Survival and Control Prognosticators of Recurrent Gynecological Malignancies of the Pelvis and Para-aortic Region Treated with Stereotactic Body Radiation Therapy

Stereotactic Body Radiation Therapy for Gynecologic Malignancies: A Case-Based Radiosurgery Society Practice Review

PURPOSE

The use of stereotactic body radiation therapy (SBRT) for gynecologic malignancies is controversial. We discuss certain circumstances when highly precise SBRT may be a useful tool to consider in the management of selected patients.

METHODS AND MATERIALS

Case selection included the following scenarios, the first 2 with palliative intent, para-aortic nodal oligorecurrence of ovarian cancer, pelvic sidewall oligorecurrence of cervical cancer, and inoperable endometrial cancer boost after intensity modulated radiation to the pelvis treated with curative intent. Patient characteristics, fractionation, prescription dose, treatment technique, and dose constraints were discussed. Relevant literature to these cases was summarized to provide a framework for treatment of similar patients.

RESULTS

Treatment of gynecologic malignancies with SBRT requires many considerations, including treatment intent, optimal patient selection, fractionation selection, tumor localization, and plan optimization. Although other treatment paradigms including conventionally fractionated radiation therapy and brachytherapy remain the standard-of-care for definitive treatment of gynecologic malignancies, SBRT may have a role in palliative cases or those where high doses are not required due to the unacceptable toxicity that may occur with SBRT.

CONCLUSIONS

A case-based practice review was developed by the Radiosurgery Society to provide a practical guide to the common scenarios noted above affecting patients with gynecologic malignancies.

Online Adaptive Magnetic Resonance-guided Radiation Therapy for Gynaecological Cancers: Preliminary Results of Feasibility and Outcome

AIMS

To present the preliminary results on the clinical utilisation of an online daily adaptive magnetic resonance-guided radiation therapy (MRgRT) for various gynaecological cancers.

MATERIALS AND METHODS

Twelve patients treated between September 2018 and June 2022 were included. Six patients (50%) were treated with pelvic radiation therapy followed by MRgRT boost as brachytherapy boost was ineligible or unavailable, three patients (25%) were treated with pelvic MRgRT followed by high dose rate brachytherapy, two patients (16.7%) were treated with only MRgRT, one patient (8.3%) was treated with linear accelerator-based radiation therapy followed by MRgRT boost for bulky iliac lymph nodes.

RESULTS

The median age was 56.5 years (range 31-86 years). Eight patients (66.7%) had a complete response, three patients (25%) had a partial response and one patient (8.3%) died due to acute renal failure. The mean follow-up time was 11.2 months (range 3.1-42.6 months). The estimated 1-year overall survival was 88.9%. The median treatment time was 47 days (range 10-87 days). During external beam radiation therapy, 10 (83.3%) patients had concomitant chemoradiotherapy. Pelvic external beam radiation therapy doses for all cohorts were 45-50.4 Gy with a fraction dose of 1.8 Gy. The median magnetic resonance-guided boost dose was 32 Gy (range 20-50 Gy) and fraction doses ranged between 4 and 10 Gy. Three patients were treated with intracavitary high dose rate brachytherapy (26-28 Gy in four to five fractions). None of the patients had grade >3 late genitourinary toxicities.

CONCLUSION

MRgRT is reliable and clinically feasible for treating patients with gynaecological cancers alone or in combination with brachytherapy with an acceptable toxicity and outcome. MRgRT boost could be an option when brachytherapy is not available or ineligible.

Stereotactic Body Reirradiation in Gynaecological Cancer: Outcomes and Toxicities from a Single Institution Experience

AIMS

To report toxicity profile, outcomes and quality of life (QoL) data in patients with recurrent gynaecological cancer who underwent stereotactic body radiotherapy (SBRT) retreatment.

