Xiaorong Hou

Timing of adjuvant radiotherapy for early-stage endometrial carcinoma: a single-center retrospective cohort study

To investigate the appropriate timing of radiotherapy (RT) after hysterectomy in women with early-stage endometrial cancer (EC). We analyzed the data of 1,062 patients with early-stage EC who underwent postoperative RT at our hospital between April 1999 and November 2020. Restricted cubic spline were used to explore the relationship between the surgery-radiotherapy interval (SRI) and local recurrence-free survival (LRFS). The maximally selected rank statistics method was used to identify the optimal threshold for SRI. The overall survival (OS), disease-free survival (DFS), LRFS, and distant metastasis-free survival (DMFS) rates were estimated using the Kaplan-Meier method. Multivariate analysis was performed using the Cox proportional hazards regression. In entire cohort, patients with SRI ≥42 days had worse survival. In multivariate analysis, SRI was an independent prognostic factor for OS (p=0.011), DFS (p=0.019), LRFS (p=0.013) and DMFS (p=0.050). However, in piecewise Cox regression, the significance of SRI for DMFS disappeared. In the subgroup analysis, the optimal cut-off value for SRI in the high-intermediate risk (HIR) and high-risk (HR) groups was 33 days. Multivariate analysis showed that SRI was an independent prognostic factor only for LRFS (p=0.033) and marginally associated with OS (p=0.055). The timing of postoperative RT is crucial in patients with early-stage EC. Adjuvant RT should be initiated as soon as the vaginal cuff is healed, while for HIR and HR patients, it should be initiated within 33 days.

Practice patterns of adjuvant radiotherapy in women with stage I to II endometrial carcinoma: a real-world multi-institutional analysis in China

Abstract Background This study aimed to report clinical practice patterns of postoperative radiotherapy for stage I to II endometrial carcinoma (EC) patients treated in 13 Chinese medical centers. Methods We included early stage EC patients treated by hysterectomy and adjuvant RT between 2003 and 2017 from 13 institutions. Patients were classified into 4 risk groups based on ESMO-ESGO-ESTRO recommendations (2014). Results A total of 1,227 cases were analyzed. Along the 15 years of the study, an increasing tendency was found towards administration for vaginal brachytherapy (VBT) alone, while the proportion of external beam pelvic radiotherapy (EBRT) alone remained stable in the corresponding period. When radiation modalities were stratified by risk groups, proportion of VBT alone significantly increased in all risk groups. The higher the risk, the later VBT became the main adjuvant treatment modality. However, EBRT alone or with VBT remained the main adjuvant method for high-risk patients. There were 13 dose-fractionation schemes for VBT alone with the scheme of 30 Gy in 6 fractions prescribed at 0.5cm under the vaginal mucosa accounting for most. There were 17 schemes for VBT boost and the most common schedule was 10 Gy in 2 fractions. The upper 3–5cm part of vagina was the most frequent target. 89.6% of the practitioners performed two-dimensional VBT technique. The median dose for EBRT was 50 Gy. From 2003 to 2017, conventional radiotherapy was gradually replaced by three-dimensional conformal radiotherapy modality and intensity modulated radiotherapy. Conclusion We report a significant shift from EBRT to VBT alone for high-intermediate-risk, intermediate-risk and low-risk EC patients from 2003 to 2017 while EBRT remained the main radiation modality for high-risk early stage patients. There has been remarkable heterogeneity among VBT dose fractionation schedules across China. Trial registration The clinical trial ID was ChiCTR-PRC-17010712. It was authorized by the Institutional Review Board of Peking Union Medical College Hospital (N0. S-K139).

Prognostic values of tumor size and location in early stage endometrial cancer patients who received radiotherapy

To investigate the correlation between tumor size, tumor location, and prognosis in patients with early-stage endometrial cancer (EC) receiving adjuvant radiotherapy. Data of patients who had been treated for stage I-II EC from March 1999 to September 2017 in 13 tertiary hospitals in China was screened. Cox regression analysis was performed to investigate associations between tumor size, tumor location, and other clinical or pathological factors with cancer-specific survival (CSS) and distant metastasis failure-free survival (DMFS). The relationship between tumor size as a continuous variable and prognosis was demonstrated by restricted cubic splines. Prognostic models were constructed as nomograms and evaluated by Harrell's C-index, calibration curves and receiver operating characteristic (ROC) curves. The study cohort comprised 805 patients with a median follow-up of 61 months and a median tumor size of 3.0 cm (range 0.2-15.0 cm). Lower uterine segment involvement (LUSI) was found in 243 patients (30.2%). Tumor size and LUSI were identified to be independent prognostic factors for CSS. Further, tumor size was an independent predictor of DMFS. A broadly positive relationship between poor survival and tumor size as a continuous variable was visualized in terms of hazard ratios. Nomograms constructed and evaluated for CSS and DMFS had satisfactory calibration curves and C-indexes of 0.847 and 0.716, respectively. The area under the ROC curves for 3- and 5-year ROC ranged from 0.718 to 0.890. Tumor size and LUSI are independent prognostic factors in early-stage EC patients who have received radiotherapy. Integrating these variables into prognostic models would improve predictive ability.