Adjuvant Radiotherapy In Patients Research Articles

Abstract PO3-22-02: Concurrent chemotherapy with adjuvant radiation for patients with high-risk locally advanced breast cancer: safety and outcomes

Abstract Background: Patients with locally advanced breast cancer are at high risk for locoregional and distant recurrence and novel strategies are needed to enhance the efficacy of adjuvant radiation therapy. Selected chemotherapies act synergistically to safely radiosensitize residual disease to radiation therapy and may improve locoregional control when given concurrently. We report our institutional experience using concurrent chemotherapy with adjuvant radiotherapy for high-risk breast cancer patients. Methods: We conducted a retrospective study of breast cancer patients treated definitively with chemotherapy, surgery, and concurrent chemo-radiation (chemo-XRT) in the adjuvant setting between May 2006 and April 2019. The decision to combine chemotherapy with adjuvant conventionally fractionated radiation was based on provider discretion regarding patient’s risk of recurrence. The primary outcome was risk of locoregional recurrence (LRR). Secondary outcomes included disease free survival (DFS), overall survival (OS), and toxicity. The cumulative incidence of local recurrence was estimated with distant recurrence and death as competing risks. DFS and OS was estimated using the Kaplan-Meier method. Results: A total of 42 patients met inclusion criteria; of these 35 (83%) patients were receiving treatment for their initial breast cancer diagnosis and 7 (17%) patients were receiving treatment for a locoregional recurrence. Of the 35 patients treated in the primary setting, the majority had stage III disease (91%). Twenty-nine patients (83%) received neoadjuvant chemotherapy (NAC) all of which had residual disease after NAC and 6 patients (17%) received upfront primary surgery. Overall median total radiation dose was 57 Gy (range 45-68 Gy) with a majority receiving comprehensive regional nodal irradiation (25, 60%). Chemotherapy agents used for chemo-XRT included capecitabine (29, 69%), paclitaxel (8, 19%), and cisplatin (5, 12%). Median follow-up was 5 years after surgery (range: 4 months-16 years). At 5 years, the cumulative risk of LRR was 7% (95% CI: 2-21%). DFS was 47% (95% CI: 34-65%) and OS was 56% (95% CI: 42-74%). Of note, there were multiple exceptional responders, with OS of 51% at 10 years and 45% at 15 years. Chemo-XRT was well tolerated with 7% grade 3 toxicity (dermatitis), no grade 4 toxicity, and no new toxicity signals observed. Conclusions: Concurrent chemo-XRT for breast cancer patients with high risk locally advanced disease was safe and well tolerated. Chemo-XRT showed promise as a method to decrease risk of locoregional recurrence: the studied patient population was at very high risk, but only 7% of patients had a locoregional recurrence at 5 years. Further prospective evaluation of concurrent chemo-XRT is needed. Table 1. Patient characteristics and outcomes (N = 42) XX- XX Citation Format: Lynn Symonds, Sasha Swenson, Macklin Nguyen, Daniel Hippe, Hannah Linden, Jennifer M. Specht, WIlliam Gwin, Janice Kim. Concurrent chemotherapy with adjuvant radiation for patients with high-risk locally advanced breast cancer: safety and outcomes [abstract]. In: Proceedings of the 2023 San Antonio Breast Cancer Symposium; 2023 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2024;84(9 Suppl):Abstract nr PO3-22-02.

Platinum-based adjuvant chemoradiotherapy versus adjuvant radiotherapy in patients with head and neck adenoid cystic carcinoma

PurposeThe objective of the study was to assess the effectiveness and toxicity of platinum-based adjuvant chemoradiotherapy (POCRT) in comparison to postoperative radiotherapy (PORT) in patients with head and neck adenoid cystic carcinoma (HNACC).Materials and methodsThis retrospective study analyzed patients diagnosed with HNACC at our center between January 2010 and April 2020. A 1:1 propensity score matching method was used to create a matched cohort.ResultsIn this study, 206 patients were analyzed, with 147 patients (71.4%) receiving postoperative radiotherapy (PORT) and 59 patients (28.6%) receiving POCRT. Twenty-one patients experienced local–regional failure. The 3-, 5-, and 10-yr local–regional control (LRC) rate for the cohort were 92.0%, 90.6%, and 86.9%, respectively. In both the entire cohort and the matched cohort, the POCRT group exhibited superior LRC compared to the PORT group (Gray's test, all P < 0.05*). Multivariate analysis identified adjuvant concurrent chemotherapy as an independent prognostic factor for LRC (Competing risks regression, HR = 0.144, 95% CI 0.026–0.802, P = 0.027*). In addition, the POCRT group had higher incidences of upper gastrointestinal toxicity and hematologic toxicities, including leukopenia, neutropenia, and anemia (all P < 0.05*).ConclusionIn terms of reducing locoregional failures in HNACC patients, POCRT may potentially offer a more effective therapeutic approach than using PORT alone, although it also entails an augmented burden of treatment-related toxicity.

