Solitary Pulmonary Nodules: Part I. Morphologic Evaluation for Differentiation of Benign and Malignant Lesions

Abstract

The solitary pulmonary nodule is a common radiologic abnormality that is often detected incidentally. Although most solitary pulmonary nodules have benign causes, many represent stage I lung cancers and must be distinguished from benign nodules in an expeditious and cost-effective manner. Evaluation of specific morphologic features of a solitary pulmonary nodule with conventional imaging techniques can help differentiate benign from malignant nodules and obviate further costly assessment. Small size and smooth, well-defined margins are suggestive of but not diagnostic for benignity. Lobulated contour as well as an irregular or spiculated margin with distortion of adjacent vessels are typically associated with malignancy. There is considerable overlap in the internal characteristics (eg, attenuation, cavitation, wall thickness) of benign and malignant nodules. The presence of intranodular fat is a reliable indicator of a hamartoma. The presence and pattern of calcification can also help differentiate benign from malignant nodules. Computed tomography (CT) (particularly thin-section CT) is 10-20 times more sensitive than standard radiography and allows objective, quantitative assessment of calcification. Initial evaluation often results in nonspecific findings, in which case nodules are classified as indeterminate and require further evaluation to exclude malignancy. Growth rate assessment, Bayesian analysis, contrast material-enhanced CT, positron emission tomography, and transthoracic needle aspiration biopsy can be useful in this regard.

Prediction Models for Solitary Pulmonary Nodules Based on Curvelet Textural Features and Clinical Parameters

“…While some demographic parameters and morphological features taken into the data sets had similar results with the Mayo Clinic model and other research (Khan et al, 1991;Gurney, 1993;Erasmus et al, 2000;Alzubi et al, 2011), smoking history (i.e. whether the patient smoked or not) did not reflect a difference between malignant and benign nodules.…”

Integrated multislice CT and Tc–99m Sestamibi SPECT–CT evaluation of solitary pulmonary nodules

“…Negli ultimi anni si sta assistendo ad una profonda revisione del concetto di diagnosi precoce del cancro del polmone grazie agli incoraggianti risultati ottenuti con la tomografia computerizzata multistrato [8,14,15], ed a tecniche complementari di medicina nucleare. Un NPS è definito come una opacità rotondeggiante intraparenchimale moderatamente ben delimitata con diametro massimo inferiore a 3 cm [1]. Nella differenziazione tra lesioni benigne e maligne in TC sono stati individuati criteri qualitativi, basati sulla morfologia del nodulo e quantitativi, rappresentati dalla densità, caratteristiche di enhancement dopo somministrazione di MdC organoiodato e dalla velocità di crescita della lesione nei casi sottoposti a controllo.…”

“…A solitary pulmonary nodule is defined as a rounded intraparenchymal opacity that is moderately well delimited, with a maximum diameter less than 3 cm [1]. CT differentiation of benign and malignant lesions is based on qualitative (nodule morphology) and quantitative (density, postcontrast enhancement characteristics, and le- …”

“…A few nodules can be defined as probably benign (presence of fat or benign calcification) and not requiring further investigation; others are highly suspicious for malignancy (spiculated margins, malignant calcification, diameter >2 cm) and require immediate surgical excision or biopsy [1]. The majority of pulmonary nodules (70%), however, cannot be characterised with certainty, even after a CT scan.…”

Evaluation of detection rate of pulmonary nodules and the reasons may affect their visibility on chest radiograms

“…Çalışmamızda, bu oran yaklaşık %31 olarak hesaplanmıştır. Bu oran literatür ile uyumluluk göstermektedir (6)(7)(8) . Radyografik incelemeler PACS sisteminde bulunan dijital radyografi raporları üze-rinden yapıldı.…”