HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS		QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

This Article Figures Only Full Text Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Citation Map Services Email this article to a friend Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by Revel, M.-P. Articles by Frija, G. Search for Related Content PubMed PubMed Citation Articles by Revel, M.-P. Articles by Frija, G. Social Bookmarking                      What's this?

Software Volumetric Evaluation of Doubling Times for Differentiating Benign Versus Malignant Pulmonary Nodules

¹ Département de Radiologie, Assistance Publique des Hôpitaux de Paris, 20 rue Leblanc, Paris, F-75015 France.
² Université Paris-Descartes, Faculté de Médecine, Paris, F-75015 France.
³ Département de Radiologie, Hôpital Européen Georges Pompidou, Paris, F-75015 France.
⁴ Centre d'Investigations Cliniques, Hôpital Européen George Pompidou, Paris, F-75015 France.
⁵ Unité de Recherché Clinique, Hôpital Européen George Pompidou, Paris, F-75015 France.

OBJECTIVE. The purpose of our study was to evaluate the reliability of software-calculated doubling times for discerning malignant versus benign nodules.

MATERIALS AND METHODS. CT lung analysis volumetric software was used to retrospectively calculate the doubling times of 63 solid noncalcified nodules by comparing nodule volumes on baseline and follow-up CT scans obtained a median of 3.7 months apart. A final diagnosis based on validated criteria was available for all 63 nodules. All CT examinations were performed with 1.25-mm-thick slices on a four-detector unit. Taking 500 days as the upper value for malignancies, we evaluated whether the software-calculated doubling times could be used to distinguish malignant from benign solid nodules. We also examined whether the relative volume variation of benign nodules correlated with initial nodule size, interscan interval, or differences in contrast administration or exposure parameters between baseline and follow-up CT.

RESULTS. There were 52 benign and 11 malignant nodules. Benign nodules had a median doubling time of 947 days and a mean relative volume variation of -4.4% (range, -50% to 38%). Malignant nodules had a median doubling time of 117 days and a mean relative volume variation of 102% (22-462%). The sensitivity, specificity, and negative and positive predictive values of the volumetric software for diagnosing malignancy were 91% (95% confidence interval [CI], 0.59-1.00), 90% (95% CI, 0.79-0.97), 98% (95% CI, 0.89-1.00), and 67% (95% CI, 0.38-0.88), respectively. No correlation was found between the relative volume variation of benign nodules and their initial size, the interscan interval, or differences in contrast administration or exposure parameters between the two CT examinations.

CONCLUSION. Software-calculated pulmonary nodule doubling times of more than 500 days have a 98% negative predictive value for the diagnosis of solid malignant pulmonary nodules. This method may be useful for diagnosing malignant pulmonary nodules on follow-up CT.

Keywords: chest • comparative studies • computer applications—3D • CT • lung • lung cancer • MDCT • oncologic imaging

CiteULike    Complore    Connotea    Del.icio.us    Digg    Reddit    Technorati    What's this?

This article has been cited by other articles:

				C. Beigelman-Aubry, P. Raffy, W. Yang, R. A. Castellino, and P. A. Grenier Computer-Aided Detection of Solid Lung Nodules on Follow-Up MDCT Screening: Evaluation of Detection, Tracking, and Reading Time Am. J. Roentgenol., October 1, 2007; 189(4): 948 - 955. [Abstract] [Full Text] [PDF]