation, co-morbidity, tobacco and alcohol consumption are likely contributors.

Influence of long-term colonoscopic surveillance on incidence of colorectal cancer and death from the disease in patients with precursors (adenomas)

Case-control studies and short term prospective studies have suggested that selected groups of patients with precursors of colorectal cancer may benefit from colonoscopic surveillance after initial removal of adenomas. The aim of the present study was to demonstrate such a possible benefit from long term (1-24 years) colonoscopic surveillance in a population of patients with all types of adenomas regardless of size and way of removal. Two thousand and forty-one patients with a first time diagnosis of colorectal adenoma were included in prospective surveillance between year 1978 and 2002. All adenomas were considered. Incidence of CRC and mortality from CRC was calculated, using age, sex, and calendar specific number of person years of follow-up for comparison with the standard Danish population. CRC was found in 27 patients, the expected number being 41 (RR 0.65, 95% CI 0.43-0.95). Three of the 27 patients died from CRC, the expected number being 25 (RR 0.12, 95% CI 0.03-0.36). A total of 6 289 colonoscopies resulted in severe complications in 20 patients and two died from complications. Long-term colonoscopic surveillance may reduce incidence of CRC as well as mortality in patients with sporadic adenomas. The benefit is reduced to a minor degree by complications from surveillance.

Survival, surgical management and perioperative mortality of colorectal cancer in the 21-year experience of a specialised registry

BACKGROUND AND AIMS

A general improvement of colorectal cancer prognosis has been observed. Reasons of this more favourable trend are diffusion of screening, advancements in molecular biology, new developments in chemotherapy and surgical techniques. Through the data of a colorectal cancer registry, we purposed to evaluate changes in surgical procedures for colorectal neoplasms and to analyse trends of perioperative mortality.

PATIENTS AND METHODS

Patients with colorectal cancer were registered from 1984 to 2004. The main surgical procedures were recorded and classified. Perioperative mortality was defined as death of patients within 1 month since the operation.

RESULTS

Regression analysis showed an increase over time of right and left hemicolectomy. Both colectomy and endoscopic polypectomy showed significant rise over time. In contrast, abdominoperineal operations dropped during the study period. A similar decrease was observed for palliative surgery. Perioperative mortality declined from 7-11% to 3-6% of all operations; main factors associated with perioperative mortality were presence of comorbidities, increasing age and advanced stage.

CONCLUSION

The better prognosis of patients with colorectal cancer was associated with changes of surgical techniques, with a tendency to prefer large operations over limited resections. Perioperative mortality showed a gradual decrease and is at present in the order of 3% to 6% of all operations.

Attitude of the Italian general population towards prevention and screening of the most common tumors, with special emphasis on colorectal malignancies

Screening and early diagnosis of cancer represent relatively recent tools in the long-lasting battle against tumors. If the American public opinion manifests its enthusiasm towards screening, the attitude of European is less well known. The purpose of the present study was to assess the level of knowledge and awareness of cancer screening (with particular emphasis on colorectal neoplasms) among middle-aged individuals. The study group consisted of 945 healthy individuals (489 men, 456 women, average age 57 +/- 12.4 years) who were asked to answer a series of questions about cancer screening and surveillance through a questionnaire presented by trained residents. Each interview lasted 20-30 min. Middle-aged Italians of both sexes seem to be aware of the fact that cancer is a frequent disease; moreover, many of the interviewed subjects believe almost all neoplasms are incurable. Diet, style of life, other environmental factors and familial factors are fully appreciated as relevant risk factors. The exact meaning of prevention was clear to less than half of the subjects. When various cancer sites were analyzed, the existence of preventive measures was well known for breast, cervical and prostate tumors, but their role was less clear for colorectal cancer. Only a fraction of the interviewed individuals were willing to undergo screening; the main reasons for refusal were lack of usefulness and fear of results. Among various tests, ultrasound and endoscopy were usually carried out in the presence of symptoms. Finally, multivariate analysis showed that the two factors significantly associated with the decision to undergo screening procedures were increasing age and level of education. The results of the study suggest that middle-aged Italian individuals, predominantly from Northern regions, have a correct perception of some aspects (frequency, risk factors) of cancer biology, whereas the knowledge of other aspects (outcome, prevention) remains poor or approximate. It follows that one of the main objectives of the Political Class should be to obtain a better education of overage individuals about cancer and the many problems related to this common disease.

