The correlation between metabolic parameters in (18)F-FDG PET-CT and solid and micropapillary histological subtypes in lung adenocarcinoma / 中华肿瘤杂志

Objective: Solid and micropapillary pattern are highly invasive histologic subtypes in lung adenocarcinoma and are associated with poor prognosis while the biopsy sample is not enough for the accurate histological diagnosis. This study aims to assess the correlation and predictive efficacy between metabolic parameters in (18)F-fluorodeoxy glucose positron emission tomography/computed tomography ((18)F-FDG PET-CT), including the maximum SUV (SUV(max)), metabolic tumor volume (MTV), total lesion glycolysis (TLG) and solid and micropapillary histological subtypes in lung adenocarcinoma. Methods: A total of 145 resected lung adenocarcinomas were included. The clinical data and preoperative (18)F-FDG PET-CT data were retrospectively analyzed. Mann-Whitney U test was used for the comparison of the metabolic parameters between solid and micropapillary subtype group and other subtypes group. Receiver operating characteristic (ROC) curve and areas under curve (AUC) were used for evaluating the prediction efficacy of metabolic parameters for solid or micropapillary patterns. Univariate and multivariate analyses were conducted to determine the prediction factors of the presence of solid or micropapillary subtypes. Results: Median SUV(max) and TLG in solid and papillary predominant subtypes group (15.07 and 34.98, respectively) were significantly higher than those in other subtypes predominant group (6.03 and 10.16, respectively, P<0.05). ROC curve revealed that SUV(max) and TLG had good efficacy for prediction of solid and micropapillary predominant subtypes [AUC=0.811(95% CI: 0.715~0.907) and 0.725(95% CI: 0.610~0.840), P<0.05]. Median SUV(max) and TLG in lung adenocarcinoma with the solid or micropapillary patterns (11.58 and 22.81, respectively) were significantly higher than those in tumors without solid and micropapillary patterns (4.27 and 6.33, respectively, P<0.05). ROC curve revealed that SUV(max) and TLG had good efficacy for predicting the presence of solid or micropapillary patterns [AUC=0.757(95% CI: 0.679~0.834) and 0.681(95% CI: 0.595~0.768), P<0.005]. Multivariate logistic analysis showed that the clinical stage (Stage Ⅲ-Ⅳ), SUV(max) ≥10.27 and TLG≥7.12 were the independent predictive factors of the presence of solid or micropapillary patterns (P<0.05). Conclusions: Preoperative SUV(max) and TLG of lung adenocarcinoma have good prediction efficacy for the presence of solid or micropapillary patterns, especially for the solid and micropapillary predominant subtypes and are independent factors of the presence of solid or micropapillary patterns.

The features of solitary pulmonary nodules of adenocarcinoma on 18F-FDG PET/CT / 中华核医学杂志

ObjectiveTo study the imaging characteristics of SPN of adenocarcinoma (ASPNs) on 18F-FDG PET/CT.MethodsThe morphological and metabolic features of 35 ASPNs on FDG PET/CT were retrospectively reviewed.SUVmax (SUV) was measured and ΔSUVmax was calculated according to ΔSUVmax =(SUVmax on delay imaging - SUVmax on early imaging)/SUVmax on early imaging × 100％.Statistical analysis was performed by software SPSS 11.5 using t-test,analysis of variance and Fisher exact test.Results( 1 ) Fifteen ASPNs (42.86％,15/35) presented as nodular pattern on FDG PET imaging,while 20 (57.14％,20/35) as lamellar,cloudy or ill-defined patterns.The SUVmax of these ASPNs followed a descending order of nodular,lamellar,cloudy and ill:defined on both early and delay imaging (F =30.696 and 24.758,both P＜0.001).(2)There were 54.29％ (19/35) ASPNs with SUVmax ≥2.5 and 45.71％ (16/35) ASPNs with SUVmax ＜2.5.(3) Of 35 ASPNs,24(68.57％ ) were solid nodules and 11(31.43％) were ground glass nodules with SUVmax =4.54 ±2.69 and 1.30±0.87,respectively (t =-5.234,P ＜O.001 ).(4) The SUVmax of ASPNs on delay FDG imaging (4.22 ±3.52) was significantly higher than that on early imaging (3.49 ±2.72) (t =-4.021,P ＜0.001 ).However,SUVmax was dependent on SUVmax on the early imaging:when SUVmax ≥2.5,ΔSUVmax was positive in 94.74％ (18/19) of ASPNs; while SUVmax ＜2.5,ΔSUVmax was positive in 56.25％ (9/16) of ASPNs (P =0.013).(5) Of 31 ASPNs with cell differentiation data,there were 10/17 well-differentiated ASPNs and 13/14 poorly-differentiated ASPNs with positive ΔSUVmax ( P =0.045 ).The average SUVmax of well-differentiated ASPNs was significantly lower than that of poorly-differentiated ASPNs ( 1.70 ± 1.51 vs 4.91 ± 2.69,t =- 3.951,P ＜ 0.001 ).Conclusions The morphological and metabolic features of ASPNs are diversified.It is common for ASPN to present with SUVmax ＜ 2.5.ΔSUVmax may be helpful for differentiating malignant from benign SPNs.