MATERIALS AND METHODS

Data from patients' folders were retrospectively extracted, focusing on the primary neoplasm, previous systemic therapies and previous radiotherapy. Concerning SBRT, the total dose (five daily fractions) was delivered with a linear accelerator using intensity-modulated radiotherapy techniques. Acute and late toxicities were assessed by the CTCAE 4.03 scale. QoL was evaluated according to the Cancer Linear Analogue Scale [CLAS1 (fatigue), CLAS2 (energy level), CLAS3 (daily activities)].

RESULTS

Between December 2005 and August 2021, 23 patients (median age 71 years, range 48-80) with 27 lesions were treated. Most patients had endometrial (34.8%), ovarian (26.1%) and cervical cancer (26.1%) as the primary tumour. The most common SBRT schedules in five fractions were 30 Gy (33.3%), 35 Gy (29.6%) and 40 Gy (29.6%). The median follow-up was 32 months (range 3-128). There were no patients reporting acute or late toxicities higher than grade 2, except for a bone fracture. One- and 2-year local control was 77.9% and 70.8%, respectively. One- and 2-year overall survival was 82.6% and 75.1%, respectively. The overall response rate was 96.0%. Regarding QoL, no statistically significant difference was identified between the baseline and follow-up values: the median CLAS1, CLAS2 and CLAS3 scores for each category were 6 (range 4-10) at baseline and 6 (range 3-10) 1 month after SBRT.

CONCLUSIONS

This preliminary experience suggests that SBRT retreatment for recurrent gynaecological cancer is a highly feasible and safe treatment with limited side-effects and no short-term QoL impairment.

Clinical Outcomes of Stereotactic Body Radiotherapy (SBRT) for Oligometastatic Patients with Lymph Node Metastases from Gynecological Cancers

BACKGROUND

To evaluate clinical outcomes of stereotactic body radiation therapy (SBRT) as a local treatment for lymph node metastases from gynecological cancers.

METHODS

Between November 2007 and October 2021, we retrospectively analyzed 29 lymph node metastases in 22 oligometastatic/oligoprogressive patients treated with SBRT. The Kaplan-Meier method was used to estimate the rates survival. Univariate analysis for prognostic factors were performed with the log-rank test, and Cox proportional hazards regression was used to estimate hazard ratios (HR).

RESULTS

Median age was 62 years (IQR, 50-80 years). Median follow-up was 17 months (IQR 10.5-31 months). The median survival was 22 months (CI 95%: 4.2-39.7, IQR: 12.5-34.5 months). Six months, one year and two year overall survival (OS) were 96.6%, 85.2%, and 48.7%, respectively. Median local control (LC) was not reached. Six months, 1one year and 2 year were 93.1%, 87.9%, and 79.9%, respectively. Distant metastasis free survival (DMFS) at one year, and two year was 53% and 37.1%, respectively Four patients (18%) experienced acute G1-G2 toxicities. No G3-4 acute toxicity was reported, and no late toxicity was observed.

CONCLUSIONS

SBRT for lymph node recurrence offers excellent in-field tumor control with safe profile and low toxicities. Size, number of oligometastases, and time primary tumor to RT seem to be significant prognostic factors.

Re-Irradiation for Recurrent Cervical Cancer: A State-of-the-Art Review

The recurrence rate of cervical cancer after primary treatment can reach 60%, and a poor prognosis is reported in most cases. Treatment options for the recurrence of cervical cancer mainly depend on the prior treatment regimen and the location of recurrent lesions. Re-irradiation is still considered as a clinical challenge, owing to a high incidence of toxicity, especially in in-field recurrence within a short period of time. Recent advances in radiotherapy have preliminarily revealed encouraging outcomes of re-irradiation. Several centers have concentrasted on stereotactic body radiation therapy (SBRT) for the treatment of well-selected cases. Meanwhile, as the image-guiding techniques become more precise, a better dose profile can also be achieved in brachytherapy, including high-dose-rate interstitial brachytherapy (HDR-ISBT) and permanent radioactive seed implantation (PRSI). These treatment modalities have shown promising efficacy with a tolerable toxicity, providing further treatment options for recurrent cervical cancer. However, it is highly unlikely to draw a definite conclusion from all of those studies due to the large heterogeneity among them and the lack of large-scale prospective studies. This study mainly reviews and summarizes the progress of re-irradiation for recurrent cervical cancer in recent years, in order to provide potential treatment regimens for the management of re-irradiation.

