Objective To determine the added value of CT over planar and SPECT-only imaging in the diagnosis of musculoskeletal infection using 99m Tc-UBI 29-4. Materials and methods 184 patients with suspected musculoskeletal infection who underwent planar and SPECT/CT imaging with 99m Tc-UBI 29-41 were included. Planar, SPECT-only and SPECT/CT images were reviewed by two independent analysts for presence of bone or soft tissue infection.

Medical imaging techniques play a central role in clinical oncology, helping to obtain important information about the extent of disease, and plan treatment. Advanced imaging modalities such as Positron Emission Tomography–Computed Tomography (PET/CT), may help in the whole-body staging in a single procedure, although the lesions should be carefully interpreted. PET/CT is becoming commonly used in canine cancer patients, but there is still limited information available on specific tumors such as mammary cancer. We evaluated the utility of fluorine-18 fluorodeoxyglucose ( 18 F-FDG)-PET/CT to detect malignant lesions in eight female dogs with naturally occurring mammary tumors. A whole-body scan was performed prior to surgery, and mammary and non-mammary lesions detected either on PET/CT or during pre-surgical physical exam were resected when possible and submitted for histopathological examination. Multiple mammary lesions involving different mammary glands were detected in 5/8 dogs, for a total of 23 lesions; there were 11 non-mammary-located lesions in 6/8 dogs, three of these were lung or lymph node metastasis. A total of 34 lesions were analyzed: 22 malignant (19 mammary tumors and three metastatic lesions), and 12 benign (four mammary lesions and eight of non-mammary tissues). Glucose uptake by maximum standardized uptake value (SUVmax) was analyzed and correlated with tumor size, and benign vs. malignant pathology. We found that the minimum tumor size needed to distinguish malignant lesions according to the SUVmax was 1.5 cm; benign and malignant lesions <1.5 cm did not differ in glucose uptake (mean SUVmax = 1.1). In addition, a SUVmax value >2 was 100% sensitive for malignancy. Combining these data, lesions >1.5 cm with a SUVmax >2 had a positive predictive value of 100%. Finally, we did not find an association between SUVmax and histologic subtype or grade, which may be present in a larger sample. Thus, 18 F-FDG PET/CT is useful for distinguishing malignant from benign lesion but further imaging of dogs with diverse tumors, should establish characteristic SUV value cutoffs for detecting primary and metastatic disease, and distinguishing them from benign lesions.

An early discrimination of survival probability is required for patients with diffuse large B cell lymphoma (DLBCL), which may identify patients that require other treatment options, for example clinical trials. To the best of our knowledge, the impact of interim evaluation with 18fluorodeoxyglucose positron emission tomography-computed tomography (18F-FDG PET/CT) has not yet been determined in this type of neoplasia. The aim of the present study was to determine the role of changes in metabolic tumor volume (MTV) between baseline and interim 18F-FDG PET/CT scans, following three courses of chemotherapy in order to predict complete response (CR) and overall survival (OS) in patients with DLBCL. Patients with previously untreated DLBCL who had received the standard 6–8 cycles of rituximab, cyclophosphamide, doxorubicin, vincristine and prednisone were included in the present study. A predictive model was constructed using changes in MTV and other clinical factors including age, gender, East Cooperative Oncology Group (ECOG) status, clinical stage, B symptoms, the presence of bulky disease and elevated lactate dehydrogenase levels, and data were analyzed using logistic regression analysis. In total, 50 patients with DLBCL were included in the present study. The majority of patients presented with stage III/IV disease (64%), B symptoms (72%) and bulky disease (58%). According to the International Prognostic Index score, 44% of patients were in the intermediate-high or high-risk categories for risk of relapse, and therefore considered to have poor prognosis. In total, ≥94% of patients achieving a decrease in total MTV had a 2-year OS rate of 95%, compared with the 58% OS rate of those with a suboptimal response. A multivariate model, including a change in MTV (a decrease of ≥94%), the ECOG performance status ≥2, a change in leukocyte counts and age, was used to predict CR. This model was used to define two groups according to the predicted probability of recurrence (cutoff, 0.69). The 2-year survival rates of the two groups were 95 and 59%, respectively. Analysis of changes in MTV in the interim 18F-FDG PET/CT revealed significant prognostic value for the prediction of CR and OS in patients with DLBCL.

Background. Although chemotherapy added to rituximab is a standard of care for diffuse large B cell lymphoma (DLBCL), treatment of patients ≥65 years of age remains controversial due to comorbidities. Methods. This is a retrospective, comparative, nonrandomized study of patients ≥65 years of age, who were diagnosed with DLBCL but not previously treated. Demographic characteristics and comorbidities were analyzed. Three rituximab-containing treatment regimens (standard RCHOP, anthracycline dose-reduced RChOP, and RCOP) were compared. Descriptive analyses were conducted. Survival was calculated with the Kaplan-Meier method, and differences were compared with the log-rank test. Results. In total, 141 patients with a median age of 73.9 years were studied. The three treatment groups had comparable demographic characteristics. The overall response was 77%, 72.5%, and 59% in groups treated with RCHOP, RChOP, and RCOP, respectively. After multivariate analysis, the factors influencing the overall survival were the presence of B symptoms, poor performance status (ECOG ≥ 3), and febrile neutropenia. Factors influencing disease-free survival were febrile neutropenia, high-intermediate and high-risk IPI scores, and treatment without anthracycline. Conclusion. A higher ORR (overall response rate) was achieved with standard RCHOP, which influenced DFS and OS, although it was not statistically significant compared with the other groups. Interventional phase 3 trials testing new molecules in patients aged 70 to 80 years and older are required to improve the prognosis within this growing population.

This Bombesin (BBN), a tetradecapeptide analog of human gastrin-releasing peptide (GRP) with a high binding affinity for GRP receptors (GRPR), is overexpressed in early stages of androgen-dependent prostate carcinomas, but not in advanced stages. Therefore, there is a need to develop effective tracers for the accurate and specific detection of this disease. The objective of this study was to evaluate Lys 1 , Lys 3 -DOTA-BBN (1,14) analog with the radiolabeled positron emitter [ 68 Ga]-Ga-BBN for receptor imaging with PET, and to determine its biodistribution and radiation dosimetry using whole-body (WB) PET scans in healthy volunteers. The highest uptake was in the pancreas, followed by urinary bladder. The critical organ was pancreas with a mean absorbed dose of 206 ± 0.7, 210 ± 0.7, 120 ± 0.9, 390.23 ± 0.6 µGy/MBq and the effective doses were estimated as 73.2 ± 0.6, 49.8 ± 0.3 µGy/MBq (women and men, respectively).