Tolerance of Concurrent Adjuvant Radiation Therapy and Pembrolizumab for Triple Negative Breast Cancer: Real Life Experience

The current standard-of-care management of locally advanced triple negative breast cancer (TNBC) is based on neoadjuvant chemo-immunotherapy with pembrolizumab, surgery, radiation therapy (RT), and adjuvant pembrolizumab. However, the safety of combining pembrolizumab with adjuvant breast RT has never been evaluated. This study evaluated the tolerance profile of concurrent pembrolizumab with adjuvant RT in patients with locally advanced TNBC. This bicentric ambispective study included all the patients with early and locally advanced TNBC who received neoadjuvant chemo-immunotherapy with pembrolizumab and adjuvant RT as part of their treatment. The tolerance profile of adjuvant RT was evaluated and compared in patients who received concurrent pembrolizumab and in patients for whom pembrolizumab was withheld. Fifty-five patients were included between July 2021 and March 2023. Twenty-eight patients received adjuvant RT with concurrent pembrolizumab (RT+P group), and 27 patients had pembrolizumab withheld while receiving adjuvant RT (RT-only group). Two patients developed grade ≥3 toxicity (1 grade 3 pain in the RT+P group and 1 grade 3 radiodermatitis in the RT-only group), and there were no differences in terms of toxicity between the RT-only and the RT+P groups. No cardiac or pulmonary adverse event was reported during RT. With a median follow-up of 12 months (10-26), no patient relapsed. In this study of limited size, the authors did not find a difference between the RT-only and RT+P groups in terms of toxicity. More studies and longer follow-up may add to the strength of this evidence.

Role of Adjuvant Radiotherapy in Patients with Cervical Cancer Undergoing Radical Hysterectomy.

The benefit of adjuvant radiotherapy (RT) after radical hysterectomy in patients with cervical cancer remains controversial. The aim of this study was to determine adjuvant RT's impact on survival in accordance with Sedlis criteria. Patients with early-stage cervical cancer undergoing radical hysterectomy between 2005 and 2022 at a single tertiary care institution were included. A multivariate analysis was performed to determinate if RT was an independent prognostic factor for recurrence or death. We also analysed whether there was a statistically significant difference in overall survival (OS) between patients who met only one or two Sedlis criteria, depending on whether they received adjuvant RT or not. 121 patients were included in this retrospective study, of whom 48 (39.7%) received adjuvant RT due to the presence of unfavourable pathological findings. In multivariate analysis, RT was not found to be a statistically significant prognostic factor for OS (p = 0.584) or disease-free survival (DFS) (p = 0.559). When comparing patients who met one or two Sedlis criteria, there were no statistically significant differences in OS between RT and no adjuvant treatment in either group. Since the selection of patients with cervical cancer eligible for surgery is becoming more accurate, adjuvant RT might not be necessary for patients with intermediate risk factors.

OR08-06 Adjuvant Radiation Therapy Is Not Associated With A Survival Benefit After R0 Resection In Non-Metastatic Adrenocortical Carcinoma

Abstract Disclosure: Y.J. Lee-Saxton: None. C.E. Egan: None. T.E. Marshall: None. A. Tumati: None. T. Beninato: None. R. Zarnegar: None. T.J. Fahey: None. B.M. Finnerty: None. Introduction: The benefit of adjuvant radiation therapy (RT) in adrenocortical carcinoma (ACC) is not well characterized, particularly for those who undergo initial R0 surgical resection without evidence of metastatic disease. We aimed to identify factors associated with administration of adjuvant RT in these patients, and to determine the association between adjuvant RT and overall survival in patients with non-metastatic ACC who underwent R0 surgical resection. Methods: The National Cancer Database was queried for histologic codes denoting ACC from 2004-2018. Patients who underwent R0 resection without evidence of metastatic disease were included and placed into two cohorts - those who underwent adjuvant RT and those who did not. Patients with incomplete or unknown data regarding clinically relevant variables were excluded from analysis. A multivariable logistic regression was performed to identify predictors of adjuvant RT administration. A multivariable Cox regression was performed to identify factors associated with overall survival (OS). Kaplan-Meier survival estimates and log-rank test were also performed to assess the impact of adjuvant RT on OS. Results: 388 patients were identified: 51 (13.1%) patients received adjuvant RT, while 337 (86.9%) did not. Adjuvant chemotherapy administration was the only factor associated with administration of adjuvant RT (OR 6.45, 95% CI 3.02 - 13.8, p&amp;lt;0.001). No significant difference was observed between the Kaplan-Meier survival estimates of the two cohorts (p=0.54). After adjusting for patient characteristics including age, sex, co-morbidity index, race, receipt of chemotherapy, and tumor characteristics including tumor size, tumor grade, pathologic tumor stage, and pathologic nodal stage, adjuvant RT was not associated with improved OS in patients who underwent R0 resection (HR 1.01, 95% CI 0.63 - 1.60, p=0.98). However, tumor size &amp;gt;6cm (HR 1.54, 95% CI 1.03 - 2.32, p=0.04), high tumor grade (HR 3.46, 95% CI 1.83 - 6.55, p&amp;lt;0.001), and pathologic N1 stage (HR 2.30, 95% CI 1.06 - 4.94, p=0.03) were associated with worse OS in patients who underwent R0 resection. Conclusions: Treatment with adjuvant RT in patients with ACC who underwent R0 resection was not associated with an OS benefit. Further studies assessing optimal treatment for large and high-grade tumors with lymph node metastases are warranted. Presentation: Friday, June 16, 2023

Adjuvant Radiotherapy in Atypical Meningioma: Are the Risks Worth the Benefit?

