Adjuvant brachytherapy for FIGO stage I serous or clear cell endometrial cancer

Objectives

Optimal adjuvant treatment for early-stage clear cell and serous endometrial cancer remains unclear. We report outcomes for women with surgically staged International Federation of Gynecology and Obstetrics (FIGO) stage I clear cell, serous, and mixed endometrial cancers following adjuvant vaginal cuff brachytherapy with or without chemotherapy.

Methods

From April 1998 to January 2020, women with FIGO stage IA–IB clear cell, serous, and mixed endometrial cancer underwent surgery and adjuvant vaginal cuff brachytherapy. Seventy-six patients received chemotherapy. High-dose rate vaginal cuff brachytherapy was planned to a total dose of 21 gray in three fractions using a multichannel vaginal cylinder. The primary objective was to determine the effectiveness of adjuvant vaginal cuff brachytherapy and to identify surgicopathological risk factors that could portend towards worse oncological outcomes.

Results

A total of 182 patients were included in the analysis. Median follow-up was 5.3 years (2.3–12.2). Ten-year survival was 73.3%. Five-year cumulative incidence (CI) of vaginal, pelvic, and para-aortic relapse was 1.4%, 2.1%, and 0.9%, respectively. Five-year locoregional failure, any recurrence, peritoneal relapse, and other distant recurrence was 4.4%, 11.6%, 5.3%, and 6.7%, respectively. On univariate analysis, locoregional failure was worse for larger tumors (per 1 cm) (HR 1.9, 95% CI 1.2 to 3.0, p≤0.01). Any recurrence was worse for tumors of at least 3.5 cm (HR 3.8, 95% CI 1.3 to 11.7, p=0.02) and patients with positive/suspicious cytology (HR 4.4, 95% CI 1.5 to 12.4, p≤0.01). Ten-year survival for tumors of at least 3.5 cm was 56.9% versus 86.6% for those with smaller tumors (HR 2.9, 95% CI 1.4 to 5.8, p≤0.01). Ten-year survival for positive/suspicious cytology was 50.9% versus 77.4% (HR 2.2, 95% CI 0.9 to 5.4, p=0.09). Multivariate modeling demonstrated worse locoregional failure, any recurrence, and survival with larger tumors, as well as any recurrence with positive/suspicious cytology. Subgroup analysis demonstrated improved outcomes with the use of adjuvant chemotherapy in patients with large tumors or positive/suspicious cytology.

Conclusion

Adjuvant vaginal cuff brachytherapy alone without chemotherapy is an appropriate treatment for women with negative peritoneal cytology and small, early-stage clear cell, serous, and mixed endometrial cancer. Larger tumors or positive/suspicious cytology are at increased risk for relapse and worse survival, and should be considered for additional upfront adjuvant treatments, such as platinum-based chemotherapy.

Outcome of Soft-tissue Reconstruction in the Setting of Combined Preoperative and Intraoperative Radiotherapy for Extremity Soft-tissue Sarcomas

BACKGROUND/AIM

Reconstruction for soft-tissue sarcomas is complex and often uses soft-tissue flaps. To preserve critical structures, intraoperative radiotherapy (IORT) can be used to boost the total dose to these critical structures and close margins; however, there are limited data on the outcome of soft-tissue reconstruction in patients treated with IORT.

PATIENTS AND METHODS

Twenty patients received IORT with soft-tissue flap coverage. There were 14 tumors of the lower extremities and six of the upper, including seven free-flaps and 13 pedicle flaps. Mean preoperative and IORT doses were 49.4 Gy and 10.4 Gy, respectively, with a mean total dose of 59.8 Gy.

RESULTS

Seven (35%) patients had a complication, most commonly an infection (n=4, 27%). Total flap loss occurred in one treated with pedicle flap. Four (20%) patients suffered a radiation-associated fracture. At the final follow-up, the mean Musculoskeletal Tumor Society Score was 75±11%.

CONCLUSION

Complications and postoperative fractures were common with IORT, however, there were no cases requiring amputation.

A Prospective, Randomized, Double-blind, Placebo-controlled Study of Orbital Radiotherapy for Graves' Ophthalmopathy

CONTEXT

Although widely used for more than 85 years, the efficacy of radiotherapy for Graves' ophthalmopathy (GO) has not been established convincingly.

OBJECTIVE

To evaluate the efficacy of radiotherapy for GO.

DESIGN

Prospective, randomized, internally controlled, double-blind clinical trial in a tertiary care academic medical center.

