Association Between Symptom Burden and Early Lymphatic Abnormalities After Regional Nodal Irradiation for Breast Cancer

PURPOSE

Dermal backflow visualized on near-infrared fluorescence lymphatic imaging (NIRF-LI) signals preclinical lymphedema that precedes the development of volumetrically defined lymphedema. We sought to evaluate whether dermal backflow correlates with patient-reported lymphedema outcomes (PRLO) surveys in breast cancer patients treated with regional nodal irradiation (RNI).

METHODS AND MATERIALS

Patients with breast cancer planned for axillary dissection and RNI prospectively underwent perometry, NIRF-LI, and PRLOs (the Lymphedema Symptom Intensity and Distress Survey [LSIDS] and QuickDASH) at baseline, after surgery, and at 6, 12, and 18 months after radiation. Clinical lymphedema was defined as an arm volume increase ≥5% over baseline. Trends over time were assessed using analysis of variance testing. The association between survey responses and both dermal backflow and lymphedema was assessed using a linear mixed-effects model.

RESULTS

Sixty participants completed at least 2 sets of measurements and surveys and were eligible for analysis. Fifty-four percent of patients had cT3-T4 disease, 53% cN3 disease, and 75% had a body mass index >25. Dermal backflow and clinical lymphedema increased from 10% to 85% and from 0% to 40%, respectively, from baseline to 18 months. In the adjusted model, soft tissue sensation, neurologic sensation, and functional LSIDS subscale scores were associated with presence of dermal backflow (all P < .05). Both dermal backflow and lymphedema were associated with QuickDASH score (P < .05).

CONCLUSIONS

In this high-risk cohort, we found highly prevalent early signs of lymphedema, with increased symptom burden from baseline. Presence of dermal backflow correlated with PRLO measures, highlighting a potential NIRF-LI use to identify patients for early intervention trials after RNI.

Radiation for inflammatory breast cancer: Updates

Inflammatory breast cancer (IBC) is a diagnosis based on a constellation of clinical features of edema (peau d'orange) of a third or more of the skin of the breast with a palpable border and a rapid onset of breast erythema. Incidence of IBC has increased over time, although it still makes up only 1-4% of all breast cancer diagnoses. Despite recent encouraging data on clinical outcomes, the published local-regional control rates remain consistently lower than the rates for non-IBC. In this review, we focus on radiotherapy, provide a framework for multi-disciplinary care for IBC, describe local-regional treatment techniques for IBC; highlight new directions in the management of patients with metastatic IBC and offer an introduction to future directions regarding the optimal treatment and management of IBC.

Phase II Trial of Definitive Therapy for Osseous Oligometastases in Breast Cancer

PURPOSE/OBJECTIVE(S)

Phase II data for consolidative local therapy for oligometastatic disease demonstrated improved outcomes for various malignancies. However, a randomized phase II study of oligometastatic breast cancer patients testing predominantly ablative dose radiotherapy (RT) did not demonstrate progression-free survival (PFS) benefit. We conducted a single-arm phase II trial evaluating local therapy as part of the multidisciplinary management of breast cancer patients with limited bone metastases.

MATERIALS/METHODS

Patients with synchronous (n = 15) and metachronous (n = 15) oligometastatic breast cancer involving ≤3 osseous sites were enrolled from July 2009 to April 2016 and treated to a total of 44 bone metastases. The trial closed early due to slow accrual. Following ≤9 months of systemic therapy, local therapy entailed surgery (n = 3) or RT delivered via conventional fractionation (≥60 Gy, n = 36) or stereotactic technique (27 Gy/3 fractions for spine mets, n = 6). When indicated, RT to the primary was delivered concurrently (n = 15). The primary endpoint was to determine PFS. Secondary endpoints were overall survival (OS), local control (LC) and toxicity. Outcomes were evaluated with Kaplan-Meier and univariate Cox proportional hazards analyses.

RESULTS

Of the 30 patients included in the trial, 23 (77%) had ER+ or PR+/HER2- disease, 4 (13%) had Her2+ disease, and 3 (10%) were triple negative. Median age was 53, and 20 patients (67%) presented with 1 distant metastasis. A total of 21 patients (70%) experienced disease progression at a median 20.5 months (IQR: 8.2-41.2), including 5 local failures among 44 treated bone metastases (11%). At a median follow-up of 76.7 mon (IQR: 45.4-108.8), the median PFS was 37.8 mon, with 2- and 5-year rates (95% CI) of 60% (45-80%) and 32% (19-55%), respectively. The 2- and 5-year OS rates were 93% (85-100%) and 64% (48-85%), respectively, and the 2- and 5-year LC rates were 91% (80-100%) and 71% (51-98%). For patients who achieved LC, median PFS was 47.7 months (IQR 12.2-73.0). Twenty-one patients (70%) received cytotoxic chemotherapy with or without endocrine therapy for newly diagnosed oligometastatic disease. Nine patients (30%) were still alive with no evidence of disease (NED) at a median 96.9 mon (range: 47.7-158.6). PFS was worse among triple negative patients (p = 0.03), with no difference based on synchronous vs non-synchronous presentation (p = 0.10), receipt of cytotoxic chemotherapy prior to definitive therapy (p = 0.08) or Her2+ status (p = 0.21). There were no Grade ≥3 adverse events.

CONCLUSION

Definitive, predominantly conventionally fractionated local therapy was associated with long-term NED status for 30% of patients with oligometastatic breast cancer involving osseous sites, with minimal treatment-associated toxicity. Developing randomized trials for breast cancer subsets may warrant consideration of standard fractionation regimen data and the need for strategies to identify patients who may benefit from definitive local therapy.

Prospective, early longitudinal assessment of lymphedema-related quality of life among patients with locally advanced breast cancer: The foundation for building a patient-centered screening program

BACKGROUND

We examined how breast cancer-related lymphedema (BCRL) affects health-related quality of life (HRQOL), productivity, and compliance with therapeutic interventions to guide structuring BCRL screening programs.

METHODS

We prospectively followed consecutive breast cancer patients who underwent axillary lymph node dissection (ALND) with arm volume screening and measures assessing patient-reported health-related quality of life (HRQOL) and perceptions of BCRL care. Comparisons by BCRL status were made with Mann-Whitney U, Chi-square, Fisher's exact, or t tests. Trends over time from ALND were assessed with linear mixed-effects models.

RESULTS

With a median follow-up of 8 months in 247 patients, 46% self-reported ever having BCRL, a proportion that increased over time. About 73% reported fear of BCRL, which was stable over time. Further in time from ALND, patients were more likely to report that BCRL screening reduced fear. Patient-reported BCRL was associated with higher soft tissue sensation intensity, biobehavioral, and resource concerns, absenteeism, and work/activity impairment. Objectively measured BCRL had fewer associations with outcomes. Most patients reported performing prevention exercises, but compliance decreased over time; patient-reported BCRL was not associated with exercise frequency. Fear of BCRL was positively associated with performing prevention exercises and using compressive garments.

CONCLUSIONS

Both incidence and fear of BCRL were high after ALND for breast cancer. Fear was associated with improved therapeutic compliance, but compliance decreased over time. Patient-reported BCRL was more strongly associated with worse HRQOL and productivity than was objective BCRL. Screening programs must support patients' psychological needs and aim to sustain long-term compliance with recommended interventions.

Optimizing Preventive Adjuvant Linac-Based (OPAL) Radiation: A Phase 2 Trial of Daily Partial Breast Irradiation

PURPOSE

Evidence supports use of partial-breast irradiation (PBI) in the management of early breast cancer, but the optimal dose-fractionation remains unsettled.

METHODS AND MATERIALS

We conducted a phase 2 clinical trial (OPAL trial) to evaluate a novel PBI dosing schedule of 35 Gy in 10 daily fractions. Patients with close (<2 mm) margins also received a boost of 9 Gy in 3 fractions. Eligible patients underwent margin-negative lumpectomy for ductal carcinoma in situ or estrogen receptor-positive invasive breast cancer, up to 3 cm, pTis-T2 N0. The primary outcome was any grade ≥2 toxic effect occurring from the start of radiation through 6 months of follow-up. Secondary outcomes included patient-reported cosmesis, breast pain, and functional status, measured using the Breast Cancer Treatment Outcomes Scale, and physician-reported cosmesis, measured using the Radiation Therapy and Oncology Group scale. The Cochran-Armitage trend test and multivariable mixed-effects longitudinal growth curve models compared outcomes for the OPAL study population with those for a control group of similar patients treated with whole-breast irradiation (WBI) plus boost.

RESULTS

All 149 patients enrolled on the OPAL trial received the prescribed dose, and 17.4% received boost. The median age was 64 years; 83.2% were White, and 73.8% were overweight or obese. With median follow-up of 2.0 years, 1 patient (0.7%) experienced in-breast recurrence. Prevalence of the primary toxicity outcome was 17.4% (26 of 149 patients) in the OPAL trial compared with 72.7% (128 of 176 patients) in the control WBI-plus-boost cohort (P < .001). In longitudinal multivariable analysis, treatment on the OPAL trial was associated with improved patient-reported cosmesis (P < .001), functional status (P = .004), breast pain (P = .004), and physician-reported cosmesis (P < .001).

CONCLUSIONS

Treatment with daily PBI was associated with substantial reduction in early toxicity and improved patient- and physician-reported outcomes compared with WBI plus boost. Daily external-beam partial-breast irradiation with 13 or fewer fractions merits further prospective evaluation.

Prediction of breast cancer-related lymphedema by dermal backflow detected with near-infrared fluorescence lymphatic imaging

PURPOSE

Mild breast cancer-related lymphedema (BCRL) is clinically diagnosed as a 5%-10% increase in arm volume, typically measured no earlier than 3-6 months after locoregional treatment. Early BCRL treatment is associated with better outcomes, yet amid increasing evidence that lymphedema exists in a latent form, treatment is typically delayed until arm swelling is obvious. In this study, we investigated whether near-infrared fluorescence lymphatic imaging (NIRF-LI) surveillance could characterize early onset of peripheral lymphatic dysfunction as a predictor of BCRL.

