Evaluation of lobar lymph node metastasis in non-small cell lung carcinoma using modified total lesion glycolysis

Abstract

Background: Volumetric parameters based on 3-dimensional reconstruction have recently been introduced for cancer staging. We aimed to improve the ability to diagnose hilar lymph node metastasis in patients with non-small cell lung cancer. Methods: We evaluated 142 patients with non-small cell lung cancer who underwent right upper lobectomy and radical lymph node dissection. Metastatic involvement of right upper lobar lymph nodes was assessed using high-resolution computed tomography (HRCT) and 18F-2-floro-2-deoxyglucose-positron emission tomography/computed tomography (FDG-PET/CT). Results: On receiver operating characteristic (ROC) curve analysis, the area under the curves (AUC) for short axis, maximum of standardized uptake value (SUV max), total lesion glycolysis (TLG) and modified TLG (mTLG) were 0.79, 0.77, 0.76, and 0.87, respectively. The sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) of mTLG, using the optimal cut off value (2.45), for diagnosis of lobar lymph node metastasis were 71%, 88%, 44%, and 96%, respectively. Hilar asymmetric uptake (HAU) of FDG was larger in true-positive cases than in false-negative cases (P<0.01). Furthermore, the size of metastatic foci in the lymph node was smaller in false-negative cases (P=0.012). Conclusions: Modified TLG is a good parameter to diagnose metastatic right upper lobar lymph nodes. Micrometastasis in the lymph node is difficult to predict using the current diagnostic method. However, more careful evaluation is required in patients with symmetric FDG accumulation at hilar region because hilar lymph nodes respond to various causes such as benign pulmonary diseases.

Selection of Pathological N0 (pN0) in Clinical IA (cIA) Lung Adenocarcinoma by Imaging Findings of the Main Tumor

“…Some lymph node metastases, such as micrometastases, do not give an accurate metastasis evaluation no matter how closely the degree of swelling of the lymph nodes, area under an ROC curve; C/T: CD/T; CD: maximal consolidation diameter evaluated with lung window setting; T: total tumor diameter evaluated with lung window setting; LN: lymph node metastasis; ly: lymph vessel invasion; MD: maximal diameter evaluated with mediastinal window setting; pl: pleural invasion; ROC: receiver operating characteristic; SUVmax: maximum standardized uptake value; v: vascular invasion or the uptake of FDG into the lymph nodes, are examined. [17][18][19] We have reported that both the imaging findings (MD, solid components of tumor) of the tumor and CEA values are highly correlated with the degree of tumor invasiveness, which allows more accurate preoperative evaluation of lymph node metastasis in cIA. [5][6][7][8]20) CD is a rational tumor size measurement method that reflects the degree of adenocarcinoma, and was adopted in the 8th edition WHO classification.…”

“…Some lymph node metastases, such as micrometastases, do not give an accurate metastasis evaluation no matter how closely the degree of swelling of the lymph nodes, or the uptake of FDG into the lymph nodes, are examined. 17 – 19) We have reported that both the imaging findings (MD, solid components of tumor) of the tumor and CEA values are highly correlated with the degree of tumor invasiveness, which allows more accurate preoperative evaluation of lymph node metastasis in cIA. 5 – 8 , 20) CD is a rational tumor size measurement method that reflects the degree of adenocarcinoma, and was adopted in the 8th edition WHO classification.…”

Presurgical heterogeneity of lung 18FDG-PET uptake predicts acute exacerbation of interstitial lung disease following pulmonary resection in patients with smoke exposures

“…All patients underwent 18 FDG-PET prior to surgical resection. The generation and evaluation of 18 FDG-PET scans has been described in detail in previously published articles [19][20][21][22]. PET-CT images were acquired according to a standard imaging protocol using a dedicated PET/CT scanner (Biograph 40; SIEMENS Healthcare Japan Co., Japan).…”

“…Parameters such as total lung glycolysis (TLG), as well as maximum and mean 18 F-FDG uptake, were obtained by PET, whereas TLG was calculated as the product of mean 18 F-FDG uptake and metabolic tumour volume. The maximum and mean 18 F-FDG uptake and the metabolic tumour volume of NSCLC and ILD areas were calculated using a SIEMENS MMWP workstation, as previously reported [19][20][21][22]. A technical assistant blinded to the clinical data calculated these parameters.…”