PARTICIPANTS

The patients were ethnically diverse males and females over age 30 seen in a referral practice. The patients had moderate, symptomatic Graves' ophthalmopathy (mean clinical activity score, 6.2) but no optic neuropathy, diabetes, recent steroid treatment, previous decompression, or muscle surgery. Forty-two of 53 consecutive patients were enrolled after giving informed consent and fulfilling study entry criteria. Eleven eligible patients declined to participate because of inconvenience, desire for alternative therapy, or concern about radiation.

INTERVENTION

One randomly selected orbit was treated with 20 Gy of external beam therapy; sham therapy was given to the other side. Six months later, the therapies were reversed.

MAIN OUTCOME MEASURES

Every 3 months for 1 year, we measured the volume of extraocular muscle and fat, proptosis, range of extraocular muscle motion, area of diplopia fields, and lid fissure width. Effective treatment for GO will modify one or more of these parameters.

RESULTS

No clinically or statistically significant difference between the treated and untreated orbit was observed in any of the main outcome measures at 6 months. At 12 months, muscle volume and proptosis improved slightly more in the orbit that was treated first.

CONCLUSIONS

In this group of patients, representative of those for whom radiotherapy is frequently recommended, we were unable to demonstrate any beneficial therapeutic effect. The slight improvement noted in both orbits at 12 months may be the result of natural remission or of radiotherapy, but the changes are of marginal clinical significance.

NCCN Guidelines Insights: Soft Tissue Sarcoma, Version 1.2021

The NCCN Guidelines for Soft Tissue Sarcoma provide recommendations for the diagnosis, evaluation, treatment, and follow-up for patients with soft tissue sarcomas. These NCCN Guidelines Insights summarize the panel discussion behind recent important updates to the guidelines, including the development of a separate and distinct guideline for gastrointestinal stromal tumors (GISTs); reconception of the management of desmoid tumors; inclusion of further recommendations for the diagnosis and management of extremity/body wall, head/neck sarcomas, and retroperitoneal sarcomas; modification and addition of systemic therapy regimens for sarcoma subtypes; and revision of the principles of radiation therapy for soft tissue sarcomas.

EyeDose: An open-source tool for using published Monte Carlo results to estimate the radiation dose delivered to the tumor and critical ocular structures for 125I Collaborative Ocular Melanoma Study eye plaques

PURPOSE

Radiation side effects and visual outcome for uveal melanoma patients managed with plaque radiotherapy are dependent on the radiation dose administered to the tumor and nearby healthy tissues. We have developed an open-source software tool, EyeDose, to simplify and standardize tumor and critical structure dose reporting for Collaborative Ocular Melanoma Study eye plaques.

METHODS AND MATERIALS

EyeDose is a MATLAB-based program that calculates point dose and volume dose metrics for standard models of the tumor and critical ocular structures. It uses published three-dimensional dose distributions for eye plaques, calculated with Monte Carlo methods, which are oriented with respect to the eye using the tumor's position on a fundus diagram. A standard model for the ocular structures was created using published measurements and patient CT scans. EyeDose reports radiation statistics for the fovea, optic disc, lens, lacrimal gland, retina, and tumor. The dosimetric margin for implant placement uncertainty is also calculated.

RESULTS

EyeDose calculations were validated against previously published Monte Carlo results for eight different tumor positions, including the dose to the fovea, optic disc, lacrimal gland, lens, and along the central axis. EyeDose accepts a spreadsheet input for rapidly processing large retrospective patient data sets, with an average run time of <40 s per patient. EyeDose is published as an open-source tool for easy adaptation at different institutions.

CONCLUSIONS

EyeDose calculates radiation statistics for Collaborative Ocular Melanoma Study eye plaque patients with Monte Carlo accuracy and without a treatment planning system. EyeDose streamlines data collection for large retrospective studies and can also be used prospectively to assess plaque applicability.

VMAT Grid Therapy: A Widely Applicable Planning Approach

PURPOSE

To describe a novel and practical volumetric modulated arc therapy (VMAT) planning approach for grid therapy.

METHODS AND MATERIALS

Dose is prescribed to 1.5-cm diameter spherical contours placed throughout the gross tumor volume (GTV). Placement of spheres is variable, but they must maintain at least a 3-cm (center to center) separation, and the edge of any sphere must be at least 1 cm from any organ at risk (OAR). Three concentric ring structures are used during optimization to confine the highest doses to the center of the spheres and maximize dose sparing between them. The end result is alternating regions of high and low dose throughout the GTV and minimal dose to OARs. High-intensity flattening filter-free (FFF) modes are used to efficiently deliver the plans, and entire treatments typically take only 15 to 20 minutes.

RESULTS

The approach is illustrated with 2 examples treated at our institution. Patient #1 had a 1703-cm³ mediastinal mass and was prescribed 20 Gray (Gy) to 24 spherical regions within the GTV. Patient #2 had a 3680-cm³ abdominal tumor and was prescribed 18 Gy to 32 spherical regions within the GTV. Both patients received additional consolidative radiation approximately 1 week after the initial VMAT grid treatment. Each patient experienced marked reduction in tumor size and symptomatic relief without treatment-related complications.