Adjuvant radiotherapy (RT) improves progression-free survival (PFS) in atypical meningiomas. Herein, we assess whether the treatment-related acute and long-term toxicity of upfront RT in atypical meningioma patients versus surveillance merits the PFS benefit. In our prior single institution retrospective study of 230 patients with resected intracranial atypical meningiomas between 2000-2015, adjuvant RT was associated with a significantly lower risk of progression/recurrence compared to surveillance (HR = 0.21 [95% CI 0.11-0.41]; p<0.01), with 36% of surveillance patients eventually requiring salvage RT. In the current study, the acute (≤6 months) and long term (>6 months) RT-related toxicities from the same patient cohort for those who received adjuvant RT (n = 51) were evaluated and compared to those who received salvage RT (n = 64) in the surveillance group. Additionally, overall treatment-related toxicity at time of last follow up was obtained for comparison between the adjuvant RT (n = 51) vs surveillance (n = 179) group. All toxicities were graded per CTCAE v5.0. Kaplan-Meier analysis was used to calculate the cumulative incidence of toxicities; Pearson's chi-squared and log-rank test were used for comparison. Adjuvant RT as compared to salvage RT was generally associated with greater RT-related toxicities both in the acute (90% vs 69%, p = 0.006) and long term (57% vs 33%, p = 0.010). While there was no significant difference in grade 3-4 acute toxicities, long term grade 3-4 toxicities (including headache, seizure, vision loss, neuromotor deficit, and neurocognitive deficit) were present in 14% of adjuvant vs 3% of salvage RT group (p = 0.035). Radionecrosis occurred in 18% of adjuvant RT vs 8% of salvage RT group (p = 0.11). Between adjuvant RT vs surveillance groups, any-treatment related toxicity at last follow up was greater with adjuvant RT (31% vs 15%; p = 0.006), with trend towards greater grade 3-4 toxicities (including headache, vision loss, neuromotor deficit, neurocognitive deficit, and cerebral edema) as well (8% vs 3%; p = 0.101). Cumulative incidence of treatment-related neuromotor deficit (any grade) was significantly greater in the adjuvant RT vs surveillance group with 14% vs 2% at 10 years (p = 0.004). There was no difference in rate of cerebrovascular accident between adjuvant RT (6%) vs surveillance (4%) groups (p = 0.83). Adjuvant RT for patients with atypical meningioma was associated with greater acute and long-term treatment toxicities. Potential RT-related toxicity and impact on quality-of-life should thus be carefully weighed against the tumor control benefit of RT in deciding the optimal use and timing of RT.

Short Course Adjuvant Vaginal Cuff Brachytherapy (VCB) in Early Endometrial Cancer: Primary Endpoint Results of the SAVE Randomized Clinical Trial

Prospective trials in early stage endometrial cancer demonstrate increased locoregional control with adjuvant radiotherapy for patients with high risk features. VCB is widely utilized, yet there is substantial practice variation and limited randomized data examining optimal dose/fractionation. We aimed to study the safety and efficacy of short course VCB compared to commonly used regimens. We conducted a prospective, randomized, multicenter trial examining short course adjuvant VCB (11 Gy x 2 fractions at the surface) compared with other standard regimens (7 Gy x 3 fractions at 0.5 cm depth, 6 Gy x 5 fractions at the surface, or 5-5.5 Gy x 4 fractions at 0.5 cm depth). Eligible patients underwent hysterectomy and had pathologically confirmed endometrioid adenocarcinoma, serous, clear cell, or carcinosarcoma. Patients with stage I and II cancers were included, with lymphovascular invasion (LVI) required for stage IAG1. The primary outcome was Global Health Status measured by the EORTC QLQ-C30 with a pre-specified non-inferiority margin of 15 points. Secondary outcomes included patient-reported outcomes, toxicities as assessed by CTCAEv5, and patterns of recurrence. Data were collected at each brachytherapy fraction and at 1-, 6-, and 12-month follow-up. One hundred eight patients were enrolled, 54 in each study arm. Data completion was 94%, 91%, and 77% at 1 month, 6 months, and 12 months, respectively. 70% of patients had endometrioid adenocarcinoma, 18% serous carcinoma, and 12% other histologies. 23% were FIGO grade 1, 33% grade 2, and 43% grade 3 or high risk histologies. The majority of patients were stage I (56% IA, 38% IB). 22% of patients had LVI. The QLQ-C30 Global Health Status for the experimental arm was within the predefined boundary and thus 2 fractions were non-inferior to standard of care at one month (p = 0.000005) and 12 months (p = 0.0005). Using EORTC EN24 for patient reported vaginal/sexual, urologic, and gastrointestinal symptoms, the change in mean patient reported symptom score from baseline to 1 month and baseline to 12 months were not significantly different between arms. Using CTCAEv5, 51 patients experienced short-term AEs related to study treatment, 20 in the experimental arm and 31 in the control arm (p = 0.053). All study treatment-related AEs were grade 1-2, except for two grade 3-4 AEs, both on the control arm. At median follow-up of 19 months, the isolated vaginal control rate in each arm was 100%. There was no significant difference in the total number of recurrences between study arms, with 3 distant and 3 distant/pelvic/vaginal recurrences in the experimental arm, and 2 distant, 2 pelvic, and 1 pelvic/vaginal recurrence in the control arm. Short course VCB is safe with acceptable acute toxicity and non-inferior patient reported outcomes. Short course VCB improves patient convenience and may improve access to care for rural or underserved populations while providing similar local control.

