Article: Oncology for GPs: Lung Cancer
- Prevention
- Early detection: Referral
- Diagnosis:Tissue Diagnosis, Classification & staging
- Management: Small cell cancer, Non-small cell cancer, Mesothelioma, Advanced disease
- Case 1: Phillip
- Case 2: Christine
- In Practice
- Don't miss
The GP's role begins with patient education about lung cancer prevention, early detection and prompt and appropriate referral. The GP also provides support through the phases of specialist treatment and has an important part to play in the management of patients with advanced disease, including the in-home palliative care of the dying patient.
Lung cancer is the most common cause of cancer death in Australia. While it used to be identified as a male-dominated disease, this is changing with changes in smoking patterns. Both tobacco use and lung cancer incidence are increasing in Australian women aged 25-44 and, in one state at least, now exceed levels seen in men of the same age. The incidence of mesothelioma (other than cases related to asbestos exposure) is also increasing.
Prevention
Prevention is the only answer. Lung cancer continues to kill, despite modern therapies. GP health promotion targeting smoking should be unrelenting and multifaceted. Advice, literature, encouragement and support should be offered to all young people in an attempt to prevent them developing the smoking habit. Smokers should also be targeted.Those who are receptive and hoping to quit should be given encouragement. For those who are quitting, acupuncture, hypnotherapy and nicotine patches can all be helpful while they are going through nicotine withdrawal. The most important thing to offer the patient during this difficult time is support.
Lung cancer sufferers undergoing radical surgery or radiotherapy should also be encouraged to give up smoking, as this reduces the likelihood of cardiovascular complications.
Early Detection
Early detection, particularly while the patient is asymptomatic, increases the chance of finding a malignancy confined to the lung. Most lung cancers presenting with the classic symptoms of chronic cough and haemoptysis are advanced at the time of diagnosis.While screening might be useful in detecting individual cases, unfortunately no proposed program has been shown to be cost effective.
Suggestions made have included annually x-raying smokers aged over 50, and offering six-monthly chest x-rays to all ex-smokers of more than 20 pack-years. A high index of suspicion maintained by the GP continues to be the best method of early detection.
Clearly , while the use of chest x-rays to screen asymptomatic people for lung cancer is not currently recommended ,abnormalities detected on the chest x-rays done for other reasons must not be over looked . On the other hand, when symptomatic patients are being investigated, normal chest x-rays should not be regarded as having excluded pathology.
Referral
Chest physicians and surgeons are both involved in the early work-up and collaborate closely. Either is suitable as a first point of referral from the GP, and either is likely to involve the other, as necessary .Diagnosis
Tissue Diagnosis
Most areas within the chest can now be accessed, and biopsied, using fibre-optic scopes (for example, bronchoscopy, and mediastinoscopy).Needle or core biopsy can be useful in pre-treatment planning, but is not the investigation of choice. The needle can miss the tumour, and false positives occasionally occur. Open biopsy via thoracotomy is more reliable.
Classification and staging
A simplified, but practical, classification of lung cancers divides them into three types:- small cell
- non-small cell
- mesothelioma
Management
Small cell cancer
Chemotherapy is the treatment of choice for small cell cancer of the lung. In some cases of very early limited small cell cancer, the tumour is removed surgically prior to chemotherapy. The addition of consolidation thoracic radiotherapy to the treatment of limited-stage 'responders' has been shown to lead to a small increase in survival and a reduction in the incidence of local recurrence.Combination chemotherapy works better than any single agent. Combinations which contain platinum are more successful than those which do not. GP's whose patients are undergoing chemotherapy should be aware of significant potential complications, particularly those necessitating urgent action (for example, neutropaenic sepsis).
With treatment, median survival is 15 months for limited-stage disease and nine months for extensive-stage disease. Survival rates for patients treated for limited-stage disease are about 40% at two years and 10% at three years . Long-term survival is rare.