METHODS

In a prospective, longitudinal cohort/observational study (NCT02949726), subjects with locally advanced breast cancer who received axillary lymph node dissection and regional nodal radiotherapy (RT) were followed serially, between 2016 and 2021, before surgery, 4-8 weeks after surgery, and 6, 12, and 18 months after RT. Arm volume was measured by perometry, and lymphatic (dys) function was assessed by NIRF-LI.

RESULTS

By 18 months after RT, 30 of 42 study subjects (71%) developed mild-moderate BCRL (i.e., ≥ 5% arm swelling relative to baseline), all manifested by "dermal backflow" of lymph into lymphatic capillaries or interstitial spaces. Dermal backflow had an 83% positive predictive value and 86% negative predictive value for BCRL, with a sensitivity of 97%, specificity of 50%, accuracy of 83%, positive likelihood ratio of 1.93, negative likelihood ratio of 0.07, and odds ratio of 29.00. Dermal backflow appeared on average 8.3 months, but up to 23 months, before the onset of mild BCRL.

CONCLUSION

BCRL can be predicted by dermal backflow, which often appears months before arm swelling, enabling early treatment before the onset of edema and irreversible tissue changes.

Locoregional Management and Prognostic Factors in Breast Cancer Patients with Ipsilateral Internal Mammary and Axillary Lymph Node Involvement

PURPOSE

Breast cancer patients with ipislateral axillary and internal mammary (IM) lymph node involvement (cN3b) often forego IM node resection. Therefore, radiation is important for curative therapy. However, prognosis is not well-described in the era of modern systemic therapy and limited data exist to guide optimal locoregional treatment recommendations.

METHODS

We retrospectively reviewed 117 patients with non-metastatic cN3b breast cancer treated at our institution between 2014-2019. Staging included ultrasound evaluation of all regional nodal basins. All patients received neoadjuvant chemotherapy (NAC), resection of the breast primary and axillary nodal dissection, followed by adjuvant radiation to the breast/chest wall and regional nodes. Institutional guidelines recommend a 10 Gy boost to radiographically resolved nodes, and 16 Gy boost to unresolved nodes. Overall survival (OS), recurrence (RFS), locoregional (LRRFS), internal mammary (IMRFS), and distant metastasis free survival (DMFS) were evaluated with Kaplan Meier analysis. A multivariable model for RFS was constructed.

RESULTS

Median follow-up for 117 patients was 3.82 years. Median age at diagnosis was 46 years and 56 (48%) patients were receptor group ER+/HER2-. Mastectomy was performed in 96 (82%) of patients, 38 (32%) had biopsy confirmed IMC involvement, and 8 (7%) had IM node dissection. The median initial radiation dose was 50 Gy (range, 50-55) and IMC boost 10 Gy (range, 0-16). The 5-year OS, IMRFS, LRRFS, DMFS, and RFS were 74%, 98%, 89%, 68% and 67% respectively. On multivariable analysis, a clinical complete response (CR) of the IM nodes or pathologic ypN0 status had improved 5-year RFS with HR 0.24 (p=0.006) and HR 0.27 (p=0.05), respectively. Extranodal extension or lymphovascular invasion were associated with worse 5-year RFS with HR 4.13 (p=0.001) and HR 2.25 (p=0.04), respectively.

CONCLUSION

Multimodality therapy provides excellent locoregional control of 89% at 5 years for cN3b breast cancer patients. Adjuvant radiation yields a 5-year IMRFS of 98%. Clinical and pathologic response of IM nodes are independently prognostic for RFS.

Adoption of Ultrahypofractionated Radiation Therapy in Patients With Breast Cancer

Introduction

The first high-quality clinical trial to support ultrahypofractionated whole-breast irradiation (ultra-HF-WBI) for invasive early-stage breast cancer (ESBC) was published in April 2020, coinciding with the beginning of the COVID-19 pandemic. We analyzed adoption of ultra-HF-WBI for ductal carcinoma in situ (DCIS) and ESBC at our institution after primary trial publication.

Methods and Materials

We evaluated radiation fractionation prescriptions for all patients with DCIS or ESBC treated with WBI from March 2020 to May 2021 at our main campus and regional campuses. Demographic and clinical characteristics were extracted from the electronic medical record. Treating physician characteristics were collected from licensure data. Hierarchical logistic regression models identified factors correlated with adoption of ultra-HF-WBI (26 Gy in 5 daily factions [UK-FAST-FORWARD] or 28.5 Gy in 5 weekly fractions [UK-FAST]).

Results

Of 665 included patients, the median age was 61.5 years, and 478 patients (71.9%) had invasive, hormone-receptor-positive breast cancer. Twenty-one physicians treated the included patients. In total, 249 patients (37.4%) received ultra-HF-WBI, increasing from 4.3% (2 of 46) in March-April 2020 to a high of 45.5% (45 of 99) in July-August 2020 (P < .001). Patient factors associated with increased use of ultra-HF-WBI included older age (≥50 years old), low-grade WBI without inclusion of the low axilla, no radiation boost, and farther travel distance (P < .03). Physician variation accounted for 21.7% of variance in the outcome, with rate of use of ultra-HF-WBI by the treating physicians ranging from 0% to 75.6%. No measured physician characteristics were associated with use of ultra-HF-WBI.

Conclusions

Adoption of ultra-HF-WBI at our institution increased substantially after the publication of randomized evidence supporting its use. Ultra-HF-WBI was preferentially used in patients with lower risk disease, suggesting careful selection for this new approach while long-term data are maturing. Substantial physician-level variation may reflect a lack of consensus on the evidentiary standards required to change practice.

Outcomes After Breast Radiation Therapy in a Diverse Patient Cohort With a Germline BRCA1/2 Mutation

PURPOSE

BRCA1/2 pathogenic variant (PV) mutations confer radiation sensitivity preclinically, but there are limited data regarding breast cancer outcomes after radiation therapy (RT) among patients with documented BRCA1/2 PV mutations versus no PV mutations.

METHODS AND MATERIALS

This retrospective cohort study included women with clinical stage I-III breast cancer who received definitive surgery and RT and underwent BRCA1/2 genetic evaluation at the The University of Texas MD Anderson Cancer Center. Rates of locoregional recurrence (LRR), disease-specific death (DSD), toxicities, and second cancers were compared by BRCA1/2 PV status.

RESULTS

Of the 2213 women who underwent BRCA1/2 testing, 63% self-reported their race as White, 13.6% as Black/African American, 17.6% as Hispanic, and 5.8% as Asian/American Indian/Alaska Native; 124 had BRCA1 and 100 had BRCA2 mutations; and 1394 (63%) received regional nodal RT. The median follow-up time for all patients was 7.4 years (95% confidence interval [CI], 7.1-7.7 years). No differences were found between the groups with and without BRCA1/2 PV mutations in 10-year cumulative incidences of LRR (with mutations: 11.6% [95% CI, 7.0%-17.6%]; without mutations: 6.6% [95% CI, 5.3%-8.0%]; P = .466) and DSD (with mutations: 12.3% [95% CI, 8.0%-17.7%]; without mutations: 13.8% [95% CI, 12.0%-15.8%]; P = .716). On multivariable analysis, BRCA1/2 status was not associated with LRR or DSD, but Black/African American patients (P = .036) and Asians/American Indians/Alaska Native patients (P = .002) were at higher risk of LRR compared with White patients, and Black/African American patients were at higher risk of DSD versus White patients (P = .004). No in-field, nonbreast second cancers were observed in the BRCA1/2 PV group. Rates of acute and late grade ≥3 radiation-related toxicity in the BCRA1/2 PV group were 5.4% (n = 12) and 0.4% (n = 1), respectively.

CONCLUSIONS

Oncologic outcomes in a diverse cohort of patients with breast cancer who had a germline BRCA1/2 PV mutation and were treated with RT were similar to those of patients with no mutation, supporting the use of RT according to standard indications in patients with a germline BRCA1/2 PV mutation.

Breast Radiation Therapy-Related Treatment Outcomes in Patients With or Without Germline Mutations on Multigene Panel Testing

PURPOSE

Multigene panel testing has increased the detection of germline mutations in patients with breast cancer. The implications of using radiation therapy (RT) to treat patients with pathogenic variant (PV) mutations are not well understood and have been studied mostly in women with only BRCA1 or BRCA2 PVs. We analyzed oncologic outcomes and toxicity after adjuvant RT in a contemporary, diverse cohort of patients with breast cancer who underwent genetic panel testing.

METHODS AND MATERIALS

We retrospectively reviewed the records of 286 women with clinical stage I-III breast cancer diagnosed from 1995 to 2017 who underwent surgery, breast or chest wall RT with or without regional nodal irradiation, multigene panel testing, and evaluation at a large cancer center's genetic screening program. We evaluated rates of overall survival, locoregional recurrence, disease-specific death, and radiation-related toxicities in 3 groups: BRCA1/2 PV carriers, non-BRCA1/2 PV carriers, and patients without PV mutations.

RESULTS

PVs were detected in 25.2% of the cohort (12.6% BRCA1/2 and 12.6% non-BRCA1/2). The most commonly detected non-BRCA1/2 mutated genes were ATM, CHEK2, PALB2, CDH1, TP53, and PTEN. The median follow-up time for the entire cohort was 4.4 years (95% confidence interval, 3.8-4.9 years). No differences were found in overall survival, locoregional recurrence, or disease-specific death between groups (P > .1 for all). Acute and late toxicities were comparable across groups.

CONCLUSION

Oncologic and toxicity outcomes after RT in women with PV germline mutations detected by multigene pane testing are similar to those in patients without detectable mutations, supporting the use of adjuvant RT as a standard of care when indicated.

How should radiation be done for inflammatory breast cancer patients?-a narrative review of modern literature

OBJECTIVE

This review highlights the considerations of the radiation oncologist when managing patients with inflammatory breast cancer (IBC) as well as the radiation oncologist's role as a member of the multi-disciplinary team.

