Omission of Chest Wall/Scar Boost and Skin Bolus Does Not Increase Risk of Local Recurrence for Breast Cancer Patients

PURPOSE/OBJECTIVE(S)

For breast cancer patients receiving postmastectomy radiation (PMRT), little is known about the value of Chest Wall Boost (CWB) and Skin Bolus (SB) across different biological subtypes and patients with high-risk features.

MATERIALS/METHODS

We reviewed 2,917 charts of breast cancer patients treated with mastectomy between 2000-2020 at our institution. Only patients treated with PMRT were included. Patients with and without reconstruction were included. Reconstruction types included autologous or single-stage-direct-implant or two stages expanders/implant. PMRT was delivered with 3D conformal technique using photons and conventional fractionation (50-50.4 Gy in 25-28 fractions). CWB using enface electrons and 3-5 mm SB applied every other day were delivered at the discretion of the physician. Primary objectives were locoregional failure (LF) rates between CWB and No CWB groups; SB and No SB groups. Different subgroup analyses exploring the benefits of CWB and SB in different biological subtypes, patients with lymphovascular invasion (LVI+), positive margins (PM) and nipple sparing mastectomy (NSM) were conducted. Secondary objectives were toxicity of CWB and SB on different reconstruction outcomes and PMRT side effects. Logistic and cox regressions were used.

RESULTS

A total of 1,103 patients with an overall median follow-up of 7.8 years were available for analysis. Among the entire cohort, 55.4% received CWB, 76% received SB, 48% had LVI, 23% with PM, 41% with NSM, 67% with Luminal A, 15% with Luminal B, 7% with HER2 enriched and 11% with triple negative. The 10 years incidence of LF was 6.5% and 4.0% for CWB and NO CWB, respectively (HR 1.6, p = 0.1); and 5.6% and 5.1% for SB and NO SB respectively (HR 0.9, p = 0.8). Multivariable analysis of LF adjusted for LVI, ECE, grade, tumor size, number of malignant nodes, and biological subtype showed no association of CWB and SB with local control (HR:1.4, p = 0.2 and HR:0.9, p = 0.8), respectively. Subgroup analyses confirmed no association of CWB or SB with improved local control across different biological subtypes, (LVI+), PM and NSM patients. On multivariable level CWB significantly increased reconstruction complications (OR 2.3, p = 0.001, OR 1.7, p = 0.008) for infection/necrosis (I/N) and overall reconstruction failure (ORF), respectively; while SB did not (OR 1.1, p = 0.8, OR 1.0, p = 0.9) for I/N and ORF, respectively. 56 patients needed treatment break, 49 of them (87%) had SB. Both CWB and SB significantly increased the risk of higher grade radiation dermatitis (2-4) in the entire cohort OR 2.1 p = 0.01, and OR 2.3, p = 0.02 for CWB and SB, respectively.

CONCLUSION

CWB and SB did not improve local control across different biological subtypes, patients with LVI, Positive Margins and NSM. CWB significantly increased reconstruction complications and SB increased treatment breaks and radiation dermatitis. These findings do not support routine usage of CWB and SB.

Predictors of Locoregional Recurrence and Distant Failure after Neoadjuvant Chemotherapy Among Patients Treated with Mastectomy Versus Breast-Conserving Surgery

PURPOSE/OBJECTIVE(S)

To assess the patterns and predictors of locoregional recurrence (LRR) and distant failure (DF) after neoadjuvant chemotherapy among patients treated with mastectomy vs. breast-conserving surgery (BCS). Our secondary objective is to identify the predictors of failure among patients who achieved complete pathological response (pCR).

MATERIALS/METHODS

Between 2000 and 2021, 1111 patients who had unilateral breast cancer were identified retrospectively in a single-institution database of consecutive patients who were treated with mastectomy or BCS following neoadjuvant chemotherapy. Multivariable analysis was performed using Cox proportional hazards model to identify the independent predictors associated with LRR and DF. Subgroup analysis was performed to identify the predictive factors associated with LRR and DF among patients (n = 273) who achieved pCR.

