Evaluation of locoregional invasiveness of small-sized non-small cell lung cancers by enhanced dual-energy computed tomography

Abstract

BackgroundTo investigate the correlation between iodine-related attenuation of dual-energy computed tomography (DE-CT) and the histopathological invasiveness of surgically resected primary non-small cell lung cancers (NSCLCs) ≤ 3 cm in diameter.MethodsWe selected 63 consecutive NSCLC lesions from 60 patients (32 males, 28 females; age range, 39–85 years; mean age, 68 years). After injection of iodinated contrast media, arterial phases were scanned using 140-kVp and 80-kVp tube voltages. Three-dimensional iodine-related attenuation (3D-IRA) of primary tumors at the arterial phase was computed using “lung nodule” application software. The corrected 3D-IRA normalized to the patient’s body weight and contrast medium concentration was then calculated. Single-factor analysis of variance (ANOVA) was used for comparison among tumor differentiation grade groups. Univariate and multivariate logistic regression analysis was used for the correlation between locoregional invasive tumor and clinical factors.ResultsResected tumors were histopathologically classified into well-differentiated (G1; n = 24), moderately-differentiated (G2; n = 28), and poorly-differentiated (G3; n = 11) groups by degree of tumor differentiation. The mean ± standard deviation of the 3D-IRA was 56.1 ± 22.6 HU in G1 tumours, 48.5 ± 23.9 HU in G2 tumours, and 28.4 ± 15.8 HU in G3 tumours; significant differences were observed between groups by ANOVA. (p = 0.005). Univariate logistic analysis showed that the 3D-IRA and corrected 3D-IRAs were significantly correlated with locoregional invasive tumors (p = 0.002 and p < 0.001, respectively). Multivariate logistic analysis revealed that only the corrected 3D-IRA was significantly correlated with tumor invasiveness (p = 0.003), while gender, clinical size, and solid/subsolid type were not (p = 0.950, p = 0.057 and p = 0.456, respectively).ConclusionsThe 3D-IRA of small-sized NSCLCs was significantly associated with and invasiveness. Low 3D-IRA tumors tended to have greater invasiveness than high 3D-IRA tumors.

Diagnostic value of spectral reconstructions in detecting incidental skeletal muscle metastases in CT staging examinations

“…In CT, the assessment of the muscular system regarding metastatic lesions is severely hampered by different factors: the skeletal muscles constitute a large volume to investigate and usually show high attenuation so that iso- and moderately hyperattenuating metastases may get obscured. In the past, dual energy CT (DECT)-derived reconstructions highlighting the iodine signal have been shown to increase contrast and improve depiction of malignant lesions such as liver metastases, hepatocellular carcinoma, pancreatic or lung tumors [24–29]. This can be achieved using iodine-specific maps or lower-energetic virtual monochromatic images which result in a higher x-ray absorption of iodine as the energy level is moved closer to its absorption maximum, the k-edge (33.2 keV) [30].…”

Comparative study of dual energy CT iodine imaging and standardized concentrations before and after chemoradiotherapy for esophageal cancer

“…These can effectively inhibit the proliferation of tumor blood vessels and reduce the blood supply in the cancer area, then reduce the uptake of iodine by tumor cells. Vascular IC can reflect the efficacy of CMT drugs within the tissue [ 16 , 19 – 26 ].…”

Translation of Quantitative Imaging Biomarkers into Clinical Chest CT

“…In contrast, the results of a study of 60 patients with 63 non-small cell lung cancers showed that volumetric iodine attenuation measurements in the primary lesion that were obtained with dual-energy CT were actually significantly lower in poorly differentiated tumors, compared with those in well-differentiated tumors (60). Iodine attenuation was also negatively correlated with local-regional invasiveness in the findings from this study (60). As a biomarker, iodine attenuation has also been investigated in the differentiation of metastatic and nonmetastatic mediastinal lymph nodes in non-small cell lung cancer.…”

“…In patients with established lung cancer, iodine quantification with dual-energy CT showed a moderate positive correlation (r = 0.51) with metabolic activity (ie, fluorine 18 fluorodeoxyglucose uptake) in both the primary lesion and in metastatic lymph nodes (59). In contrast, the results of a study of 60 patients with 63 non-small cell lung cancers showed that volumetric iodine attenuation measurements in the primary lesion that were obtained with dual-energy CT were actually significantly lower in poorly differentiated tumors, compared with those in well-differentiated tumors (60). Iodine attenuation was also negatively correlated with local-regional invasiveness in the findings from this study (60).…”