BACKGROUND

IBC makes up only 1-4% of all breast cancer diagnoses but incidence is increasing. IBC is diagnosed based on a constellation of clinical features, including the rapid onset of breast erythema and edema (peau d'orange) of one-third or more of the skin of the breast and with a palpable border to the edema. Most published IBC local-regional control rates are consistently lower than those observed in non-IBC, which the highlights the need for deliberate treatment techniques to maximize clinical outcomes.

METHODS

For this narrative review, we discuss the principles of radiation target delineation and dose escalation; highlight new findings in the local-regional management of IBC; provide a critical evaluation of the recent literature evaluating local-regional treatment of IBC; and offer a brief introduction to possible future directions regarding the optimal treatment and management of IBC based on our institutional experience.

CONCLUSIONS

IBC is an aggressive type of breast cancer that warrants multi-disciplinary care from breast surgical, medical, and radiation oncology. Several strategies exist to enhance the effect of radiation therapy (RT) on local-regional control, including hyperfractionation, use of bolus, increased total RT dose, and radiosensitizers, which are currently being tested in randomized trials. With an individualized patient approach, local-regional control rates are improving for IBC.

Five-Year Longitudinal Analysis of Patient-Reported Outcomes and Cosmesis in a Randomized Trial of Conventionally Fractionated Versus Hypofractionated Whole-Breast Irradiation

PURPOSE

There are limited prospective data on predictors of patient-reported outcomes (PROs) after whole-breast irradiation (WBI) plus a boost. We sought to characterize longitudinal PROs and cosmesis in a randomized trial comparing conventionally fractionated (CF) versus hypofractionated (HF) WBI.

METHODS AND MATERIALS

From 2011 to 2014, women aged ≥40 years with Tis-T2 N0-N1a M0 breast cancer who underwent a lumpectomy with negative margins were randomized to CF-WBI (50 Gray [Gy]/25 fractions plus boost) versus HF-WBI (42.56 Gy/16 fractions plus boost). At baseline (pre-radiation), at 6 months, and yearly thereafter through 5 years, PROs included the Breast Cancer Treatment Outcome Scale (BCTOS), Functional Assessment of Cancer Therapy-Breast (FACT-B), and Body Image Scale; cosmesis was reported by the treating physician using Radiation Therapy Oncology Group cosmesis values. Multivariable mixed-effects growth curve models evaluated associations of the treatment arm and patient factors with outcomes and tested for relevant interactions with the treatment arm.

RESULTS

A total of 287 patients were randomized, completing a total of 14,801 PRO assessments. The median age was 60 years, 37% of patients had a bra cup size ≥D, 44% were obese, and 30% received chemotherapy. Through 5 years, there were no significant differences in PROs or cosmesis by treatment arm. A bra cup size ≥D was associated with worse BCTOS cosmesis (P < .001), BCTOS pain (P = .001), FACT-B Trial Outcome Index (P = .03), FACT-B Emotional Well-being (P = .03), and Body Image Scale (P = .003) scores. Physician-rated cosmesis was worse in patients who were overweight (P = .02) or obese (P < .001). No patient subsets experienced better PROs or cosmesis with CF-WBI.

CONCLUSIONS

Both CF-WBI and HF-WBI confer similar longitudinal PROs and physician-rated cosmesis through 5 years of follow-up, with no relevant subsets that fared better with CF-WBI. This evidence supports broad adoption of hypofractionation with boost, including in patients receiving chemotherapy and in a population with a high prevalence of obesity. The associations of large breast size and obesity with adverse outcomes across multiple domains highlight the opportunity to engage at-risk patients in lifestyle intervention strategies, as well as to consider alternative radiation treatment regimens.

Proton Accelerated Partial Breast Irradiation: Clinical Outcomes at a Planned Interim Analysis of a Prospective Phase 2 Trial

PURPOSE

To perform a planned interim analysis of acute (within 12 months) and late (after 12 months) toxicities and cosmetic outcomes after proton accelerated partial breast irradiation (APBI).

METHODS AND MATERIALS

A total of 100 patients with pTis or pT1-2 N0 (≤3cm) breast cancer status after segmental mastectomy were enrolled in a single-arm phase 2 study from 2010 to 2019. The clinically determined postlumpectomy target volume, including tumor bed surgical clips and operative-cavity soft-tissue changes seen on imaging plus a radial clinical expansion, was irradiated with passively scattered proton APBI (34 Gy in 10 fractions delivered twice daily with a minimum 6-hour interfraction interval). Patients were evaluated at protocol-specific time intervals for recurrence, physician reports of cosmetic outcomes and toxicities, and patient reports of cosmetic outcomes and satisfaction with the treatment or experience.

RESULTS

Median follow-up was 24 months (interquartile range [IQR], 12-43 months). Local control and overall survival were 100% at 12 and 24 months. There were no acute or late toxicities of grade 3 or higher; no patients experienced fat necrosis, fibrosis, infection, or breast shrinkage. Excellent or good cosmesis at 12 months was reported by 91% of patients and 94% of physicians; at the most recent follow-up, these were 94% and 87%, respectively. The most commonly reported late cosmetic effect was telangiectasis (17%). The total patient satisfaction rate for treatment and results at 12 and 24 months was 96% and 100%, respectively. Patients' mean time away from work was 5 days (IQR, 2-5 days), and the median out-of-pocket cost was $700 (IQR, $100-$1600). The mean left-sided heart dose was 2 cGy (range, 0.2-75 cGy), and the mean ipsilateral lung dose was 19 cGy (range, 0.2-164 cGy).

CONCLUSIONS

Proton APBI is a maturing treatment option with high local control, favorable intermediate-term cosmesis, high treatment satisfaction, low treatment burden, and exceptional heart and lung sparing.

Exclusion of Men from Randomized Phase III Breast Cancer Clinical Trials

Male breast cancer treatment regimens are often extrapolated from female-based studies because of a paucity of literature analyzing male breast cancer. Using ClinicalTrials.gov, we analyzed breast cancer randomized clinical trials (RCTs) to determine which factors were associated with male-gender inclusion. Of 131 breast cancer RCTs identified, male patients represented 0.087% of the total study population, which is significantly less than the proportion of male patients with breast cancer in the U.S. (0.95%; p < .001). Twenty-seven trials included male patients (20.6%). Lower rates of male inclusion were seen in trials that randomized or mandated hormone therapy as part of the trial protocol compared with trials that did not randomize or mandate endocrine therapy (2.5% vs. 28.6% male inclusion; p < .001). It is imperative for breast cancer clinical trials to include men when allowable in order to improve generalizability and treatment decisions in male patients with breast cancer.

Abstract OT1-02-02: A pilot study to examine the feasibility of measuring CTC and inflammatory biomarker changes resulting from atorvastatin as adjuvant therapy in TNBC and TN-IBC patients with residual disease after neoadjuvant chemotherapy

Background: Patients who have TNBC or triple negative-IBC (TN-IBC) and do not achieve pathological complete response after neoadjuvant chemotherapy are at significant risk for distant relapse and death from recurrent disease. Apart from capecitabine, there are no proven adjuvant therapies that may improve these poor outcomes of patients with chemo-resistant tumors. Therefore, there is an unmet need for effective systemic therapy for this subset of patients with TNBC. Epidemiological evidence reveals that statin use after diagnosis is associated with improved breast cancer relapse-free survival and decreased mortality. However, direct evidence of in vivo mechanisms explaining this association are lacking. Preclinical studies using statins in breast cancer reveal pathways that statins can inhibit proliferation, stem cell self-renewal and metastatic potential.

Trial Design: This is a pilot study designed in 2 phases to assess feasibility of completion while providing a signal of efficacy in biomarker changes. In the first phase, we will follow the initial 30 patients who meet eligibility for atorvastatin treatment for the 2-year treatment window, or until disease recurrence. We will collect blood samples prior to, and during atorvastatin treatment for circulating tumor cells (CTCs), cytokine and inflammatory biomarker analyses. We defined a positive outcome as CTCs remaining non-detected at 6 months when baseline CTC is undetected, or a reduction in the number of CTCs at 6 months compared to baseline. If we observe a positive outcome among the initial 30 patients, then we will open the second phase of this study for an additional 50 patients. Here we will follow both patient cohorts who receive and not receive atorvastatin treatment to collect longitudinal data on biomarkers as a function of the natural history of TNBC to better understand the activity of atorvastatin.

Trial Eligibility: Patients with stage II-III TNBC who have residual cancer burden (RCB)-II or RCB-III or stage 3 TN-IBC with any amount of residual disease, and are not taking a statin or any other anti-lipidemic agent are candidates for the study. Patients must have adequate hematologic, organ, and cardiac function and must have recovered from the acute effects of any prior treatments. Baseline lipid profile will be assessed by a cardiologist to determine the patients’ eligibility to take atorvastatin based on current ACC/AHA guideline, and to select between moderate (20mg) or high intensity treatment (40mg).

Specific Aims: The primary objective is to determine the proportion of patients with undetectable CTCs at 6 months with and without atorvastatin therapy. Secondary objectives include correlation of baseline lipid profiles/lipid profile changes with 2 year-relapse free survival (RFS), CTC counts and inflammatory biomarkers.

Statistical Methods: The total estimated enrollment is 80 patients, including at least 5 treated with adjuvant capecitabine and at least 5 without adjuvant capecitabine. The study overall is powered with the assumption that 48 patients will receive atorvastatin and 32 will not, and this will allow us to estimate the percent of patients with negative CTCs at 6 months with a standard error not larger than 7% and 9%, respectively. All other analyses including inflammatory biomarkers and RFS differences between groups are exploratory and considered hypothesis-generating rather than conclusive.

Citation Format: Angela Alexander, Takeo Fujii, Michael C Stauder, Wendy A Woodward, James M Reuben, Yu Shen, Diane Liu, Sangeetha M Reddy, Vicente Valero, Susan C Gilchrist, Bora Lim, Anthony Lucci, Naoto T Ueno, Carlos H Barcenas. A pilot study to examine the feasibility of measuring CTC and inflammatory biomarker changes resulting from atorvastatin as adjuvant therapy in TNBC and TN-IBC patients with residual disease after neoadjuvant chemotherapy [abstract]. In: Proceedings of the 2019 San Antonio Breast Cancer Symposium; 2019 Dec 10-14; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2020;80(4 Suppl):Abstract nr OT1-02-02.

