VOL: 102, ISSUE: 16, PAGE NO: 17
Alison Leary, MSc, BA, BSc, RN, is Macmillan lecturer in oncology, University College London Hospital NHS Foundation TrustLung cancer remains the UK's biggest cancer killer, with over 33,000 people dying of lung cancer each year (Cancer Research UK, 2005). Despite improved survival rates in other cancers such as breast cancer, lung cancer survival rates in the UK have changed little in the last 30 years, with an average five-year survival of just 7%.
Lung cancer remains the UK's biggest cancer killer, with over 33,000 people dying of lung cancer each year (Cancer Research UK, 2005). Despite improved survival rates in other cancers such as breast cancer, lung cancer survival rates in the UK have changed little in the last 30 years, with an average five-year survival of just 7%.
Non-small cell lung cancer (NSCLC) is the most common type, with most patients presenting at an advanced stage (Silvestri and Rivera, 2005), which makes curative attempts through surgery an option for few. Advanced NSCLC is usually locally advanced disease in the chest or a primary tumour of the lung or bronchus with metastatic spread.
Current treatment options for advanced lung cancer focus on chemotherapy, radiotherapy or best supportive care, which consists of symptom control and psychological, social and spiritual care.
Poor five-year survival in advanced lung cancer reflects the technical difficulty in developing drugs to treat this disease but there is also evidence that other socio-political factors are involved. The Public Accounts Committee has recently issued a report confirming that there is still an identified link between variations in the incidence of lung cancer and levels of socio-economic deprivation (Public Accounts Committee, 2006).
The link between lung cancer and smoking tobacco established in the 1950s (Doll and Hill, 1954) and subsequent health promotion campaigns have influenced the public perception of lung cancer as a disease of smokers. In a recent survey the UK Lung Cancer Coalition found that 40% of the population considered lung cancer to be self-inflicted, despite the fact that one in eight lung cancer patients have never been smokers (UK Lung Cancer Coalition, 2005). The established epidemiological link with tobacco use means that lung cancer patients often experience feelings of stigmatisation and guilt (Chapple et al, 2004).
Poor five-year survival may also be due to a lack of investment in lung cancer research. Currently 4% of UK cancer research funding goes towards lung cancer research (The Roy Castle Foundation, 2006).
Treating advanced lung cancer
Even though five-year survival rates in lung cancer have shown little improvement, an increase in one-year survival has been noted. In England and Wales one-year survival in men with advanced NSCLC has risen from 15% in the 1970s to 25% in 2000-2001 (Coleman et al, 2004). A possible reason for this is the introduction of new treatment options.
The last 10 years have seen the development of new chemotherapy and biological agents in addition to novel ways of utilising radiotherapy and supportive care. Despite the historical lack of investment in lung cancer research, many collaborative groups have come together to answer therapeutic questions.
Platinum-based chemotherapy remains the basis of first-line treatment in advanced NSCLC. A combination of cytotoxic chemotherapy agents such as gemcitabine, which kills cells undergoing DNA synthesis (S-phase of the cell cycle), and platinum chemotherapy agents such as carboplatin, are administered intravenously on 21-day cycles. It is not possible to target chemotherapy to affect only cancer cells and so toxicity from these drugs can have adverse effects such as myelosuppression.
A recent study by the London Lung Cancer Group found the combination of gemcitabine and carboplatin to be well tolerated by patients (Rudd et al, 2005) but the administration of IV chemotherapy regimens is labour intensive for both the nurse and the patient, requiring visits to hospital for administration and monitoring. While these third-generation regimes are recommended (NICE, 2005), the study by Rudd et al confirmed an increased survival of only 2.4 months - a finding that is comparable with other studies.
As chemotherapeutic agents continue to offer only small survival advantages and cannot be offered to patients with co-morbidities such as poor renal function, clinicians working in lung cancer are now turning to therapies that directly target cancer at a molecular level. The majority of these new agents target epidermal growth factor receptors (EGFR). These proteins, found on the surface of many cells, bind to growth factors needed for cell growth. In many cancer cells, including NSCLC, EGFR is over-expressed or constantly signals for cell growth. Blocking EGFR would result in slowing or stopping tumour growth, potentially without causing the side-effects currently experienced by patients receiving systemic chemotherapy agents.
Some EGFR inhibitors are already in clinical use. One such treatment, erlotinib, selectively inhibits the tyrosine kinase activity of the EGFR (Fig 1) and has demonstrated anti-tumour activity in patients who have progressed through conventional chemotherapy (Silvestri and Rivera, 2005).
These new biological agents also have the added advantage of being offered in oral tablet form. This means that patients receiving such biological agents would not need to use chemotherapy nursing services and, providing that appropriate specialist support was available, would need fewer visits to hospital, helping them to achieve a better quality of life. Such biological agents also offer avenues of treatment to patients who are unable to tolerate chemotherapy regimens because of co-morbidity or poor performance status.
The link between smoking and lung cancer is an established one and there is no doubt that smoking cessation would be the most effective measure in decreasing lung cancer incidence. However, in comparison with other cancers the pharmacological treatment of patients with advanced NSCLC still has a long way to go. By countering negative social attitudes and being aware of new treatments, nursing is in a strong position to advocate for this group of patients and their families.
This article has been double-blind peer-reviewed.
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