CyberKnife Stereotactic Ablative Radiotherapy for Recurrent or Oligometastatic Gynecological Cancers

Purpose Use of stereotactic ablative radiotherapy (SABR) in the treatment of recurrent or metastatic lesions from a primary gynecologic cancer is a relatively new concept. The present study aims to assess the safety, efficacy, and possible toxicity profile of CyberKnife SABR, recurrent or metastatic disease. Materials/Methods CyberKnife VSI-based SABR was offered to 20 oligometastatic/recurrent gynecological cancer patients between 2013 and 2019. Patient, tumor, and treatment characteristics including radiotherapy details, clinical outcome in terms of local control rates, and toxicities are reported in this study. Results Twenty-five recurrent or oligometastatic lesions for 20 primary gynecologic cancer patients including cervical ( n = 8), ovarian ( n = 6), endometrial ( n = 5), and vulvar ( n = 1) cancers were analyzed. Of these, 4 (16%) were intracranial lesions and remaining 21 (84%) were extracranial, consisting of 14 (67%) extrapelvic and 7 (33%) pelvic lesions. The median SABR dose delivered was 60 Gy biologically effective dose (range 42-133 Gy) in an average of four fractions (range 1-6). The mean follow-up was 18 (range 2-70) months. Local tumor control was achieved in 82% of patients. There was no grade ≥ 3 toxicity recorded. Conclusion Our study results suggest that CyberKnife SABR is an effective treatment modality with no major morbidity in patients with recurrent or oligometastatic gynecological cancers.

Phase I Trial of Stereotactic MRI-Guided Online Adaptive Radiation Therapy (SMART) for the Treatment of Oligometastatic Ovarian Cancer

PURPOSE

Stereotactic body radiation therapy is increasingly used to treat a variety of oligometastatic histologies, but few data exist for ovarian cancer. Ablative stereotactic body radiation therapy dosing is challenging in sites like the abdomen, pelvis, and central thorax due to proximity and motion of organs at risk. A novel radiation delivery method, stereotactic magnetic-resonance-guided online-adaptive radiation therapy (SMART), may improve the therapeutic index of stereotactic body radiation therapy through enhanced soft-tissue visualization, real-time nonionizing imaging, and ability to adapt to the anatomy-of-the-day, with the goal of producing systemic-therapy-free intervals. This phase I trial assessed feasibility, safety, and dosimetric advantage of SMART to treat ovarian oligometastases.

METHODS AND MATERIALS

Ten patients with recurrent oligometastatic ovarian cancer underwent SMART for oligometastasis ablation. Initial plans prescribed 35 Gy/5 fractions with goal 95% planning target volume coverage by 95% of prescription, with dose escalation permitted, subject to strict organ-at-risk dose constraints. Daily adaptive planning was used to protect organs-at-risk and/or increase target dose. Feasibility (successful delivery of >80% of fractions in the first on-table attempt) and safety of this approach was evaluated, in addition to efficacy, survival metrics, quality-of-life, prospective timing and dosimetric outcomes.

RESULTS

Ten women with seventeen ovarian oligometastases were treated with SMART, and 100% of treatment fractions were successfully delivered. Online adaptive plans were selected at time of treatment for 58% of fractions, due to initial plan violation of organs-at-risk constraints (84% of adapted fractions) or observed opportunity for planning target volume dose escalation (16% of adapted fractions), with a median on-table time of 64 minutes. A single Grade ≥3 acute (within 6 months of SMART) treatment-related toxicity (duodenal ulcer) was observed. Local control at 3 months was 94%; median progression-free survival was 10.9 months. Median Kaplan-Meier estimated systemic-therapy-free survival after radiation completion was 11.5 months, with concomitant quality-of-life improvements.