CONCLUSIONS

We have described in detail a planning approach for VMAT grid therapy treatments that can typically be delivered in a clinically practical time span. The VMAT approach is especially useful for tumors that are surrounded by sensitive critical structures. As many centers offer VMAT treatments, the approach is widely accessible and can be readily implemented once appropriate patient selection and delivery processes are established.

Patient-reported functional outcomes in a cohort of hand and foot sarcoma survivors treated with limb sparing surgery and radiation therapy

BACKGROUND AND OBJECTIVES

Describe patient-reported functional outcomes for hand and foot sarcoma survivors treated with limb-sparing surgery and radiation therapy (LSS + RT).

METHODS

Fifty-four patients with hand/wrist and foot/ankle sarcomas treated with LSS + RT from 1991 to 2015 were identified. Survivors ≥18 years old without subsequent amputation completed self-assessed functional surveys: Toronto upper extremity salvage score (TESS-UE) and Michigan hand outcomes (MHQ) surveys for hand; TESS lower extremity (TESS-LE) and Foot and Ankle Outcomes (FAOS) surveys for foot. Scoring scales: 0-100, MHQ and TESS; -26 to 56 and 25-59, FAOS core and shoe comfort, respectively. Higher scores denote superior function.

RESULTS

Five-year local tumor control was 88%. Fourteen of 24 hand (58%) and 14/18 foot (78%) survivors completed surveys. Mean TESS-UE and MHQ scores were 89.4 and 72.8, respectively. Mean TESS-LE, core FAOS, and shoe comfort scores were 92.4, 46.19, and 53.1, respectively. No factors correlated with outcomes. TESS-UE and MHQ scores strongly correlated (r = .87). TESS-LE and FAOS scores were associated with a poor correlation (r = .02 and r = .69).

CONCLUSIONS

The largest patient-reported functional outcomes analysis for hand and foot sarcoma survivors treated with LSS + RT demonstrates excellent local tumor control and acceptable functional outcomes. Further exploration of optimal functional assessment tools is needed given the potential scope differences.

Role of adjuvant therapy in stage IIIC2 endometrial cancer

OBJECTIVE

The role of the different types of adjuvant treatments in endometrial cancer with para-aortic node metastases is unclear. The aim of this study was to report oncologic outcomes after adjuvant therapy in patients with stage IIIC2 endometrial cancer.

METHODS

This retrospective single-institution study assessed patients with stage IIIC2 endometrial cancer who underwent primary surgery from January 1984 to December 2014. All patients had hysterectomy (±salpingo-oophorectomy) plus lymphadenectomy (para-aortic nodes, ±pelvic nodes). We included all patients with stage III endometrial cancer and documented para-aortic lymph node metastases (International Federation of Obstetrics and Gynecologists stage IIIC2). We excluded patients who did not provide consent, who had synchronous cancer, or who underwent neoadjuvant chemotherapy. Follow-up was restricted to the first 5 years post-operatively. Cox proportional hazards models, with age as the time scale, was used to evaluate associations of risk factors with disease-free survival and overall survival.

RESULTS

Among 105 patients with documented adjuvant therapy, external beam radiotherapy was administered to 25 patients (24%), chemotherapy to 24 (23%), and a combination (chemotherapy and external beam radiotherapy) to 56 (53%) patients. Most patients receiving chemotherapy and external beam radiotherapy (80%) had chemotherapy first. The majority of relapses had a distant component (31/46, 67%) and only one patient had an isolated para-aortic recurrence. Non-endometrioid subtypes had poorer disease-free survival (HR 2.57; 95% CI 1.38 to 4.78) and poorer overall survival (HR 2.00; 95% CI 1.09 to 3.65) compared with endometrioid. Among patients with endometrioid histology (n=60), chemotherapy and external beam radiotherapy improved disease-free survival (HR 0.22; 95% CI 0.07 to 0.71) and overall survival (HR 0.28; 95% CI 0.09 to 0.89) compared with chemotherapy or external beam radiotherapy alone. Combination therapy did not improve prognosis for patients with non-endometrioid histology (n=45).

CONCLUSIONS

In our cohort of patients with stage IIIC2 endometrioid endometrial cancer, those receiving chemotherapy and external beam radiotherapy had improved survival compared with patients receiving chemotherapy or external beam radiotherapy alone. However, the prognosis of patients with non-endometrioid endometrial cancer remained poor, regardless of the adjuvant therapy administered. Distant recurrences were the most common sites of failure.

