Head-to-Head Comparison of [18F]FDG PET Imaging and MRI for the Detection of Recurrence or Residual Tumor in Patients with Nasopharyngeal Carcinoma: A Meta-Analysis.

BACKGROUND: This meta-analysis compared the diagnostic performance of [18F] fluorodeoxyglucose ([18F]FDG) positron emission tomography/computed tomography (PET/CT) or PET versus Magnetic resonance imaging (MRI) in detecting recurrence or residual tumors at the primary site in patients with nasopharyngeal carcinoma (NPC). METHODS: A comprehensive literature search was conducted in the PubMed/MEDLINE and CENTRAL databases to find studies with at least 20 patients with NPC undergoing both [18F]FDG PET/CT (or [18F]FDG PET) and MRI for detecting recurrence or assessing residual disease at the primary site. The pooled sensitivity and specificity of PET/CT and MRI were calculated with 95% confidence intervals (CIs) and compared. RESULTS: Five studies, including 1908 patients (six patient groups), were included. PET imaging had higher sensitivity [93.3% (95% CI: 91.3-94.9%); I2 = 52.6%] compared to MRI [80.1% (95% CI: 77.2-82.8%); I2 = 68.3%], but the specificity of the two modalities was similar: 93.8% (95% CI: 92.2-95.2%; I2 = 0%) for PET/CT and 91.8% (95% CI: 90.1-93.4%; I2 = 94.3%) for MRI. The areas under the curve (AUCs) for PET/CT and MRI were 0.978 and 0.924, respectively, without significant difference (p = 0.23). CONCLUSIONS: This meta-analysis suggests that [18F]FDG PET imaging and MRI do not significantly differ in diagnostic performance. Nevertheless, [18F]FDG PET imaging shows higher sensitivity than MRI.

The Role of [18F]FDG PET/CT in Predicting Toxicity in Patients with NHL Treated with CAR-T: A Systematic Review.

CAR-T-cell therapy, also referred to as chimeric antigen receptor T-cell therapy, is a novel method in the field of immunotherapy for the treatment of non-Hodgkin's lymphoma (NHL). In patients receiving CAR-T-cell therapy, fluorodeoxyglucose Positron Emission Tomography/Computer Tomography ([18F]FDG PET/CT) plays a critical role in tracking treatment response and evaluating the immunotherapy's overall efficacy. The aim of this study is to provide a systematic review of the literature on the studies aiming to assess and predict toxicity by means of [18F]FDG PET/CT in patients with NHL receiving CAR-T-cell therapy. PubMed/MEDLINE and Cochrane Central Register of Controlled Trials (CENTRAL) databases were interrogated by two investigators to seek studies involving the use of [18F]FDG PET/CT in patients with lymphoma undergoing CAR-T-cell therapy. The comprehensive computer literature search allowed 11 studies to be included. The risk of bias for the studies included in the systematic review was scored as low by using version 2 of the "Quality Assessment of Diagnostic Accuracy Studies" tool (QUADAS-2). The current literature emphasizes the role of [18F]FDG PET/CT in assessing and predicting toxicity in patients with NHL receiving CAR-T-cell therapy, highlighting the evolving nature of research in CAR-T-cell therapy. Additional studies are warranted to increase the collected evidence in the literature.

The Correlation of Body Mass Index with Risk of Recurrence in Post-Menopausal Women with Breast Cancer Undergoing Fluorodeoxyglucose Positron Emission Tomography/Computed Tomography.

Background: The aim of this study was to investigate whether high body mass index (BMI) increases the risk of recurrence and correlates with higher glucose uptake in recurrent lesions in post-menopausal female patients with breast cancer. Methods: A hospital database was searched to retrieve breast cancer patients who had undergone an [18F]FDG PET/CT scan before neoadjuvant chemotherapy and curative-intent surgery. BMI was calculated at the baseline [18F]FDG PET/CT scan. There was a median follow-up of 5 years after the baseline PET/CT scan to identify recurrence in the breast (T_rec); lymph nodes (N_rec); and distant locations (M_rec). Furthermore, SUVmax was measured at the sites of recurrence. A chi-square test was used to investigate any difference in the frequency of any recurrence, T_rec, N_rec, and M_rec, between overweight women (BMI ≥ 25 kg/m2) and women with a BMI < 25 kg/m2 (p < 0.05). SUVmax was compared using a t-test (p < 0.05) between the two groups. Results: A total of 142 post-menopausal patients (BMI: 26.84 ± 5.59; 84 overweight and 58 with normal weight) were retrieved from the database. There were 48 recurrences at the follow-up. The chi-square test demonstrated in overweight women an increased frequency of any recurrence (35 vs. 13; p = 0.025) and T_rec (15 vs. 2; p = 0.018) and a higher T_rec SUVmax (4.74 ± 2.90 vs. 1.85 ± 0.63; p = 0.09) compared to women with a BMI < 25 kg/m2. Conclusions: BMI seems to correlate with an increased rate of recurrence, especially in the breast, and a higher glucose uptake in post-menopausal patients with recurrent breast cancer.

Scintigraphic evaluation of colonic motility in patients with anorectal malformations and constipation.

BACKGROUND AND PURPOSE: Constipation is one of the major sequelae in patients after correction of anorectal anomalies (ARAs). The aim of the present work has been to assess the colonic transit time, using radioisotope scintigraphy, in patients operated for ARA and experiencing constipation in the follow-up. The results were compared with transit time from children with true functional constipation. METHODS: Twelve or 32 patients operated for ARA during the period 1994-2003 experienced mild or severe constipation (6 with high or intermediate form of ARA and 6 with low type) at follow-up. The mean age of this group was 5.8 years. Eighteen patients, mean age 6.7 years, with true functional constipation were studied as well. Colonic transit times were investigated using radioisotope scintigraphy. Normal values for colonic transit time were derived from historical controls. Radioisotope diethylenetriamine pentaacetic acid labelled with indium 111 was administered orally to determine a segmental colonic transit. Images of the abdomen have been taken at 6, 24, 48, and again at 72 hours, if radioactivity was not cleared from the colon. To quantify colonic transit, we calculated the geometric centre (GC) dividing the colon into anatomic regions. RESULTS: According to normal controls, 2 different type of delayed transit can be observed: (a) slow-transit constipation if GC at 48 hours is less than 4.1; (b) functional rectosigmoid obstruction (FRSO) if GC at 48 hours is 4.1 or more but less than 6.1 at 72 hours. Patients with functional constipation were divided into 2 groups: (a) slow-transit constipation in 12 patients with a GC at 48 hours of 3.7 +/- 0.5; (b) FRSO in 6 patients with a GC of 4.7 +/- 0.04 and 5.02 at 48 and 72 hours, respectively. Patients operated for high ARA had values characteristic of FRSO with GC at 48 hours of 5.1 +/- 0.8 and 4.75 +/- 0.5 at 72 hours. In low ARA, the transit times were similar to the ones observed in patients with high ARA at 48 hours with a GC of 4.9 +/- 0.5. CONCLUSIONS: Patients with ARA frequently have functional sequelae in the postoperative period such as constipation. According to our results, constipation seems to be secondary to segmental motility disorders limited to the rectosigmoid area, similar to constipated children with FRSO. No evidence of more generalised motility disturbance, as previously postulated, could be recorded.