Surgery chapters
Lung cancer, lung surgery and mediastinal masses
Fitness for lung resection, lung cancer types, presentation, staging and surgery (lobectomy, pneumonectomy, segmentectomy), other lung conditions that need surgery, and masses of the anterior, middle and posterior mediastinum.
- Fitness for lung resection rests on three risks: death (Thoracoscore), heart events and breathlessness (predicted postoperative FEV1/TLCO from a segment count).
- Lung cancer is small cell (about 20%, rarely operable) or non-small cell; surgery with curative intent suits T1–3, N0–1 disease, and lobectomy is the operation of choice, after staging with CT, PET-CT and EBUS/mediastinoscopy.
- The anterior mediastinum holds thymoma (commonest), teratoma/germ cell tumour, lymphoma and thyroid; the posterior mediastinum holds neurogenic tumours.
On this page
Overview
Lung cancer is the commonest cause of cancer death. Only about 20–30% of cases are resectable at presentation, so the thoracic surgeon's roles are diagnosis, staging, curative resection in selected patients, and palliation.
This chapter covers fitness for lung surgery, lung cancer (types, presentation, staging and operations), other lung problems that need surgery, and mediastinal masses.
Fitness for lung resection
British Thoracic Society advice uses a tripartite risk assessment:
| Risk | How it is assessed |
|---|---|
| Death | Thoracoscore (age, sex, ASA grade, performance status, dyspnoea score, urgency, extent of surgery, malignancy, comorbidity) |
| Heart event | History, examination, ECG, cardiac risk scoring; cardiology review if active heart disease. Avoid surgery within 30 days of an MI |
| Breathlessness afterwards | Spirometry (FEV1), transfer factor (TLCO/DLCO), segment count, exercise tests |
Predicted postoperative lung function
There are 19 bronchopulmonary segments. Assume each works equally:
Predicted postoperative (ppo) FEV1 = preoperative FEV1 × (19 − segments removed) ÷ 19
Preoperative FEV1 1.8 L (70% predicted); planned right upper lobectomy (3 segments).
ppoFEV1 = 1.8 × (19 − 3) ÷ 19 = 1.8 × 16 ÷ 19 = 1.52 L
ppoFEV1% = 70 × 16 ÷ 19 = about 59% predicted → well above the often-quoted 40% threshold → acceptable breathlessness risk.
- A ppoFEV1 or ppoTLCO of about 40% is a commonly quoted cut-off, but patients at higher risk may still choose surgery if they accept the risk.
- If borderline: shuttle walk (cut-off about 400 m) or cardiopulmonary exercise testing (peak oxygen uptake cut-off about 15 mL/kg/min).
- Patients who cannot have surgery may be offered radical (curative) radiotherapy.
Lung cancer
Risk factors
- Smoking causes 85–95%. Risk relates to pack-years (packs of 20 per day × years smoked).
- Others: asbestos (multiplies the smoking risk), radon, radioactive ore mining, chromium, nickel, arsenic, air pollution, pulmonary fibrosis.
Types
| Type | Key features |
|---|---|
| Small cell (oat cell) | About 20%. Neuroendocrine, central, strongly smoking-related, spreads early. Very chemosensitive but rarely cured. SIADH, ectopic ACTH, Lambert–Eaton. Surgery rarely (only very limited disease) |
| Adenocarcinoma | Now the commonest NSCLC. Peripheral; commoner in women and non-smokers; EGFR and ALK mutations (targeted drugs) |
| Squamous cell | Central; cavitates; PTHrP → hypercalcaemia |
| Large cell | Undifferentiated NSCLC |
| Lepidic adenocarcinoma (formerly bronchioloalveolar) | Grows along alveolar walls; ground-glass shadow on CT |
| Carcinoid | Low-grade neuroendocrine tumour of major bronchi; younger patients; recurrent pneumonia, haemoptysis; vascular; carcinoid syndrome only with metastases. Resection (often sleeve) gives excellent results |
Small cell to non-small cell ratio is about 1:4.
