Lung cancer



Surgery remains, for the most part, the only cure for lung cancer. Though responses are seen following chemotherapy in NSCLC and good remission is common in small cell, cures are the exception. Similarly, radical radiotherapy is possible in only a small percentage of patients and when surgery is an option the results are superior to radiotherapy.

The aim of surgery is to resect the primary tumour with clear lateral and bronchial resection margins, the peribronchial lymphatic drainage of the tumour and the hilar lymph nodes. Mediastinal lymph node dissection performed at the time of lung resection provides vital staging and prognostic information which will determine the need for further therapies and may in itself contribute to local tumour control or cure.

Lobectomy is the most commonly performed operation for lung cancer, fulfilling the above criteria for complete oncological resection. Bilobectomy is the term for removing the middle lobe of the right lung in conjunction with either the upper or lower lobe. When the tumour crosses a major fissure involving all lobes of a lung, encroaches close to a main bronchus, either on the mucosal surface or with extrinsic compression by lymph nodes, or involves a main pulmonary artery, pneumonectomy, the removal of a whole lung, is necessary. This operation has a substantially higher mortality and incidence of long-term debility and should only be resorted to when tumour clearance cannot be obtained by a lung preserving procedure.

Lung resection is major surgery requiring not only particular surgical skill but specialist anaesthesia and post-operative care. Ideal operative conditions require maintaining the patient’s respiration on the contralateral lung while the affected lung is deflated for surgery. Cardiac instability is a frequent consequence. Post-operatively the patient spends 24 to 48 hours in a high dependency nursing unit and will speed a further week to 10 days in hospital depending on the severity of complications or the persistence of an air leak from the operated lung. Because of co-morbidity major complications occur in 30% of patients undergoing lung cancer surgery and the quoted peri-operative mortality is 3% for lobectomy and 8-10% for pneumonectomy.

Following lung resection it is uncommon for patients to return to full-time employment though some younger patients can return to desk work at 6 weeks if no adjuvant therapy is required. Intercostal neuralgia is a common consequence of thoracotomy requiring analgesic medication for 12 to 18 months post-operatively. Thereafter it rends to be of “nuisance value” only but some may need intercostal nerve block for persistent pain. Most patients will have decreased breathing capacity and will therefore not reach the levels of physical work they were capable of prior to surgery. However, where substantial atelectatic lung has been removed breathing can actually improve as the source of a major shunt has been removed.

When adjuvant therapy is indicated it can usually be commenced 3 to 6 weeks after surgery allowing time for wounds to heal and for the patient to pass the postoperative catabolic phase. There is at present no agreement on the indications or effects of post-operative radiotherapy or chemotherapy. It is common to irradiate areas where macroscopic tumour has been left at the time of surgery or where the surgeon feels he has not been able to achieve satisfactory margins. There is no evidence that irradiating a bronchial stump which has only microscopic evidence of residual disease has any effect on survival though it may reduce local recurrence (MRC postopeative radiotherapy trial). Similarly, postoperative radiation to the mediastinum when microscopic deposits have been found in mediastinal nodes decreases local recurrence but may also have a small but relevant survival benefit. As most life-threatening recurrence is outside the chest cavity only a systemic therapy can be expected to prolong life. There is evidence that Cisplatin based chemotherapy regimes have a small improvement in survival following surgery.

Routinely most surgeons will follow-up patients for 5 years following resection after which the risk of recurrence is low and the incidence of new primary tumours is similar to the general population as long as the patient has stopped smoking. Second metachronous primary tumours of the upper aero-digestive tract are, however, a major cause of death in long term survivors following lung resection. Primary care physicians need to be warned of this risk.