RESULTS

The median follow-up for the entire cohort was 5.9 years (range, 1.2 months - 21.8 years). For LRR, the 10-year cumulative incidence was 12.9% and 5.8% in BCS and mastectomy cohorts, respectively (HR 1.7, p = 0.03). For DF, the 10-year cumulative incidence was 19.9% and 29.4% in BCS and mastectomy cohorts, respectively (HR 0.65, p = 0.005). In mastectomy patients, the following factors were associated with LRR: lymphovascular invasion (LVI) (HR 3.8, p< 0.001) and luminal A or B subtype (HR 0.32, p = 0.002), while in BCS patients, LVI (HR 2.3, p = 0.039), extracapsular extension (ECE) (HR 4.5, p< 0.001), and luminal A or B subtype (HR 0.24, p< 0.001) were associated with LRR. Regarding risk factors for DF: LVI (HR 1.97, p< 0.001), number of malignant lymph nodes (HR 1.06, p< 0.001), achieving pCR (HR 0.26, p = 0.001), and triple-negative disease (HR 1.8, p = 0.005) were identified in mastectomy patients, while LVI (HR 2.64, p = 0.002), number of malignant lymph nodes (HR 1.13, p< 0.001), ECE (HR 2.07, p = 0.03), and triple-negative disease (HR 2.9, p = 0.001) were associated with DF for BCS patients. Subgroup analysis for those who achieved pCR showed that cN0 stage (HR 0.16, p = 0.08) and undergoing mastectomy (HR 0.4, p = 0.07) were associated with a lower risk of recurrence, whether LRR or DF, in those patients.

CONCLUSION

Our study demonstrates that LVI, biological subtype, ECE, tumor response, and the number of malignant lymph nodes after neoadjuvant chemotherapy are significant independent predictors of LRR and/or DF. These findings highlight the therapeutic significance of incorporating further therapy to optimize outcomes in these patients. In addition, patients with clinical node-negative at initial presentation and those undergoing mastectomy are associated with a low risk of subsequent failure after achieving pCR. This hypothesis-generating data highlights the role of revisiting the surgical approach for patients achieving pCR after neoadjuvant chemotherapy.

Increased Complication Rates with Proton Therapy in Breast Cancer Patients with Immediate, Implant-Based Reconstruction: Single-Institution Comparative Effectiveness Analysis

PURPOSE/OBJECTIVE(S)

To compare the impact of protons vs. photons on breast reconstruction complications, for patients (pts) receiving postmastectomy radiation (PMRT) with either single-stage direct-to-implant (DTI) or two-staged expander/implant (TE/I).

MATERIALS/METHODS

We reviewed the charts of 578 pts who underwent immediate reconstruction followed by radiation at our institution between 2010 and 2020. Pts with implant-based reconstruction using either TE/I or DTI and PMRT delivery in the presence of the prosthesis were included. Pts enrolled in active ongoing clinical trials were excluded from the analysis. The photon group received 3D conformal or IMRT/VMAT treatment with a median dose of 50-50.4 Gy in 25 to 28 fractions. For proton pts, treatment was delivered mainly with pencil beam scanning technique (PBS); few pts received passively scattered proton spread-out Bragg peak (SOBP). The complications were defined as infection/skin necrosis (I/N) requiring operative debridement, capsular contracture (CC) necessitating capsulotomy, and overall implant failure (ORF) as the removal of the permanent implant irrespective of replacement outcomes (i.e., with and without salvage reconstruction). We fit inverse-probability weighted cumulative incidence curves to adjust for confounding and non-random loss to follow-up. Various sensitivity analyses were conducted.

RESULTS

Four hundred ninety-five pts were available for the final analysis with an overall median follow-up of 55 months. 66 (13%) received protons, of which14 were treated with SOBP protons. 137 (28%) and 256 (56%) received photons with and without chest wall boost (CWB), respectively. The 5-year inverse probability-weighted risk of CC post-PMRT was 31% for protons vs. 10% for photons (RR:3.09, 95% CI: 1.77, 5.40). The 5 years ORF risk was 35.6% in protons compared to 22.7% in photons pts (RR: 1.57; 95% CI 1.0, 2.48). Hazard ratios from the adjusted Cox models were 3.79 (p<0.001) for CC and 2.05 (p<0.01) for ORF. No difference in I/N was noted between protons and photons pts. Sensitivity analysis showed that protons significantly increased CC risk vs photons both with CWB (HR:3.56, P<0.001) and without CWB (HR:3.9, p<0.001). Similar outcomes were observed with ORF, where protons increased the rate of ORF compared to photons, irrespective of CWB (HR 1.8, p = 0.038 with CWB; HR 2.4, p = 0.004 without CWB). No differences between PBS and SOBP proton techniques were noted.