CONCLUSIONS

SMART is feasible and safe for high-dose radiation therapy ablation of ovarian oligometastases of the abdomen, pelvis, and central thorax with minimal toxicity, high rates of local control, and prolonged systemic-therapy-free survival translating into improved quality-of-life.

Online Magnetic Resonance-Guided Radiotherapy (oMRgRT) for Gynecological Cancers

Radiation therapy (RT) is increasingly being used in gynecological cancer management. RT delivered with curative or palliative intent can be administered alone or combined with chemotherapy or surgery. Advanced treatment planning and delivery techniques such as intensity-modulated radiation therapy, including volumetric modulated arc therapy, and image-guided adaptive brachytherapy allow for highly conformal radiation dose delivery leading to improved tumor control rates and less treatment toxicity. Quality on-board imaging that provides accurate visualization of target and surrounding organs at risk is a critical feature of these advanced techniques. As soft tissue contrast resolution is superior with magnetic resonance imaging (MRI) compared to other imaging modalities, MRI has been used increasingly to delineate tumor from adjacent soft tissues and organs at risk from initial diagnosis to tumor response evaluation. Gynecological cancers often have poor contrast resolution compared to the surrounding tissues on computed tomography scan, and consequently the benefit of MRI is high. One example is in management of locally advanced cervix cancer where adaptive MRI guidance has been broadly implemented for adaptive brachytherapy. The role of MRI for external beam RT is also steadily increasing. MRI information is being used for treatment planning, predicting, and monitoring position shifts and accounting for tissue deformation and target regression during treatment. The recent clinical introduction of online MRI-guided radiation therapy (oMRgRT) could be the next step in high-precision RT. This technology provides a tool to take full advantage of MRI not only at the time of initial treatment planning but as well as for daily position verification and online plan adaptation. Cervical, endometrial, vaginal, and oligometastatic ovarian cancers are being treated on MRI linear accelerator systems throughout the world. This review summarizes the current state, early experience, ongoing trials, and future directions of oMRgRT in the management of gynecological cancers.

An Inter-observer Study to Determine Radiotherapy Planning Target Volumes for Recurrent Gynaecological Cancer Comparing Magnetic Resonance Imaging Only With Computed Tomography-Magnetic Resonance Imaging

AIMS

Target delineation uncertainty is arguably the largest source of geometric uncertainty in radiotherapy. Several factors can affect it, including the imaging modality used for delineation. It is accounted for by applying safety margins to the target to produce a planning target volume (PTV), to which treatments are designed. To determine the margin, the delineation uncertainty is measured as the delineation error, and then a margin recipe used. However, there is no published evidence of such analysis for recurrent gynaecological cancers (RGC). The aims of this study were first to quantify the delineation uncertainty for RGC gross tumour volumes (GTVs) and to calculate the associated PTV margins and then to quantify the difference in GTV, delineation uncertainty and PTV margin, between a computed tomography-magnetic resonance imaging (CT-MRI) and MRI workflow.

MATERIALS AND METHODS

Seven clinicians delineated the GTV for 20 RGC tumours on co-registered CT and MRI datasets (CT-MRI) and on MRI alone. The delineation error, the standard deviation of distances from each clinician's outline to a reference, was measured and the required PTV margin determined. Differences between using CT-MRI and MRI alone were assessed.

RESULTS

The overall delineation error and the resulting margin were 3.1 mm and 8.5 mm, respectively, for CT-MRI, reducing to 2.5 mm and 7.1 mm, respectively, for MRI alone. Delineation errors and therefore the theoretical margins, varied widely between patients. MRI tumour volumes were on average 15% smaller than CT-MRI tumour volumes.

