Investigation of correlation between quantitative parameters derived from dual?energy CT and the differentiation degree of laryngeal and hypopharyngeal squamous cell carcinoma / 中华放射学杂志

ABSTRACT

Objective To investigate the correlation between quantitative parameters derived from iodine overlay images and the monochromatic images of dual‐energy CT and the differentiation degree of laryngeal and hypopharyngeal squamous cell carcinoma(LHSCC). Methods Retrospective analysis of clinical and imaging data of eighty patients with different differentiation degree of LHSCC who underwent dual‐energy CT enhanced scan in the arterial and venous phase from March 2016 to January 2017 (20, 42 and 18 patients with well, moderately and poorly differentiation, respectively) was performed.Among them, twenty‐eight cases were stage T1, twenty‐four cases were stage T2, twenty cases were stage T3 and eight cases were stage T4. All patients were not treated with radiotherapy and chemotherapy before operation. Iodine overlay images and the monochromatic images of arterial and venous phases were acquired from Syngo MultiModality Workplace dual‐energy post‐processing software of Siemens, respectively. The mean iodine concentration (IC), standardized iodine concentration (SIC), and the slope of spectral curve(λ) of different differentiation degrees of LHSCC were calculated and compared. The correlation between quantitative parameters of LHSCC and its differentiation degree was performed by Spearman rank sum test. One‐way analysis of variance was used to compare the quantitative parameters of different differentiation degree of LHSCC. Receiver operating characteristic (ROC) curve was used for analyzing diagnostic efficiency. Results The IC, SIC, and λ in the arterial phase, and IC in the venous phase correlated positively with differentiation degree in LHSCC (r=0.258, 0.350, 0.262 and 0.275, respectively; P<0.05) in this group. The IC, SIC, and λ of poorly differentiated LHSCC in the arterial phase [(3.13 ± 0.54) mg/ml, (0.38±0.10), (5.40±0.92)] were higher than those of well differentiated LHSCC [(2.38±1.02) mg/ml, (0.25± 0.09) and (4.19 ± 1.18); t=2.73, 3.36 and 2.75 respectively; P<0.05] and moderately differentiated LHSCC [(2.56±0.85) mg/ml, (0.28±0.16) and (4.56±1.41); t=2.38, 3.06 and 2.21, P<0.05]. IC of poorly differentiated LHSCC in the venous phase [(2.59 ± 0.62) mg/ml] was significantly higher than that of well differentiated LHSCC [(1.96±0.56) mg/ml,t=2.45,P<0.05] and moderately differentiated [(2.02±0.93) mg/ml,t=2.56,P<0.05] LHSCC. There was no significant difference in the SIC and λ between different differentiation degrees of LHSCC (P>0.05) in the venous phase. The standardized iodine concentration in the arterial phase was the best in distinguishing poorly and moderately differentiated LHSCC, and poorly and well differentiated LHSCC with the area under the receiver operating curve 0.77 and 0.81, respectively, the sensitivity 88.2% and 70.0%, respectively, and the specificity 69.0% and 70.0%, respectively. Conclusions Quantitative parameters derived from dual‐energy CT might be useful in the evaluation of different differentiated degrees of LHSCC. In addition, the standardized iodine concentration of LHSCC in the arterial phase was the best in the estimation of different differentiated degrees of LHSCC.