Primary care has an important role to play in the early diagnosis of lung cancer as well as providing follow up and palliative care, as Dr David Bellamy explains
Lung cancer is the most common cancer in men and the second most common cancer, after breast cancer, in women.1 In 2002, the disease caused nearly 29 000 deaths in England and Wales,1 and approximately 4000 in Scotland.2
Over the past 20 years there has been a small decline in the incidence of lung cancer in men but an increase in cases in women, reflecting changing patterns in smoking habits. Lung cancer is uncommon below the age of 40 years, but incidence rapidly increases with age, the most common age at presentation being 70-74 years.3
Survival rates for lung cancer are poor and do not appear to have changed greatly over the past 30 years. Only 21% of patients are alive after 1 year, and at 5 years a mere 5.5% are still alive.4 Sobering statistics show that the UK survival figures are 5 percentage points lower than the European average and 7-10 points lower than the average for the USA.5
There is thus considerable room for improvement. Much of the UK’s poor relative performance is attributed to delays in diagnosis; patients are often slow to present to their GP, there may be delays in referral to a respiratory specialist, and further delays waiting for hospital tests to be performed before the patient can begin appropriate treatment.
Lung cancer management is complicated by the fact that there are different treatments determined by the histological cell type of the cancer.
There are two main types: small cell lung cancer (SCLC), which accounts for 20% of cases, and non-small cell cancer (NSCLC), which constitutes the remaining 80%.6
The non-small cell group includes squamous cell carcinoma (35%), adenocarcinoma (27%) and large cell carcinomas (10%).6 In clinical practice, however, as many as one third of patients have no histological confirmation of cell type. Many of these have advanced metastatic disease at the time of diagnosis, and palliative care is the only suitable treatment.
Guidelines for lung cancer
NICE commissioned the National Collaborating Centre for Acute Care (NCC-AC) to produce a guideline on the diagnosis and treatment of lung cancer. This coincided with the review of SIGN 23, published in 1998, on the management of lung cancer.To avoid duplication of effort, therefore, the NCC-AC and SIGN collaborated in some aspects of guideline development, although each body developed its own clinical questions and recommendations. Both guidelines were launched in February 2005.7,8
Risk factors for lung cancer
Smoking is estimated to account for up to 90% of cases of lung cancer.6 The relative risk of an individual who smokes 20 cigarettes per day is 20 times greater than a lifetime non-smoker.6 Women who smoke are more likely to develop lung cancer than men.6 Stopping smoking before middle age cuts the risk of lung cancer by almost 90%.9
There is increasing evidence that environmental tobacco smoke could cause several hundred cases per year.10 Non-smokers who live with smokers have an increased risk of lung cancer of 24%.
Other risk factors include occupational exposure to asbestos and other carcinogens such as arsenic, cadmium and beryllium, and also environmental exposure to radon, a radioactive gas that comes from the natural decay of uranium that is found in most soils.
It is recognised that there are often delays between patients developing symptoms and reporting them to a GP; one survey found delays of between 3 weeks and 3 months.11
The symptoms and signs of lung cancer can be difficult for the GP to distinguish from other diseases such as COPD, asthma and chest infections. There is a considerable overlap of symptoms and no truly specific symptom pattern that predicts lung cancer can be identified (Box 1, below).
|Box 1: Frequency of initial symptoms and signs in lung cancer 12|
|Symptoms and signs||Range of frequency (%)|
|8 — 75
0 — 68
3 — 60
20 — 49
6 — 35
6 — 25
0 — 20
0 — 20
0 — 10
0 — 4
0 — 2
0 — 2
Whereas haemoptysis in a smoker over 40 years will set alarm bells ringing and prompt referral for a chest X-ray, less specific symptoms such as a persistent dry cough may not initially trigger such a response. When the patient presents with symptoms of metastatic disease, the GP may not immediately consider a diagnosis of lung cancer. The NICE guideline suggests that GPs should have a greater index of suspicion for lung cancer and, if appropriate, refer patients for a chest X-ray sooner.
A key recommendation for primary care concerns when to refer for urgent chest X-ray (Box 2, below).
|Box 2: Referral for urgent X-ray|
Urgent referral (within 2 weeks) should be offered for patients who present with:
Any of the following unexplained or persistent symptoms or signs that persist for more than 3 weeks:
Chest X-ray findings are abnormal in approximately 90% of symptomatic patients. However, a normal chest X-ray does not exclude a diagnosis of lung cancer. If the GP has suspicions of lung cancer, even if the chest X-ray is normal the patient should be referred urgently (within 2 weeks) to a respiratory physician who is a member of a multidisciplinary lung cancer team.
An urgent referral may need to be made before a chest X-ray result is available in circumstances such as persistent haemoptysis, superior vena cava obstruction or stridor, and emergency referral should be considered for patients with the latter two conditions.
If cancer is suspected on chest X-ray and the patient does not have advanced metastatic disease, the next investigation to be performed is a computed tomography (CT) scan. This should be performed before bronchoscopy or biopsy.
If the lesion in the lung is central, a fibreoptic bronchoscopy with biopsy is recommended. If the lesion is peripheral, percutaneous transthoracic needle biopsy is recommended.
Biopsy of a convenient metastatic site should be performed if this is easier than biopsy of a primary site.
