Objectives: The aim of this study was to investigate the clinical significance of the sum of the maximum standardized uptake value (sumSUV_max) on pretreatment positron emission tomography/computed tomography (¹⁸F-FDG-PET/CT) in newly diagnosed small-cell lung cancer (SCLC). Methods: We retrospectively analyzed 145 SCLC patients from March 2005 to June 2013 who underwent pretreatment ¹⁸F-FDG-PET/CT. The sumSUV_max was assessed in all malignant lesions up to a maximum of 5 lesions and a maximum of 2 lesions per organ according to RECIST 1.1. Results: A significant difference was found between the low and high sumSUV_max groups (low vs. high sumSUV_max, 91.5 vs. 77.3%; p = 0.018) in the response rate (RR) following frontline platinum-based chemotherapy. The group with low sumSUV_max showed significantly better overall survival (OS; p < 0.001) as well as better progression-free survival (PFS; p < 0.001) compared with the group with high sumSUV_max. Moreover, multivariate analysis revealed that a high sumSUV_max alone was an independent poor prognostic factor for OS (hazard ratio 2.676; 95% confidence interval, 1.674-4.277; p < 0.001). Conclusions: This study showed that the sumSUV_max adopted from RECIST 1.1 on pretreatment ¹⁸F-FDG PET/CT was significantly correlated with response to treatment, OS, and PFS in patients with SCLC.

(18)F-fluoride PET/CT is superior to WBBS or (18)F-FDG PET/CT in detecting osteosclerotic metastatic lesions. (18)F-fluoride PET/CT might be useful in evaluating osteosclerotic metastases in breast cancer patients.

Squamous cell carcinoma (SCC) and adenocarcinoma (AC) are the major histological types of non-small cell lung carcinoma (NSCLC). Although both SCCs and ACs have been characterized histologically and clinically, the precise mechanisms underlying their migration and invasion are not yet known. Here, we address the involvement in NSCLC of the p21-associated kinase1 (Pak1)/LIM kinase1 (LIMK1)/cofilin pathway, which recently has been reported to play a critical role in tumor migration and invasion. The Pak1/LIMK1/cofilin pathway was evaluated in tumors from SCC (n=35) and AC (n=35) patients and in SCC- and AC-type cell lines by western blotting, immunohistochemistry, and in vitro migration and invasion assays. The levels of phosphorylated Pak1, LIMK1, and cofilin in lung tumor tissues from SCC patients were increased as compared to normal tissues. In addition, immunohistochemistry showed greater expression of phosphorylated cofilin in SCC tissues. Expression of phosphorylated Pak1 and LIMK1 proteins was also significantly higher in SCC-type cells than in AC-type cells. Moreover, migration and invasion assays revealed that a higher percentage of SCC type cells exhibited migration and invasion compared to AC type cells. Migration was also decreased in LIMK1 knockdown SK-MES-1 cells. These findings suggest that the activation of the Pak1/LIMK1/cofilin pathway could preferentially contribute to greater tumor migration and invasion in SCC, relative to that in AC.

Purpose Gastric signet ring cell carcinoma (GSRC) is known to have low fluorodeoxyglucose (FDG) uptake. The aim of the study was to investigate the relation between FDG uptake and glucose transporter (GLUT)-1 expression and clinicopathologic parameters in cases of GSRC. Materials and Methods Forty patients (28 men, mean age 54±12 years) with histologically confirmed GSRC who underwent pre-operative [18 F]FDG PET/CT were enrolled. Maximum standardized uptake values (SUVmax) were compared with clinicopathologic parameters and GLUT-1 expression. Cases were divided based on GLUT-1 expression in tumor tissues into a membranous group (n=17) and a cytoplasmic group (n=23). Results Mean SUVmax was significantly higher in the membranous group than in the cytoplasmic group (6.06± 2.79 vs. 3.67±1.54, P=0.03). Gastric wall invasion, depth of invasion, extent of LN metastasis, overall stage, and tumor size were found to be related to SUVmax. On the other hand, age, sex, and the presence of distant metastasis were not related to SUVmax. Multivariate analysis revealed that membranous GLUT-1 expression and the extent of LN metastasis independently predicted high FDG uptake. Conclusions This study demonstrates that high FDG uptake is mediated by membranous GLUT-1 expression in GSRC.

A primary gastrointestinal stromal tumor (GIST) arising in the liver is extremely rare. In our case of GIST, CT and MRI showed a well-defined, weakly enhancing mass with a cystic component in the left lateral segment of the liver that showed homogeneous and avid (18)F-fluorodeoxyglucose ((18)F-FDG) accumulation on positron emission tomography/computed tomography (PET/CT). We herein present a rare case of primary malignant GIST of the liver presenting with peritoneal seeding on CT, gadoxetic acid-enhanced MRI and (18)F-FDG PET/CT.