The effect of adjuvant radiotherapy after breast-conserving surgery in elderly women with T1-2N0 estrogen receptor-negative breast cancer.

To evaluate whether adjuvant radiotherapy (RT) following breast-conserving surgery (BCS) results in better survival among women ≥ 70 years with T1-2N0 estrogen receptor (ER)-negative breast cancer. In this retrospective cohort study, we included patients who met the inclusion criteria between 2010 and 2015 from the Surveillance, Epidemiology, and End Results (SEER) program. Univariate and Multivariate Cox proportional analysis were used to identify the risk factors for overall survival (OS) and breast cancer-specific survival (BCSS). Kaplan-Meier survival analysis was used to compare the prognosis of patients with or without adjuvant RT. Propensity score matching (PSM) was applied to perform a 1:1 matched case-control analysis. A total of 4201 women were included in this study, with a median follow-up time of 64 months (range: 0-107 months). Of these patients, 2811 (66.9%) received adjuvant RT, while 1390 (33.1%) did not. Patients who did not receive adjuvant RT were more likely to be aged ≥ 80 years old, have a single marital status, larger tumors, and HER2-positive status (p < 0.05). Multivariate Cox proportional analysis indicated that receiving adjuvant RT was an independent factor associated with better OS and BCSS before and after PSM (P < 0.001). The survival curves before and after PSM showed that patients achieved an improved OS and BCSS from adjuvant RT (P < 0.005). In the subgroup analysis, there was no survival benefit trend from adjuvant RT in patients who were ≥ 80 years, or those with T1mic+T1a, T1b tumors. The use of RT following BCS in older women with T1-2N0 ER-negative breast cancer is associated with improve OS and BCSS. However, the potential benefit may be relatively limited for patients ≥ 80 years, or those with T1mic+T1a, T1b tumors.

European consensus-based interdisciplinary guideline for invasive cutaneous squamous cell carcinoma: Part 2. Treatment–Update 2023

In order to update recommendations on treatment, supportive care, education, and follow-up of patients with invasive cutaneous squamous cell carcinoma (cSCC), a multidisciplinary panel of experts from the European Association of Dermato-Oncology (EADO), the European Dermatology Forum (EDF), the European Society for Radiotherapy and Oncology (ESTRO), the European Union of Medical Specialists (UEMS), the European Academy of Dermatology and Venereology (EADV), and the European Organisation of Research and Treatment of Cancer (EORTC) was formed. Recommendations were based on an evidence-based literature review, guidelines, and expert consensus. Treatment recommendations are presented for common primary cSCC (low risk, high risk), locally advanced cSCC, regional metastatic cSCC (operable or inoperable), and distant metastatic cSCC. For common primary cSCC, the first-line treatment is surgical excision with postoperative margin assessment or micrographically controlled surgery. Achieving clear surgical margins is the most important treatment consideration for patients with cSCCs amenable to surgery. Regarding adjuvant radiotherapy for patients with high-risk localised cSCC with clear surgical margins, current evidence has not shown significant benefit for those with at least one high-risk factor. Radiotherapy should be considered as the primary treatment for non-surgical candidates/tumours. For cSCC with cytologically or histologically confirmed regional nodal metastasis, lymph node dissection is recommended. For patients with metastatic or locally advanced cSCC who are not candidates for curative surgery or radiotherapy, anti-PD-1 agents are the first-line systemic treatment, with cemiplimab being the first approved systemic agent for advanced cSCC by the Food and Drugs Administration/European Medicines Agency. Second-line systemic treatments for advanced cSCC, include epidermal growth factor receptor inhibitors (cetuximab) combined with chemotherapy or radiotherapy. Multidisciplinary board decisions are mandatory for all patients with advanced cSCC, considering the risks of toxicity, the age and frailty of patients, and co-morbidities, including immunosuppression. Patients should be engaged in informed, shared decision-making on management and be provided with the best supportive care to improve symptom management and quality of life. The frequency of follow-up visits and investigations for subsequent new cSCC depends on underlying risk characteristics.