Association of Transforming Growth Factor β Polymorphism C-509T With Radiation-Induced Fibrosis Among Patients With Early-Stage Breast Cancer: A Secondary Analysis of a Randomized Clinical Trial

Importance

Whether genetic factors can identify patients at risk for radiation-induced fibrosis remains unconfirmed.

Objective

To assess the association between the C-509T variant allele in the promoter region of TGFB1 and breast fibrosis 3 years after radiotherapy.

Design, Setting, and Participants

This is an a priori-specified, prospective, cohort study nested in an open-label, randomized clinical trial, which was conducted in community-based and academic cancer centers to compare hypofractionated whole-breast irradiation (WBI) (42.56 Gy in 16 fractions) with conventionally fractionated WBI (50 Gy in 25 fractions) after breast-conserving surgery. In total, 287 women 40 years or older with pathologically confirmed stage 0 to IIA breast cancer treated with breast-conserving surgery were enrolled from February 2011 to February 2014. Patients were observed for a minimum of 3 years. Outcomes were compared using the 1-sided Fisher exact test and multivariable logistic regression.

Exposures

A C-to-T single-nucleotide polymorphism at position -509 relative to the first major transcription start site (C-509T) of the TGFB1 gene.

Main Outcomes and Measures

The primary outcome was grade 2 or higher breast fibrosis as assessed using the Late Effects Normal Tissue/Subjective, Objective, Medical Management, Analytic scale (range, 0 to 3) three years after radiotherapy.

Results

Among 287 women enrolled in the trial, TGFB1 genotype and 3-year radiotherapy-induced toxicity data were available for 174 patients, of whom 89 patients (51%) with a mean (SD) age of 60 (8) years had at least 1 copy of C-509T. Grade 2 or higher breast fibrosis was present in 12 of 87 patients with C-509T (13.8%) compared with 3 of 80 patients without the allele variant (3.8%) (absolute difference, 10.0%; 95% CI, 1.7%-18.4%; P = .02). The results of multivariable analyses indicated that only C-509T (odds ratio, 4.47; 95% CI, 1.25-15.99; P = .02) and postoperative cosmetic outcome (odds ratio, 7.09; 95% CI, 2.41-20.90; P < .001) were significantly associated with breast fibrosis risk.

Conclusions and Relevance

To date, this study seems to be the first prospective validation of a genomic marker for radiation fibrosis. The C-509T allele in TGFB1 is a key determinant of breast fibrosis risk. Assessing TGFB1 genotype may facilitate a more personalized approach to locoregional treatment decisions in breast cancer.

Trial Registration

ClinicalTrials.gov identifier: NCT01266642.

Safety and Efficacy of Panitumumab Plus Neoadjuvant Chemotherapy in Patients With Primary HER2-Negative Inflammatory Breast Cancer

Importance

Combining conventional chemotherapy with targeted therapy has been proposed to improve the pathologic complete response (pCR) rate in patients with inflammatory breast cancer (IBC). Epidermal growth factor receptor (EGFR) expression is an independent predictor of low overall survival in patients with IBC.

Objective

To evaluate the safety and efficacy of the anti-EGFR antibody panitumumab plus neoadjuvant chemotherapy in patients with primary human epidermal growth factor receptor 2 (HER2)-negative IBC.

Design, Setting, and Participants

Women with primary HER2-negative IBC were enrolled from 2010 to 2015 and received panitumumab plus neoadjuvant chemotherapy. Median follow-up time was 19.3 months. Tumor tissues collected before and after the first dose of panitumumab were subjected to immunohistochemical staining and RNA sequencing analysis to identify biomarkers predictive of pCR.

Intervention

Patients received 1 dose of panitumumab (2.5 mg/kg) followed by 4 cycles of panitumumab (2.5 mg/kg), nab-paclitaxel (100 mg/m2), and carboplatin weekly and then 4 cycles of fluorouracil (500 mg/m2), epirubicin (100 mg/m2), and cyclophosphamide (500 mg/m2) every 3 weeks.

Main Outcomes and Measures

The primary end point was pCR rate; the secondary end point was safety. The exploratory objective was to identify biomarkers predictive of pCR.

Results

Forty-seven patients were accrued; 7 were ineligible. The 40 enrolled women had a median age of 57 (range, 23-68) years; 29 (72%) were postmenopausal. Three patients did not complete therapy because of toxic effects (n = 2) or distant metastasis (n = 1). Nineteen patients had triple-negative and 21 had hormone receptor-positive IBC. The pCR and pCR rates were overall, 11 of 40 (28%; 95% CI, 15%-44%); triple-negative IBC, 8 of 19 (42%; 95% CI, 20%-66%); and hormone receptor-positive/HER2-negative IBC, 3 of 21 (14%; 95% CI, 3%-36%). During treatment with panitumumab, nab-paclitaxel, and carboplatin, 10 patients were hospitalized for treatment-related toxic effects, including 5 with neutropenia-related events. There were no treatment-related deaths. The most frequent nonhematologic adverse event was skin rash. Several potential predictors of pCR were identified, including pEGFR expression and COX-2 expression.

Conclusions and Relevance

This combination of panitumumab and chemotherapy showed the highest pCR rate ever reported in triple-negative IBC. A randomized phase 2 study is ongoing to determine the role of panitumumab in patients with triple-negative IBC and to further validate predictive biomarkers.

Trial Registration

ClinicalTrials.gov Identifier: NCT01036087.

Excellent Locoregional Control in Inflammatory Breast Cancer With a Personalized Radiation Therapy Approach

PURPOSE

Inflammatory breast cancer (IBC) has been characterized by high locoregional recurrence (LRR) rates even after trimodality therapy. We recently reported excellent locoregional control among patients treated since formal dedication of an IBC-specific clinic and research program in 2006. Institutionally, a standard twice-daily (BID) dose escalation regimen for all patients with IBC was de-escalated in select cases in 2006 after review demonstrated that young age, incomplete response to neoadjuvant therapy, and positive margins identified subsets with maximal benefit from dose escalation. We report local control and toxicity rates specific to BID versus once-daily (QD) radiation therapy approaches.

METHODS AND MATERIALS

From a prospectively collected database, we identified 103 patients with nonmetastatic IBC who received trimodality therapy at our institution from 2007 to 2015. Descriptive statistics were used to describe the study cohort and compare retrospectively extracted rates of radiation therapy-associated toxicity. The actuarial rate of LRR-free survival was analyzed using the Kaplan-Meier method.

RESULTS

The median follow-up is 3.6 years. Thirty-nine patients (37.9%) received postmastectomy radiation therapy (PMRT) to the chest wall and undissected regional lymphatics in QD fractions (median dose, 50.0 Gy in 25 fractions [fx]; median boost dose, 10.0 Gy in 5 fx) and 64 patients (62.1%) received BID PMRT (median dose, 51.0 Gy in 34 fx; median boost dose, 15.0 Gy in 10 fx). Crude rates of toxicity were not different between patients treated with QD or BID PMRT. Two BID patients (3.1%) and no QD patients (0.0%) experienced LRR (P = .53). The 3- and 5-year LRR-free survival were 95.1% and 100.0% for BID and QD patients, respectively (P = .25).

CONCLUSIONS

Tailoring radiation therapy to clinical risk factors was associated with excellent locoregional control. De-escalation of PMRT from BID to QD was not clearly associated with reduced toxicity compared with BID, although retrospective data collection may limit this comparison.

Three-Year Outcomes With Hypofractionated Versus Conventionally Fractionated Whole-Breast Irradiation: Results of a Randomized, Noninferiority Clinical Trial

PURPOSE

The adoption of hypofractionated whole-breast irradiation (HF-WBI) remains low, in part because of concerns regarding its safety when used with a tumor bed boost or in patients who have received chemotherapy or have large breast size. To address this, we conducted a randomized, multicenter trial to compare conventionally fractionated whole-breast irradiation (CF-WBI; 50 Gy/25 fx + 10 to 14 Gy/5 to 7 fx) with HF-WBI (42.56 Gy/16 fx + 10 to 12.5 Gy/4 to 5 fx).

PATIENTS AND METHODS

From 2011 to 2014, 287 women with stage 0 to II breast cancer were randomly assigned to CF-WBI or HF-WBI, stratified by chemotherapy, margin status, cosmesis, and breast size. The trial was designed to test the hypothesis that HF-WBI is not inferior to CF-WBI with regard to the proportion of patients with adverse cosmetic outcome 3 years after radiation, assessed using the Breast Cancer Treatment Outcomes Scale. Secondary outcomes included photographically assessed cosmesis scored by a three-physician panel and local recurrence-free survival. Analyses were intention to treat.

RESULTS

A total of 286 patients received the protocol-specified radiation dose, 30% received chemotherapy, and 36.9% had large breast size. Baseline characteristics were well balanced. Median follow-up was 4.1 years. Three-year adverse cosmetic outcome was 5.4% lower with HF-WBI ( Pnoninferiority = .002; absolute risks were 8.2% [n = 8] with HF-WBI v 13.6% [n = 15] with CF-WBI). For those treated with chemotherapy, adverse cosmetic outcome was higher by 4.1% (90% upper confidence limit, 15.0%) with HF-WBI than with CF-WBI; for large breast size, adverse cosmetic outcome was 18.6% lower (90% upper confidence limit, -8.0%) with HF-WBI. Poor or fair photographically assessed cosmesis was noted in 28.8% of CF-WBI patients and 35.4% of HF-WBI patients ( P = .31). Three-year local recurrence-free survival was 99% with both HF-WBI and CF-WBI ( P = .37).

CONCLUSION

Three years after WBI followed by a tumor bed boost, outcomes with hypofractionation and conventional fractionation are similar. Tumor bed boost, chemotherapy, and larger breast size do not seem to be strong contraindications to HF-WBI.