Radiotherapy Does Not Impact Long-term Function Following Resection of Soft-tissue Sarcomas of the Hand

BACKGROUND/AIM

Radiotherapy for soft tissue sarcomas (STS) of the hand is thought to be associated with poor function. The aim of this study was to compare the long-term functional outcome in patients with and without radiotherapy.

PATIENTS AND METHODS

At long-term follow-up (mean 10±5 years), 33 (13 males, 20 female) patients, were alive for review. The mean patient age at surgery was 33±17 years and 13 (39%) patients received radiotherapy (mean dose 55±6 Gy).

RESULTS

Postoperatively, the mean QuickDASH and MSTS93 were 7±8 and 92±8%, respectively. Comparing patients with and without radiotherapy, there was no difference (p>0.05) between the mean QuickDASH (5±5 vs. 8±9) or MSTS93 (93±9% vs. 91±8%). Surgical complication occurred more commonly in patients with radiotherapy (46% vs. 15%, p=0.10).

CONCLUSION

The use of radiotherapy was associated with a higher rate of complications, however, was not associated with a worse long-term functional outcome in patients with hand STS.

Long-term primary results of accelerated partial breast irradiation after breast-conserving surgery for early-stage breast cancer: a randomised, phase 3, equivalence trial

BACKGROUND

Whole-breast irradiation after breast-conserving surgery for patients with early-stage breast cancer decreases ipsilateral breast-tumour recurrence (IBTR), yielding comparable results to mastectomy. It is unknown whether accelerated partial breast irradiation (APBI) to only the tumour-bearing quadrant, which shortens treatment duration, is equally effective. In our trial, we investigated whether APBI provides equivalent local tumour control after lumpectomy compared with whole-breast irradiation.

METHODS

We did this randomised, phase 3, equivalence trial (NSABP B-39/RTOG 0413) in 154 clinical centres in the USA, Canada, Ireland, and Israel. Adult women (>18 years) with early-stage (0, I, or II; no evidence of distant metastases, but up to three axillary nodes could be positive) breast cancer (tumour size ≤3 cm; including all histologies and multifocal breast cancers), who had had lumpectomy with negative (ie, no detectable cancer cells) surgical margins, were randomly assigned (1:1) using a biased-coin-based minimisation algorithm to receive either whole-breast irradiation (whole-breast irradiation group) or APBI (APBI group). Whole-breast irradiation was delivered in 25 daily fractions of 50 Gy over 5 weeks, with or without a supplemental boost to the tumour bed, and APBI was delivered as 34 Gy of brachytherapy or 38·5 Gy of external bream radiation therapy in 10 fractions, over 5 treatment days within an 8-day period. Randomisation was stratified by disease stage, menopausal status, hormone-receptor status, and intention to receive chemotherapy. Patients, investigators, and statisticians could not be masked to treatment allocation. The primary outcome of invasive and non-invasive IBTR as a first recurrence was analysed in the intention-to-treat population, excluding those patients who were lost to follow-up, with an equivalency test on the basis of a 50% margin increase in the hazard ratio (90% CI for the observed HR between 0·667 and 1·5 for equivalence) and a Cox proportional hazard model. Survival was assessed by intention to treat, and sensitivity analyses were done in the per-protocol population. This trial is registered with ClinicalTrials.gov, NCT00103181.

FINDINGS

Between March 21, 2005, and April 16, 2013, 4216 women were enrolled. 2109 were assigned to the whole-breast irradiation group and 2107 were assigned to the APBI group. 70 patients from the whole-breast irradiation group and 14 from the APBI group withdrew consent or were lost to follow-up at this stage, so 2039 and 2093 patients respectively were available for survival analysis. Further, three and four patients respectively were lost to clinical follow-up (ie, survival status was assessed by phone but no physical examination was done), leaving 2036 patients in the whole-breast irradiation group and 2089 in the APBI group evaluable for the primary outcome. At a median follow-up of 10·2 years (IQR 7·5-11·5), 90 (4%) of 2089 women eligible for the primary outcome in the APBI group and 71 (3%) of 2036 women in the whole-breast irradiation group had an IBTR (HR 1·22, 90% CI 0·94-1·58). The 10-year cumulative incidence of IBTR was 4·6% (95% CI 3·7-5·7) in the APBI group versus 3·9% (3·1-5·0) in the whole-breast irradiation group. 44 (2%) of 2039 patients in the whole-breast irradiation group and 49 (2%) of 2093 patients in the APBI group died from recurring breast cancer. There were no treatment-related deaths. Second cancers and treatment-related toxicities were similar between the two groups. 2020 patients in the whole-breast irradiation group and 2089 in APBI group had available data on adverse events. The highest toxicity grade reported was: grade 1 in 845 (40%), grade 2 in 921 (44%), and grade 3 in 201 (10%) patients in the APBI group, compared with grade 1 in 626 (31%), grade 2 in 1193 (59%), and grade 3 in 143 (7%) in the whole-breast irradiation group.