Association of Race, Ethnicity, Insurance, and Language and Rate of Breast-Conserving Therapy Among Women With Nonmetastatic Breast Cancer at an Urban, Safety-Net Hospital

IntroductionBreast-conserving therapy (BCT), specifically breast-conserving surgery (BCS) and adjuvant radiation, provides an equivalent alternative to mastectomy for eligible patients. However, previous studies have shown that BCT is underused in the United States, particularly among marginalized demographic groups. In this study, we examine the association between race, ethnicity, insurance, and language and rate of BCS among patients treated at an academic, safety-net hospital. Materials and MethodsWe conducted a retrospective cohort study of 520 women with nonmetastatic breast cancer diagnosed and treated at an academic, safety-net hospital (2009-2014). We assessed eligibility for BCT and then differences in the rate of BCT among eligible patients by race, ethnicity, insurance, and language. Reasons for not undergoing BCT were documented. ResultsMedian age was 60 y; 55.9% were non-White, 31.9% were non-English–speaking, 15.6% were Hispanic, and 47.4% were Medicaid/uninsured. Three hundred seventy one (86.3%) underwent BCS; within this group, 324 (87.3%) completed adjuvant radiation. Among patients undergoing mastectomy, 30 patients (36.7%) were eligible for BCT; within this group, reasons for mastectomy included patient preference (n = 28) and to avoid possible re-excision or adjuvant radiation in patients with significant comorbidities (n = 2). Eligibility for BCT varied by ethnicity (Hispanic [100%], Non-Hispanic [92%], P = 0.02), but not race, language, or insurance. Among eligible patients, rate of BCS varied by age (<50 y [84.9%], ≥50 y [92.9%], P = 0.01) and ethnicity (Hispanic [98.5%], Non-Hispanic [91.3%], P = 0.04), but not race, language, or insurance. ConclusionsAt our safety-net hospital, the rate of BCS among eligible patients did not vary by race, language, or insurance. Excluding two highly comorbid patients, all patients who underwent mastectomy despite being eligible for BCT were counseled regarding BCS and expressed a preference for mastectomy. Further research is needed to understand the value of BCT in the treatment of breast cancer, to ensure informed decision-making, address potential misconceptions regarding BCT, and advance equitable care for all patients.

Adjuvant radiotherapy mitigates impact of perineural invasion on oncologic outcomes in early-stage oral cavity squamous cell carcinoma. A multi-institutional analysis of 557 patients

ObjectivesUnderstand the prognostic impact of perineural invasion (PNI) in early-stage oral cavity squamous cell carcinoma (OCSCC). Assess the influence of adjuvant radiotherapy on outcomes of patients with PNI-positive early-stage OCSCC. Materials and MethodsRetrospective seven-institution cohort study including patients with pathologic T1-2 N0-1 OCSCC who underwent primary surgery with negative margins. Outcomes included disease-free survival (DFS) and locoregional control (LRC). Cox proportional hazards models were used to evaluate oncologic outcomes. Interaction terms were introduced to assess relationships between PNI and adjuvant radiotherapy. ResultsAmong 557 patients (mean (SD) age 61.0 (13.9), 47.2% female, 66.6% pathologic T1, 93.5% pathologic N0), 93 had PNI-positive tumors, among which 87.1% underwent neck dissection and 39.6% received radiotherapy. On multivariable analysis, PNI was associated with lower DFS and LRC. Adjuvant radiotherapy was not associated with improved outcomes on multivariable analysis of the entire cohort. However, among patients with PNI-positive tumors, adjuvant radiotherapy significantly decreased hazard for DFS. ConclusionAmong patients with low-risk, early-stage OCSCC, PNI was associated with worse DFS and LRC. In patients with PNI-positive tumors, adjuvant radiotherapy lowered hazard for DFS on multivariable analysis. These data support using adjuvant radiotherapy for patients with early-stage OCSCC with PNI.

Study Protocol of the Bladder Adjuvant RadioTherapy (BART) Trial: A Randomised Phase III Trial of Adjuvant Radiotherapy Following Cystectomy in Bladder Cancer