Inflammatory Breast Cancer: What to Know About This Unique, Aggressive Breast Cancer

Inflammatory breast cancer (IBC) is a rare form of breast cancer that accounts for only 2% to 4% of all breast cancer cases. Despite its low incidence, IBC contributes to 7% to 10% of breast cancer caused mortality. Despite ongoing international efforts to formulate better diagnosis, treatment, and research, the survival of patients with IBC has not been significantly improved, and there are no therapeutic agents that specifically target IBC to date. The authors present a comprehensive overview that aims to assess the present and new management strategies of IBC.

International Consensus on the Clinical Management of Inflammatory Breast Cancer from the Morgan Welch Inflammatory Breast Cancer Research Program 10th Anniversary Conference

National and international experts in inflammatory breast cancer (IBC) from high-volume centers treating IBC recently convened at the 10th Anniversary Conference of the Morgan Welch Inflammatory Breast Cancer Research Program at The University of Texas MD Anderson Cancer Center in Houston Texas. A consensus on the clinical management of patients with IBC was discussed, summarized, and subsequently reviewed. All participants at the conference (patients, advocates, researchers, trainees, and clinicians) were queried using the MDRing electronic survey on key management issues. A summary of the expert consensus and participant voting is presented. Bilateral breast and nodal evaluation, breast magnetic resonance imaging, positron emission tomography/computed tomography, and medical photographs were endorsed as optimal. Neoadjuvant systemic therapy, modified radical mastectomy and level I and II ipsilateral axillary node dissection, post-mastectomy radiotherapy, adjuvant targeted therapy and hormonal therapy as indicated, and delayed reconstruction were agreed-upon fundamental premises of standard non-protocol-based treatment for IBC. Consideration for local-regional therapy in de novo stage IV IBC was endorsed to provide local control whenever feasible. Variation across centers and special circumstances were discussed.

A component of lobular carcinoma in clinically lymph node-negative patients predicts for an increased likelihood of upstaging to pathologic stage III breast cancer

Purpose

Physical examination and diagnostic imaging are often less precise in determining the extent of disease in invasive lobular carcinoma (ILC) relative to nonlobular histologies. Anecdotally, surgical axillary evaluation frequently reveals positive lymph nodes in clinically N0 patients with ILC; however, few studies quantify the likelihood of finding unsuspected disease at the time of surgery. In this study, we evaluate whether the presence of lobular histology increases the incidence of surgical upstaging to pathologic stage IIIA or greater in patients with a clinically node-negative axilla and positive sentinel lymph node (SLN) biopsy.

Methods and materials

We examined patients from our institution between 1997 and 2009 treated specifically with mastectomy, SLN biopsy, and completion axillary lymph node dissection due to a positive SLN. For analysis, patients were grouped according to the presence of any lobular component on surgical pathology. The number of total positive lymph nodes, cancer stage, age, final tumor size, and ER/PR/HER2 status were assessed based on tumor histology.

Results

We evaluated 345 previously untreated women with clinical T0-T2 and N0 disease at the time of surgery. A total of 110 patients (32%) had a component of ILC on surgical pathology. In addition, 295 patients (85.5%) had ER + breast carcinoma, 243 (70.4%) had PR + disease, 56 (16.2%) were HER2 + , and 28 (8.1%) were triple negative. At the time of surgery, women with lobular disease were observed to have a greater number of positive lymph nodes (2.79 vs 2.26; P = .009) and were more frequently upstaged to at least pathologic stage IIIA compared with nonlobular patients (30.9% vs 17.4%; P = .007).

Conclusions

In this cohort, patients with a component of lobular carcinoma were more often surgically upstaged to pathologic stage IIIA or higher, which is a classical indication for postmastectomy radiation therapy. Our findings suggest that ILC is often more extensive than it appears clinically and has significant implications for management of patients with lobular carcinoma after the discovery of a positive SLN.

A 10-Year Experience with Mastectomy and Tissue Expander Placement to Facilitate Subsequent Radiation and Reconstruction

BACKGROUND

An integrated approach to skin sparing mastectomy with tissue expander placement followed by radiotherapy and delayed reconstruction was initiated in our institution in 2002. The purpose of this study was to assess the surgical outcomes of this strategy.

METHODS

Between September 2002 and August 2013, a total of 384 reconstructions had a tissue expander placed at the time of mastectomy and subsequently underwent radiotherapy. Rates and causes of tissue expander explantation before, during, and after radiotherapy, as well as tumor specific outcomes and reconstruction approaches, were collected.

RESULTS

Median follow-up after diagnosis was 5.6 (range 1.3-13.4) years. In the study cohort, 364 patients (94.8%) had stage II-III breast cancer, and 7 patients (1.8%) had locally recurrent disease. The 5-year rates of actuarial locoregional control, disease-free survival, and overall survival were 99.2, 86.1, and 92.4%, respectively. The intended delayed-immediate reconstruction was subsequently completed in 325 of 384 mastectomies (84.6% of the study cohort). Of the remaining 59 tissue expanders, 1 was explanted before radiotherapy, 1 during radiotherapy, and 7 patients (1.8%) were lost to follow-up. Fifty patients (13.0%) required tissue expander explantation after radiation and before their planned final reconstruction, primarily due to cellulitis. Nonetheless, the cumulative rate of completed reconstructions was 89.6%. The median time from placement of the tissue expander until reconstruction was 12 (interquartile range 9-15) months.

CONCLUSIONS

Tissue expander placement at skin-sparing mastectomy in patients who require radiotherapy appears to be a viable strategy for combining reconstruction and radiotherapy.

Impact of Statin Use on Outcomes in Triple Negative Breast Cancer

Purpose: We sought to investigate if the use of HMG Co-A reductase inhibitors (statins) has an impact on outcomes among patients with triple negative breast cancer (TNBC).

Methods: We reviewed the cases of women with invasive, non-metastatic TNBC, diagnosed 1997-2012. Clinical outcomes were compared based on statin use (defined as ever use during treatment vs. never use). We identified a subset of women for whom a 5-value lipid panel (5VLP) was available, including total cholesterol, low density lipoprotein, high density lipoprotein, very low density lipoprotein, and triglycerides. The Kaplan-Meier method was used to estimate median overall survival (OS), distant metastases-free survival (DMFS), and local-regional recurrence-free survival (LRRFS). A Cox proportional hazards regression model was used to test the statistical significance of prognostic factors.

Results: 869 women were identified who met inclusion criteria, with a median follow-up time of 75.1 months (range 2.4-228.9 months). 293 (33.7%) patients used statins and 368 (42.3%) had a 5VLP. OS, DMFS, and LRRFS were not significant based on statin use or type. Controlling for the 5VLP values, on multivariable analysis, statin use was significantly associated with OS (HR 0.10, 95% CI 0.01-0.76), but not with DMFS (HR 0.14, 95% CI 0.01-1.40) nor LRRFS (HR 0.10 95% CI 0.00-3.51).

Conclusions: Statin use among patients with TNBC is not associated with improved OS, although it may have a benefit for a subset of patients. Prospective assessment would be valuable to better assess the potential complex correlation between clinical outcome, lipid levels, and statin use.

Underuse of Radiation Therapy After Breast Conservation Surgery in Puerto Rico: A Puerto Rico Central Cancer Registry-Health Insurance Linkage Database Study

Purpose

To identify rates of postoperative radiation therapy (RT) after breast conservation surgery (BCS) in women with stage I or II invasive breast cancer treated in Puerto Rico and to examine the sociodemographic and health services characteristics associated with variations in receipt of RT.

Methods

The Puerto Rico Central Cancer Registry–Health Insurance Linkage Database was used to identify patients diagnosed with invasive breast cancer between 2008 and 2012 in Puerto Rico. Claims codes identified the type of surgery and the use of RT. Logistic regression models were used to examine the independent association between sociodemographic and clinical covariates.

Results

Among women who received BCS as their primary definitive treatment, 64% received adjuvant RT. Significant predictors of RT after BCS included enrollment in Medicare (odds ratio [OR], 2.14; 95% CI, 1.46 to 3.13; P ≤ .01) and dual eligibility for Medicare and Medicaid (OR, 1.61; 95% CI, 1.14 to 2.27; P < .01). In addition, it was found that RT was more likely to have been received in certain geographic locations, including the Metro-North (OR, 2.20; 95% CI, 1.48 to 3.28; P < .01), North (OR, 1.78; 95% CI, 1.20 to 2.64; P < .01), West (OR, 4.04; 95% CI, 2.61 to 6.25; P < .01), and Southwest (OR, 2.79; 95% CI, 1.70 to 4.59; P < .01). Furthermore, patients with tumor size > 2.0 cm and ≤ 5.0 cm (OR, 0.61; 95% CI, 0.40 to 0.93; P = .02) and those with tumor size > 5.0 cm (OR, 0.37; 95% CI, 0.15 to 0.92; P = .03) were found to be significantly less likely to receive RT.

Conclusion

Underuse of RT after BCS was identified in Puerto Rico. Patients enrolled in Medicare and those who were dually eligible for Medicaid and Medicare were more likely to receive RT after BCS compared with patients with Medicaid alone. There were geographic variations in the receipt of RT on the island.

Use of regional nodal irradiation and its association with survival for women with high-risk, early stage breast cancer: A National Cancer Database analysis

Purpose

The role of regional nodal irradiation (RNI) for patients with breast cancer remains controversial, particularly on the basis of nodal involvement. Using the National Cancer Database, we aimed to validate published data on whether expanding treatment fields from whole-breast irradiation (WBI) to encompass the regional nodes (WBI+RNI) affected overall survival (OS) for patients with node-positive (pN1-3) or high-risk node-negative (pN0) breast cancer treated with breast-conserving surgery and adjuvant chemotherapy.

Methods and materials

Women diagnosed with invasive breast cancer between 2004 and 2012 who met the selection criteria for the National Cancer Institute of Canada MA.20 trial were identified and stratified by receipt of RNI. Propensity score matching was used to compare 1:1 matched pairs of patients. Five-year OS was estimated using the Kaplan-Meier method. We used multivariate logistic regression to predict receipt of WBI+RNI and a multivariable Cox model to examine associations between patients' demographic, tumor, and treatment characteristics and OS using double robust estimation.