DISCUSSION

This study is the first to quantify delineation error for RGC tumours and to calculate the corresponding PTV margin. The determined margins were larger than those reported in the literature for similar patients, bringing into question both current margins and margin calculation methods. The wide variation in delineation error between these patients suggests that applying a single population-based margin may result in PTVs that are suboptimal for many. Finally, the reduced tumour volumes and safety margins suggest that patients with RGC may benefit from an MRI-only treatment workflow.

CT-Guided Pelvic Lymph Nodal Brachytherapy

Purpose

This is a report of our initial experience using computed tomography (CT)-guided interstitial high dose rate (HDR) brachytherapy to treat bulky pelvic nodal metastases as a part of definitive radiotherapy.

Material and methods

Between February 2015 and April 2019, 14 cervical/endometrial cancer patients presenting with bulky pelvic node(s) underwent nodal interstitial brachytherapy boost in our institution. In total, 17 nodes were treated. The median maximum diameters of the positive nodes at the time of diagnosis and at the first nodal implant were 25 mm (range: 10-65 mm) and 16 mm (range: 9-51 mm), respectively. Dosimetry data of the lymph nodal target volume and small bowel were collected and compared using the paired-sample t-test. Treatment-related toxicities were classified using the Common Terminology Criteria for Adverse Events version 4.0.

Results

The median follow-up time for all patients was 26 months. Local recurrence in pelvic nodes occurred in one patient (7%) after 16 months. One patient experienced grade 3 bladder bleeding, and one patient experienced grade 2 pubic bone fracture. No patient had grade 2 or greater gastrointestinal toxicity. In the dosimetric analysis, the mean nodal brachytherapy D_90% in terms of the total equivalent dose of 2 Gy (EQD2) was 65.6 Gyαβ10. The mean small bowel dose (SBD)_0.1cc and SBD_1cc in terms of the total EQD2 were 60.4 and 56.5 Gyαβ3, respectively. Nodal D_90% was significantly higher in terms of the total EQD2 than the SBD_0.1cc (p = 0.003) and SBD_1cc (p < 0.001). The Kaplan-Meier 2-year pelvic control estimate was 90%.

Conclusions

CT-guided interstitial HDR pelvic nodal brachytherapy appears to be well tolerated with excellent local control in cervical or endometrial cancer patients with bulky pelvic nodes. This approach may offer a useful therapeutic option for unresected bulky pelvic nodes.

Stereotactic body radiation therapy (SBRT) in recurrent, persistent or oligometastatic gynecological cancers

OBJECTIVE

SBRT is a well-tolerated technique and provides local-regional control in a variety of metastatic and recurrent tumor types. The role of SBRT in extracranial recurrent, persistent, or oligometastatic gynecological tumors is not well-studied. We therefore retrospectively analyzed a sizeable number of patients in this setting.

METHODS

We performed a retrospective review of 86 patients with 209 tumors treated at our institution with SBRT for recurrent, persistent, or oligometastatic extracranial gynecological tumors. The median follow-up was 20 months (range 1-91). The median SBRT dose was 24 Gy (range 10-50) delivered in a median of 4 fractions (range 1-6). The Kaplan-Meier curves and log rank tests were used to assess local control (LC) and overall survival (OS). Cox proportional hazards model was used to evaluate for covariates associated with LC and OS.

RESULTS

The 1- and 3-year LC were 80% and 68% respectively. The 1- and 3-year OS were 70% and 39%. 32% of the lesions demonstrated complete response, 23% partial response and 20% stable disease. SBRT achieved better local control in smaller tumors. Toxicity was typically mild with grade 1 gastrointestinal toxicity and fatigue being the most common. Only 4.3% of treatments resulted in grade 2 or greater toxicity. There was only one case of grade 3 and no grade 4 or 5 toxicities.

CONCLUSIONS

SBRT offers a high rate of local control with low incidence of toxicity, mainly grade 1 GI toxicity and fatigue, and provides effective salvage therapy for oligometastatic extracranial pelvic and extra-pelvic gynecological tumors.

