Long-term outcomes using adjuvant pelvic intensity modulated radiation therapy (IMRT) for endometrial carcinoma

Prospective randomised phase II trial evaluating adjuvant pelvic radiotherapy using either IMRT or 3-Dimensional planning for endometrial cancer

OBJECTIVE

To compare the incidence of grade ≥2 gastrointestinal (GI) or genitourinary (GU) toxicity for patients undergoing 3DRT versus IMRT in the postoperative setting for endometrial cancer.

METHODS

Eligible patients were post-operatively randomly assigned to one of two parallel groups in a 1:1 ratio, to have their RT delivered using either a 3DRT technique or using IMRT. The prescription dose was 45 Gy in 25 fractions over 5 weeks followed by vaginal vault brachytherapy. Toxicity was graded according to National Cancer Institute (NCI) Common Terminology Criteria for Adverse Events (CTCAE) version (v) 3.0. Fisher's exact tests were used to test for associations between toxicity and arm. Differences in dosimetric parameters for patients with or without toxicity were tested using Mann-Whitney U-tests.

RESULTS

84 patients with a median age of 62 were evaluable for primary outcome. The median follow-up was 52 months. 14 (35%) participants from the 3DRT arm and 15 (34%) from the IMRT arm experienced acute grade ≥2 GI toxicity with older patients having a statistically higher risk of grade ≥2 acute GI toxicity. 20 (50%) participants from the 3DRT arm and 25 (57%) from the IMRT arm experienced acute grade ≥2 GI or GU toxicity (p = .662). 12 (30%) patients from the 3DRT arm and 17 (39%) from the IMRT arm experienced acute grade ≥2 GU toxicity (p = .493).

CONCLUSION

Although IMRT can reduce dose to normal tissue, in this study no benefit in acute GI or GU toxicity outcome was seen.

Intensity-Modulated Radiation Therapy Reduces Patient-Reported Chronic Toxicity Compared With Conventional Pelvic Radiation Therapy: Updated Results of a Phase III Trial

Clinical trials frequently include multiple end points that mature at different times. The initial report, typically based on the primary end point, may be published when key planned coprimary or secondary analyses are not yet available. Clinical Trial Updates provide an opportunity to disseminate additional results from studies, published in JCO or elsewhere, for which the primary end point has already been reported.The purpose of this update was to determine differences in patient-reported chronic toxicity and disease outcomes with intensity-modulated radiation therapy (IMRT) compared with conventional pelvic radiation. Patients with cervical and endometrial cancers who received postoperative pelvic radiation were randomly assigned to conventional radiation therapy (CRT) or IMRT. Toxicity and quality of life were assessed using Patient-Reported Outcomes version of the Common Terminology Criteria for Adverse Events, Expanded Prostate Cancer Index Composite (EPIC) bowel and urinary domains, and Functional Assessment of Cancer Therapy-General. Between 2012 and 2015, 279 eligible patients were enrolled to the study with a median follow-up of 37.8 months. There were no differences in overall survival (P = .53), disease-free survival (P = .21), or locoregional failure (P = .81). One year after RT, patients in the CRT arm experienced more high-level diarrhea frequency (5.8% IMRT v 15.1% CRT, P = .042) and a greater number had to take antidiarrheal medication two or more times a day (1.2% IMRT v 8.6% CRT, P = .036). At 3 years, women in the CRT arm reported a decline in urinary function, whereas the IMRT arm continued to improve (mean change in EPIC urinary score = 0.5, standard deviation = 13.0, IMRT v -6.0, standard deviation = 14.3, CRT, P = .005). In conclusion, IMRT reduces patient-reported chronic GI and urinary toxicity with no difference in treatment efficacy at 3 years.

Impact of external beam pelvic radiotherapy of endometrial carcinoma: A focus on chronic digestive toxicity

PURPOSE

The standard treatment for endometrial cancer is surgery, although depending on the risk factors, adjuvant radiation therapy may also be given. It is proposed for high-risk carcinomas for which an improvement in progression-free survival though not overall survival has been shown. However, despite the development of radiotherapy treatments with intensity modulation and image guidance, adjuvant radiation therapy remains toxic to the digestive system. We aimed to investigate the incidence of digestive toxicity and the presence of any predictive factors.