Clinical features
| Mechanism | Feature |
|---|---|
| Local | Cough (new or changed), haemoptysis (in under half), breathlessness, chest pain, monophonic wheeze, recurrent pneumonia |
| Chest wall invasion | Severe localised pain |
| Apical (Pancoast/superior sulcus) tumour | Brachial plexus (C8–T1): arm pain, small hand muscle wasting; Horner's syndrome (sympathetic chain) |
| Mediastinal invasion | Hoarseness (left recurrent laryngeal nerve), dysphagia, SVC obstruction, phrenic palsy (raised hemidiaphragm), pericardial effusion |
| Pleura | Effusion (bloody = direct invasion) – usually means inoperable |
| Non-metastatic | Clubbing, hypertrophic pulmonary osteoarthropathy, Lambert–Eaton, endocrine syndromes |
| Metastases | Liver, adrenal, bone, brain, skin |
UK NICE advice: urgent chest X-ray for haemoptysis, or for cough, chest/shoulder pain, breathlessness, weight loss, clubbing, hoarseness or neck nodes that are unexplained or present over 3 weeks. Urgent referral for persistent haemoptysis in a smoker over 40, SVC obstruction or stridor.
Investigations and staging
| Test | Role |
|---|---|
| Chest X-ray | Detects most tumours, collapse, effusion, raised hemidiaphragm; can be normal |
| CT chest and upper abdomen (with contrast) | First investigation: T stage, nodes, liver and adrenal metastases. Nodes over 2 cm are likely involved; under 1 cm short axis unlikely |
| PET-CT (FDG) | Hidden nodal and distant spread; false positives with infection/inflammation |
| Sputum cytology | High false-negative rate |
| Flexible bronchoscopy | Central tumours: biopsy, brushings, washings |
| EBUS-TBNA | Needle sampling of mediastinal and hilar nodes through the airway – no incision |
| EUS-FNA | Through the oesophagus for other mediastinal nodes |
| CT-guided biopsy | Peripheral lesions; pneumothorax is common (about 30%) but rarely needs a drain |
| Cervical mediastinoscopy | Under GA through a small incision above the suprasternal notch; samples paratracheal and subcarinal nodes |
| Anterior mediastinotomy | Through the 2nd intercostal space; reaches para-aortic/subaortic nodes (left upper lobe tumours) |
| VATS | Biopsy of hard-to-reach nodes or tumour; assesses operability |
Mediastinoscopy cannot reach the subaortic (aortopulmonary window) nodes; these need anterior mediastinotomy or VATS.
TNM in brief (8th edition)
| T | Size or extent |
|---|---|
| T1 | ≤ 3 cm, not in the main bronchus |
| T2 | > 3 to 5 cm, or main bronchus involved (not carina), visceral pleura invaded, collapse to the hilum |
| T3 | > 5 to 7 cm, or chest wall, phrenic nerve, parietal pericardium, separate nodule in the same lobe |
| T4 | > 7 cm, or mediastinum, heart, great vessels, trachea, carina, oesophagus, vertebra, recurrent laryngeal nerve, diaphragm, nodule in another ipsilateral lobe |
| N | Nodes |
|---|---|
| N1 | Ipsilateral hilar/peribronchial (stations 10–14) |
| N2 | Ipsilateral mediastinal or subcarinal (stations 2–9) |
| N3 | Contralateral mediastinal/hilar, or scalene/supraclavicular |
| M | Spread |
|---|---|
| M1a | Nodule in the opposite lung, pleural or pericardial nodules or malignant effusion |
| M1b | Single extrathoracic metastasis |
| M1c | Multiple extrathoracic metastases |
"3–5–7" – the size steps between T1, T2, T3 and T4.
Who gets surgery?
- NSCLC stage T1–3, N0–1, M0 in a fit patient → resection with curative intent.
- Not usually operable: N2 bulky/N3 nodes, M1 disease, malignant pleural effusion, tumour fixed to aorta, heart or oesophagus.
- Small cell → chemotherapy ± radiotherapy; surgery only in very limited disease.
A pleural effusion in lung cancer is staged M1a, not T4 – and generally puts the tumour beyond cure.