Results

Of 23,567 patients, 6,920 (29%) received WBI+RNI and 16,647 (71%) WBI. Median follow-up was 56 months. Use of WBI+RNI increased from 25.2% in 2004 to 32.2% in 2012 (P < .001). Patients receiving WBI+RNI more often had negative hormone-receptor status, ≥5 cm tumors and >1 involved node, and were not privately insured. For all patients, the 5-year OS rates were 90.8% with WBI+RNI versus 92.6% with WBI (P < .001). In the matched cohort (n = 10,922), the corresponding 5-year OS rates were 92% and 91.9% (P = .45), respectively. On multivariate analysis, WBI+RNI did not affect OS in the matched cohort (hazard ratio, 1.02; 95% confidence interval, 0.89-1.17, P = .76), regardless of pathologic nodal status.

Conclusions

In this large retrospective analysis, use of WBI+RNI did not affect 5-year OS rates for women with high-risk, early stage breast cancer undergoing breast-conserving surgery and adjuvant chemotherapy, regardless of nodal status, which confirms the findings of the MA.20 trial.

Inflammatory breast cancer: a proposed conceptual shift in the UICC-AJCC TNM staging system

In the absence of histological criteria that distinguish between inflammatory and non-inflammatory breast cancer, diagnosis of inflammatory breast cancer relies entirely on the existence of clinical criteria as outlined by the TNM classification. This classification restricts patients presenting with clinical criteria characteristic of inflammatory breast cancer to subcategory T4d, which immediately relegates all patients with non-metastatic inflammatory breast cancer to stage 3, regardless of tumour size or nodal spread. Patients who present with metastatic disease are consigned to stage 4, and the TNM classification does not distinguish patients on the basis of the presence of inflammatory criteria. Evidence by our group and others suggests that patients with inflammatory breast cancer have significantly reduced overall survival among those who present with distant metastasis at diagnosis (stage 4). In light of these results, this Personal View addresses whether the current TNM staging classification accurately represents a distinction between patients with inflammatory and those with non-inflammatory breast cancer.

Outcomes of Post Mastectomy Radiation Therapy in Patients Receiving Axillary Lymph Node Dissection After Positive Sentinel Lymph Node Biopsy

PURPOSE

We sought to determine the rate of postmastectomy radiation therapy (PMRT) among women treated with axillary lymph node dissection (ALND) after positive sentinel lymph node (SLN) biopsy results and to establish the effect of negative ALND results and PMRT on locoregional recurrence (LRR) and overall survival (OS).

METHODS AND MATERIALS

All patients were treated with mastectomy and ALND after positive SLN biopsy results. All patients had clinical N0 or NX disease at the time of mastectomy and received no neoadjuvant therapy. The presence of lymphovascular space invasion, presence of multifocality, number of positive SLNs and non-SLNs, clinical and pathologic stage, extranodal extension, age, and use of PMRT were evaluated for significance regarding the rates of OS and LRR.

RESULTS

A total of 345 patients were analyzed. ALND after positive SLN biopsy results was negative in 235 patients (68.1%), and a total of 112 patients (32.5%) received radiation therapy. On multivariate analysis, only pathologic stage III predicted for lower OS (hazard ratio, 3.32; P<.001). The rate of 10-year freedom from LRR was 87.9% and 95.3% in patients with positive ALND results and patients with negative ALND results, respectively. In patients with negative ALND results with ≥3 positive SLNs, the rate of freedom from LRR was 74.7% compared with 96.7% in those with <3 positive SLNs (P=.009). In patients with negative ALND results, ≥3 positive SLNs predicted for an increase in LRR on multivariate analysis (hazard ratio, 10.10; P=.034).

CONCLUSIONS

A low proportion of cT1-2, N0 patients with positive SLNs who undergo mastectomy receive PMRT after ALND. Even in this low-risk cohort, patients with ≥3 positive SLNs and negative ALND results are at increased risk of LRR and may benefit from PMRT.

Longitudinal analysis of patient-reported outcomes and cosmesis in a randomized trial of conventionally fractionated versus hypofractionated whole-breast irradiation

BACKGROUND

The authors compared longitudinal patient-reported outcomes and physician-rated cosmesis with conventionally fractionated whole-breast irradiation (CF-WBI) versus hypofractionated whole-breast irradiation (HF-WBI) within the context of a randomized trial.

METHODS

From 2011 to 2014, a total of 287 women with American Joint Committee on Cancer stage 0 to stage II breast cancer were randomized to receive CF-WBI (at a dose of 50 grays in 25 fractions plus a tumor bed boost) or HF-WBI (at a dose of 42.56 grays in 16 fractions plus a tumor bed boost) after breast-conserving surgery. Patient-reported outcomes were assessed using the Breast Cancer Treatment Outcome Scale (BCTOS), the Functional Assessment of Cancer Therapy-Breast, and the Body Image Scale and were recorded at baseline and 0.5, 1, 2, and 3 years after radiotherapy. Physician-rated cosmesis was assessed at the same time points. Outcomes by treatment arm were compared at each time point using a 2-sided Student t test. Multivariable mixed effects growth curve models assessed the effects of treatment arm and time on longitudinal outcomes.

RESULTS

Of the 287 patients enrolled, 149 were randomized to CF-WBI and 138 were randomized to HF-WBI. At 2 years, the Functional Assessment of Cancer Therapy-Breast Trial Outcome Index score was found to be modestly better in the HF-WBI arm (mean 79.6 vs 75.9 for CF-WBI; P = .02). In multivariable mixed effects models, treatment arm was not found to be associated with longitudinal outcomes after adjusting for time and baseline outcome measures (P≥.14). The linear effect of time was significant for BCTOS measures of functional status (P = .001, improved with time) and breast pain (P = .002, improved with time).

CONCLUSIONS

In this randomized trial, longitudinal outcomes did not appear to differ by treatment arm. Patient-reported functional and pain outcomes improved over time. These findings are relevant when counseling patients regarding decisions concerning radiotherapy. Cancer 2016. © 2016 American Cancer Society. Cancer 2016;122:2886-2894. © 2016 American Cancer Society.

Nomograms for Predicting Axillary Response to Neoadjuvant Chemotherapy in Clinically Node-Positive Patients with Breast Cancer

BACKGROUND

Many patients with clinically node-positive breast cancer receive neoadjuvant chemotherapy (NAC). Recent trials suggest the potential for limiting axillary surgery in patients who convert to pathologically node-negative disease. The authors developed a nomogram to predict axillary response to NAC in patients with cN1 disease that can assist clinicians in treatment planning.

METHODS

Patients with cT1-4N1M0 breast cancer who received NAC and underwent axillary lymph node dissection from 2001 through 2013 were identified (n = 584). Uni- and multivariate logistic regression analyses were performed to determine factors predictive of nodal conversion. A nomogram to predict the likelihood of nodal pathologic complete response (pCR) was constructed based on clinicopathologic variables and validated using an external dataset.

RESULTS

Axillary pCR was achieved for 217 patients (37 %). Patients presenting with high nuclear grade [grade 3 vs. 1, odds ratio (OR) 13.4], human epidermal growth factor receptor 2-positive (OR 4.7), estrogen receptor (ER)-negative (OR 3.5), or progesterone receptor-negative (OR 4.3) tumors were more likely to achieve nodal pCR. These factors, together with clinically relevant factors including presence of multifocal/centric disease, clinical T stage, and extent of nodal disease seen on regional nodal ultrasound at diagnosis were used to create nomograms predicting nodal conversion. The discrimination of the nomogram using ER+ status (>1 % staining) versus ER- status [area under the curve (AUC) 78 %] was improved slightly using the percentage of ER staining (AUC 78.7 %). Both nomograms were validated using an external cohort.

CONCLUSION

Nomograms incorporating routine clinicopathologic parameters can predict axillary pCR in node-positive patients receiving NAC and may help to inform treatment decisions.

Acute and Short-term Toxic Effects of Conventionally Fractionated vs Hypofractionated Whole-Breast Irradiation: A Randomized Clinical Trial

IMPORTANCE

The most appropriate dose fractionation for whole-breast irradiation (WBI) remains uncertain.

OBJECTIVE

To assess acute and 6-month toxic effects and quality of life (QOL) with conventionally fractionated WBI (CF-WBI) vs hypofractionated WBI (HF-WBI).

DESIGN, SETTING, AND PARTICIPANTS

Unblinded randomized trial of CF-WBI (n = 149; 50.00 Gy/25 fractions + boost [10.00-14.00 Gy/5-7 fractions]) vs HF-WBI (n = 138; 42.56 Gy/16 fractions + boost [10.00-12.50 Gy/4-5 fractions]) following breast-conserving surgery administered in community-based and academic cancer centers to 287 women 40 years or older with stage 0 to II breast cancer for whom WBI without addition of a third field was recommended; 76% of study participants (n = 217) were overweight or obese. Patients were enrolled from February 2011 through February 2014 and observed for a minimum of 6 months.

INTERVENTIONS

Administration of CF-WBI or HF-WBI.

MAIN OUTCOMES AND MEASURES

Physician-reported acute and 6-month toxic effects using National Cancer Institute Common Toxicity Criteria, and patient-reported QOL using the Functional Assessment of Cancer Therapy for Patients with Breast Cancer (FACT-B). All analyses were intention to treat, with outcomes compared using the χ2 test, Cochran-Armitage test, and ordinal logistic regression.

RESULTS

Of 287 participants, 149 were randomized to CF-WBI and 138 to HF-WBI. Treatment arms were well matched for baseline characteristics, including FACT-B total score (HF-WBI, 120.1 vs CF-WBI, 118.8; P = .46) and individual QOL items such as somewhat or more lack of energy (HF-WBI, 38% vs CF-WBI, 39%; P = .86) and somewhat or more trouble meeting family needs (HF-WBI, 10% vs CF-WBI, 14%; P = .54). Maximum physician-reported acute dermatitis (36% vs 69%; P < .001), pruritus (54% vs 81%; P < .001), breast pain (55% vs 74%; P = .001), hyperpigmentation (9% vs 20%; P = .002), and fatigue (9% vs 17%; P = .02) during irradiation were lower in patients randomized to HF-WBI. The rate of overall grade 2 or higher acute toxic effects was less with HF-WBI than with CF-WBI (47% vs 78%; P < .001). Six months after irradiation, physicians reported less fatigue in patients randomized to HF-WBI (0% vs 6%; P = .01), and patients randomized to HF-WBI reported less lack of energy (23% vs 39%; P < .001) and less trouble meeting family needs (3% vs 9%; P = .01). Multivariable regression confirmed the superiority of HF-WBI in terms of patient-reported lack of energy (odds ratio [OR], 0.39; 95% CI, 0.24-0.63) and trouble meeting family needs (OR, 0.34; 95% CI, 0.16-0.75).