MATERIALS AND METHODS

Data were retrospectively collected from patients treated with adjuvant radiotherapy for endometrial carcinoma at the Institut de cancérologie de Lorraine and centre hospitalier Émile-Durkheim between January 2010 and October 2016 and analyzed to identify factors associated with chronic digestive toxicity.

RESULTS

One hundred and thirty-nine patients received a total dose of 50Gy fractionated into 25 sessions, five per week for five weeks. The median follow-up after irradiation completion was 38 months. The incidence of gastrointestinal and rectal toxicity in all patients treated with pelvic irradiation for endometrial carcinoma was 11.1% (95% confidence interval [95%CI]: 5.4-19%) for grade 3-4 and 25.6% (95%CI: 17.0-34.9%) for grade 2-4. No factor was found to be significantly predictive of chronic digestive toxicity. At five years, the overall survival was 74.3%, (95%CI: 65.3-81.4%), progression-free survival was 69.6% (95%CI: 60.1-77.3%) and incidence of pelvic recurrence was 7.9% (95%CI: 3.8-13.9%).

CONCLUSION

Our results confirmed that pelvic radiotherapy can induce a relatively high rate of digestive toxicity but failed to identify relevant factors able to predict it.

Outcome and safety analysis of endometrial cancer patients treated with postoperative 3D-conformal radiotherapy or intensity modulated radiotherapy

BACKGROUND

We sought to analyze the toxicity rates and the treatment outcomes in endometrial cancer (EC) patients treated with postoperative three-dimensional conformal radiotherapy (3DCRT) and intensity-modulated radiotherapy (IMRT).

MATERIAL AND METHODS

The clinical data of 646 EC patients treated with postoperative adjuvant 3DCRT (265 patients, 41%) or with IMRT (381 patients, 59%) between April 2007 and August 2019 were retrospectively analyzed. The primary endpoints were treatment-related acute and late gastrointestinal (GI) and genitourinary (GU) toxicities. The secondary endpoints were LC and overall survival (OS) and disease-free survival (DFS).

RESULTS

Median follow-up time was 37 months. The rates for acute GI and GU toxicities of any grade for the entire group were 55.6% and 46.8%, respectively. Acute grade ≥2 GI toxicity was significantly less in patients treated with IMRT compared to those treated with 3DCRT (11.0% vs. 19.2%, p=.004). However, no significant difference grade ≥2 GU toxicities was observed between the 3DCRT and IMRT groups (15.1% vs. 11.0%; p=.15). Acute grade ≥2 GI and GU toxicities were higher in patients receiving systemic chemotherapy, while paraaortic field irradiation increases only the risk of acute grade ≥2 GI toxicity. Estimated 3-year late grade ≥3 GI toxicity rates in the 3DCRT- and IMRT-treated patients were 4.6% and 1.9% (p= .03), respectively. The patients treated with adjuvant ChT had higher rates of late serious GI complications than those without adjuvant ChT. No significant difference in terms of survival and disease control was observed between the 3DCRT and IMRT treatment groups. No significant factor for LC was found in the multivariate analysis.

CONCLUSION

In this multicentric study involving one of largest patient population, we found that IMRT-treated EC patients showed comparable clinical outcomes but with a lower incidence of GI toxicities compared with those treated with 3DCRT.

Real-World Evaluation of Modern Adjuvant Radiotherapy in Women with Stage IB Endometrial Cancer

The optimal adjuvant treatment for stage IB endometrial cancer remains undefined. We investigated the benefit of modern adjuvant radiotherapy for women with stage IB endometrial cancer. We retrospectively reviewed patients with surgically staged, pure stage IB endometrioid adenocarcinoma (2010 to 2018). Adjuvant modern radiotherapy consists of external-beam radiotherapy (EBRT) by intensity, volumetric-modulated arc radiotherapy, or image-guided vaginal brachytherapy (VBT). The study included 180 stage IB patients. Patients with grade 3 diseases had frequent aggressive histology patterns (lymphovascular space invasion (LVSI); low uterine segment involvement) and experienced significantly shorter recurrence-free survival (RFS) and overall survival (OS) than patients with grade 1/2 diseases. Adjuvant modern radiotherapy decreased the incidence of acute/chronic grade ≥2 gastrointestinal toxicity. In IB grade 1/2 patients, EBRT significantly lengthened survival (RFS/OS); patients with age >60 years, myometrial invasion beyond the outer third, or LVSI benefited the most from EBRT. EBRT also significantly improved survival (RFS/OS) in IB grade 3 patients, where patients with bulky tumors or LVSI benefited the most from EBRT. Therefore, EBRT may be beneficial for all stage IB patients.