Stereotactic Body Radiation Therapy in Oligometastatic Uterine Cancer: Clinical Outcomes and Toxicity

We report on clinical outcomes in patients with oligometastatic uterine cancer treated with stereotactic body radiation therapy (SBRT). Twenty-seven patients with 61 lesions were treated with SBRT. Median follow-up was 16.9 months. Local control was achieved in 49/61 (80.3%) lesions. One-year local-progression-free survival and overall survival were 75.9% and 65.4%. Lesions with favorable response were smaller than lesions with unfavorable response (p = .007). Liver lesions were less likely to achieve favorable response (p = .0128). There were no grade 3 or 4 events. Treatment with SBRT can provide excellent local control in oligometastatic uterine cancer with minimal toxicity.

Stereotactic Ablative Radiotherapy for Recurrent or Metastatic Gynecological Cancer: Extending Lives?

OPINION STATEMENT

Recent phase II clinical trials suggest that stereotactic ablative radiation therapy (SABR) can potentially improve survival for patients with oligometastatic cancer. However, these studies have mostly enrolled primaries other than gynecologic malignancies. While level I evidence is limited, recent publications exploring the use of SABR for oligometastatic gynecologic cancers have indicated a potential role for this treatment in para-aortic lymph node recurrences, and in visceral and brain metastases. The use of SABR for recurrences in the pelvis presents a number of challenges as these patients have often received previous radiation treatment. In these settings, care must be taken to avoid trespassing normal tissue tolerance with SABR leading to toxicity, especially as the potential benefit of SABR in this setting is not based on high-level evidence. Although SABR is feasible and in general safe for oligometastatic gynecologic malignancies, insufficient data are available to indicate whether it is associated with improved survival. Clinical judgment that incorporates patient and tumor factors is needed to determine if SABR is appropriate for selecting patients. Future directions include combining SABR with novel systemic therapies, determining optimal sequencing of treatments, and generating more robust randomized data pertaining to the use of SABR for oligometastatic gynecologic cancers.

Survey of current practices from an international task force for gynecological stereotactic ablative radiotherapy

Background

Stereotactic Ablative Radiotherapy (SABR) is an effective treatment that improves local control for many tumours. However, the role of SABR in gynecological cancers (GYN) has not been well-established. We hypothesize that there exists considerable variation in GYN-SABR practice and technique. The goal of this study is to describe clinical and technical factors in utilization of GYN-SABR among 11 experienced radiation oncologists.

Materials and methods

A 63 question survey on GYN-SABR was sent to 11 radiation oncologists (5 countries) who have published original research, conducted trials or have an established program at their institutions. Responses were combined and analyzed at a central institution.

Results

Most respondents indicated that salvage therapy (non-irradiated or re-irradiated field) for nodal (81%) and primary recurrent disease (91%) could be considered standard options for SABR in the setting of inability to administer brachytherapy. All other indications should be considered on clinical trials. Most would not offer SABR as a boost in primary treatment off-trial without absolute contraindications to brachytherapy. Multi-modality imaging is often (91%) used for planning including PET, CT contrast and MRI. There is a wide variation for OAR tolerances however small bowel is considered the dose-limiting structure for most experts (91%). Fractionation schedules range from 3 to 6 fractions for nodal/primary definitive and boost SABR.

Conclusions

Although SABR has become increasingly standard in other oncology disease sites, there remains a wide variation in both clinical and technical factors when treating GYN cancers. Nodal and recurrent disease is considered a potential indication for SABR whereas other indications should be offered on clinical trials. This study summarizes SABR practices among GYN radiation oncologists while further studies are needed to establish consensus guidelines for GYN-SABR treatment.