Lung operations
| Operation | Use | Key facts |
|---|---|---|
| Lobectomy (VATS or open) | Treatment of choice for early NSCLC | 30-day mortality about 2–3%; stay about 5–7 days; air leak usually settles in days |
| Segmentectomy / wedge resection | Small tumours (T1a–b N0) with borderline fitness; metastases | Lung-sparing |
| Pneumonectomy | Central tumours involving the main bronchus or crossing the fissure | Mortality about 5–8%; no suction on the space drain |
| Sleeve (bronchoplastic) resection | Central tumours, especially carcinoid | Saves lung, avoids pneumonectomy |
All curative operations include hilar and mediastinal lymph node sampling or dissection.
Lobectomy (open or VATS) is the operation of choice for early NSCLC; segmentectomy or wedge resection is kept for small tumours in patients with poor reserve, and pneumonectomy only when needed for clear margins because its mortality is higher.
Access
- Posterolateral thoracotomy (patient lateral, double-lumen tube for one-lung ventilation; incision below the scapular tip; usually the 5th/6th space) – standard open route to lung, oesophagus, descending aorta and posterior mediastinum.
- VATS through 1–3 ports: less pain, shorter stay.
- Median sternotomy: anterior mediastinum and bilateral anterior lung metastases.
Complications of lung resection
- Bleeding.
- Sputum retention, collapse and pneumonia (many are smokers).
- Atrial fibrillation.
- Persistent air leak.
- Bronchopleural fistula (stump breakdown, mainly after pneumonectomy): the patient coughs up large amounts of fluid from the space; the fluid level on X-ray falls. Sit the patient up and lie on the operated side to protect the other lung; drain (underwater seal, no suction); specialist repair.
- Post-thoracotomy pain – prevent with epidural or paravertebral block, PCA and regular paracetamol; avoid trapping intercostal nerves on closure.
After pneumonectomy, the empty space slowly fills with fluid and the air–fluid level rises. A sudden drop in the level with productive cough means bronchopleural fistula.
Lung metastases (metastasectomy)
Consider resection when the primary is controlled, there is no disease outside the lung, all nodules can be removed with lung-sparing (wedge) surgery and lung function allows. Best results with germ cell tumours; bowel cancer and sarcoma metastases are common indications.
Other lung conditions needing surgery
| Condition | Surgical role |
|---|---|
| Benign nodules/tumours | Most benign nodules are granulomas (TB). Commonest benign tumour: hamartoma. A nodule stable for over 2 years or calcified is likely benign |
| Bronchiectasis | Resect only if localised and causing bleeding or recurrent infection |
| Lung abscess | Most settle with antibiotics and postural drainage; surgery rarely |
| Tuberculosis | Possible cancer, resistant TB cavity/abscess, aspergilloma, life-threatening haemoptysis – always with anti-TB drugs |
| Pulmonary sequestration | Non-functioning lung with a systemic arterial supply from the aorta; intralobar type gets infected; resection |
| Bullae, cysts | Resection (e.g. VATS) if large or complicated; hydatid cysts in endemic areas such as Pakistan |
The mediastinum
The central chest compartment between the two pleural sacs, from the thoracic inlet to the diaphragm and from the sternum to the spine. It is divided at the sternal angle (T4/5) into superior and inferior parts; the inferior part into anterior, middle and posterior.
Mediastinal masses by compartment
| Compartment | Usual masses | Surgical approach |
|---|---|---|
| Anterior / anterosuperior | Thymoma, teratoma (germ cell), lymphoma, retrosternal thyroid, lipoma, parathyroid | Median sternotomy (or cervical/VATS) |
| Middle | Lymph nodes (lymphoma, metastases, TB, sarcoid), bronchogenic and pericardial cysts | Thoracotomy or VATS |
| Posterior | Neurogenic tumours, foregut (oesophageal duplication) cysts | Thoracotomy or VATS |
Anterior mediastinum = the four Ts: Thymoma, Teratoma, Thyroid, "Terrible" lymphoma.
Thymoma
- Commonest mediastinal tumour (about 25%).
- Associated with myasthenia gravis; also red cell aplasia and hypogammaglobulinaemia.
- Behaviour ranges from benign to invasive; the only reliable sign of malignancy is capsular invasion (Masaoka staging: I encapsulated → II capsular invasion → III invades nearby organs → IVA pleural/pericardial spread → IVB distant).