CONCLUSION

Compared to photons, proton therapy increases the risk of capsular contracture requiring surgical intervention and hence overall reconstruction failure. This data should inform discussions about the risks and benefits of protons in patients with reconstruction, while awaiting mature data from ongoing clinical trials (RADCOMP) utilizing protons for breast cancer.

Is it the Type of Axillary Surgery or the Number of Removed Lymph Nodes That Increases the Risk of Breast Cancer Related Lymphedema (BCRL)? Results from a Prospective Screening Trial

PURPOSE/OBJECTIVE(S)

Axillary surgery has been identified as the main risk factor for BCRL regardless the delivery of regional nodal radiation (RLNR). Yet it remains unknown if it is the type of axillary surgery or the number of removed lymph nodes (LN) that increases BCRL risks.

MATERIALS/METHODS

Between 2008 and 2021, 3,350 patients (pts) who received surgery for breast cancer were enrolled in a lymphedema screening trial. Patients with bilateral breast cancer or without axillary surgery were excluded. Perometry was used to assess limb volume preoperatively in all patients. BCRL was defined as a ≥10% relative arm-volume increase arising >3 months postoperatively. The cohort was divided by axillary surgery type: axillary lymph node dissection (ALND) and sentinel lymph node biopsy (SLNB). Radiation was delivered using 3D conformal technique and RLNR was defined as the usage of anterior supraclavicular field. No hypofractionation was used and doses ranged between 50 and 50.4 Gy in 25-28 fractions. Multivariable Cox proportional hazard models compared the cumulative incidence of BCRL and local failure between different patient groups.

RESULTS

After applying inclusion criteria, 2,623 pts were available with overall median follow-up s of 6.1 years. Of the entire cohort, 709 (27%) had ALND with a median of 16 LN removed, while 1,914 (73%) received SLNB only with a median of 2 LN removed. The median number of malignant LN and patients receiving RLNR was higher in ALND group compared to SLNB only group. Frequency distribution analysis showed that the main overlap between ALND and SLNB only groups happen in the range of 3-11 LN removed. Therefore, the primary analysis focused only on pts with 3-11 LN across both groups (n = 690: ALND n = 140, SLNB n = 550). The multivariable model adjusted for BMI, RLNR, age and breast surgery showed that in this group with 3-11 LN removed in both cohorts, ALND remained significantly associated with BCRL (HR: 4.2, p<0.0001). Separate analyses for the entire SLNB only group and ALND groups were conducted to evaluate if the BCRL risk increases per each removed LN within the same axillary surgery group. The multivariable analysis for SLNB only pts(N = 1,914) showed that for each LN removed the risk of BCRL did not increase significantly (HR:1.06, p = 0.3), similarly for ALND group (N = 709) for each LN removed (HR:1.02, p = 0.08). For pts with pathologic N2-N3 disease and clinical node negative without neoadjuvant chemotherapy receiving ALND, the number of LN removed did not significantly improve neither Local control (HR:1.02, p = 0.8) nor distant disease survival (HR:1.01, p = 0.6).

CONCLUSION

ALND procedure per se is the main risk factor for BCRL not the number of LNs removed. For high-risk pts with >N2 disease, aggressive ALND did not improve tumor outcome. De-escalation with targeted axillary sampling followed by RLNR should be evaluated. Future lymphedema research should account for type of axillary surgery instead of number of LNs removed as a factor. (NCT01521741).