AimsTo assess the efficacy and safety of adjuvant radiotherapy in patients with high-risk muscle-invasive bladder cancer (MIBC) following radical cystectomy (RC) and chemotherapy. Materials and methodsThe BART (Bladder Adjuvant RadioTherapy) trial is an ongoing multicentric, randomised, phase III trial comparing the efficacy and safety of adjuvant radiotherapy versus observation in patients with high-risk MIBC. The key eligibility criteria include ≥pT3, node-positive (pN+), positive margins and/or nodal yield <10, or, neoadjuvant chemotherapy for cT3/T4/N+ disease. In total, 153 patients will be accrued and randomised, in a 1:1 ratio, to either observation (standard arm) or adjuvant radiotherapy (test arm) following surgery and chemotherapy. Stratification parameters include nodal status (N+ versus N0) and chemotherapy (neoadjuvant chemotherapy versus adjuvant chemotherapy versus no chemotherapy). For patients in the test arm, adjuvant radiotherapy to cystectomy bed and pelvic nodes is planned with intensity-modulated radiotherapy to a dose of 50.4 Gy in 28 fractions using daily image guidance. All patients will follow-up with 3-monthly clinical review and urine cytology for 2 years and subsequently 6 monthly until 5 years, with contrast-enhanced computed tomography abdomen pelvis 6 monthly for 2 years and annually until 5 years. Physician-scored toxicity using Common Terminology Criteria for Adverse Events version 5.0 and patient-reported quality of life using the Functional Assessment of Cancer Therapy – Colorectal questionnaire is recorded pre-treatment and at follow-up. Endpoints and statisticsThe primary endpoint is 2-year locoregional recurrence-free survival. The sample size calculation was based on the estimated improvement in 2-year locoregional recurrence-free survival from 70% in the standard arm to 85% in the test arm (hazard ratio 0.45) using 80% statistical power and a two-sided alpha error of 0.05. Secondary endpoints include disease-free survival, overall survival, acute and late toxicity, patterns of failure and quality of life. ConclusionThe BART trial aims to evaluate whether contemporary radiotherapy after standard-of-care surgery and chemotherapy reduces pelvic recurrences safely and also potentially affects survival in high-risk MIBC.

Adjuvant Radiotherapy in Patients with Squamous Cell Carcinoma of the Oral Cavity or Oropharynx and Solitary Ipsilateral Lymph Node Metastasis (pN1)-A Prospective Multicentric Cohort Study.

(1) Background: Evaluation of impact of adjuvant radiation therapy (RT) in patients with oral squamous cell carcinoma of the oral cavity/oropharynx (OSCC) of up to 4 cm (pT1/pT2) and solitary ipsilateral lymph node metastasis (pN1). A non-irradiated group with clinical follow-up was chosen for control, and survival and quality of life (QL) were compared; (2) Methods: This prospective multicentric comprehensive cohort study included patients with resected OSCC (pT1/pT2, pN1, and cM0) who were allocated into adjuvant radiation therapy (RT) or observation. The primary endpoint was overall survival. Secondary endpoints were progression-free survival and QL after surgery; (3) Results: Out of 27 centers, 209 patients were enrolled with a median follow-up of 3.4 years. An amount of 137 patients were in the observation arm, and 72 received adjuvant irradiation. Overall survival did not differ between groups (hazard ratio (HR) 0.98 [0.55-1.73], p = 0.94). There were fewer neck metastases (HR 0.34 [0.15-0.77]; p = 0.01), as well as fewer local recurrences (HR 0.41 [0.19-0.89]; p = 0.02) under adjuvant RT. For QL, irradiated patients showed higher values for the symptom scale pain after 0.5, two, and three years (all p < 0.05). After six months and three years, irradiated patients reported higher symptom burdens (impaired swallowing, speech, as well as teeth-related problems (all p < 0.05)). Patients in the RT group had significantly more problems with mouth opening after six months, one, and two years (p < 0.05); (4) Conclusions: Adjuvant RT in patients with early SCC of the oral cavity and oropharynx does not seem to influence overall survival, but it positively affects progression-free survival. However, irradiated patients report a significantly decreased QL up to three years after therapy compared to the observation group.

Efficacy and toxicity of adjuvant radiotherapy in recurrent melanoma after adjuvant immunotherapy

BackgroundIn patients with stage III melanoma, despite surgical resection and adjuvant systemic therapy, locoregional recurrences still occur. The randomized, phase III Trans-Tasman Radiation Oncology Group (TROG) 02.01 trial demonstrated that...

Abstract GS5-12: Hypofractionated Radiotherapy in patients with Breast Cancer (HRBC): Acute toxicity data of a phase III randomized study

Abstract Background HRBC is a phase III randomized open label study of adjuvant radiotherapy in patients with breast cancer. In this study we compared a 3 weeks radiation schedule with 2 weeks. Materials and methods Patients with breast cancer, stage I-III, post mastectomy or after breast conservative surgery who needed adjuvant locoregional radiotherapy were randomized to 34Gy in 10 fractions over 2 weeks (study arm) or 35Gy in 15 fractions over 3 weeks to the chest wall and 40Gy/15#/3wks to breast and supraclavicular fossa (control arm). Boost dose when indicated was 8Gy/2# in both the arms. Patients were planned on simulator with 2 tangential fields to breast/chest wall and incident supraclavicular fossa field. Acute toxicity was assessed using a RTOG grading system. Assessment was carried out weekly during radiotherapy and at 4 weeks after treatment by the physician. Cosmetic outcome was assessed using Harvard/NSABP/RTOG scale. The toxicity between the two arms was compared using Fisher’s exact test. The trial was approved by institutional ethics committee. This trial is registered with ClinicalTrials.gov, number NCT04075058. Results This study included 1121 patients. Median follow up was 35 months (range 6-84 months). Mean age was 48 year (range 24-80 years). The patient characteristics were comparable between the two arms except for more mastectomies in the 3 week arm and more node positive patients in the 2 week arm. There were more oestrogen receptor positive tumors in the 3 week arm. Acute skin toxicities were comparable between the two arms. Grade 2 and 3 skin toxicity was 98(17%) and 82(15%); and 16(3%) and 10(2%) in the 3 week and 2 week arm (p=0.15), respectively. Cosmetic outcome was significantly better in 2 week arm 94% as compared to 90% in the 3 week arm (p=0.016). Conclusion The two radiation schedules were comparable in terms of acute skin toxicity. Cosmetic outcome was better in the 2 week schedule. Citation Format: Budhi Singh Yadav, Divya Dahiya, Manish Gupta. Hypofractionated Radiotherapy in patients with Breast Cancer (HRBC): Acute toxicity data of a phase III randomized study [abstract]. In: Proceedings of the 2022 San Antonio Breast Cancer Symposium; 2022 Dec 6-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2023;83(5 Suppl):Abstract nr GS5-12.