- Treatment: complete thymectomy, usually via median sternotomy. Thymectomy can help myasthenia even without a thymoma (transcervical or VATS approach possible).
Whether a thymoma behaves as malignant is judged by invasion of its capsule (and beyond), not by how the cells look under the microscope.
Germ cell tumours
- The anterior mediastinum is the commonest site outside the gonads; about 13% of mediastinal masses; young adults.
- About 75% are benign (mature teratoma/dermoid cyst) – excise.
- Raised AFP or β-hCG suggests malignancy (seminoma or non-seminoma) → chemotherapy first; resect any residual mass once markers normalise.
Lymphoma
A common cause of an anterior mass; may cause SVC obstruction or stridor. Treatment is chemotherapy; surgery only to get tissue for diagnosis.
Retrosternal goitre
Extension of a thyroid mass into the superior/anterior mediastinum. Remove if it compresses the airway (stridor); most come out through a neck incision, occasionally sternotomy.
Neurogenic tumours (posterior)
- Commonest posterior mediastinal mass, in the paravertebral gutter.
- Children: neuroblastoma, ganglioneuroma. Adults: schwannoma, neurofibroma (usually benign). Phaeochromocytoma can arise from the sympathetic chain.
- Often found incidentally; may widen an intervertebral foramen. Excise (thoracotomy or VATS).
Cysts
Bronchogenic, pericardial (often at the right cardiophrenic angle), thymic and foregut cysts. Excise if symptomatic or the diagnosis is unclear.
Enlarged mediastinal lymph nodes from metastatic cancer are common and can mimic a primary mediastinal tumour; mediastinoscopy is for diagnosis, not cure.
Expect: tripartite risk assessment and how to calculate predicted postoperative FEV1 from 19 segments; smoking and pack-years; features of each lung cancer type (squamous cavitation and hypercalcaemia, small cell SIADH and early spread, adenocarcinoma peripheral in non-smokers, carcinoid in a major bronchus); Pancoast tumour and Horner's syndrome; CT as the first test, PET-CT, EBUS and mediastinoscopy (and which nodes need mediastinotomy); T size steps 3–5–7 cm and N1/N2/N3; effusion as M1a; lobectomy as the operation of choice and its mortality versus pneumonectomy; bronchopleural fistula; commonest benign lung tumour; thymoma and myasthenia; the four anterior mediastinal Ts; germ cell markers; and neurogenic tumours in the posterior mediastinum.
Quick revision
- Fitness: Thoracoscore + cardiac risk + ppoFEV1/TLCO (19 segments; about 40% cut-off).
- Smoking causes 85–95%; adenocarcinoma commonest NSCLC; small cell about 20%, rarely operable.
- CT chest/upper abdomen first; PET-CT for spread; EBUS or mediastinoscopy for nodes.
- Curative surgery for T1–3 N0–1 M0 NSCLC; lobectomy (2–3% mortality) is first choice.
- Pneumonectomy 5–8%; no suction; falling fluid level + productive cough = bronchopleural fistula.
- Hamartoma = commonest benign lung tumour.
- Anterior: thymoma, teratoma, thyroid, lymphoma; posterior: neurogenic.
- Thymoma: myasthenia, capsular invasion = malignant, thymectomy via sternotomy.
Written by The House Job from standard references (Bailey & Love; Kumar and Clark's Clinical Medicine).
FAQ
Which lung cancers can be cured by surgery?
Non-small cell cancers that are confined to the lung and nearby hilar nodes (T1–3, N0–1, no metastases) in a patient fit enough for resection.
Why is small cell lung cancer rarely operated on?
It spreads to nodes and distant organs very early, so by diagnosis it is almost always beyond local surgery and is treated with chemotherapy and radiotherapy.
What is the difference between mediastinoscopy and mediastinotomy?
Mediastinoscopy goes in through a small cut above the sternal notch to sample nodes beside the trachea and under the carina; mediastinotomy goes through the second intercostal space to reach the subaortic and para-aortic nodes.
Which mediastinal tumour is linked with myasthenia gravis?
Thymoma; removing the thymus can also improve myasthenia even when no tumour is present.