Physical agents

Chemical agents

Viruses

Although cancer is not contagious, some cancers are associated with viral infections. For example, the Epstein–Barr virus (EBV) causes a systemic infection that may precede Burkitt’s lymphoma, a malignant disease common in parts of Africa. Patients with chronic hepatitis B are more susceptible than others to liver cancer. The human papilloma virus (HPV), which may be sexually transmitted, is associated with cervical cancer, and the development of vaccines against some types of HPV has created opportunities to prevent some cases of cervical cancer (see p. 812).

Diet

Epidemiological studies that isolate diet as a causal factor in the development of cancer are extremely problematic to undertake. Nevertheless, dietary factors have been implicated as a major cause of the high incidence of cancer in the West. Countries where the average diet is high in fat and protein appear to have a high incidence of breast cancer, and low-fibre diets are thought to contribute to bowel cancer.

Health promotion programmes

Health promotion/education programmes have some measure of success. Several government publications have taken on ‘The Cancer Challenge’, with measures to promote a ‘pro-health’ culture (Department of Health 2000, Scottish Executive Health Department [SEHD] 2004). Projects have been developed to assist smokers to quit, particularly in areas with high levels of deprivation, prisons, the army and working men’s clubs. Political action has included a comprehensive ban on tobacco advertising, a smoking ban in public places and the workplace, the setting up of new stop-smoking clinics and a smokers’ helpline, nicotine replacement patches and bupropion available on prescription, as well as a major health education campaign in schools aimed at preventing youngsters from starting to smoke (Department of Health 2000, SEHD 2004).

Through working partnerships with the community and the food industry, strategies to promote healthy eating include a national ‘Five a Day’ programme, improving accessibility to affordable fresh fruit and vegetables, and advocating five portions of these daily (see Ch. 21) (Box 31.2).

Attitudes

Psychologists have developed a Health Belief Model (Strecher & Rosenstock 1997) to predict an individual’s preventive health behaviour and account for some of the factors which determine attitudes to health and illness. The Health Belief Model states that an individual feels vulnerable to a disease if they believe they are susceptible to developing it and believe the disease to be serious. Preventive action will be taken only after the individual has balanced the benefits of that action against its physical, psychological and financial costs (Smith 2005).

Despite being taught about the risks of smoking, teenage smokers may consider themselves to be young and healthy and therefore not ‘at risk’. Young people in general are motivated by short-term rather than long-term rewards. Smoking in some subcultures and families is associated with attributes such as maturity or rebelliousness, which the young person and their peer group may value. Later, the physical addiction to nicotine becomes a coping mechanism for life’s stresses and social deprivation. For such people, possible avoidance of lung cancer is not worth the cost of surrendering the immediate gratification and social status offered by smoking.

Clearly, consideration of the wider causes of individual behaviour would lead those involved in health promotion to an awareness of the social and political action necessary. The causes of social deprivation need to be considered alongside individual behaviour. Preventive services must be readily accessible, based on the expressed needs of the community and client-centred.

The concepts of health and ill health are open to wide interpretation. An essential aspect of communication is that everyone understands and attaches the same meaning to language used. If adherence to health care programmes is to be achieved, nurses need to understand an individual’s personal health beliefs and how information is interpreted.

Cancer screening difficulties

The development of an accurate and cost-effective method of screening at-risk sections of the population is problematic for several reasons. The test must have both a high degree of sensitivity, reducing the risk of false-negative results, and specificity, reducing the psychological trauma and expense of treating false-positive results.

It must be possible to identify an at-risk group; otherwise the cost of screening becomes prohibitive. Finally, and most problematically, it must be determined whether detecting the cancer type at an early stage will prolong life (Segnan et al 2004).

The general cancer screening programmes currently offered (in the UK) are:

Plus the Prostate Cancer Risk Management.

(See Useful websites NHS Cancer Screening Programmes.)