Adjuvant Radiation and Survival Following Surgical Resection of Sinonasal Adenocarcinoma.

This study aims to investigate the utility of adjuvant radiation in patients who undergo surgical resection for the management of node-negative sinonasal adenocarcinoma (SNAC). Retrospective database review. The 2004-2016 National Cancer Data Base (NCDB) was used to extract patients with surgically resected node-negative SNAC. Kaplan-Meier survival analysis and Cox-Proportional Hazards Modelling were used to analyze the impact of adjuvant radiation on overall survival (OS) following surgery. 349 patients with SNAC underwent surgical resection. Of these patients, 154 (44.1%) received adjuvant radiotherapy (RT). Although there was no significant difference in race, age, or sex of those receiving RT, those receiving RT have more advanced diseases and are more likely to have positive margins. Kaplan Meier analysis showed no significant difference in 5-year OS in patient who received adjuvant RT in comparison to those who underwent surgical resection alone (65.7% vs. 72.6%, respectively; p=0.378). In addition, when looking at only patients with positive margins, 5-year OS still did not have a significant difference (73.8% vs. 61.6%, respectively; p=0.101). Only patients with clinical AJCC T4 showed a statistically significant survival benefit with adjuvant RT (56.9% vs. 29.9%, respectively; p=0.009). Adjuvant RT does not appear to provide a significant survival benefit in patients with resected SNAC, with the exception of those with clinically AJCC T4 disease. 4 Laryngoscope, 133:2603-2612, 2023.

Prospective analysis of the impact of adjuvant treatment with external beam radiation therapy and vaginal brachytherapy on health-related quality of life in patients with early-stage endometrioid endometrial carcinoma.

Our study evaluates the impact of adjuvant treatment with external beam radiotherapy (EBRT) combined with vaginal high dose rate brachytherapy (HDR BT) on health related quality of life (HRQL) in patients with early stage endometrioid endometrial carcinoma. From March 2019 to February 2021, 60 patients were enrolled with early stage endometrioid endometrial carcinoma, and qualified to adjuvant treatment after hysterectomy. HRQL was assessed using the EORTC QLQ-C30 questionnaire, with the endometrial cancer-specific HRQL module EORTC QLQ-EN24. Questionnaires were completed in four timepoints during adjuvant radiotherapy. A significant decrease in mean global health status / quality of life (p < 0.001) and role functioning (p = 0.028) was noted, as assessed in EORTC QLQ-C30 scale. Among the EORTC QLQ-C30 symptoms scales, significant differences were noted in the fatigue scale (p = 0.003), pain scale (p = 0.001), constipation scale (p < 0.001) and diarrhea scale (p < 0.001) over time. The EORTC QRQ-EN24 analysis showed significant deterioration in the urological symptoms scale (p < 0.001), gastrointestinal symptoms scale (p < 0.001) and in the mean pain in back and pelvis scale (p = 0.003). Adjuvant radiotherapy in patients with early-stage endometrioid endometrial cancer after hysterectomy is associated with worse quality of life, especially due to the toxicity of the treatment in relation to the gastrointestinal tract and urinary system.