Comparison between Pre-Pectoral and Post-Pectoral Implant Reconstruction and Different Radiation Modalities on Breast Reconstruction Complications

PURPOSE/OBJECTIVE(S)

Single Stage direct to implant (DTI) is a rising reconstruction approach. It has been speculated that prepectoral implant placement reduces reconstruction complications as well as using newer postmastectomy radiation (PMRT) modalities as protons. Largest series in this topic included 350 DTI patients with less than 30 patients receiving PMRT.

MATERIALS/METHODS

We reviewed the charts of 2,187 patients (pts) who underwent mastectomy and reconstruction at our institution between 2000 and 2020. Pts only receiving DTI with and without PMRT were included. PMRT was delivered either with 3D conformal photon +/- chest wall electron boost (CWB) or proton therapy mainly with pencil beam scanning. All pts received conventional fractionation (50-50.4 Gy in 25-28 fractions). Patients on active protons clinical trials were excluded. Primary endpoints were reconstruction complications defined as infection/necrosis (I/N) requiring debridement; capsular contracture (CC) requiring capsulotomy and overall reconstruction failure (ORF: removal of permanent implant for any complication with and without salvage reconstruction). Subgroup analysis for pts receiving PMRT was done to explore impact of proton and photons on complications. Logistic and cox regression were used.

RESULTS

Eight hundred nine pts received DTI, with an overall median follow-up of 6.2 years. Among the entire cohort, 78/809 (9.7%) had prepectoral implants while the rest had subpectoral implants with and without alloderm support. Of the entire cohort 391/809 (48.5%) received PMRT, among those 43/391 (11%) received protons. The 5 years cumulative incidence of CC was 8.5% and 6.6% among prepectoral vs subpectoral implants (HR = 1.2, p = 0.7). The 5 years cumulative incidence of ORF was 32.2% and 28.2% among prepectoral vs subpectoral implants (HR 1.1, p = 0.6). For pts receiving PMRT, the 5 years cumulative incidence of CC were 26.0% and 8.6% among protons vs photons (HR 3.7, p < 0.0005). The 5 years cumulative incidence of ORF were 38.2% and 30.1% among protons vs photons (HR 1.4, p = 0.2). Multivariable logistic regression analysis accounting for BMI, smoking history, diabetes, and PMRT showed no significant difference between prepectoral implants versus subpectoral coverage for CC (OR = 0.7, p = 0.5), and for ORF (OR = 0.9, p = 0.8). Subgroup multivariable analysis for those receiving PMRT only showed protons compared to photons significantly increased the risk of CC (OR = 5.3, p < 0.0001) and ORF (OR = 2.1, p = 0.03). No significant difference in I/N was noted between photons and protons or between prepectoral and subpectoral pts.

CONCLUSION

For breast cancer patients receiving single stage direct to implant reconstruction with and without PMRT, prepectoral implant placement did not reduce the risk of complications. Proton therapy compared to photons significantly increased the risk of capsular contracture requiring capsulotomies and significantly increased overall reconstruction failures with implants removal.

Comparison of perometry-based volumetric arm measurements and bioimpedance spectroscopy for early identification of lymphedema in a prospectively-screened cohort of breast cancer patients

Breast cancer-related lymphedema (BCRL) affects more than one in five women treated for breast cancer, and women remain at lifelong risk. Screening for BCRL is recommended by several national and international organizations for women at risk of BCRL, and multiple methods of objective screening measurement exist. The goal of this study was to compare the use of perometry and bioimpedance spectroscopy (BIS) for early identification of BCRL in a cohort of 138 prospectivelyscreened patients. At each screening visit, a patient's relative volume change (RVC) from perometer measurements and change in L-Dex from baseline (ΔL-Dex) using BIS was calculated. There was a negligible correlation between RVC and ΔL-Dex (r=0.195). Multiple thresholds of BCRL were examined: RVC ≥5% and ≥10% as well as and ΔL-Dex ≥6.5 and ≥10. While some patients developed an elevated RVC and ΔL-Dex, many demonstrated elevations in only one threshold category. Moreover, the majority of patients with RVC ≥5%, ΔL-Dex ≥6.5, or ΔL-Dex ≥10 regressed to non-elevated measurements without intervention. These findings suggest a role for combining multiple screening methods for early identification of BCRL; furthermore, BCRL diagnosis must incorporate patient symptoms and clinical evaluation with objective measurements obtained from techniques such as perometry and bioimpedance spectroscopy.