INTERPRETATION

APBI did not meet the criteria for equivalence to whole-breast irradiation in controlling IBTR for breast-conserving therapy. Our trial had broad eligibility criteria, leading to a large, heterogeneous pool of patients and sufficient power to detect treatment equivalence, but was not designed to test equivalence in patient subgroups or outcomes from different APBI techniques. For patients with early-stage breast cancer, our findings support whole-breast irradiation following lumpectomy; however, with an absolute difference of less than 1% in the 10-year cumulative incidence of IBTR, APBI might be an acceptable alternative for some women.

FUNDING

National Cancer Institute, US Department of Health and Human Services.

Soft Tissue Sarcoma, Version 2.2018, NCCN Clinical Practice Guidelines in Oncology

Soft tissue sarcomas (STS) are rare solid tumors of mesenchymal cell origin that display a heterogenous mix of clinical and pathologic characteristics. STS can develop from fat, muscle, nerves, blood vessels, and other connective tissues. The evaluation and treatment of patients with STS requires a multidisciplinary team with demonstrated expertise in the management of these tumors. The complete NCCN Guidelines for STS provide recommendations for the diagnosis, evaluation, and treatment of extremity/superficial trunk/head and neck STS, as well as intra-abdominal/retroperitoneal STS, gastrointestinal stromal tumors, desmoid tumors, and rhabdomyosarcoma. This portion of the NCCN Guidelines discusses general principles for the diagnosis, staging, and treatment of STS of the extremities, superficial trunk, or head and neck; outlines treatment recommendations by disease stage; and reviews the evidence to support the guidelines recommendations.

Automated applicator digitization for high-dose-rate cervix brachytherapy using image thresholding and density-based clustering

PURPOSE

The purpose of the study was to develop and evaluate an automated digitization algorithm for high-dose-rate cervix brachytherapy, with the goal of reducing the duration of treatment planning, staff resources, variability, and potential for human error.

METHODS

An automated digitization algorithm was developed and retrospectively evaluated using treatment planning data from 10 patients with cervix cancer who were treated with a titanium tandem and ovoids applicator set. Applicators were segmented, without human interaction, by thresholding CT images to isolate high-density voxels and assigning the voxels to applicator and nonapplicator structures using HDBSCAN, a density-based linkage clustering algorithm. The applicator contours were determined from the centroid of the clustered voxels on each image slice and written to a treatment plan file. Automated contours were evaluated against manual digitization using distance and dosimetric metrics.

RESULTS

A close agreement between automatic and manual digitization was observed. The mean magnitude of contour disagreement for 10 patients equaled 0.3 mm. Hausdorff distances were ≤1.0 mm. The applicator tip coordinates had submillimeter agreement. The median and mean dose volume histogram parameter differences were less than or equal to 1% for high-risk clinical target volume D₉₀, high-risk clinical target volume D₉₅, bladder D_2cc, rectum D_2cc, large bowel D_2cc, and small bowel D_2cc. The average execution time for the automated algorithm was less than 30 s.

CONCLUSION

The digitization of titanium tandem and ovoids applicators for high-dose-rate brachytherapy treatment planning can be automated using straightforward thresholding and clustering algorithms. The adoption of automated digitization is expected to improve the consistency of treatment plans and reduce the duration of treatment planning.

Abstract GS4-04: Primary results of NSABP B-39/RTOG 0413 (NRG Oncology): A randomized phase III study of conventional whole breast irradiation (WBI) versus partial breast irradiation (PBI) for women with stage 0, I, or II breast cancer

Background: Conventional WBI after lumpectomy for early-stage breast cancer decreases ipsilateral breast tumor recurrence (IBTR), yielding comparable results to mastectomy. Accelerated PBI appears effective in reducing IBTR by treating only the tumor bed area. As the majority of IBTR occur at or in the vicinity of the tumor bed, we hypothesized that PBI would be as effective as WBI in controlling IBTR. The primary aim of NSABP B-39/RTOG 0413 was to determine if PBI provides equivalent local tumor control post lumpectomy compared to WBI in pts with early-stage breast cancer. The equivalency test was based on a 50% margin of increase in the hazard ratio (HR=1.5). Secondary endpoints included: overall survival (OS), recurrence-free interval (RFI), distant disease-free interval (DDFI), and toxicity.

