Quantitative lung scintigrams and lung function in the selection of patients for pneumonectomy

Abstract

A method for predicting postoperative respiratory function following lung resection has been used in 11 patients with both histologically proven bronchial carcinoma and chronic obstructive airways disease, in order to assess their fitness for surgical treatment. Quantitative ventilation and perfusion scintigrams were used to measure the amount of functioning tissue in each lung. These data were used in conjunction with spirometric measurements to calculate the likely functional effect of pneumonectomy. There was a high degree of correlation (r) between predicted and measured lung function for both FEV1 (r = 0.75, P less than 0.01) and FVC (r = 0.88, P less than 0.01). The postoperative FEV1 was within 150 ml of the predicted value in 45% of the patients. In the remaining patients the actual volumes were greater than predicted by 210-540 ml. For FVC the results were within 150 ml of predicted in 45% of patients and in the remainder actual volumes were greater by 160-650 ml. Both sets of calculations underestimated lung volumes by an average of 200 ml. The method is shown to be accurate, simple, non-invasive, and readily available and brings a degree of objectivity to an important decision that is often based mainly on clinical assessment.

ERS/ESTS clinical guidelines on fitness for radical therapy in lung cancer patients (surgery and chemo-radiotherapy)

“…The reported correlation between the actual and predicted post-operative FEV1 using quantitative ventilation/perfusion scintigraphy has been variable, with correlative figures quoted between r50.67 to r50.9 [62,63,91,93,[95][96][97][98][99]. Either ventilation scintigraphy [99] or perfusion scintigraphy [62,63,91] offer good prediction of post-operative lung function, but there seems to be no additional benefit in performing both [99].…”

“…Either ventilation scintigraphy [99] or perfusion scintigraphy [62,63,91] offer good prediction of post-operative lung function, but there seems to be no additional benefit in performing both [99]. The interpretation of the results, however, needs to take into account the fact that these techniques may underestimate the actual post-operative value [63,93,98].…”

Guidelines on the radical management of patients with lung cancer

“…[2−], 128 [2−], 129 [3], 130 [2−] There is also considerable uncertainty about the accuracy of quantitative perfusion to predict the postoperative FEV 1 in patients undergoing pneumonectomy 127. [2−], 129 [3], 131 [2−], 132 [3], 133 [3], 134 [3], 135 [3], 136 [2+] However, scintigraphy can be especially useful where an assessment has suggested that any further loss of lung function would be unacceptable if it is shown that no further (or minimal) lung function would be lost by operating. This applies where there may be compression of a pulmonary artery or marked emphysema in the lobe containing cancer.…”

“…[2+] It is important to bear in mind that scintigraphy results may underestimate actual postoperative values 127. [2−], 131 [2−], 134 [3] …”

Use of radionuclide scanning in the preoperative estimation of pulmonary function after pneumonectomy.

“…In the comparison of estimated and measured postoperative functional values previous authors6-9 23 have generally quoted only the correlation coefficient, which in this context is inadequate18 as it fails to give an estimate of the accuracy of the predicted value. In the present series of 28 patients we have plotted 95% confidence limits and confirmed that the method is sufficiently accurate to be of clinical value.…”