Metabolite profiling of fecal water extracts from human colorectal cancer

Colorectal cancer is the second leading cause of cancer death in developed countries. There is a need for better preventive strategies to improve the outcome of this disease. The increasing availability of high-throughput methodologies opens up new possibilities for screening new markers. The application of NMR metabolic profiling to fecal water extracts has interesting potential as a diagnostic tool for detecting colorectal cancer. We obtained NMR metabolic profiles of fecal water extracts from patients with colorectal cancer and healthy individuals, to characterize possible differences between them and to identify potential diagnostic markers. Our results show that metabolic profiling of fecal water extracts is a cheap, reproducible and effective method for detecting colorectal cancer markers and therefore complements other stool-screening methods. A low concentration of short-chain fatty acids, such as acetate and butyrate, previously associated with the development of colorectal cancer, appears to be the most effective marker. Concentrations of proline and cysteine, which are major components of most colonic epithelium mucus glycoproteins, also display significant changes in samples from colorectal cancer. Differentiation between fecal water extracts from controls and patients with colorectal cancer by NMR spectroscopy combined with chemometric techniques opens up new possibilities for developing new, efficient, high-throughput screening protocols.

Test, episode, and programme sensitivities of screening for colorectal cancer as a public health policy in Finland: experimental design

OBJECTIVES

To report the sensitivities of the faecal occult blood test, screening episode, and screening programme for colorectal cancer and the benefits of applying a randomised design at the implementation phase of a new public health policy.

DESIGN

Experimental design incorporated in public health evaluation using randomisation at individual level in the target population.

SETTING

161 of the 431 Finnish municipalities in 2004-6.

PARTICIPANTS

106 000 adults randomised to screening or control arms. In total, 52 998 adults aged 60-64 in the screening arm received faecal occult blood test kits.

MAIN OUTCOME MEASURES

Test, episode, and programme sensitivities estimated by the incidence method and corrected for selective attendance and overdiagnosis.

RESULTS

The response for screening was high overall (70.8%), and significantly better in women (78.1%) than in men (63.3%). The incidence of cancer in the controls was somewhat higher in men than in women (103 v 93 per 100 000 person years), which was not true for interval cancers (42 v 49 per 100 000 person years). The sensitivity of the faecal occult blood test was 54.6%. Only a few interval cancers were detected among those with positive test results, hence the episode sensitivity of 51.3% was close to the test sensitivity. At the population level the sensitivity of the programme was 37.5%.

CONCLUSIONS

Although relatively low, the sensitivity of screening for colorectal cancer with the faecal occult blood test in Finland was adequate. An experimental design is a prerequisite for evaluation of such a screening programme because the effectiveness of preventing deaths is likely to be small and results may otherwise remain inconclusive. Thus, screening for colorectal cancer using any primary test modality should be launched in a public health programme with randomisation of the target population at the implementation phase.

Association of colorectal adenoma with other malignancies in Swedish families

Using the Swedish Family-Cancer Database covering over 11.5 million individuals, estimated relative risks (RRs) for colorectal adenoma were using Poisson's regression. The RR of colorectal adenoma was found to be increased among first-degree relatives of patients with colorectal cancer (2.72; 95% confidence interval=2.46-3.00) and among the offspring and siblings of patients with endometrial and prostate cancers. We also found an increased risk of colorectal adenoma for the offspring of individuals with stomach cancer and leukaemia, and for siblings of those with pancreatic cancer and multiple myeloma. Our results suggest that colorectal adenoma may share a genetic aetiology with cancer even at extracolorectal sites. Increases of colorectal adenoma in families affected by prostate cancer and acute leukaemia cannot be attributed to known cancer syndromes, although the play of chance cannot be excluded.

FDG-PET improves management of patients with colorectal liver metastases allocated for local treatment: a consecutive prospective study

BACKGROUND AND AIM

Colorectal cancer is a common cancer in the Nordic countries and 50% of the patients develop liver metastases. Liver resection may result in long term survival. Proper staging is therefore essential and CT is the standard imaging modality. We examined whether additional FDG-PET improves therapeutic management of patients with colorectal liver metastases.

PATIENTS AND METHODS

Fifty-four consecutive patients were enrolled. Each patient had a treatment plan made based on our standard evaluation. The patients then had a PET scan and the treatment plan was re-evaluated, taking these results into account.

