Detection of primary and recurrent lung cancer by means of F-18 fluorodeoxyglucose positron emission tomography (FDG PET)

Abstract

Positron emission tomography (PET), with the glucose analog F-18 fluoro-deoxyglucose (FDG), takes advantage of the enhanced glucose uptake observed in neoplastic cells. We examined whether the detection of preferential FDG uptake with PET permits differentiation between benign and malignant focal pulmonary lesions in patients with suspected primary or recurrent lung cancer. Between November 1991 and September 1993, 100 patients with indeterminate focal pulmonary abnormalities including 16 patients who had previous lung resections for cancer were prospectively studied. Tissue diagnosis was obtained by transbronchial or percutaneous biopsy (n = 49) and open biopsy or resection (n = 35). Three patients underwent extended observation (> 2 years) alone. Excluded were 13 patients lacking firm pathologic diagnoses and less than 2-year follow-up. FDG activity in the lesion was expressed as a calculated standardized uptake ratio. Mean standardized uptake ratio (+/- standard deviation) was 6.6 (+/- 3.1) in 59 patients with cancer versus 2.0 (+/- 1.6) in 28 with benign disease (p = 0.0001; unpaired t test, two-sided). With a standardized uptake ratio > or = 2.5 used for detecting malignancy, sensitivity, specificity, and accuracy were 97% (57/59), 82% (23/28), and 92% (80/87), respectively. Notably, in patients evaluated for pulmonary abnormalities after lung resection for cancer, all chest recurrences were correctly identified. The exceptional sensitivity of FDG PET demonstrates that malignant pulmonary lesions preferentially accumulate FDG, which results in a standardized uptake ratio > or = 2.5. PET may be useful for distinguishing recurrent tumor from postoperative, or postradiation, changes. If performed in all patients before open biopsy, PET increases the diagnostic yield by reducing the number of patients who have benign lesions at operation. Moreover, by lowering expenditures for hospitalization and other diagnostic procedures, FDG PET may significantly reduce health care costs.

PET for the Evaluation of Solitary Pulmonary Nodules

“…These factors then determine how we should decide who could benefit from a PET study and once the test has been performed how the result could influence management. Given the excellent performance parameters that we identified-a likelihood ratio of 9.9 for a positive PET read as ''definitely malignant'' and a likelihood ratio of 0.03 for a negative PET read as ''definitely benign''-it is still unlikely that patients with either a very low (5%) or very high pretest probability (.80%) of a malignant solitary pulmonary nodule would benefit from this examination (2). In a cost-effectiveness analysis of 18 F-FDG PET in solitary pulmonary nodules, Gould et al reached similar conclusions and indicated that 18 F-FDG PET should be used selectively when pretest probability and CT findings are discordant or in patients COPYRIGHT ª 2009 by the Society of Nuclear Medicine, Inc.…”

“…The data presented in the article, however, also address an even more controversial clinical issue, namely: what is the visual or standardized uptake value (SUV) cutoff for classifying a solitary pulmonary nodule as benign? The traditional teaching, supported by numerous early, pivotal studies, including several by the authors of this paper, is that nodules with an SUV less than 2.5 or whose activity appears visually to be less than or equal to that of the mediastinal blood pool can be considered benign with enough confidence to avoid an immediate biopsy; these nodules can safely be followed with CT (2,3). Recently, several groups have published data contradicting this principle (4), including evidence that any visually perceptible uptake by a pulmonary nodule is associated with a significant chance of malignancy (5).…”

Oncological applications of positron emission tomography with fluorine-18 fluorodeoxyglucose

“…Knopp [124,125]. Others have also reported a high diagnostic accuracy of FDG PET in the detection of tumour recurrence [113,[126][127][128][129][130].…”

Imaging in lung cancer: positron emission tomography scan

“…FDG-PET has thus been studied extensively as a promising noninvasive imaging test to differentiate between benign and malignant nodules [27][28][29][30][31][32][33][34][35][36][37]. Based on 12 well-designed prospective studies, it can be concluded that FDG-PET has proven to be accurate in differentiating benign from malignant lesions as small as 1 cm [21].…”

“…Therefore, falsenegative findings can occur in lesions v1 cm [29,30,34,35,38], in tumours with low metabolic activity (e.g. carcinoid tumours [30,39]), or in bronchioloalveolar cell carcinoma [38,[40][41][42].…”