Predictive factors of posttreatment fracture by definitive radiotherapy for uterine cervical cancer

PURPOSE

Fractures are known to shorten life expectancy and worsen the quality of life. The risk of fractures after radiation therapy in cervical cancer patients is known to be multifactorial. In this study, we examined risk factors for fractures in cervical cancer patients, especially by evaluating bone densities and DVH parameters for fractured bones.

MATERIALS AND METHODS

For 42 patients, clinical characteristics, pretreatment CT bone densities, and radiation dose were compared between patients with and without fractures.

RESULTS

Posttreatment fractures occurred in 25 bones among ten patients. Pretreatment CT bone densities were significantly lower in patients with fractures (P < 0.05-0.01 across sites, except for the ilium and the ischium). Although DVH parameters were also significantly associated with fractures in univariate analysis, only CT densities were significantly associated with fractures in multivariate analysis.

CONCLUSION

Pretreatment CT densities of spinal and pelvic bones, which may reflect osteoporosis, have a significant impact on the risk for posttreatment fractures.

Comparison of 3D conformal radiation therapy and intensity-modulated radiation therapy in patients with endometrial cancer: efficacy, safety and prognostic analysis

Introduction: Adjuvant whole-pelvic radiation therapy (WPRT) improves locoregional control for high-intermediate stages I-III endometrial cancer patients. Intensity modulated radiation therapy (IMRT) tends to replace the standard 3D conformal radiation therapy (3DCRT) technique used in trials. Material and methods: Consecutive patients with stages I-IIIc endometrial cancer treated between 2008 and 2014 in our department with post-operative 3DCRT or IMRT WPRT were studied retrospectively. Patients with cervical involvement underwent additional low-dose rate vaginal brachytherapy. The impact of the WPRT technique on local control, tolerance, disease-free survival (DFS) and overall survival (OS) was assessed. Clinicians evaluated routinely acute radiation toxicity each week during radiation therapy and late toxicity during standard follow-up consultations. Results: Median follow-up was 50 months (range: 6-158). Among the 83 patients included, 47 were treated with 3DCRT and 36 with IMRT. There was no difference in patient characteristics between groups. The 5-year locoregional control and DFS rates were 94.5% and 68%, respectively. No significant difference was found between the 3DCRT and IMRT groups in terms of survival, with 5-year OS rates of 74.6% and 78%, respectively. In multivariate analysis, age over 68, stage > T1 and grade 3 were independently associated with shorter DFS and OS. Seven patients (8.4%) had grades 3-4 acute gastrointestinal (GI) toxicity with five patients (10.6%) and two (5.4%) in the 3DCRT and IMRT groups, respectively (p = .69). One case (1.2%) of late grade 3 GI toxicity was observed treated in 3DCRT. Conclusions: IMRT seems to be a safe technique for the treatment of endometrial cancer with a trend towards decreased acute GI toxicities. Results of the phase 3 RTOG 1203 trial are needed to confirm these results.

Frozen Section for Detection of Lymph Nodes After Cervical Injection with Indocyanine Green (ICG) for Sentinel Lymph Node Technique in Endometrial Cancer Staging

OBJECTIVE

The aim of this study was to assess the role of frozen section (FS) in identifying an absence of lymph nodes during sentinel lymph node (SLN) biopsy for apparent early-stage endometrial cancer (EC).

METHODS

Consecutive apparent early-stage EC patients who had SLNs removed after cervical injection with indocyanine green (ICG) from 1 June 2014 to 30 June 2016 were analyzed. An empty node (EN) was defined as an SLN specimen without evidence of lymph node(s). The association of tumor and patient characteristics with an EN was evaluated, and trend analysis to compare the rate of ENs over calendar quarters was performed. A decision-tree model was then created to compare the use of FS versus no FS for SLN evaluation in the hypothetical cohort affected by early-stage EC in the US each year.

RESULTS

Over the study period, 300 patients met the inclusion criteria. FS revealed ENs in 24 (8%) patients. No association between patient demographic characteristics (age, body mass index, prior abdominopelvic surgery, international federation of gynecology and obstetrics (FIGO) stage, histology, myometrial invasion, cervical stromal invasion) and presence of ENs was observed. The rate of ENs at FS did not change over time (p = 0.68). The hypothetical analysis showed a 4.3% decrease of inappropriately staged patients with the use of FS on the SLN (95% confidence interval 4.1-4.5).