Methods: Eligible pts had lumpectomy with histologically-free margins and 0-3 positive axillary nodes. Pts were stratified by stage, menopausal status, hormone receptor status, and intent to receive chemotherapy and then randomized to PBI or WBI. PBI was 10 fractions of 3.4-3.85 Gy, given twice daily with either brachytherapy or 3D external beam radiation. WBI was 50 Gy in 2 Gy fractions given daily with a sequential boost to the surgical cavity. Follow-up was every 6 mos for 5 yrs and then annually. All analyses were by intent-to-treat.

Results: From 3-21-05 to 4-16-13, 4216 pts were randomized: 2107 PBI; 2109 WBI. 61% were postmenopausal; 81% were hormone receptor-positive; 29% intended to receive chemotherapy. Stage distribution was: DCIS, 24%; invasive pN0, 65%; invasive pN1, 10%. As of 7-31-18, median follow-up was 10.2 yrs. There were 161 IBTRs as first events: 90 PBI v 71 WBI (HR 1.22; 90%CI 0.94-1.58). Per protocol-defined margin, to declare PBI and WBI equivalent regarding IBTR risk, the 90% CI for the observed HR had to lie entirely between 0.667 and 1.5. The percent of pts IBTR-free at 10 yrs was 95.2% PBI v 95.9% WBI. A statistically significant difference in the 10-yr RFI rate favored WBI (91.9% PBI v 93.4% WBI; HR 1.32; 95%CI 1.04-1.68; p=0.02). No statistically significant differences existed between PBI and WBI in DDFI (HR 1.31; 95%CI 0.91-1.91; p=0.15), OS (HR 1.10; 95%CI 0.90-1.35; p=0.35), or DFS (HR 1.12; 95%CI 0.98-1.29; p=0.11). Grade 3 toxicity was 9.6% PBI v 7.1% WBI, and grade 4-5 toxicity was 0.5% v 0.3%, respectively.

Discussion: PBI did not meet the criteria for equivalence to WBI in controlling IBTR based on the upper limit of the hazard ratio confidence interval. However, the absolute difference in 10-yr rate of IBTR was &lt;1% (4.8% PBI v 4.1% WBI). The risk of an RFI event was statistically significantly higher for PBI compared to WBI, but the absolute difference in 10-yr RFI rate was also small (8.1% PBI v 6.6% WBI). DDFI, OS, and DFS were not statistically different for PBI v WBI. Grade 3-5 toxicities, although low, were more common for PBI than WBI. The trial population was heterogeneous, ranging from Stage 0-2 breast cancer, and outcome by risk categories are being analyzed.

Support: U10CA180868, -180822, UG1CA189867.

Citation Format: Vicini FA, Cecchini RS, White JR, Julian TB, Arthur DW, Rabinovitch RA, Kuske RR, Parda DS, Ganz PA, Scheier MF, Winter KA, Paik S, Kuerer HM, Vallow LA, Pierce LJ, Mamounas EP, Costantino JP, Bear HD, Germaine I, Gustafson G, Grossheim L, Petersen IA, Hudes RS, Curran, Jr. WJ, Wolmark N. Primary results of NSABP B-39/RTOG 0413 (NRG Oncology): A randomized phase III study of conventional whole breast irradiation (WBI) versus partial breast irradiation (PBI) for women with stage 0, I, or II breast cancer [abstract]. In: Proceedings of the 2018 San Antonio Breast Cancer Symposium; 2018 Dec 4-8; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2019;79(4 Suppl):Abstract nr GS4-04.

Low dose radiotherapy is associated with local complications but not disease control in sacral chordoma

BACKGROUND

We reviewed the disease control and complications of the treatment of sacrococcygeal chordoma from four tertiary cancer centers with emphasis on the effects of radiotherapy in surgically treated patients.

METHODS

A total of 193 patients with primary sacrococcygeal chordoma from 1990 to 2015 were reviewed. There were 124 males, with a mean age of 59 ± 15 years and a mean follow-up of 7 ± 4 years. Eighty-nine patients received radiotherapy with a mean total dose of 61.8 ± 10.9 Gy.

RESULTS

The 10-year disease-free and disease-specific survival was 58% and 72%, respectively. Radiation was not associated with local recurrence (hazard ratio [HR], 1.13; 95% confidence interval [CI], 0.59-2.17; P = 0.71), metastases (HR, 0.93; 95% CI, 0.45-1.91; P = 0.85) or disease-specific survival (HR, 0.96; 95% CI, 0.46-2.00; P = 0.91). Higher doses (≥70 Gy; HR, 0.52; 95% CI, 0.20-1.32; P = 0.17) may be associated with reduced local recurrence. Radiotherapy was associated with wound complications (HR, 2.76; 95% CI, 1.64-4.82;, P < 0.001) and sacral stress fractures (HR, 4.73; 95% CI, 1.88-14.38; P < 0.001).