Methods for quantifying breast cancer-related lymphedema in patients undergoing a contralateral prophylactic mastectomy

Patients treated for breast cancer are at risk of developing breast cancer-related lymphedema (BCRL). A significant proportion of patients treated for breast cancer are opting to undergo a contralateral prophylactic mastectomy (CPM). Currently, it remains unclear as to whether the relative volume change (RVC) equation may be used as an alternative to the weight adjusted change (WAC) equation to quantify BCRL in patients who undergo CPM. In order to simplify BCRL screening, our cohort of patients who underwent a CPM (n=310) was matched by BMI to a subset of patients who underwent unilateral breast surgery (n=310). Arm volume measurements were obtained via an optoelectronic perometer preoperatively, postoperatively, and in the follow-up setting every 6-12 months. The correlation of ipsilateral RVC and WAC values for those who underwent bilateral surgery was calculated (r=0.60). Contralateral WAC values for patients in both cohorts were compared, and there was no significant difference between the two distributions in variance (p=0.446). The RVC equation shows potential to be used to quantify ipsilateral postoperative arm volume changes for patients who undergo a CPM. However, a larger trial in which RVC and WAC values are prospectively assessed is needed.

Abstract P3-14-02: Upper extremity edema in the at-risk arm among patients receiving PI3K/mTOR/CDK4/6 inhibitors for metastatic breast cancer

Background: Targeted therapies, including mTOR and CDK 4/6 inhibitors, have changed the landscape of management of hormone receptor-positive (HR+) metastatic breast cancer (MBC). These therapies have shown significant improvement in progression-free survival and are generally well-tolerated. In pre-clinical models, modulation of the PI3K/mTOR pathway can impede lymphoangiogenesis resulting in capillary leakage. In this study, we examined the impact of PI3K, mTOR, and CDK 4/6 inhibitors in the development of upper extremity edema (UEE) in the at-risk arm for breast cancer-related lymphedema (BCRL) in patients with MBC.

Methods: We conducted a retrospective chart review of patients treated with PI3K/mTOR/CDK4/6 inhibitors for MBC. Clinicopathologic data including age, body-mass index (BMI), specific pathway targeted, treatment duration, and presence of edema were recorded. Characteristics of treatment including surgery type and laterality, nodal surgery, radiation regimen, and tumor subtype were also collected.

Results: Among patients with MBC treated with PI3K, mTOR, and/or CDK 4/6 inhibitors (N = 160), the incidence of edema that developed after initiation of the targeted therapy was 11.3% (18/160) for UEE and 31.9% (51/160) for edema in any anatomical location. 50.0% (11/22) of patients treated with a PI3K-a inhibitor, 32.6% (14/43) of patients treated with an mTOR inhibitor, and 33.3% (8/24) of patients treated with a CDK4/6 inhibitor alone developed peripheral edema following initiation of the respective targeted therapy. Further, swelling developed in the at-risk upper extremity after C1D1 in 13.6% (3/22) patients treated with a PI3K-α inhibitor exclusively, 7.0% (3/43) treated with an mTOR inhibitor exclusively, and in 12.5% (3/24) treated with a CDK4/6 inhibitor exclusively. Of the 42 patients treated with a CDK4/6 inhibitor in combination with either an mTOR inhibitor, aromatase inhibitor, or an ER-binding promoter, the incidence of UEE in the at-risk upper extremity after C1D1 was 18.8% (6/32), 0.0% (0/7), and 0.0% (0/3) respectively. In multivariate logistic regression analysis, both therapy with PI3K-a inhibitors (OR: 3.22; p = 0.049) and a relative decrease in serum albumin after 3 months of treatment (OR: 3.35, p = 0.024) increased the risk of developing peripheral edema; however, duration of therapy, and nodal surgery were not significant risk factors. Upon stratification of this cohort by number of BCRL-related risk factors, the incidence of BCRL was 18.3%, 39.5%, and 83.3% in women with one, two, or three BCRL-related risk factors, respectively.

