History
A 60-year-old female presents to her GP with a non-productive cough and weight loss over four months. She complains of generalized aches and pains and more recently she has become constipated. She is a current smoker with a 40 pack-year history, she is a social drinker with no other significant history.
Examination
On examination, her skirt is loose and held up by a belt. Her finger nails are clubbed.
She is not cyanosed. Her respiratory rate is 18 per minute and there is reduced air entry in the right upper zone of the chest. Abdominal examination is unremarkable and she is apyrexial and normotensive.
Investigations
Blood tests reveal hypercalcaemia and an elevated parathyroid hormone level. The GP sends her for a chest x-ray and the image is shown in Figure 26.1.
Figure 26.1
Case 26: Woman with cough and weight loss 123
QUESTIONS
1. What does the chest x-ray demonstrate?
2. What is the most likely diagnosis?
3. What is the differential diagnosis?
4. What would you do next as the GP?
5. What do the biochemical tests suggest?
6. How would you ensure that a patient is prepared for a computed tomography (CT)-guided lung biopsy?
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ANSwERS
1. In the right upper lobe, there is a radiopaque mass measuring 4 cm in diameter.
There is an air–fluid level seen behind the medial aspect of the right clavicle.
Appearances are consistent with a cavitating lung lesion.
2. The most likely cause in the context of this patient’s history is bronchogenic carci-noma, and squamous cell carcinoma (SCC) is the most likely type of lung cancer to cavitate.
3. Causes of cavitating lung lesions can be remembered by the mnemonic ‘CAVITY’.
Carcinoma, Cystic bronchiectasis, Autoimmune diseases, Vascular disease, Infections and Youth, i.e. congenital causes. Primary or secondary squamous cell carcinomas are the most common causes – remember head, neck and cervix as possible pri-mary sites. Tuberculosis, Staphylococcus aureus and Klebsiella also cause cavitation, although the patient would be systemically unwell.
4. Urgent respiratory referral is required. If malignancy is suspected, as it is in this case, the respiratory team will request a CT of the chest, abdomen and pelvis for staging purposes and the patient would need to be discussed in a multidisciplinary meeting to make an appropriate management plan.
5. The patient has hypercalcaemia secondary to ectopic secretion of parathyroid hor-mone from the SCC which is causing constipation and generalized aches and pains.
This is known as a paraneoplastic syndrome and is most often seen with SCC of the lung, genitourinary or gynaecological malignancies. Hypercalcaemia may also be related to bone metastases which should be considered and excluded (radionuclide bone scan).
6. Patient preparation includes sufficient explanation of the procedure, with informed, written consent and recent clotting factors with an international normalized ratio (INR) around 1.0. If the patient is on warfarin, it is prudent to discuss with the hae-matologists. Institutions will have their own protocols which should be checked. In certain cases, warfarin can be stopped temporarily and swapped for daily treatment dose low-molecular-weight heparin (LMWH) injections, omitted the day before the procedure. The INR is monitored until it is approximately 1.0 and the patient is able to have the lung biopsy. Post-biopsy, LMWH and warfarin are restarted until the INR is at a therapeutic level and the LMWH can be stopped. Risks of CT-guided lung biopsy include infection, bleeding and pneumothorax. A chest film 4 hours post-procedure should always be performed to ensure there is no latent pneumotho-rax (remember to review this, or arrange review and document your findings in the patient’s notes).
The patient was referred to the respiratory physicians and an axial image from the CT of the chest is shown in Figure 26.2. The patient was lying prone at the time of the scan with the head towards the reader. In the right upper lobe, adjacent to the vertebral body, there is a large soft tissue lesion which contains an air – fluid level (arrow A). This corresponds to the mass seen on the chest x-ray. Note vertebral
Case 26: Woman with cough and weight loss 125
body (arrow B), trachea (arrow C) and a left upper lobe bulla (arrow D). A lung biopsy confirmed squamous cell carcinoma.
Figure 26.2
Bronchogenic, or lung cancer, is subdivided into small cell lung cancer (SCLC) and non-small cell lung cancer (NSCLC). SCLC is associated with smoking, is usually located centrally within the lung, grows rapidly and metastasizes early.
NSCLC includes adenocarcinoma, SCC and undifferentiated large cell carcinoma.
Adenocarcinoma is most commonly seen in non-smokers and females, is peripher-ally located in the lung, grows slowly but may metastasize early. Bronchoalveolar carcinoma is a subtype of adenocarcinoma which may present as a nodule or a focus of consolidation on a chest film. It may develop within an area of scarred lung fibrosis secondary to tuberculosis, bronchiectasis or scleroderma. Persistent consolidation 6–8 weeks after antibiotic therapy should raise the suspicion of cancer and patients require further investigation. SCC is associated with cigarette smoking, may be located centrally or peripherally within the lung and has the slow-est growth rate of all the subtypes and is least likely to metastasize distantly. It is, however, the most likely type to cause chest wall invasion. Undifferentiated large cell carcinoma is associated with smoking, is usually large, centrally or peripherally located, grows rapidly and metastasizes early.
Histological confirmation of malignancy and the cell type in conjunction with a staging CT is essential for surgeons, radiotherapists and oncologists to make an appropriate management plan. Biopsy may be performed via bronchoscopy if the lesion is fairly central, or using CT guidance if it is more peripherally located. The TNM (tumour, nodes, metastasis) staging system is used to stage NSCLC and to decide on operability. A staging CT assesses the size of the primary tumour and
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the extent of invasion into local structures, the presence and size of ipsilateral and contralateral lymph nodes, and the presence of supraclavicular lymph nodes. Spread of cancer to the lymph nodes is suspected when the nodes are enlarged by CT criteria or are round rather than oval in morphology. Finally, metastases within the lungs or pleura, or distant metastases to bone, adrenal glands, brain, and liver, are checked for on the staging CT. TNM staging is revised regularly.
Risk factors for lung cancer include cigarette smoking, male gender, scarred lung fibrosis and exposure to asbestos, uranium and radon gas. Radon gas is a colour-less, radioactive gas which is produced by the radioactive decay of uranium in soil and rocks. High levels increase the risk of lung cancer, particularly in smokers and particularly high levels in the UK are found in Cornwall. A relevant occupational and social history is therefore necessary when presenting symptoms suggest bron-chogenic carcinoma.