Prognostic significance of MRI-based late-course tumor volume in locoregionally advanced nasopharyngeal carcinoma.

BACKGROUND: To validate tumor volume-based imaging markers for predicting local recurrence-free survival (LRFS) in locoregionally advanced nasopharyngeal carcinoma patients, who underwent induction chemotherapy followed by definitive intensity-modulated radiotherapy. METHODS: We enrolled 145 patients with stage III-IVA nasopharyngeal carcinoma in this retrospective study. Pre-treatment tumor volume (Vpre) and late-course volume (LCV) were measured based on the MRIs scanned before treatment and during the first 3 days in the sixth week of radiotherapy, respectively. The volume regression rate (VRR) was calculated according to Vpre and LCV. Receiver operating characteristic (ROC) curves were used to identify the cut-off best separating patient subgroups in assessing the prognostic value of Vpre, LCV and VRR. The Kaplan-Meier method was used for survival analysis. Prognostic analyses were performed using univariate and multivariate COX proportional hazard models. RESULTS: The LCV was 5.3 ± 0.5 (range 0-42.1) cm3; The VRR was 60.4 ± 2.2% (range 2.9-100.0). The median follow-up period was 36 months (range 6-98 months). The cut-off value of LCV determined by the ROC was 6.8 cm3 for LRFS prediction (sensitivity 68.8%; specificity 79.8%). The combination of LCV and VRR for LRFS prediction (AUC = 0.79, P < 0.001, 95% CI 0.67-0.90), LCV (AUC = 0.74, P = 0.002, 95% CI 0.60-0.88) and Vpre (AUC = 0.71, P = 0.007, 95% CI 0.56-0.85) are better than T category (AUC = 0.64, P = 0.062, 95% CI 0.50-0.79) alone. Patients with LCV ≤ 6.8 cm3 had significantly longer LRFS (P < 0.001), disease-free survival (DFS, P < 0.001) and overall survival (OS, P = 0.005) than those with LCV > 6.8 cm3. Multivariate Cox regression showed LCV was the only independent prognostic factor for local control (HR = 7.80, 95% CI 2.69-22.6, P < 0.001). CONCLUSIONS: LCV is a promising prognostic factor for local control and chemoradiosensitivity in patients with locoregionally advanced NPC. The LCV, and the combination of LCV with VRR are more robust predictors for patient survival than T category.

MiR-501 promotes tumor proliferation and metastasis by targeting HOXD10 in endometrial cancer.

BACKGROUND: Several studies have shown the crucial role of miR-501 in regulating cellular pathology in various cancers. However, the function and expression of miR-501 in endometrial cancer (EC) remain obscure. METHODS: The expression of miR-501 was determined using quantitative real-time PCR. MTT assay, colony formation assay and cell cycle analysis were used to evaluate the proliferation ability. Migration and invasion were assessed using transwell assay. Tumor formation in nude mice was used to observe the effects of miR-501 on cell proliferation and migration in vivo. Luciferase assay, quantitative real-time PCR and western blot were applied to determine that HOXD10 was the target gene of miR-501. RESULTS: In this study, we observed significantly up-regulated expression of miR-501 in endometrial cancer, which correlated with higher pelvic lymph node metastasis and shorter overall survival in high-grade endometrial cancer. High expression of miR-501 was also found in the copy-number-high group than other groups. Moreover, in vitro and in vivo assay showed that overexpression of miR-501 can promote proliferation and metastasis. Mechanistically, we found that miR-501 promotes tumor progression by directly targeting HOXD10. Further study also indicated that miR-501 overexpression can activate the AKT/mTOR pathway. CONCLUSIONS: MiR-501, which functions as an oncomir in endometrial cancer, might be a potential therapeutic target in high grade endometrial cancer.

Dosimetric Evaluation of the QFix kVueTM Calypso Couch Top.

PURPOSE: To evaluate the dosimetric accuracy of the default couch model of the QFix kVueTM Calypso couch top in the treatment planning system. METHODS: With the gantry 180°, field size 20 × 20 cm, 6 MV, we measured the depth dose, off-axis dose, and dose plane of different depths in the phantom with the couch rails in and out, respectively. Isocenter doses at different angles were also obtained. The results were compared to the doses calculated using the default couch top model and the real scanned couch top model. Then we revised the default model according to the measured results. RESULTS: With "Rails In," the depth dose, off-axis dose, and dose plane of the default couch top model had a big difference with the dose of the real scanned couch top model and the measured result. The dose of the real scanned couch top model was much closer to the measured result, but in the region of the rail edge, the difference was still significant. With "Rails Out," there was a minor difference between the measured result, the dose of the default couch top model and the real scanned couch top model. The difference between the measurement and the default couch top model became very small after being revised. CONCLUSIONS: It is better to avoid the beam angle passing through the couch rails in treatment plans, or you should revise the parameter of the QFix kVueTM Calypso couch top model based on the measured results, and verify the treatment plan before clinical practice.