NICE strongly recommends a new imaging test,18F-deoxyglucose positron emission tomography (FDG-PET), to help stage tumours and, often, to avoid unnecessary surgery.
FDG is a glucose analogue with positron emitting fluorine. Most malignant tumours have a higher glucose metabolism and thus take up more FDG than surrounding tissues, enabling this test to identify primary tumours and secondary deposits generally more effectively than any other.
Sadly, there are very few PET scanners in the UK – about five in all – largely because of the high initial costs and the running costs. The Department of Health has undertaken to make these scanners more readily available over the next 5 years.
If a chest X-ray or CT scan suggests lung cancer, patients should be referred urgently to a member of the lung cancer multidisciplinary team, usually a chest physician.
Small cell tumours
Small cell tumours are usually treated with 4-6 cycles of multi-drug platinum-based chemotherapy with the possibility of added radiotherapy in limited stage disease.
Small cell cancer tumours are the most rapidly growing and this type of cancer has the worst prognosis.
Non-small cell tumours
Staging of the disease and the patient’s overall fitness and exercise ability will determine the type of treatment chosen:
- Surgery: limited disease is best treated by surgery which offers the only chance of cure. Surgery is suitable for only about 10% of patients
- Radical radiotherapy
- A combination of radiotherapy and chemotherapy.
Palliative care alone may be appropriate for patients with advanced disease of any cell type.
Lung cancer should be managed by a multidisciplinary team consisting of hospital-based doctors, nurses and physiotherapists as well as the GP and practice staff, particularly community nurses.
The GP will usually see the patient at regular intervals, assess symptoms and changes, provide support for psychological and social problems and liaise closely with the hospital-based team members.
It is vital to involve the patient and family at all stages and to make decisions jointly with them about the type of treatment and overall support and care.
As the cancer progresses, patients may experience a wide range of symptoms, such as dyspnoea, cough, haemoptysis, bone pain, fatigue and weight loss as well as symptoms caused by distant metastases.
Palliative care is, again, best provided by a multidisciplinary team which will include specialist palliative care nurses and doctors, the primary care team and members of the hospital cancer multidisciplinary team.
The principles of care are based on:
- Providing relief from pain and other distressing symptoms
- Integrating the psychological and spiritual aspects of patient care
- Offering support to help patients live as actively as possible until death, and helping the family to cope during the patient’s illness and in their bereavement.
These principles should be applied early in the course of the illness in conjunction with other therapies to prolong life, and include investigations aimed at better understanding and management of distressing clinical complications.
Lung cancer is a common condition that requires a better understanding of early symptoms on the part of the public. When patients present to a GP there should be increased awareness of the possibility of lung cancer, with early referral for a chest X-ray if appropriate.
GPs and primary care teams are essential in the follow up and palliative care of patients following diagnosis.
Lung cancer: the diagnosis and treatment of lung cancer. NICE Clinical Guideline 24 can be downloaded from the NICE website: www.nice.org.uk.
Management of patients with lung cancer, SIGN 80, can be downloaded from the SIGN website: www.sign.ac.uk.
- Office for National Statistics. Mortality statistics cause. Review of the Registrar General on deaths by cause, sex and age, in England and Wales, 2002. London: Office for National Statistics, 2003.
- ISD Scotland. Information and Statistics. Health & Care. Cancer. Information. Lung cancer and mesothelioma. www.isdscotland.org/cancer_ information
- Quinn M, Babb P, Brock A et al. Cancer trends in England and Wales 1950-1999. Studies on medical and population subjects No. 66. London: The Stationery Office, 2001.
- Office for National Statistics. Cancer survival, England 1993-2000. London: Office for National Statistics, 2001.
- Welsh Cancer Intelligence & Surveillance Unit. Cancer Survival in Wales, 1989-1998. Cardiff: Welsh Cancer Intelligence & Surveillance Unit, 2003.
- Detterbeck FC, Rivera MP, Socinski MA, Rosenman JG. Diagnosis and treatment of lung cancer: An evidence-based guide for the practicing clinician. Philadelphia:W.B.Saunders Company, 2001.
- National Institute for Clinical Excellence. Lung cancer: the diagnosis and treatment of lung cancer. NICE Clinical Guideline 24. London: NICE, 2005.
- Scottish Intercollegiate Guidelines Network. Management of patients with lung cancer – a national clinical guideline. SIGN 80. Edinburgh: SIGN, 2005.
- Peto R, Darby S, Deo H, Silcocks P et al. Smoking, smoking cessation, and lung cancer in the UK since 1950: combination of national statistics with two case-control studies. Br Med J 2000; 321: 323-9.
- Hackshaw AK,Law MR,Wald NJ.The accumulated evidence on lung cancer and environmental tobacco smoke. Br Med J 1997; 315: 980-9.
- Krishnasamy M,Wilkie E. Lung cancer; patients’, families and professionals perceptions of health care need. A national needs assessment study. London: Macmillan Practice Development Unit, 1999.
- Beckles MA, Spiro SG, Colice GL, Rudd RM. Initial evaluation of the patient with lung cancer. Symptoms, signs, laboratory tests, and paraneoplastic syndromes. Chest 2003; 123(Suppl 1): 97S-104S.