CONCLUSIONS AND RELEVANCE

Treatment with HF-WBI appears to yield lower rates of acute toxic effects than CF-WBI as well as less fatigue and less trouble meeting family needs 6 months after completing radiation therapy. These findings should be communicated to patients as part of shared decision making.

TRIAL REGISTRATION

clinicaltrials.gov Identifier: NCT01266642.

Prognosis for patients with metastatic breast cancer who achieve a no-evidence-of-disease status after systemic or local therapy

BACKGROUND

This study sought to determine outcomes for patients with metastatic breast cancer (MBC) with no evidence of disease (NED) after treatment and to identify factors predictive of outcomes once the status of NED was attained.

METHODS

This study reviewed 570 patients with MBC who were consecutively treated between January 2003 and December 2005. Ninety patients (16%) attained NED, which was defined as a complete metabolic response on positron emission tomography or sclerotic healing of bone metastases on computed tomography or magnetic resonance imaging. The median follow-up for patients attaining NED was 100 months (range, 14-134 months).

RESULTS

The 3- and 5-year overall survival (OS) rates were 44% and 24%, respectively, for the entire group and 96% and 78%, respectively, for those attaining NED. According to a landmark analysis, NED status was significantly associated with survival at 2 (P < .001; hazard ratio [HR], 0.23; 95% confidence interval [CI], 0.16-0.34) and 3 years (P < .001; HR, 0.20; 95% CI, 0.14-0.30). From the time of NED, the median survival was 102 months (range, 14-134 months) with 5-year OS and progression-free survival (PFS) rates of 77% and 40%, respectively. According to a multivariate analysis, human epidermal growth factor receptor 2 positivity was significantly associated with OS in comparison with estrogen receptor positivity (P = .02; HR, 0.44; 95% CI, 0.21-0.90), and trastuzumab use was significantly associated with PFS (P = .007; HR, 0.48; 95% CI, 0.28-0.82). Thirty-one patients (34%) with NED remained in remission at the last follow-up.

CONCLUSIONS

MBC patients who attain the status of NED have significantly prolonged survival with a durable response to therapy. Ultimately, this study provides essential outcome data for clinicians and patients living with MBC.

Role of Ultrasonography of Regional Nodal Basins in Staging Triple-Negative Breast Cancer and Implications For Local-Regional Treatment

PURPOSE

We sought to determine the rate at which regional nodal ultrasonography would increase the nodal disease stage in patients with triple-negative breast cancer (TNBC) beyond the clinical stage determined by physical examination and mammography alone, and significantly affect the treatments delivered to these patients.

METHODS AND MATERIALS

We retrospectively reviewed the charts of women with stages I to III TNBC who underwent physical examination, mammography, breast and regional nodal ultrasonography with needle biopsy of abnormal nodes, and definitive local-regional treatment at our institution between 2004 and 2011. The stages of these patients' disease with and without ultrasonography of the regional nodal basins were compared using the Pearson χ(2) test. Definitive treatments of patients whose nodal disease was upstaged on the basis of ultrasonographic findings were compared to those of patients whose disease stage remained the same.

RESULTS

A total of 572 women met the study requirements. In 111 (19.4%) of these patients, regional nodal ultrasonography with needle biopsy resulted in an increase in disease stage from the original stage by physical examination and mammography alone. Significantly higher percentages of patients whose nodal disease was upstaged by ultrasonographic findings compared to that in patients whose disease was not upstaged underwent neoadjuvant systemic therapy (91.9% and 51.2%, respectively; P<.0001), axillary lymph node dissection (99.1% and 34.5%, respectively; P<.0001), and radiation to the regional nodal basins (88.2% and 29.1%, respectively; P<.0001).

CONCLUSIONS

Regional nodal ultrasonography in TNBC frequently changes the initial clinical stage and plays an important role in treatment planning.

Abstract P3-08-01: Gamma-ray induced mutagen sensitivity and overall survival in young women with breast cancer

Background:

Hypersensitivity to radiation has been shown to be a risk factor for the development of breast cancer. We aim to determine whether the same hypersensitivity predicts for adverse clinical outcomes in patients diagnosed with carcinoma of the breast.

Methods:

465 young, female, non-Hispanic white patients diagnosed with carcinoma of the breast at our institution from 1/1997 to 12/2005 were included in this study. All cases were histologically confirmed and all blood was drawn prior to any systemic or local therapy. Patient age, body mass index (BMI), menopause status, tumor laterality, AJCC stage, ER status, nuclear grade, and receipt of chemotherapy and radiation were extracted from patient medical records. A gamma-ray-induced mutagen sensitivity assay was performed using standard published methods to evaluate individual responses to radiation. The number of simple chromatid breaks per sample was counted from 50 well-spread metaphases. Each simple chromatid break was counted as a single break and each isochromatid break, exchange figure, or interstitial deletion as two breaks. The mean value of chromatid breaks per cell (b/c) was then calculated and recorded. Cox multivariable proportional hazards model was used to estimate the hazard ratio (HR) and 95% confidence interval (CI) for the association between b/c and overall survival.

Results:

A total of 402 patients had a b/c value recorded and were included in the final analysis. The patient median age was 46 years (range 22-55). 341 patients (84.8%) had invasive cancer and 253 patients (69.9%) had ER+ disease. AJCC stage distribution was stage 0 (15.2%), stage 1 (41.5%), stage 2 (33.5%), stage 3 (9.5%) and stage 4 (0.3%). The median follow-up for all patients was 97.2 months (interquartile range, IQR 83.3-119.6 months). The median b/c was 0.5 (IQR 0.38-0.62). The 5 and 10-year survival for all patients was 92.6% and 87.5%. A statistically significant decrease in 5 and 10-year overall survival was seen in patients with b/c greater than the median value of 0.5 (96.2% vs. 89.2%, p=.007 and 90.8% vs. 84.5%, p=.046, respectively). On multivariable analysis (MVA), age at diagnosis (HR 0.95, CI 0.91-0.99, p=.017), BMI (HR 1.07, CI 1.03-1.12, p=.003), ER status (HR= 0.31, CI 0.16-0.61, p=.01), AJCC stage (HR 1.91, CI 1.2-3.0, p=.006), and b/c level (HR 5.67, CI 1.5-18.2, p=.01) all predicted for overall survival. Excluding the 61 patients with in situ disease, there remains a significant difference in survival at both 5 and 7 years (95.5% vs. 88.5%, p=.017 and 93.5% vs. 86%, p=.021). A trend for decrease survival was seen at 10 years (p=0.09). On MVA for patients with invasive disease, age at diagnosis (HR=0.95, 95% CI 0.91-0.99, p=.026), BMI (HR=1.06, 95% CI 1.01-1.11, p=.023), AJCC stage (HR=2.41, CI 1.51-3.91, p=.0003), and ER status (HR=0.25, CI 0.12-0.49, p&lt; .0001) and b/c level (HR=3.76, CI 1.39-8.06, p=.012) were associated with overall survival.

Conclusions:

In this cohort of young, female, non-Hispanic white breast cancer patients, a greater b/c level predicted for decreased overall survival. The use of a gamma-ray-induced mutagen sensitivity assay may be prognostic and help select for those at increased risk of death.

Citation Format: Michael C Stauder, Simona F Shaitelman, Pamela K Allen, Abenaa M Brewster, Banu K Arun, Wendy A Woodward, Thomas A Buchholz, Li-E Wang. Gamma-ray induced mutagen sensitivity and overall survival in young women with breast cancer [abstract]. In: Proceedings of the Thirty-Seventh Annual CTRC-AACR San Antonio Breast Cancer Symposium: 2014 Dec 9-13; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2015;75(9 Suppl):Abstract nr P3-08-01.

The 21-gene recurrence score complements IBTR! Estimates in early-stage, hormone receptor-positive, HER2-normal, lymph node-negative breast cancer

Clinicians have traditionally used clinicopathological (CP) factors to determine locoregional recurrence (LR) risk of breast cancer and have generated the IBTR! nomogram to predict the risk of ipsilateral breast tumor recurrence (IBTR). The 21-gene recurrence score (RS) assay was recently correlated with LR in retrospective studies. The objective of this study was to examine the relationship between the RS and IBTR!. CP characteristics of 308 consecutive patients who underwent RS testing at our institution were examined. IBTR! was used to estimate the risk of 10-year IBTR. Descriptive statistics were used to compare the RS with the estimated IBTR!. Given a low event rate in this cohort, actual IBTR rates were not reported. Most patients had stage I/II (98%) and grade I/II (77%) disease. Median age was 54 years (range, 30–78). Median IBTR! without radiation therapy was 10% (mean, 12% [range, 4-43%]). RS was low (<18), intermediate (18–30), and high (>30) in 52% (n = 160), 40% (n = 123), and 8% (n = 25) patients. Overall, IBTR! did not correlate with RS (P = .77). We saw no correlation between RS and IBTR! in patients with less than (P = .32) or greater than (P = .48) a 10% risk of IBTR. Interestingly, Ki-67 expression correlated with both IBTR! (P = .019) and the RS (P = .002). Further study is warranted to determine if the RS can provide complementary biological information to CP factors in estimating the risk of LR. Prospective studies evaluating this association may potentially allow for individualized treatment decisions.