Conclusions: PI3K, mTOR, and CDK 4/6 inhibitors may influence the development of UEE, which may cause or exacerbate progression of BCRL in at-risk arm among patients with MBC. Further research is needed to prospectively evaluate these novel findings as well as elucidate physiologic and clinical impacts of these therapies on peripheral edema and BRCL. Moreover, it is crucial to understand the role of close monitoring for the development or progression of peripheral edema or BCRL to ensure early detection and treatment, thus potentially minimizing the negative impacts on the quality of life of patients with MBC.

Citation Format: Daniell KM, Bardia A, Sun F, Brunelle CL, Gillespie TC, Sayegh HE, Naoum GE, Isakoff SJ, Juric D, Taghian AG. Upper extremity edema in the at-risk arm among patients receiving PI3K/mTOR/CDK4/6 inhibitors for metastatic breast cancer [abstract]. In: Proceedings of the 2018 San Antonio Breast Cancer Symposium; 2018 Dec 4-8; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2019;79(4 Suppl):Abstract nr P3-14-02.

Abstract P2-11-03: Not presented

This abstract was not presented at the symposium.

Abstract P2-11-04: Not presented

This abstract was not presented at the symposium.

Abstract P5-13-09: Development and implementation of a patient-centered, nurse practitioner-led survivorship intervention for breast cancer

This abstract was withdrawn by the authors.

Abstract PD4-03: Chemotherapy-related risk factors associated with lymphedema in breast cancer patients: Should repeated ipsilateral arm infusions be avoided?

Background: Breast Cancer-Related Lymphedema (BCRL) is a chronic, iatrogenic condition that can occur after damage to the lymphatic system during surgery (sx) or radiation, precipitating edema of the arm, breast, or trunk. BCRL risk-reduction education is an essential component of clinical care, and practitioners often advise patients (pts) to avoid needle punctures on the treated arm when possible. There is, however, a lack of substantial scientific evidence to lessen patient distress. Considering the common use of chemotherapy (CT) agents in this population, we assessed whether repeated skin punctures on the ipsilateral arm for CT infusions increased the risk of BCRL compared to CT via central lines in a large, prospective cohort of breast cancer (BC) pts.

Methods: We prospectively screened 630 pts with unilateral (487) or bilateral (143) BC sx receiving neoadjuvant (NAC) and/or adjuvant CT (AdjCT) for arm lymphedema (defined as volume change ≥10%) at our hospital from 2005–16. Pts were measured with a perometer pre-operatively and at 3–7 month follow-up intervals. Clinicopathologic and treatment (tx)-related characteristics, including details on CT regimen and the method of intravenous (IV) CT administration [peripheral IV catheters (PIVCs), central venous access devices (CVADs), peripherally inserted central catheters (PICCs)] were obtained by chart review. Cox proportional hazard analyses were applied to ascertain the risk of BCRL associated with these factors.

Results: The median post-op follow-up was 44 months. Of the 630 pts, 40% underwent axillary lymph node dissection (ALND), 60% underwent sentinel lymph node biopsy (SLNB) or no nodal sx, 16% and 89% received NAC or AdjCT, respectively. CT was administered via PIVCs inserted in the hand/arm for 59%, via CVADs or PICCs for 26%, and via both PIVCs at least once and CVADs/PICCs for 15%. The 2-yr cumulative incidence of BCRL was 12% (95% CI 9.9-15.2%). Multivariable regression results indicated that pts with both peripheral IV infusions on the arm and implanted CVADs did not have a higher risk of BCRL (HR(95% CI)=1.4(0.6-3.6)) than pts who received CT via CVADs only (1.7(0.7-3.8)). The overall number of NAC (p=0.24;0.9(95% CI 0.8-1.1)) or AdjCT cycles (p=0.78;1.0(0.9-1.1)) was not associated with BCRL, nor was the number of peripheral IV infusions (p=0.17;1.0(1.0-1.1)). BMI &gt;30 (p&lt;0.0001;3.4(1.9-6.0)) and number of positive lymph nodes (p=0.02;3.2(1.3-8.1)) were significantly associated with BCRL. Among those with PIVCs, pts with bilateral SLNB/ALND were more likely to develop BCRL than pts with unilateral sx (p&lt;0.01;5.0(1.9-13.4)). Only 38% of the 32 bilateral pts with BCRL received at least one peripheral IV infusion on their ipsilateral arm.