RESULTS

In 76% of the cases, PET did not change the treatment plan due to complete concordance with CT. In another 19% of the cases, the plan was altered due to finding of more liver lesions by PET than by CT (four patients), fewer or no liver lesions (three patients), and extrahepatic lesions not visible on CT (three patients). In 5% of the cases, non-concordance between PET and CT did not change the therapeutic plan.

CONCLUSION

Pre-treatment FDG-PET, used supplementary to CT, improved the treatment plan in one fifth of the patients with colorectal liver metastases.

[Planning, implementation and evaluation of cancer screening programs]

Members of the Cancer Epidemiology Work Group within the German Epidemiology Society and Dr Antes of the German Cochrane Center will present a review of the epidemiological aspects of cancer screening programs. Prior to the implementation of a cancer screening program, there should be clear evidence from randomized controlled trials showing a disease-specific mortality reduction by screening. For target entities with the potential to reduce incident invasive cancers- such as cervical and colorectal cancer - the search of evidence should also include cancer incidence reduction. Monitoring of the screening program is essential and should include: the test, the assessment of test-positives, therapy or other interventions, and a cause of death evaluation. It is important to show that the benefit of a mortality reduction is not outweighed by adverse screening effects. In the past, German cancer screening activities were lacking essential components of screening programs like a central unit inviting the target population, standardized documentation and reporting as well as independent audits. The new Mammography Screening Program for the first time offers a screening test in Germany that is embedded in a quality monitoring program evaluating at least intermediate outcome parameters.

Colorectal cancer in middle-aged women in relation to hormonal status: a report from the Women's Health in the Lund Area (WHILA) study

OBJECTIVE

To delineate a perceived association of estradiol versus estradiol plus norethisterone hormone therapy on the prevalence of colorectal cancer in postmenopausal women.

METHODS

The Women's Health in the Lund Area (WHILA) project covers 10,766 women aged 50-60 years, living in the Lund area, Sweden. Out of this population, 6908 (64%) women completed questionnaires, underwent physical and laboratory assessments and had self-reported information regarding colorectal cancer. Four hundred and twenty-two (6%) were premenopausal (PM), 3600 (52%) were postmenopausal without hormone therapy (PM0), 2452 (36%) were postmenopausal with combined hormone therapy (PMT-HT) and 364 (5%) were postmenopausal with estrogen monotherapy (PMT-E).

RESULTS

There were 21 cases of colorectal cancer (0.3%), one in the PM group, 16 in the PM0 group, two in the PMT-HT group and another two in the PMT-E group. Colorectal cancer prevalence was lower in the PMT-HT than in the PM0 group (odds ratio (OR) = 0.18, 95% confidence interval (CI) = 0.04-0.80). However, for the PMT-E group, the OR (95% CI) was 1.02 (0.86-1.20). There was a positive association between low physical activity (p = 0.04), low parity (p = 0.02) and risk of colorectal cancer.

CONCLUSION

Combined hormone therapy seemed to be associated with a lower risk of colorectal cancer in postmenopausal women in contrast to estrogen monotherapy. Hence the progestin might have a protective role.

Patterns of cancer incidence, mortality, and prevalence across five continents: defining priorities to reduce cancer disparities in different geographic regions of the world

Efforts to reduce global cancer disparities begin with an understanding of geographic patterns in cancer incidence, mortality, and prevalence. Using the GLOBOCAN (2002) and Cancer Incidence in Five Continents databases, we describe overall cancer incidence, mortality, and prevalence, age-adjusted temporal trends, and age-specific incidence patterns in selected geographic regions of the world. For the eight most common malignancies-cancers of lung, breast, colon and rectum, stomach, prostate, liver, cervix, and esophagus-the most important risk factors, cancer prevention and control measures are briefly reviewed. In 2002, an estimated 11 million new cancer cases and 7 million cancer deaths were reported worldwide; nearly 25 million persons were living with cancer. Among the eight most common cancers, global disparities in cancer incidence, mortality, and prevalence are evident, likely due to complex interactions of nonmodifiable (ie, genetic susceptibility and aging) and modifiable risk factors (ie, tobacco, infectious agents, diet, and physical activity). Indeed, when risk factors among populations are intertwined with differences in individual behaviors, cultural beliefs and practices, socioeconomic conditions, and health care systems, global cancer disparities are inevitable. For the eight most common cancers, priorities for reducing cancer disparities are discussed.