General practitioners’ preferences with regard to colorectal cancer screening organisation Colon cancer screening medico-legal aspects

Objective

French health authorities put general practitioners at the heart of the colorectal cancer screening. This position raises organisational issues and poses medico-legal problems for the professionals and institutions involved in these campaigns, related to the key concepts of medical decisions and suitability of standards. The objective of our study is to reveal the preferences of general practitioners related to colorectal cancer screening organisation with regard to the medico-legal risk

Who attends skin cancer screening in Western Australia? Results from the Lions Cancer Institute skin cancer screening program

OBJECTIVE: To examine the characteristics of persons attending a skin cancer screening clinic in Western Australia and compare the effectiveness of screening in different socio-demographic subgroups. METHODS: Questionnaires were completed by 5,950 self-selected participants who voluntarily attended the Western Australian Lions Cancer Institute's targeted skin cancer screening clinics during the period 1996-2003. A risk assessment technique was used to identify individuals at high risk of developing melanoma. Provisional diagnoses of suspicious lesions were given at the screening by a medical specialist. Suspicious lesions were later matched with histopathologically confirmed malignant melanomas reported to the Western Australia Cancer Registry. RESULTS: Fifty-seven per cent of attendees were female. The mean age of attendees was 53 years. The yield of suspicious malignant melanomas detected was 24.7 per 1,000 participants screened; the yield of confirmed malignant melanomas detected was 3.0 per 1,000 participants screened. Persons over 50 years of age were three times more likely to have a histopathologically confirmed malignant melanoma detected at the screening than those younger than 50 years (p = 0.049). CONCLUSIONS: The yield of confirmed melanomas detected by the Lions Cancer Institute is among the highest reported by a skin cancer screening program. This may have been attributable to the risk assessment technique used by the program. IMPLICATIONS: A free community skin cancer screening program that targets high-risk individuals can detect melanomas.     

Is the mass screening for prostate cancer justifiable?

In Hungary, prostate cancer is a major public health problem, therefore screening should be considered to reduce the number of deaths. Screening tests are available, i.e. prostate-specific antigen (PSA) and digital-rectal examination, nevertheless their sensitivity, specificity and positive predictive value are far from being perfect. Evidences from non-randomized screening trials suggest possible benefit but randomized controlled trials are still needed for conclusive evidence. The screening might cause more harm than good due to overdiagnosis and overtreatment as a result of limited specificity of the test. According to authors' point of view, opportunistic screening as part of diagnostics of patients having symptoms indicative of prostatic disorder is fully justified but mass screening of population of average risk should not be introduced until supportive evidence is available from the ongoing randomized-controlled screening trials.     

Tailored breast cancer screening with ultrasound and MRI?

The ACRIN 6666 trial has shown that the addition of ultrasound or MRI to mammography screening detects more breast cancers in women with dense breasts and at least one other breast cancer risk factor. This higher detection yield is accompanied by an increase in false-positive findings. Unfortunately, this study was not randomized into groups with and without the addition of ultrasound and MRI. It is therefore impossible to investigate if the improved detection rate also results in a smaller number of interval tumours which would be the best indication of the ultimate goal - a decrease in breast cancer mortality. Before any new and costly imaging is added to the breast cancer screening program, it is necessary to investigate if this will not merely increase the detection of indolent tumours. If additional imaging is implemented too hastily it will be hard to turn it back, and impossible to assess it in a randomized study.     

Is lung cancer screening using CT a good idea?

Screening with low-dose computed tomography reduces lung cancer mortality. However, the high incidence of false positive screening results, the uncertainty of the duration of screening and the lack of a cost-effectiveness analysis should be overcome before introduction in a daily clinical practice.     

Is screening for anal cancer warranted in homosexual men?

Some investigators have proposed screening homosexual men for anal cancer and its probable precursor, high grade anal intraepithelial neoplasia (AIN). Using widely accepted criteria for the introduction of screening programmes, this paper reviews the current evidence for screening for this condition in this high risk population and highlights areas where additional research is required. While it is accepted that the incidence of anal cancer is at least 20 times higher in homosexual men than the general population, the natural history of anal cancer and its precise relationship with AIN is not clearly understood. Anal intraepithelial neoplasia is a very highly prevalent disease among homosexual men, but little is known about what predicts progression to invasive disease. The screening tests, exfoliate cytology and high resolution anoscopy, have a sensitivity of between 45 and 70%. Treatment options for AIN are limited by morbidity and high recurrence rates and there are no randomised controlled trials studying the efficacy of therapeutic agents or surgery for high grade AIN, although immunotherapies show very early promise. Theoretically, early detection may lead to better treatment outcomes. Studies of the potential negative consequences of screening programmes on the homosexual population are needed. The currently available data does not support the implementation of a screening programme for AIN and anal cancer in homosexual men in Australia.     

Breast cancer screening: Should it be introduced and how?

Summary This brief discussion of the papers by Gästrin and Paccaud is looking at differences in the results of different study types. Introducing screening means changing unsystematic to systematic screening: only the latter has been shown to be effective. The comparison between randomized trials, and follow-up of acceptors only, suggests that the non-acceptors have much higher risks. Programmes should therefore concentrate on trying to reach non-acceptors. The combination of mammographic screening and self-examination in a randomized trial could add to the existing evidence.

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Zusammenfassung Die Diskussion der beiden Arbeiten von Gästrin und Paccaud befasst sich mit den Unterschieden zwischen systematischem und unsystematischem screening: Nur ersteres hat in der Vergangenheit Effekte gezeigt. Nachuntersuchungen von Frauen, welche Screening akzeptiert haben, zeigen bessere Resultate als die randomisierten Studien; dies weist darauf hin, dass Frauen, welche in unsystematischem Screening nicht erfasst werden, ein höheres Risiko haben. Neue Programme sollten deswegen unbedingt darauf achten, auch diejenigen Frauen für Screening zu gewinnen, welche sonst nicht kommen. Die Kombination der zwei Ansätze: Mammographie Screening und Selbstuntersuchung der Brust in einer randomisierten Untersuchung könnte wichtige Hinweise zur Ergänzung der bestehenden Evidenz geben.

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Résumé La brève discussion des articles de Gästrin et Paccaud porte sur la diversité des résultats obtenus lors d'études de types différents. En introduisant le dépistage, le dépistage non-systématique fait place à un dépistage systématisé, qui s'est révélé être efficace. La comparaison entre des essais randomisés et des études de suivi chez des femmes acceptant le dépistage suggère que les femmes nonsoumises au dépistage ont un risque plus élevé. Les nouveaux programmes devraient porter leur attention sur la motivation de ces femmes à haut risque. La combinaison du dépistage par mammographie et de la palpation du sein par la femme elle-même pourrait, dans le cadre d'un essai clinique randomisé, apporter des éléments complémentaires renforçant l'evidence déjà existante.

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Paper presented at a symposium on The Public Health Perspective of Social and Preventive Medicine, in celebration of the 20th anniversary of the Department of Social and Preventive Medicine, University of Berne, 25 June 1992 in Berne.     

How protective is cervical cancer screening against cervical cancer mortality in developing countries? The Colombian case

Background  

Cervical cancer is one of the top causes of cancer morbidity and mortality in Colombia despite the existence of a national preventive program. Screening coverage with cervical cytology does not explain the lack of success of the program in reducing incidence and mortality rates by cervical cancer. To address this problem an ecological analysis, at department level, was carried out in Colombia to assess the relationship between cervical screening characteristics and cervical cancer mortality rates.