Conclusion: Results suggest that repeated skin punctures on the ipsilateral arm for CT infusions do not significantly increase the risk for BCRL compared to implanted CVADs, nor does the overall number of CT cycles. As survivors may be concerned about the risk of developing BCRL following sx and tx, healthcare practitioners should strive to mitigate pt worry during and well beyond the course of tx, educating pts about the lifestyle risk exposures for BCRL and precautionary guidelines not being definitive.

Citation Format: Asdourian MS, Rao SR, Skolny MN, Salama L, Brunelle C, Seward C, Taghian AG. Chemotherapy-related risk factors associated with lymphedema in breast cancer patients: Should repeated ipsilateral arm infusions be avoided? [abstract]. In: Proceedings of the 2016 San Antonio Breast Cancer Symposium; 2016 Dec 6-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2017;77(4 Suppl):Abstract nr PD4-03.

Abstract P4-12-04: Breast cancer subtype, age and lymph node status as predictors of local recurrence following breast-conserving therapy

Purpose/Objectives: Advances in breast-conserving therapy (BCT) have yielded local control rates comparable or superior to those of mastectomy. Here, we sought to identify risk factors associated with isolated local recurrence (LR) following BCT.

Materials/Methods: This study included a multi-institutional cohort of 2,233 consecutive breast cancer patients who underwent BCT between 1998 and 2007. Patient characteristics and disease parameters were stratified by age, subtype and nodal status. Biologic subtype was approximated by receptor status and tumor grade. No patients received HER2/neu-directed therapy. The association of clinicopathologic features with LR was evaluated using Cox proportional hazards regression models.

Results: At a median follow-up of 106 months, 69 LR events (3.1%) were observed. Among the overall cohort, 10-year freedom from LR was 95.9%. On univariate Cox regression analysis, risk factors associated with LR included subtype other than luminal A (hazard ratio [HR] for luminal B = 3.01, HER2 = 6.29, triple negative [TNBC] = 4.72; p&lt;0.001 for each), younger age (HR of oldest versus youngest quartile = 0.43; p=0.005), regional lymph node involvement (HR for 4-9 involved nodes = 3.04; &gt;9 nodes = 5.82; p&lt;0.01 for each), positive resection margins (HR = 2.43; p=0.005), and high-grade disease (HR = 5.37; p &lt;0.001). Presence of LVI (HR = 1.56; p=0.06) or 1-3 involved nodes (HR = 1.55; p=0.07) approached significance. Multivariate Cox regression demonstrated an association with LR among those with non-luminal A subtypes (HR for luminal B = 2.64, HER2 = 5.42, TNBC = 4.32; p&lt;0.001 for each), younger age (HR for age &gt;50 = 0.56; p=0.01), and any nodal disease (HR=1.06 per involved node; p&lt;0.004).

Conclusions: BCT yields favorable outcomes for the large majority of patients, although increased LR was observed among those with non-luminal A subtypes, younger age, and increasing lymph node involvement. Risk factors for LR following BCT appear to be converging with those following mastectomy in the current era.

Citation Format: Braunstein LZ, Taghian AG, Niemierko A, Salama L, Capuco A, Wong JS, Punglia RS, Bellon JR, MacDonald SM, Harris JR. Breast cancer subtype, age and lymph node status as predictors of local recurrence following breast-conserving therapy [abstract]. In: Proceedings of the 2016 San Antonio Breast Cancer Symposium; 2016 Dec 6-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2017;77(4 Suppl):Abstract nr P4-12-04.

Abstract OT2-5-01: The PREDICT study (prospective, randomized early detection and intervention after breast cancer - Treatment, for women at risk of lymphedema)

Introduction: It is well-documented that lymphedema is one of the most feared long-term side effects of breast cancer (BC) treatment. However, to date, a standardized approach for the quantification and treatment of breast cancer-related lymphedema (BCRL) has yet to be established.

