Solitary pulmonary nodule (SPN) is defined as a rounded opacity≤3 cm in diameter surrounded by lung parenchyma. The majority of smokers who undergo thin-section CT have SPNs, most of which are smaller than 7 mm. In the past, multiple follow-up examinations over a two-year period, including CT follow-up at 3, 6, 12, 18, and 24 months, were recommended when such nodules are detected incidentally. This policy increases radiation burden for the affected population. Nodule features such as shape, edge characteristics, cavitation, and location have not yet been found to be accurate for distinguishing benign from malignant nodules. When SPN is considered to be indeterminate in the initial exam, the risk factor of the patients should be evaluated, which includes patients' age and smoking history. The 2005 Fleischner Society guideline stated that at least 99% of all nodules 4 mm or smaller are benign; when nodule is 5-9 mm in diameter, the best strategy is surveillance. The timing of these control examinations varies according to the nodule size (4-6, or 6-8 mm) and the type of patients, specifically at low or high risk of malignancy concerned. Noncalcified nodules larger than 8 mm diameter bear a substantial risk of malignancy, additional options such as contrast material-enhanced CT, positron emission tomography (PET), percutaneous needle biopsy, and thoracoscopic resection or videoassisted thoracoscopic resection should be considered.
The main purpose of this study is to evaluate the clinical value of 18F-fluorodeoxyglucose (18F-FDG) metabolism imaging in accurate staging and prognosis prediction before treatment of cervical cancer. 18F-FDG single photon emission computed tomography (SPECT/CT) was performed before treatment on 27 patients with cervical cancer and was analyzed retrospectively. All the images were analyzed by image fusion software. Meanwhile, primary tumor size and T/B, lymph nodes size and T/B were measured by software. Comparison of the relationship between primary tumor T/B of cervix and clinic pathological factors was performed using SPSS17.0. The diagnosis was established according to pathology results of surgery or/and multi-modalities of imaging and clinical following up. The results showed that the primary tumor T/B value of cervix was 5.9 (3.2). With the increased clinical stage, T/B of primary tumor value was significantly increased (P<0.05). The T/B value in patients ≥Ⅱa stage was significantly higher than those of ≤Ⅰb stage. There were no significant correlations between T/B value and primary tumor size, lymph-node metastasis, and histological type (P>0.05). Thirteen lymph nodes were detected by 18F-FDG imaging in 27 patients with cervical cancer. For diagnosing lymph nodes metastasis, the sensitivity, specificity, accuracy, positive and negative predictive value by 18F-FDG imaging were 75.0%, 78.9%, 77.8%, 60.0% and 88.2%, respectively. The T/B value of all lymph nodes was 6.3 (3.5), in which T/B value of distant metastasis was significantly higher than that of the pelvic metastasis (P<0.05). There were no significant correlations between T/B value and the size of lymph nodes (P>0.05). Uterine body uptaking FDG were discovered in 17 patients and 15 cases were then pathologically proved. Two of 15 cases were cancerous invasion of uterine body, and the other 13 cases were physiological changes of endometrial, and the T/B value of the former was significantly higher than that of the latter (P<0.05). There were positive correlation between invasion of uterine body and lymph nodes metastasis (P<0.05). In conclusion, 18F-FDG imaging has an obvious value for the diagnosis of outside pelvic and distant lymph node metastasis, uterine body infiltrated, and accurate staging. Primary focal T/B value of cervical cancer associates with the clinical stage, which can reflect the risk of patients, and were useful to preliminarily predict the prognosis of cervical cancer.
Prostate cancer ranks second among the causes of death of malignant tumors in middle-aged and elderly men. A considerable number of patients are not easily detected in early-stage prostate cancer. Although traditional imaging examinations are of high value in the diagnosis and staging of prostate cancer, they also have certain limitations. With the development of nuclear medicine instruments and molecular probes, molecular imaging is playing an increasingly important role in the diagnosis and treatment of prostate cancer. Positron emission tomography and computed tomography (PET/CT) using prostate-specific membrane antigen (PSMA) as a probe has gained increasing recognition. This article will review the latest progress in the application of PET/CT using probes for targeting PSMA to imaging and treatment of prostate cancer, in order to provide a theoretical basis for the application of probes for targeting PSMA in the diagnosis and treatment of prostate cancer.