CONCLUSIONS

ENs during SLN biopsy for EC staging is not a rare event and can be easily detected with FS. The implementation of FS of SLN might reduce inadequate staging of EC. Individual institutions may want to examine their own EN rates and determine if this would assist them in their SLN practices for EC.

[Doses to organs at risk for conformational and stereotactic radiotherapy: Bladder]

Bladder dose constraints in case of conformational radiotherapy/intensity-modulated radiotherapy and stereotactic radiotherapy are reported from the literature, in particular from the French radiotherapy society RECORAD recommendations, according to the treated pelvic tumor sites. The dose-volume effect on urinary toxicity is not clearly demonstrated, making difficult to establish absolute dose constraints for the bladder. In case of high-dose prostate cancer radiotherapy, the bladder dose constraints are: V60Gy<50% and maximum dose<80Gy for standard fractionation and V60Gy<5%, V48Gy<25% and V41Gy<50% for moderate hypofractionation (20 fractions of 3Gy). In case of prostate stereotactic radiotherapy (five fractions of 7.25Gy), the most frequent dose constraints in the literature are V37Gy<10cm³ and V18Gy<40%. In case of conformational radiotherapy of cervix cancer, postoperative endometrium, anal canal and rectum, the recommendations are V40Gy<40% and D2% lower than the prescribed dose.

The prognostic value of D-dimer levels in endometrial cancer patients treated with intensity-modulated radiation therapy

Explain the important role of plasma D-dimer in cancers. Plasma D-dimer is increased in various tumors. However, the predictive value of plasma D-dimer is unclear. This study is aimed to evaluate the prognostic value of the D-dimer level in patients managed with intensity-modulated radiation for endometrial cancer. The D-dimer levels of forty patients with endometrial cancer were assessed before (D1) and after (D2) intensity-modulated radiation therapy (IMRT), respectively. The D-dimer level changes (ΔD) were defined as D2 minus D1. Cox regression and log-rank tests were used to evaluate the D-dimer levels in relation to progression free survival (PFS) and overall survival (OS). The OS and PFS of patients with a low D1 were significantly longer than those with a high D1 (P< 0.001, P< 0.001). We saw the similar correlation between D2, PFS and OS (P< 0.001, P< 0.001). Multivariate survival analyses showed that D-dimer was independently associated with OS and PFS in patients with endometrial cancer. The ΔD level was not related to the OS and PFS in endometrial cancer patients. The levels of D-dimer may be considered as an important predictor of PFS and OS in endometrial cancer patients treated with IMRT.

Impact of postoperative intensity-modulated radiation therapy (IMRT) on the rate of bowel obstruction in gynecologic malignancy

OBJECTIVE

The purpose was to determine the potential impact of IMRT on the rate of bowel obstruction (BO), in patients with gynecologic malignancies undergoing postoperative pelvic RT.

METHODS

We performed a retrospective review of all patients with endometrial or cervical cancer who received postoperative pelvic RT at our institution from 2000 to 2012. Patients who received definitive or palliative RT, or those with BO due to disease progression, were excluded. Standard two-sided statistical tests were used to evaluate for associated risk factors. Kaplan-Meier, Log rank and Cox proportional hazards regression analysis tests were performed for actuarial analysis.

RESULTS

A total of 224 patients were identified, 120 (54%) received postoperative pelvic IMRT and 104 (46%) 3-dimentional (3-D) RT. Median follow-up time was 67months. BO was grade 1 (asymptomatic) in 2/228 (0.9%), grade 2 (conservative management) in 4 (1.8%), and grade 3≥ in 4 (1.8%). Overall, the 5-year actuarial rate of BO was 4.8%. The 5-year rate of BO in the IMRT group was 0.9% compared to 9.3% for 3-D RT (p=0.006). Patients with BMI≥30kg/m(2) were less likely to develop BO (2.6% vs. 8.3; p=0.03). On multivariate analysis, only IMRT retained its significance as an independent predictor of less BO (p=0.022).

CONCLUSIONS

The use of postoperative IMRT for cervical and endometrial cancer was associated with significant reduction in the rate of bowel obstruction. This difference maintained its statistical significance on multivariate analysis. Such finding if confirmed by others will help further solidify the benefit of IMRT in gynecologic cancers.