Breast cancer screening

Despite recent debates about the quality of over 40 years of trials, it is generally agreed that there is a clear benefit and reduction in mortality from breast cancer from screening women over the age of 50 years by mammography every 2 years (IARC 2002). In the UK mammography is routinely offered every 3 years to women aged between 50 and 70 years. However, the age range for routine invitation for screening is to be extended to include women aged 47 to 73. Accepted screening techniques include mammography and clinical breast examination, although Baxter (2001) has concluded that breast self-examination is of no benefit in routine screening. The value of screening women of 40 years or younger remains controversial, consequently professional clinical judgement and a woman’s choice should guide decision-making. The denser breast tissue of premenopausal women makes mammograms difficult to interpret in this age group. In future, genetic screening and new technologies such as digital mammography may be of benefit.

Cervical cancer screening

Cervical cancer is one of the most common female cancers in under-resourced economies. Since the introduction of the Papanicolaou (‘Pap’) smear test in the mid 1960s, there has been a steady decline in mortality rates in the UK. Women in the UK are first offered screening at age 25 years. This continues every 3 years until they reach the age of 49 years. Thereafter the test is offered at 5-year intervals until women reach the age of 64. Women aged 65 or over are only offered a smear test if they have not had a smear since they reached 50 or have recently had an abnormal smear. However, some GPs may offer early screening as part of their consultation with women regarding sexual health.

Uptake of the service by groups at highest risk, i.e. women over the age of 40, of lower socioeconomic status and in minority ethnic groups, could be better. Barriers to cervical screening include lack of sensitivity and trust in health professionals, possible feelings of guilt and embarrassment, judgemental attitudes, and a lack of privacy and supportive care in clinics (Fitch et al 1998). It is important for staff working in screening services to have well-developed interpersonal and communication skills to alleviate any fears or anxieties. In addition, clinic schedules should allow time to provide support.

Intervention strategies based on individual respect, health care provider relationships and inclusion of significant others may increase adherence to cancer screening guidelines (Steven et al 2004).

Colorectal cancer screening

The natural history of colon cancer with the relatively long time from biological onset to the development of cancer makes it a good candidate for screening. A national bowel screening programme based on faecal occult blood (FOB), using a home screening kit, was rolled out in 2006 (England) and 2007 (Scotland). The service became available throughout the UK in 2009.

Screening is routinely offered every two years to people aged 60–69 years (in England) and 50–74 years (in Scotland). However, people aged over 70 years in England can request a screening kit (NHS Cancer Screening Programme 2009a). People with an unclear result will have the FOB test repeated. Where an abnormal result occurs the person is offered an appointment with a specialist nurse to discuss colonoscopy (see Ch. 4). Campaigns by Colon Cancer Concern have been initiated to promote a greater awareness of the early warning signs of colon cancer (see Ch. 4).

Screening options for other cancers

Screening programmes for the cancers below are being reviewed, including:

Primary diagnosis

It is very common for patients to be aware that they have cancer before they are told formally of their diagnosis. This awareness derives from their experience of symptoms, tests and, in some cases, surgery and from the non-verbal communication of staff or relatives. How to inform patients in full of their diagnosis, and when this should be done are ongoing issues of ethical debate (Box 31.5).

Box 31.6 provides an opportunity for you to reflect on patient experiences of being given a diagnosis of cancer.

Even if they suspect their diagnosis, patients often cling to hope or use denial as a coping mechanism. These are the early emotional reactions experienced by people facing any actual or potential life crisis or loss, as described by Kübler-Ross in her seminal text (1973).

Disease recurrence

The discovery that the disease has recurred after a symptom-free period may provoke further psychological distress, as the patient realises there is no hope of cure. The period of waiting for test results, whether at initial diagnosis or at recurrence, can cause anxiety to both the patient and their family.

Psychological support

The nurse has an important role providing both practical information prior to and following each test, and emotional support. It is important to know why each test is being performed and what it will entail for the patient. Findings from research suggest that a substantial proportion of the lay public do not understand phrases used in cancer consultations. One study found that only 52% understood that the phrase ‘the tumour is progressing’ was not good news and less than a third understood what was meant by ‘seedlings’ (Chapman et al 2003). The nurse, acting as patient advocate, should ensure they are present when doctors explains test results so they are able to offer additional support and revisit this information again with the patient if necessary. The patient may have fears they wish to express and an opportunity to discuss these openly is important. The nurse is well placed do this.