Without treatment, the condition deteriorates rapidly and the patient dies within a few weeks.
Non-small cell cancer
Non-small cell cancers are treated with surgery, radiotherapy or a combination of the two.Surgical resection is the treatment of choice, with resectability dependent on tumour stage and lung and heart health.
Contraindications to extensive resection of lung include vital capacity less than 40% of predicted, ischaemic heart disease (particularly infarction in the past six months) and significant arrhythmias. Primaries that are extensive or have spread beyond the lung are not resectable.
Small tumours that have not spread (T1 N0 M0) are associated with a survival rate of 70% five years after resection.
As atrial fibrillation develops in about 30% of patients aged over 50 who undergo thoracotomy, prophylactic digoxin is often used for the 4-6 weeks following surgery.
Radiotherapy is used alone for cancers unsuitable for resection and as adjuvant therapy in cases where resection is inadequate or nodes are involved. Radiotherapy is now site-specific and side effects are minimal. Some patients undergoing lung irradiation for large primaries develop pneumonitis. This presents with fever and dyspnoea, and usually settles rapidly with high-dose oral steroids.
Mesothelioma
Mesothelioma is difficult to diagnose and, in most cases, has a very poor prognosis. Surgery is the treatment of choice in the rare cases in which cure is a possibility.Advanced Disease
When lung cancer progresses, both metastatic disease and local extension can lead to symptoms. Locally extensive disease can result in Horner's syndrome, vocal cord paralysis, phrenic nerve damage and obstruction of any structure in the chest, most frequently the superior vena cava.While metastatic disease can arise anywhere, the most common sites are the other lung , liver , brain and bone. Specific sites should only be investigated in response to the development of symptoms or signs.
Palliative radiotherapy is used in the treatment of pain, obstructions and haemoptysis, and to achieve control of locally extensive disease.
In advanced disease ,the GP must be alert to presenting symptoms and refer appropriately for palliative oncology.
The neurosurgeon's skills, for example, can provide temporary but much appreciated relief from the effect of a solitary cerebral metastasis. The pain of bony involvement is greatly relieved by radiotherapy. The skills of the medical oncologist can also be helpful.
The GP should not be afraid to use these modalities. All these specialists can be very sensitive to the need for balance between life time and life quality. Patients can be denied months of improved quality of life if denied a palliative procedure.
The in-home palliative care of the dying patient is the privileged responsibility of the GP. Intermittent oxygen from an air separator and high doses of narcotics should be used for symptom control, as required. The pain relief achieved by morphine achieves better respiratory effort . Steroids, purgatives, tricyclic antidepressants and other drugs may also be needed.
The GP must also provide support, information and continuity to the patient and family.
In Practice
- Most lung cancers presenting with the classic symptoms of chronic cough and haemoptysis are advanced at the time diagnosis.
- Survival rates for treated limited-stage small cell cancer are about 40% at two years and 10% at three years.
- Localised non-small cell tumours less than 3 cm in diameter have a 70% survival rate five years after resection.
- Mesothelioma has a poor prognosis.
Case 1: Phillip
Phillip was a fifty year old newsagent who had been smoking since his teenage years. He exercised regularly at the local gym and maintained a healthy weight. He blamed his lobar pneumonia on his heavy workload and the cool air in the mornings when he was delivering newspapers. His fever and pain settled within 10 days of antibiotics and he felt well.His follow-up x-ray two weeks later had a persistent opacity close to the hilum in the right middle lobe. We discussed the implications. A subsequent CT scan revealed a 5 cm mass but no significant (>1cm)mediastinal nodes. He understood the importance of stopping smoking and agreed to do so then and there. We talked about the future.
I made Phillip an appointment with a cardiothoracic surgeon and sent with him his chest x-rays and CT scans, an FBC, LFTs, spirometry and a detailed history.
The surgeon referred Phillip to a physician for bronchoscopy and biospy, which led to a diagnosis of non-small cell cancer. Taking into account the size of the tumour and the CT findings, this was staged as T2 N0 M0.