CONCLUSIONS

In this multicenter review, radiotherapy was not associated with tumor outcome but associated with complications. The routine use of radiotherapy with en-bloc resection of sacrococcygeal chordomas should be reconsidered in favor of a selective, individualized approach with a radiation dose of ≥70 Gy.

Soft Tissue Sarcoma, Version 2.2016, NCCN Clinical Practice Guidelines in Oncology

Soft tissue sarcomas (STS) are rare solid tumors of mesenchymal cell origin that display a heterogenous mix of clinical and pathologic characteristics. STS can develop from fat, muscle, nerves, blood vessels, and other connective tissues. The evaluation and treatment of patients with STS requires a multidisciplinary team with demonstrated expertise in the management of these tumors. The complete NCCN Guidelines for Soft Tissue Sarcoma (available at NCCN.org) provide recommendations for the diagnosis, evaluation, and treatment of extremity/superficial trunk/head and neck STS, as well as intra-abdominal/retroperitoneal STS, gastrointestinal stromal tumor, desmoid tumors, and rhabdomyosarcoma. This manuscript discusses guiding principles for the diagnosis and staging of STS and evidence for treatment modalities that include surgery, radiation, chemoradiation, chemotherapy, and targeted therapy.

Pelvis Ewing sarcoma: Local control and survival in the modern era

PURPOSE

Local control for Ewing sarcoma (ES) has improved in modern studies. However, it is unclear if these gains have also been achieved for pelvis tumors. The purpose of this study is to evaluate local control and survival in pelvis ES patients treated in the modern era.

METHODS

All pelvis ES patients diagnosed from 1990 to 2012 and seen at Mayo Clinic were identified. Factors relevant to survival and local control were analyzed.

RESULTS

The cohort consisted of 48 patients. Fifty-two percent had metastatic disease at diagnosis. The 5-year overall survival and event-free survival was 73% and 65%, respectively, for localized disease. The 5-year cumulative incidence of local recurrence was 19%, with a 26% incidence for radiation, 13% for surgery, and 0% for surgery + radiation (P = 0.54). All local failures occurred in-field. Sacral involvement by tumor trended toward a higher incidence of local recurrence (hazard ratio 3.06, P = 0.09). Patients treated with definitive radiation doses ≥5,600 cGy had a lower incidence of local recurrence (17% vs. 28%, P = 0.61).

CONCLUSIONS

Our study demonstrates excellent survival for localized tumors in the modern era. Anatomical localization within the pelvis likely correlates with outcomes. Local control remains problematic, especially for patients treated with definitive radiation. Though statistically not significant, surgery + radiation and definitive radiation dose ≥5,600 cGy were associated with the lowest incidence of local failure, suggesting treatment intensification may improve local control for pelvis ES.

Risk of Heart Failure With Preserved Ejection Fraction in Older Women After Contemporary Radiotherapy for Breast Cancer

BACKGROUND

Cardiomyocytes are resistant to radiation. However, cardiac radiation exposure causes coronary microvascular endothelial inflammation, a perturbation implicated in the pathogenesis of heart failure (HF) and particularly HF with preserved ejection fraction (HFpEF). Radiotherapy for breast cancer results in variable cardiac radiation exposure and may increase the risk of HF.

METHODS

We conducted a population-based case-control study of incident HF in 170 female residents of Olmsted County, Minnesota (59 cases and 111 controls), who underwent contemporary (1998-2013) radiotherapy for breast cancer with computed tomography-assisted radiotherapy planning. Controls were matched to cases for age, tumor side, chemotherapy use, diabetes mellitus, and hypertension. Mean cardiac radiation dose (MCRD) in each patient was calculated from the patient's computed tomography images and radiotherapy plan.

RESULTS

Mean age at radiotherapy was 69±9 years. Of HF cases, 38 (64%) had EF≥50% (HFpEF), 18 (31%) had EF<50% (HF with reduced EF), and 3 (5%) did not have EF measured. The EF was ≥40% in 50 of the 56 HF cases (89%) with an EF measurement. The mean interval from radiotherapy to HF was 5.8±3.4 years. The odds of HF was higher in patients with a history of ischemic heart disease or atrial fibrillation. The MCRD was 2.5 Gy (range, 0.2-13.1 Gy) and higher in cases (3.3±2.7 Gy) than controls (2.1±2.0 Gy; P=0.004). The odds ratio (95% confidence interval) for HF per log MCRD was 9.1 (3.4-24.4) for any HF, 16.9 (3.9-73.7) for HFpEF, and 3.17 (0.8-13.0) for HF with reduced EF. The increased odds of any HF or HFpEF with increasing MCRD remained significant after adjustment for HF risk factors and in sensitivity analyses matching by cancer stage rather than tumor side. Only 18.6% of patients experienced new or recurrent ischemic events between radiotherapy and the onset of HF.