Late tumor pseudoprogression followed by complete remission after lung stereotactic ablative radiotherapy

Lung stereotactic ablative radiotherapy (SABR) has recently become more common in the management of patients with early-stage non-small cell lung cancer (NSCLC) and metastatic lung lesions who are not surgical candidates. By design, SABR is applied to small treatment volumes, using fewer but significantly higher dose fractions, and steep dose gradients. This treatment theoretically maximizes tumor cell death and decreases the risk of damage to the surrounding normal tissues. Local control rates for SABR in early stage lung cancer remain high. Since the numbers of primary tumor recurrences is small, some debate exists as to the appropriate definition of treatment failure. Controversies remain regarding the most appropriate interpretation of imaging tests obtained to evaluate treatment outcomes after lung SABR. Most definitions of progression include an increasing diameter of target lesion which can be problematic given the known mass-like consolidation seen on CT imaging after ablative therapy. Here, we present a case report illustrative of the pitfalls of relying solely on anatomic imaging to determine SABR treatment failure.

Lung stereotactic body radiotherapy using a coplanar versus a non-coplanar beam technique: a comparison of clinical outcomes

OBJECTIVES

To determine if lung stereotactic body radiotherapy (SBRT) using a coplanar beam technique was associated with similar outcomes as lung SBRT using a non-coplanar beam technique.

METHODS

A retrospective review was performed of patients undergoing lung SBRT between January 2008 and April 2011. SBRT was initially delivered with multiple non-coplanar, non-overlapping beams; however, starting in December 2009, SBRT was delivered predominantly with all coplanar beams in order to reduce treatment time and complexity.

RESULTS

This analysis included 149 patients; the median follow-up was 21 months. SBRT was delivered for primary (n = 90) or recurrent (n = 17) non-small cell lung cancer, or lung oligometastasis (n = 42). The most common dose (Gy)/fraction (fx) regimens were 48 Gy/4 fx (39%), 54 Gy/3 fx (37%), and 50 Gy/5 fx (17%). The beam arrangement was coplanar in 61 patients (41%) and non-coplanar in 88 patients (59%). In patients treated with 54 Gy/3 fx, the mean treatment times per fraction for the coplanar and non-coplanar cohorts were 10 and 14 minutes (p < 0.0001). Kaplan-Meier 2-year estimates of overall survival (OS), progression-free survival, and local control (LC) for the coplanar and non-coplanar cohorts were 65% vs. 56% (p = 0.30), 47% vs. 39% (p = 0.71), and 92% and 92% (p = 0.94), respectively. The 1-year estimates of grade 2-5 pulmonary toxicity for the coplanar and non-coplanar cohorts were 11% and 17%, respectively (p = 0.30). On multivariate analysis, beam arrangement was not significantly associated with OS, LC or pulmonary toxicity.

CONCLUSIONS

Patients treated with lung SBRT using a coplanar technique had similar outcomes as those treated with a non-coplanar technique.

Early-stage primary bone lymphoma: a retrospective, multicenter Rare Cancer Network (RCN) Study

PURPOSE

Primary bone lymphoma (PBL) represents less than 1% of all malignant lymphomas. In this study, we assessed the disease profile, outcome, and prognostic factors in patients with Stages I and II PBL.

PATIENTS AND METHODS

Thirteen Rare Cancer Network (RCN) institutions enrolled 116 consecutive patients with PBL treated between 1987 and 2008 in this study. Eighty-seven patients underwent chemoradiotherapy (CXRT) without (78) or with (9) surgery, 15 radiotherapy (RT) without (13) or with (2) surgery, and 14 chemotherapy (CXT) without (9) or with (5) surgery. Median RT dose was 40 Gy (range, 4-60). The median number of CXT cycles was six (range, 2-8). Median follow-up was 41 months (range, 6-242).

RESULTS

The overall response rate at the end of treatment was 91% (complete response [CR] 74%, partial response [PR] 17%). Local recurrence or progression was observed in 12 (10%) patients and systemic recurrence in 17 (15%). The 5-year overall survival (OS), lymphoma-specific survival (LSS), and local control (LC) were 76%, 78%, and 92%, respectively. In univariate analyses (log-rank test), favorable prognostic factors for OS and LSS were International Prognostic Index (IPI) score ≤1 (p = 0.009), high-grade histology (p = 0.04), CXRT (p = 0.05), CXT (p = 0.0004), CR (p < 0.0001), and RT dose >40 Gy (p = 0.005). For LC, only CR and Stage I were favorable factors. In multivariate analysis, IPI score, RT dose, CR, and CXT were independently influencing the outcome (OS and LSS). CR was the only predicting factor for LC.

CONCLUSION

This large multicenter retrospective study confirms the good prognosis of early-stage PBL treated with combined CXRT. An adequate dose of RT and complete CXT regime were associated with better outcome.

Excellent local control and survival after intraoperative and external beam radiotherapy for pediatric solid tumors: long-term follow-up of the Mayo Clinic experience

Use of external beam radiotherapy (EBRT) for pediatric solid malignancies is generally limited by the tolerance of normal tissue in developing organs. Intraoperative electron radiotherapy (IOERT) allows a more focal delivery of radiation dose because vital organs can be displaced and avoided during treatment. From February 1983 to July 2003, 20 children underwent IOERT for treatment of locally advanced or recurrent malignancies of the extremity or abdominopelvic area. All patients underwent EBRT and received IOERT doses of 7.5 to 25 Gy with 6-MeV to 15-MeV electrons. At a median follow-up of 11.6 years (range, 2.1 to 25.5 y), 13 patients (65%) were alive and without evidence of disease. Patients who underwent gross total resection had better local control (88% vs. 67%) and survival (71% vs. 33%) than patients for whom the resection was not achieved. Among 7 patients, 11 grade 3 toxicity events were reported. No grade >3 toxicities or second malignancies were observed during follow-up. Use of IOERT in combination with surgery and EBRT in management of pediatric solid malignancies provides excellent local control with reasonable toxicity. IOERT should be considered as an integral part of a multimodality regimen for pediatric solid malignancies, especially for patients with abdominopelvic malignancies.

Early pulmonary toxicity following lung stereotactic body radiation therapy delivered in consecutive daily fractions

BACKGROUND AND PURPOSE

Identify the incidence of early pulmonary toxicity in a cohort of patients treated with lung stereotactic body radiation therapy (SBRT) on consecutive treatment days.

MATERIAL AND METHODS

A total of 88 lesions in 84 patients were treated with SBRT in consecutive daily fractions (Fx) for medically inoperable non-small cell lung cancer or metastasis. The incidence of pneumonitis was evaluated and graded according to the NCI CTCAE v3.0.

RESULTS

With a median follow-up of 15.8 months (range 2.5-28.6), the median age at SBRT was 71.8 years (range 23.8-87.8). 47 lesions were centrally located and 41 were peripheral. Most central lesions were treated with 48Gy in 4 Fx, and most peripheral lesions with 54Gy in 3 Fx. The incidence of grade ≥ 2 pneumonitis was 12.5% in all patients treated, and 14.3% among the subset of patients treated with 54Gy in 3 Fx. A total of two grade 3 toxicities were seen as one grade 5 toxicity in a patient treated for recurrence after pneumonectomy.

CONCLUSIONS

Treating both central and peripheral lung lesions with SBRT in consecutive daily fractions in this cohort was well tolerated and did not cause excessive early pulmonary toxicity.

Stereotactic Body Radiation Therapy (SBRT) for Unresectable Pancreatic Carcinoma

Survival in patients with unresectable pancreatic carcinoma is poor. Studies by Mayo Clinic and the Gastrointestinal Tumor Study Group (GITSG) have established combined modality treatment with chemotherapy and radiation as the standard of care. Use of gemcitabine-based chemotherapy alone has also been shown to provide a benefit, but 5‑year overall survival still remains less than 5%. Conventional radiotherapy is traditionally delivered over a six week period and high toxicity is seen with the concomitant use of chemotherapy. In contrast, SBRT can be delivered in 3–5 days and, when used as a component of combined modality therapy with gemcitabine, disruption to the timely delivery of chemotherapy is minimal. Early single-institution reports of SBRT for unresectable pancreatic carcinoma demonstrate excellent local control with acceptable toxicity. Use of SBRT in unresectable pancreatic carcinoma warrants further investigation in order to improve the survival of patients with historically poor outcomes.

Immunogenicity of the hu14.18-IL2 immunocytokine molecule in adults with melanoma and children with neuroblastoma

PURPOSE

Immunocytokine (IC) hu14.18-IL2 is a fusion protein of humanized antidisialoganglioside (GD2) antibody (hu14.18) and interleukin (IL)-2. Sixty-one melanoma and neuroblastoma patients received IC in phase I/Ib studies. Patient sera were examined in ELISA to determine if an anti-IC antibody response occurred during treatment.

EXPERIMENTAL DESIGN

Serum was assayed for anti-idiotypic antibody (anti-id Ab) based on ability to bridge biotinylated hu14.18 to plate-bound hu14.18 and ability to inhibit binding of hu14.18 to GD2 antigen and/or murine anti-idiotypic antibody. ELISA was also used to detect antibodies to the Fc-IL2 end of hu14.18-IL2.

RESULTS

Thirty-two patients (52%) developed an anti-idiotypic antibody response (absorbance, >0.7) in the bridge ELISA. Twelve patients (20%) had an intermediate response, whereas 17 patients (28%) were negative (adsorbance, <0.3). The development of antibody to hu14.18-IL2 detected in the bridge ELISA was not related to the dose of hu14.18-IL2. Twenty of 33 adult patients (61%) demonstrated an anti-idiotypic antibody response based on binding inhibition ELISA. The anti-idiotypic response was inversely correlated (P < 0.002) with IC measured during the second course of treatment, indicating that development of anti-idiotypic antibodies interfered with detection of circulating hu14.18-IL2. All patients developed some inhibitory activity in the binding inhibition assay designed to detect antibodies to the Fc-IL2 region of the IC. There was a positive correlation between the peak serum level of IC in course 1 and the anti-Fc-IL2 response.

CONCLUSIONS

Patients treated with hu14.18-IL2 developed anti-idiotypic antibodies and anti Fc-IL2 antibodies. No association was seen between development of anti-IC antibodies and clinical toxicity.