Head and neck cancer: hypofractionated adjuvant radiation therapy

INTRODUCTION: Effect of adiuvant radiation therapy (RT) on oncologic outcomes is well-known and confirmed by different trials. Optimal time to start RT is 6–8 weeks after surgery. Increasing duration of RT delay beyond that interval leads to decrease in overall survival (OS) and makes loco-regional recurrence (LRC) more probable. However, more than 50% patients do not receive adjuvant treatment in time (Mitra S. et al., 2022). Overall treatment time (77–100 days) is another factor that influences effectiveness of adjuvant RT. In order to keep within that time limits non-conventional regimens of RT can be used.OBJECTIVE: To test safety and feasibility of hypofractionated adjuvant RT in patients with locally advanced squamous cell carcinoma of oral cavity and oropharynx.MATERIALS AND METHODS: Patients with stage III–IV squamous cell carcinoma of oral cavity and oropharynx (n=11) who underwent surgery and have to recieve adjuvant RT in 8 weeks and more after surgery are included. Dose was delivered using Volumetric Modulated Arc Therapy (VMAT) and simultaneous integrated boost.RESULTS: Patients (n=11) completed RT successfully. Surgery-to-RT interval ranges between 9 and 15 weeks. Dose per fraction on high-risk-CTV varies between 2,5 and 2,75 Gy. Acute side-effects (oral mucositis grade II) presented after 27–32 Gy (11–13 fractions) in 9 patient out of 11 and reached maximum (oral mucositis grade III, radiation dermatitis grade II) at the end of the treatment.CONCLUSIONS: Hypofractionated adjuvant RT (VMAT) can be safely used in patients with locally advanced squamous cell carcinoma of oral cavity and oropharynx and local acute toxicity can be controlled.

Outcomes of adjuvant radiation therapy after chemotherapy in resected extrahepatic cholangiocarcinoma: A National Cancer Database analysis.

Adjuvant capecitabine is considered a standard of care for resected cholangiocarcinoma per the BILCAP trial. The role of adjuvant radiation therapy in that trial was not addressed. This study was designed to examine the outcomes of adjuvant radiation in patients who received chemotherapy for resected cholangiocarcinoma. Using the National Cancer Database, the authors identified high-risk patients with resected extrahepatic cholangiocarcinoma with either positive nodes (N+) or margins (R1) who received adjuvant chemotherapy between 2006 and 2014. Overall survival (OS) was determined with the Kaplan-Meier method. Propensity score matching (PSM) and multivariate analysis (MVA) were performed to identify prognostic factors for survival. The authors identified 1478 patients after PSM who were included in the analysis. There was no difference in OS between patients receiving single-agent chemotherapy and patients receiving multiagent chemotherapy (p=.69). There was a significant OS benefit associated with radiation therapy. The median OS and the 5-year OS rate for radiated patients versus nonradiated patients were 34months and 33% versus 27months and 24% (p<.001) for the whole group, 30months and 29% versus 24months and 19% (p=.007) for the N+ subgroup, and 25months and 23% versus 20months and 12% (p=.03) for the R1 subgroup. MVA demonstrated that age, N stage, T stage, R1, and grade were associated with increased mortality, whereas adjuvant radiation was associated with decreased mortality (p<.001). This is the first study showing that adjuvant radiation therapy after chemotherapy resulted in a significant OS benefit for patients with resected high-risk extrahepatic cholangiocarcinoma. Trials are needed to address the role of radiation therapy in this population.

PO32 Presentation Time: 10:30 AM: Outcomes After Adjuvant Radiation in Patients with Early-Stage Endometrial Cancer with Mismatch Repair Defects

<h3>Purpose</h3> Although mismatch repair (MMR) deficiency is commonly identified in endometrial cancers, its significance on outcomes remains unknown. Our study aims to determine if MMR status affects clinical outcomes in early-stage endometrial cancer patients treated with adjuvant radiation therapy. <h3>Methods/Materials</h3> We identified 194 patients with FIGO 2009 stage I-II endometrioid endometrial cancer who underwent surgical resection followed by adjuvant radiation therapy at our institution with available MMR status. Locoregional recurrence (LRR) and distant metastases were analyzed using competing risk methods, and overall survival (OS) and progression free survival (PFS) were analyzed using Kaplan-Meier. <h3>Results</h3> The median age was 65 years, and the median follow-up time was 38 months. There were 73 patients (37.6%) with an MMR deficiency, and 121 (62.4%) patients with intact MMR. Eleven patients (5.7%) experienced LRR, and 14 patients (7.2%) experienced distant recurrence. The median OS and PFS of the cohort was not reached and MMR status was not associated with OS or PFS. MMR deficiency was significantly associated with the grade of the tumor (17.1% of grade 1 versus 54.4% of grade 2 and 46.9% of grade 3 patients (<i>p</i><0.01)), the depth of myometrial invasion (<i>p</i><0.01), and the presence of LVSI (<i>p</i><0.01). MMR status was not associated with the type of radiation delivered. In the entire cohort, patients who received external beam radiation therapy had significantly worse PFS than patients who underwent brachytherapy (<i>p</i>=0.03). In patients whose tumors were MMR deficient, there was also a significant difference in PFS based on the type of radiation delivered. Patients who underwent external beam radiation therapy (EBRT) had shorter PFS versus patients who underwent brachytherapy only (<i>p</i>=0.02). In patients with MMR deficient tumors, there was a significant correlation between radiation type and stage; patients with stage II disease were more likely to undergo both EBRT and brachytherapy (<i>p</i><0.01). After adjusting for stage, type of radiation delivered was trending towards significance (p=0.07). Greater depth of myometrial invasion was also associated with the use of both EBRT and brachytherapy (<i>p</i>=0.03). <h3>Conclusions</h3> Patients with stage I-II endometrial cancer have excellent oncologic outcomes with the use of adjuvant radiation therapy, regardless of MMR status.