CONCLUSIONS

The relative risk of HFpEF increases with increasing cardiac radiation exposure during contemporary conformal breast cancer radiotherapy. These data emphasize the importance of radiotherapy techniques that limit MCRD during breast cancer treatment. Moreover, these data provide further support for the importance of coronary microvascular compromise in the pathophysiology of HFpEF.

Establishment of practice standards in nomenclature and prescription to enable construction of software and databases for knowledge-based practice review

INTRODUCTION

Establishment of standards within a practice and across disease site groups for nomenclatures, prescription formatting, and measured dose-volume histogram (DVH) metrics is a key enabling step for creating software and database solutions to make routine aggregation of dosimetric data for all patients treated in a practice, practical. A process of physician-driven, iterative dialogs coupled with development of technical tools is required to implement the cultural and procedural changes. The cumulative reward for this effort is a database that can be used for defining practice norms, benchmarking against national standards, and tracking dosimetric effects of longitudinal practice pattern changes.

METHODS AND MATERIALS

A 4-year project was carried out to develop and introduce standardizations, modify processes, and develop computer-based tools for reporting, aggregation, and analysis of prescription and DVH metrics. Physician disease site groups developed 42 target and 81 normal tissue templates. From the database of 32,002 DVH metrics, benchmarking was illustrated for a subgroup of breast (281) and prostate (324) patients treated with conventional fractionation over a 16-month period. Breast patients were segregated according to prescription template used: simple (S, tangents only) vs complex (C, tangents + supraclavicular ± intramammary nodes) and left (S-L or C-L) versus right (S-R or C-R).

RESULTS

Prostate patients' median and 50% confidence intervals (CIs) for bladder, stated according to the nomenclature: the percentage of bladder volume receiving doses of ≥40 Gy (V40[%]), V65Gy[%], V70Gy[%], V75Gy[%], and V80Gy[%] were 45.5 (24.9-57.0), 15.6 (9.0-23.8), 7.6 (3.3-13.6), 2.0 (0.0-7.9), and 0.0 (0.0-1.4), respectively. Values for rectum: V50Gy[%], V60 Gy[%], V65Gy[%], V70Gy[%], and V75Gy[%] were 37.1 (27.8-43.5), 21.8 (15.6-25.5), 14.6 (9.6-18.0), 7.7 (1.9-12.3), and 1.0 (0-7.0), respectively. For breast patients, heart:mean Gray values were 1.5 (1.0-2.0), 3.1 (2.2-4.8), 0.4 (0.3-0.7), and 1.1 (0.8-2.2) for S-L, C-L, S-R, and C-R, respectively. Longitudinal, moving window plots of median, 50% CI, and 90% CI for 6-month periods demonstrated the effect of practice changes to reduce heart doses.

CONCLUSIONS

Standardization was challenging as a practice change, but has resulted in significant improvements for both our clinical and research efforts.

Retroperitoneal sarcoma (RPS) high risk gross tumor volume boost (HR GTV boost) contour delineation agreement among NRG sarcoma radiation and surgical oncologists

PURPOSE

Curative intent management of retroperitoneal sarcoma (RPS) requires gross total resection. Preoperative radiotherapy (RT) often is used as an adjuvant to surgery, but recurrence rates remain high. To enhance RT efficacy with acceptable tolerance, there is interest in delivering "boost doses" of RT to high-risk areas of gross tumor volume (HR GTV) judged to be at risk for positive resection margins. We sought to evaluate variability in HR GTV boost target volume delineation among collaborating sarcoma radiation and surgical oncologist teams.

METHODS

Radiation planning CT scans for three cases of RPS were distributed to seven paired radiation and surgical oncologist teams at six institutions. Teams contoured HR GTV boost volumes for each case. Analysis of contour agreement was performed using the simultaneous truth and performance level estimation (STAPLE) algorithm and kappa statistics.

RESULTS

HRGTV boost volume contour agreement between the seven teams was "substantial" or "moderate" for all cases. Agreement was best on the torso wall posteriorly (abutting posterior chest abdominal wall) and medially (abutting ipsilateral para-vertebral space and great vessels). Contours varied more significantly abutting visceral organs due to differing surgical opinions regarding planned partial organ resection.

CONCLUSIONS

Agreement of RPS HRGTV boost volumes between sarcoma radiation and surgical oncologist teams was substantial to moderate. Differences were most striking in regions abutting visceral organs, highlighting the importance of collaboration between the radiation and surgical oncologist for "individualized" target delineation on the basis of areas deemed at risk and planned resection.