The aim of this study was to investigate the efficacy of 11C-choline PET/CT imaging for lung cancer and the correlation between choline uptake of lung cancer tissue and the expression of choline kinase (ChoK), phosphorylcholine-cytidyl transferase and Ki-67 index. Between March 2008 and June 2010, 53 patients diagnosed or suspected of having lung cancer underwent integrated 11C-choline PET/CT and contrast-enhanced CT scans before surgery. After surgery, specimens from 42 patients diagnosed with lung cancer were used to detect the expression of ChoK, phosphorylcholine-cytidyl transferase and the Ki-67 index. The PET/CT results were analyzed using visual methods and the standardized uptake value (SUV) of lesions was measured using semi-quantitative methods. Finally, the analyzed results were compared to the histopathological results. The accuracy of the 11C-choline PET/CT for diagnosing lung cancer was 81.13% (43/53), compared with 71.70% (38/53) for CT scanning. The difference was not statistically significant (P=0.61). The accuracy of 11C-choline PET/CT for diagnosing lymph nodes was 83.76% (227/271), compared with 66.79% (181/271) for CT scanning. This difference was statistically significant (P=0.04); the SUVmean value of lesions correlated positively with the Ki-67 index (r=0.51, p=0.002). Of the 35 patients with positive 11C-choline PET results, 29 (82.86%) overexpressed ChoK, 26 (74.29%) overexpressed phosphorylcholine-cytidyl transferase. The seven patients with negative 11C-choline PET results did not exhibit overexpression of ChoK or phosphorylcholine-cytidyl transferase; the SUVmean value correlated positively with the expression of both ChoK and phosphorylcholine-cytidyl transferase (r=0.52, p=0.001; r=0.37, p=0.029). In conclusion, compared with contrast-enhanced CT, 11C-choline PET offers nodal staging with higher accuracy. The SUV value of PET is correlated with the proliferation of tumor cells and the mechanism of PET imaging is associated with the overexpression of ChoK and phosphorylcholine-cytidyl transferase.

FDG PET-CT imaging is increasingly accepted as a modality for evaluation of many malignancies, but FDG also can be accumulated intensely by inflammatory lesions. We present a case of a 60-year-old woman with intermittent fever, chills, fatigue, and dyschezia. CT scans indicated colon carcinoma with thoracic and retroperitoneal lymph node metastases. Whole body FDG PET-CT was performed to confirm and stage the malignant disease and showed intense FDG uptake in those lesions. However, histopathology confirmed tuberculosis. The literature describing FDG accumulation in constitutional tuberculous lesions is sparse, and one must be aware of patterns of FDG accumulation in tuberculosis in the diagnosing malignancies.

Background: Cholangiocarcinoma (CCA), which consists of intrahepatic CCA (iCCA), perihilar CCA (pCCA), and distal CCA (dCCA), is an aggressive malignancy worldwide. PCCA and dCCA are often classified as extrahepatic CCA (exCCA). However, the differences in mutational characteristics between pCCA and dCCA remain unclear.Methods: Deep sequencing targeting of 450 cancer genes was performed for genomic alteration detection.The tumor mutational burden (TMB) was measured by an algorithm developed in-house. Correlation analysis was conducted using Fisher's exact test.Results: FGFR2 and ERBB2 mutations mainly occurred in iCCA and exCCA, respectively. In exCCA, the frequencies of PIK3CA, FAT4, KDM6A, MDM2, and TCF7L2 mutations were significantly higher in pCCA compared to dCCA, while the frequencies of TP53 and KRAS mutations were markedly lower in pCCA than those in dCCA. The prognosis-related mutations were different among the CCA subtypes. NF1 mutation was associated with short disease-free survival (DFS) and overall survival (OS), and ERBB2 mutation was associated with short DFS in dCCA patients. Meanwhile, MAP2K4 mutation was associated with long DFS and OS, and TERT mutation was associated with short DFS in pCCA. A series of mutations in genes, including ARID1A, ARID2, SMAD4, TERT, TP53, and KRAS, were found to be associated with the TMB.Conclusions: In this study, we investigated the comprehensive genomic characterizations of CCA patients, identified the significant alterations in each subtype, and identified potential biomarkers for prognosis prediction. These results provide molecular evidence for the heterogeneity of CCA subtypes and evidence for further precision targeted therapy of CCA patients.

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