Lung cancer


Fitness for Radical Therapy

Virtually all lung cancer sufferers have cardiovascular, respiratory and cerebro-vascular co-morbidity on the basis of their age, smoking and other occupational exposure. Particular attention needs to be paid to these factors when taking a history as all treatments have significant side-effects and leave the patient with a degree of debilitation. As surgery is the most radical of treatments fitness for surgery usually implies ability to undergo other radical therapies. However, even the usual surgical criteria may not be adequate to predict which patients can withstand multi-modality therapy.

The most useful test is that of exercise tolerance with the ability to walk a mile on flat ground or climb six flights of stairs without prolonged rest usually indicating fitness for lung resection. The forced expiratory volume in one second (FEV1) has been used as a useful guide to respiratory fitness for resection with a figure of 40% of the normal value indicating the ability to survive lobectomy without being left post-operatively as a “respiratory cripple”. For pneumonectomy an FEV1 of 60% is usually required. These indices can be further refined by using the transfer factor (an estimation of the diffusion capacity of the lungs by the single breath carbon monoxide washout method) and quantitated ventilation and perfusion lung scans to determine the predicted postoperative diffusion capacity (ppoDCO) which has a reasonable correlation with operative morbidity and postoperative respiratory handicap. “Borderline” patients or those with ischaemic heart disease may require confirmation of their exercise capacity on cardiopulmonary treadmill.

Compromise operations such as “sleeve” lobectomy, anatomic segmental resection, thoracoscopic resection or wedge resection may be possible if the degree of fitness is less than the above criteria. Those with localised tumours which can be treated without compromising large lung volumes or other vital structures like the heart may be suitable for radical radiotherapy though it is frequently the case that those who are unfit even for compromise surgery are unfit for radical radiotherapy. Similarly the currently active chemotherapy regimes require a WHO performance status of 0 or 1 and are contra-indicated in those with significant myocardial dysfunction ruling out many lung cancer patients. Patients who are not physiologically fit enough to undergo the required radical therapy may need to be considered for palliative therapies.