With the diagnosis established, education of the patient is largely the responsibility of the GP. We discussed his treatment and prognosis and I gave him a copy of the Queensland Cancer Fund publication 'Understanding Cancer of the Lung'.
Thoracotomy revealed a more extensive tumour than predicted. He underwent right total pneumonectomy with removal of nodes for biopsy. One of the six nodes was directly invaded. Phillip recovered well and was discharged on prophylactic digoxin with a request for me to watch his levels and maintain him on a therapeutic dose.
Because of his mediastinal node involvement, he was referred to a radiation oncologist and completed six weeks of treatment with minimal side effects. He complained of heartburn due to radiation oesophagitis and achieved reasonable control with simple antacids. Two months after diagnosis he was back running the newsagency.
Two years later he bought his daughter in with a bout of gastroenteritis. She was nearing final exams. When I asked how he was he complained he was terribly out of condition, becoming short of breath after walking only short distances. He had had to employ someone to carry and lift for him. I suggested he make an appointment to see me.
There were nodes in the right supraclavicular area and his voice was hoarse. Chest x-ray showed fluffy opacities throughout the left lung. Gently, I brought him around to the realisation of what he was facing. The chest physician confirmed my diagnosis of metastatic disease and local recurrence.
Treatment of Phillip's disease at this stage involved only rationalisation of his lifestyle. Once the shop was sold, he was able to enjoy some months with his family. He played nine holes of golf twice a week with the help of a buggy, and was able to watch the boys ' football matches and attend his daughter's graduation.
Just before Christmas he limped into my office complaining of severe pain in his left hip. A bone scan revealed secondaries in his left hip, skull and ribs. Palliative radiotherapy provided very good pain relief for three months until he sustained a pathological fracture .The symptoms then became overwhelming.
Phillip was treated at home with the help of his family and palliative care nurses. They were given my home phone number and encouraged to use it freely. Dyspnoea and pain were relieved using an air separator to provide oxygen and a syringe-driver to deliver subcutaneous morphine. Purgatives, tricyclic antidepressants and dexamethasone were added when they became necessary.
On the night he died, his family and I shared a tear and a coffee at the kitchen table, as we had often done over the previous weeks. To my horror, son Danny and daughter Gail lit up cigarettes!
Improvements arising through advances in our understanding of oncogenesis and refinements in the treatment of lung cancer are far less significant than the benefit that would result from eliminating smoking.
Non-small cell lung cancer, presenting as cough and haemoptysis
Christine's cancer was an incidental finding on a chest x-ray taken prior to her hysterectomy. Bronchoscopy and mediastinoscopy revealed a small cell carcinoma without nodal spread. She was given six cycles of etoposide and carboplatin, with three-week intervals between treatments.
During chemotherapy she presented with fever and myalgia, and complaining of 'flu' . An urgent WCC revealed neutropaenia, and a diagnosis of neutropaenic sepsis was made. She was admitted to hospital for IV antibiotics and recovered fully from the infection.
As CT and bronchoscopy found no trace of cancer after her chemotherapy, she went on to radiotherapy. Two years after diagnosis, she is alive but her prognosis remains guarded.
Don't miss ...
- Any opportunity to target smoking as a disease risk factor
- Any opportunity to detect lung cancer early
- Uncontrolled symptoms in patients with advanced disease
CT reveals the extent of the primary and assists in the staging of the tumour (T2 NO MO)
Portable film taken after right total pneumonectomy.
This article is reproduced with the kind permission of Dr Margaret King and Medical Observer.Medical Observer, Continuing Medical Education Program, pp 4-6, 11 Oct 96
The author wishes to thank her specialist mentors Dr Al Mutazz Diqer (cardiothoracic surgeon), Dr Peter jeal (radioation oncologist) and Dr Vasta Varman (pathologist).
Page currency, Latest update: 14 February, 2006