Apparent Diffusion Coefficient on Diffusion-Weighted Magnetic Resonance Imaging to Predict the Prognosis of Patients with Endometrial Cancer: A Meta-Analysis.

Apparent diffusion coefficient (ADC) derived from diffusion-weighted magnetic resonance imaging (DWI) may help diagnose endometrial cancer (EC). However, the association between ADC and the recurrence and survival of EC remains unknown. We performed a systematic review and meta-analysis to investigate whether pretreatment ADC on DWI could predict the prognosis of women with EC. PubMed, Embase, and Cochrane's Library were searched for relevant cohort studies comparing the clinical outcomes between women with EC having low versus high ADC on pretreatment DWI. Two authors independently conducted data collection, literature searching, and statistical analysis. Using a heterogeneity-incorporating random-effects model, we analyzed the results. In the meta-analysis, 1358 women with EC were included from eight cohort studies and followed for a median duration of 40 months. Pooled results showed that a low pretreatment ADC on DWI was associated with poor disease-free survival (DFS, hazard ratio [HR]: 3.29, 95% CI: 2.04 to 5.31, p < 0.001; I2 = 41%). Subgroup analysis according to study design, tumor stage, MRI Tesla strength, ADC cutoff, follow-up duration, and study quality score showed consistent results (p for subgroup analysis all > 0.05). The predictive value of low ADC for poor DFS in women with EC decreased in multivariate studies compared to univariate studies (HR: 2.59 versus 32.57, p = 0.002). Further studies showed that a low ADC was also associated with poor overall survival (HR: 3.36, 95% CI: 1.33 to 8.50, p = 0.01, I2 = 0). In conclusion, a low ADC on pretreatment DWI examination may predict disease recurrence and survival in women with EC.

Fusion imaging versus ultrasound-guided percutaneous thermal ablation of liver cancer: a meta-analysis.

BACKGROUND: Ultrasound-guided percutaneous thermal ablation has become an alternative treatment for small hepatocellular carcinoma (HCC). Recent evidence suggests that fusion imaging (FI) may improve the feasibility and efficacy of thermal ablation for HCC, while the clinical evidence remains limited. PURPOSE: To compare FI versus ultrasound-guided thermal ablation for HCC. MATERIAL AND METHODS: Relevant cohort or randomized controlled trials were found by searching Medline, Web of Science, Cochrane Library, and Embase. The pooling of results was performed using a random-effects model incorporating heterogeneity. RESULTS: In this meta-analysis, 15 studies involving 1472 patients (1831 tumors) for FI-guided ablation and 1380 patients (1864 tumors) for ultrasound-guided ablation were included. Pooled results showed that compared to conventional HCC ablation guided by ultrasound, the FI-guided procedure showed a similar technique efficacy rate (risk ratio [RR] = 1.01, 95% confidence interval [CI] = 1.00-1.02, P = 0.25; I2 = 30%). However, FI-guided tumor ablation was associated with a lower incidence of overall complications (RR = 0.70, 95% CI = 0.50-0.97, P = 0.03; I2 = 0%). Moreover, patients receiving FI-guided tumor ablation had a lower risk of local tumor progression during follow-up than those with ultrasound-guided ablation (RR = 0.61, 95% CI = 0.47-0.78, P < 0.001; I2 = 13%). Subgroup analysis according to FI strategy, imaging techniques in controls, and tumor diameter showed consistent results (p for subgroup difference all >0.05). CONCLUSION: FI-guided thermal ablation may be more effective and safer than ultrasound-guided ablation for patients with HCC.

Reduced lung dose during radiotherapy for thoracic esophageal carcinoma: VMAT combined with active breathing control for moderate DIBH.

BACKGROUND: Lung radiation injury is a critical complication of radiotherapy (RT) for thoracic esophageal carcinoma (EC). Therefore, the goal of this study was to investigate the feasibility and dosimetric effects of reducing the lung tissue irradiation dose during RT for thoracic EC by applying volumetric modulated arc radiotherapy (VMAT) combined with active breathing control (ABC) for moderate deep inspiration breath-hold (mDIBH). METHODS: Fifteen patients with thoracic EC were randomly selected to undergo two series of computed tomography (CT) simulation scans with ABC used to achieve mDIBH (representing 80% of peak DIBH value) versus free breathing (FB). Gross tumor volumes were contoured on different CT images, and planning target volumes (PTVs) were obtained using different margins. For PTV-FB, intensity-modulated radiotherapy (IMRT) was designed with seven fields, and VMAT included two whole arcs. For PTV-DIBH, VMAT with three 135° arcs was applied, and the corresponding plans were named: IMRT-FB, VMAT-FB, and VMAT-DIBH, respectively. Dosimetric differences between the different plans were compared. RESULTS: The heart volumes decreased by 19.85%, while total lung volume increased by 52.54% in mDIBH, compared to FB (p < 0.05). The mean conformality index values and homogeneity index values for VMAT-DIBH (0.86, 1.07) were slightly worse than those for IMRT-FB (0.90, 1.05) and VMAT-FB (0.90, 1.06) (p > 0.05). Furthermore, compared to IMRT-FB and VMAT-FB, VMAT-DIBH reduced the mean total lung dose by 18.64% and 17.84%, respectively (p < 0.05); moreover, the V5, V10, V20, and V30 values for IMRT-FB and VMAT-FB were reduced by 10.84% and 10.65% (p > 0.05), 12.5% and 20% (p < 0.05), 30.77% and 33.33% (p < 0.05), and 50.33% and 49.15% (p < 0.05), respectively. However, the heart dose-volume indices were similar between VMAT-DIBH and VMAT-FB which were lower than IMRT-FB without being statistically significant (p > 0.05). The monitor units and treatment time of VMAT-DIBH were also the lowest (p < 0.05). CONCLUSIONS: VMAT combined with ABC to achieve mDIBH is a feasible approach for RT of thoracic EC. Furthermore, this method has the potential to effectively reduce lung dose in a shorter treatment time and with better targeting accuracy.

RapidArc radiotherapy for whole pelvic lymph node in cervical cancer with 6 and 15 MV: a treatment planning comparison with fixed field IMRT.

Dosimetric differences were investigated among single and dual arc RapidArc and fixed-field intensity-modulated radiotherapy (f-IMRT) treatment plans for whole pelvic irradiation of lymph nodes. A total of 12 patients who had undergone radical surgery for cervical cancer and who had demonstrated multiple pelvic lymph node metastases were treated with radiotherapy. For all 12 cases, 7-field IMRT, single-arc RapidArc and dual-arc RapidArc were applied with 6 MV and 15 MV X-ray energies. The radiation dosimetric parameters for the different plans were compared with one another. All the plans met the clinical requirements. The homogeneity, conformity and external volume indices of f-IMRT and dual-arc RapidArc were better than for single-arc RapidArc (P < 0.05), while the differences between f-IMRT and dual-arc RapidArc were not significant. There were no significant differences in the radiation dose to organs at risk, except for the small bowel receiving >40 Gy (f-IMRT and dual-arc < single-arc, P < 0.05). The differences in dose distributions between the two applied X-ray energies for each of the modality plans were not significant. RapidArc plans resulted in fewer monitor units than the corresponding f-IMRT plans. Also, there were no differences between the two photon energies, except for a reduction in the number of MUs for 15 MV (P > 0.05). Compared to f-IMRT, no significant dosimetric benefits were found using RapidArc for whole pelvic lymph node irradiation. However, RapidArc has been associated with shorter treatment time and fewer monitor units, supporting the case for its safety and efficacy for pelvic irradiation.