American Brachytherapy Society working group report on the patterns of care and a literature review of reirradiation for gynecologic cancers

PURPOSE

Recurrences of previously irradiated gynecological malignancies are uncommon. Standardized management of these cases is not well established. We aim to provide an in-depth literature review and present current practice patterns among an international group of experienced practitioners in the reirradiation setting of gynecologic cancers.

METHODS AND MATERIALS

An extensive literature search was performed and 35 articles were selected based on preset criteria. A 20-question online survey of 10 experts regarding their retreatment practices was also conducted.

RESULTS

The reviewed publications include a diverse group of patients, multiple treatment techniques, a range of total doses, local control, overall survival, and toxicity outcomes. Overall, local control ranged from 44% to 88% over 1-5 years with OS in the range of 39.5-82% at 2-5 years. Late G3-4 toxicity varied very broadly from 0% to 42.9%, with most papers reporting serious toxicities greater than 15%. The most common reirradiation technique utilized was brachytherapy. Some low-dose-rate data suggest improved outcomes with doses >50 Gy. The high-dose-rate data are more varied with some studies suggesting improved local control with doses >40 Gy. In general, a longer time interval between the first and second course of radiation as well as recurrences <2-4 cm tend to have improved outcomes.

CONCLUSIONS

Reirradiation with brachytherapy results in relatively reasonable local control and toxicities for women with recurrent gynecologic cancers. The appropriate dose for each case needs to be individualized given the heterogeneity of cases. Multidisciplinary management is critical to develop individualized plans and to clearly communicate potential side effects and expected treatment outcomes.

TAKE HOME MESSAGE

Reirradiation with brachytherapy is an acceptable effective organ preserving approach for recurrent gynecologic cancers with a reasonable local control and toxicity profile. Each case requires multidisciplinary management to develop an individualized approach. Monitoring for potential long-term toxicities is essential.

Management Strategies for Recurrent Endometrial Cancer

INTRODUCTION

Endometrial cancer is the most common gynecologic malignancy in the developed world, and its incidence is increasing. Mortality from this cancer has not improved in recent decades and is primarily driven by high-grade carcinomas that are more likely to present at an advanced stage and ultimately are more likely to recur. The prognosis for recurrent endometrial cancer is poor, especially for the 50% of these women that present with extrapelvic disease recurrence. As a standard of care, recurrent disease has been treated with platinum-based chemotherapy; however, new therapies are emerging as we identify drivers of proliferation and metastasis at the cellular and molecular levels. Areas Covered: We review currently available data for the management of recurrent endometrial cancer, with a focus on systemic treatment of recurrent disease. We discuss the available evidence for first-line, second-line, and subsequent systemic therapy and discuss emerging therapeutic targets including their biologic plausibility and early clinical data. Expert Commentary: Endometrial cancer, though prevalent, remains underfunded and understudied. Recurrent and metastatic disease remains difficult to treat, and prospective randomized data are limited. Our ability to reduce mortality due to this cancer is dependent on identifying new and effective therapeutic strategies for recurrent disease.

Stereotactic Radiotherapy for Oligometastases in Lymph Nodes-A Review

In recent years, the concept of oligometastases has become accepted and reports on stereotactic body radiotherapy as a treatment method have been published. Lesions in the brain, lung, and liver have been reported as target lesions. However, lymph node oligometastases could be a good candidate for stereotactic body radiotherapy as well. In this study, the usability of stereotactic body radiotherapy for oligometastases to lymph nodes is assessed by researching for each primary site. As a result, we could consider that stereotactic body radiotherapy could be almost well applied for lymph node oligometastases from the breast, gynecological organs, and prostate. However, doubts remain concerning the usefulness of stereotactic body radiotherapy for cervical node metastases from head and neck cancer or for mediastinal node metastases from lung or esophageal cancer since late toxicities have occurred with a large radiation dose at hypofractionation to major vessels or the central respiratory tract, especially in patients with irradiation histories. In addition, high-dose irradiation is required to control lymph node metastases from colorectal cancer due to its radioresistance, and severe late adverse events would therefore occur in adjacent organs such as the gastrointestinal tract. In cases of lymph node oligometastases with a primary tumor in the stomach or esophagus, stereotactic body radiotherapy should be used limitedly at present because this patient population is not so large and these metastases are often located close to organs at risk. Because of the varied status of recurrence and varied conditions of patients, it is difficult to determine the optimal dose for tumor control. It might be reasonable to determine the treatment dose individually based on dose constraints of adjacent organs. The oligometastatic state is becoming more frequently identified with more sensitive methods of detecting such oligometastases. In addition, there seems to be another type of oligometastases, so-called induced oligometastases, following successful systemic treatment. To determine the optimal indication of stereotactic body radiotherapy for lymph node oligometastases, further investigation about the mechanisms of oligometastases and further clinical studies including a phase III study are needed.

CyberKnife Stereotactic Radiosurgery for Primary and Metastatic Cancer in the Cervix

Standard radiation therapy for cervical cancer consists of external beam radiation therapy followed by an intracavitary brachytherapy boost. When brachytherapy cannot be performed due to unfavorable anatomy or coexisting medical conditions, stereotactic body radiotherapy with the CyberKnife is another treatment option which is less invasive and can be performed in a shorter treatment time. We performed non-invasive therapy using the CyberKnife for five cases of urogenital cancer located in the cervix. The local tumor control was excellent with minimal toxicity. Non-invasive treatment was demonstrated as feasible with the CyberKnife for contraindication of surgery or brachytherapy.

Re-irradiation of cervical and endometrial cancer

PURPOSE OF REVIEW

Re-irradiation historically has been associated with unacceptable toxicity and limited benefit. Recent advances in radiotherapy can change the treatment paradigm to provide new salvage treatments for recurrences of cervical and endometrial cancer.

RECENT FINDINGS

Image-guided brachytherapy is an effective method for salvaging central pelvic recurrence, although it has resulted in 20-25% severe late toxicity. Pelvic sidewall disease is not accessible to brachytherapy, so a combined modality approach with radical surgery and intraoperative radiotherapy is an alternative approach. Stereotactic body radiotherapy (SBRT) now provides the option of radical re-irradiation with local control rates of 50-80% and a low incidence of severe late complications.

SUMMARY

Initial outcomes using SBRT and image-guided brachytherapy for re-irradiation of gynaecological cancer are encouraging. There has been good local control and acceptable toxicity. Further, large-scale studies are required to define optimal target doses and OAR limits.

Malignant Brenner tumor of the ovary: Review and case report

Ovarian neoplasms are a heterogeneous group of tumors with varying incidence in the general population. The most common are the surface epithelial tumors which include transitional cell tumors. Transitional cell tumors include both transitional cell carcinoma and Brenner tumor. The vast majority of Brenner tumors are benign, often incidental findings; however, malignant Brenner tumors (MBT) do occasionally occur. MBT present similarly to other ovarian neoplasms with abdominal pain and bulk symptoms. On imaging, these tumors demonstrate nonspecific findings. Microscopically, they demonstrate areas of conventional benign Brenner tumor juxtaposed with regions of frank malignancy showing marked cytologic atypia and infiltration. There is no consistent tumor marker for these tumors, but CA-125, CA 72-4 and SCC have been reported in singular instances. Tumors express several immunohistochemical markers of urothelial differentiation including uroplakin III, thrombomodulin, GATA3, p63, as well as cytokeratin 7. The primary treatment modality is surgical excision. Due to their rarity, the precise role and regimen of adjuvant chemo-radiation therapy for MBT has not been established. We herein review a case of MBT with emphasis on primary treatment and treatment of recurrent disease, including the use of adjuvant pelvic radiation, discuss the current state of the literature and standards of practice regarding this malignancy.

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Histologic differentiation of MBT from TCC is critical for diagnosis.

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Surgical staging should be performed for all cases of MBT.

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The role of adjuvant strategies for MBT is poorly defined.