Aims: We propose a screening and intervention trial to assess the efficacy of early detection and intervention with various treatment strategies for BCRL. Intervention comprises the use of compression garments for mild lymphedema and compression garments +/- nighttime bandaging for moderate lymphedema. Other factors to be evaluated include: symptom clusters, treatment adherence, fear avoidance behavior, quality of life (QOL), upper extremity function, and risk factors for BCRL.

Eligibility Criteria: Women 18 years + with a confirmed BC diagnosis, no history of BC, no known metastatic or locally advanced disease, no history of primary lymphedema, sentinel lymph node biopsy or axillary lymph node dissection as part of definitive breast surgery.

Study Design: A two-stage study which includes a Screening and an Intervention trial. The screening trial will evaluate arm volume change during and after BC treatment with target accrual of 8000. Currently, 1286 participants have been enrolled among three sites including MGH, MD Anderson and Brigham and Women's Hospital. Patients will undergo perometer measurements and complete the MGH Lymphedema Evaluation Following Treatment for Breast Cancer (LEFT-BC) survey at each screening assessment to evaluate changes in functionality, upper extremity utilization, fear avoidance behaviors, and QOL. Screening visits will occur pre- and post-operatively, at the conclusion of chemotherapy and/or radiation therapy and every 3-8 months thereafter. Patients will become eligible for intervention trial enrollment if, during the course of screening, unilaterally affected patients develop a relative arm volume change (RVC) of ≥ 5% or bilaterally affected patients develop a weight adjusted change (WAC) of ≥ 5% which persists at a verification measurement within 4-8 weeks. Eligible subjects will be enrolled into one of two groups based on verification RVC/WAC: Group I – Mild Lymphedema (5-10% RVC/WAC) or Group II – Moderate Lymphedema (11-20% RVC/WAC). Subjects are then randomized within each group. Group I subjects are randomized to one of two arms: I-A – Observation, I-B – Compression, and Group II subjects are randomized to one of two arms: II-A – Compression, II-B – Compression + Night Compression Bandaging. Target accrual for the intervention trial is 336 subjects (Group I: 208, Group II: 128).

Clinical Relevance: The results of this study will yield Level I evidence on the effectiveness of early detection and intervention for BCRL. Findings may shape clinical practice in diagnosis and treatment, as well as provide insight regarding the risk factors, symptoms, upper extremity function, and QOL associated with BCRL.*Funding by award #s R01CA139118 &3P5OCA089393, AGT.

Citation Information: Cancer Res 2013;73(24 Suppl): Abstract nr OT2-5-01.

A novel, validated method to quantify breast cancer-related lymphedema (BCRL) following bilateral breast surgery

We sought to develop a formula to quantify breast cancer-related lymphedema (BCRL) after bilateral breast surgery, which functions independently of the contralateral arm and accounts for fluctuations in patient weight. Perometer arm measurements from 265 unilateral breast surgery patients were analyzed. We assessed the relationship between change in patient weight and contralateral arm volume and developed a weight-adjusted volume change formula (WAC). The WAC formula and previously-established RVC formula were compared for classification of BCRL (> or = 10% volume increase) in unilateral breast surgery patients. We then evaluated BCRL incidence using the WAC formula in 225 bilateral mastectomy patients. Change in patient weight and contralateral arm volume demonstrated an approximately linear relationship. Weight-adjusted arm volume change (WAC) was therefore calculated as WAC = (A2*W1)/(W2*A1) - 1 where A1 is pre-operative and A2 is post-operative arm volume, and W1, W2 are the patient's corresponding weights. In the unilateral analysis, there was no significant difference in number of patients classified as having BCRL using the RVC and WAC formulas (p = 0.65). In bilateral mastectomy patients 11.1% (25/225) developed BCRL, defined as > or = 10% WAC. Independent risk factors for lymphedema included axillary lymph node dissection (ALND) and higher pre-operative BMI (p<0.05). Use of this weight-adjusted arm volume change formula should be of value for quantification of BCRL after bilateral breast surgery.

Abstract P6-09-04: The Association of Low Level Arm Volume Increases with Lymphedema Symptoms Following Treatment for Breast Cancer

Purpose/Objective: The symptoms associated with breast cancer-related lymphedema are well-documented, and include sensations of heaviness, swelling, and tightness in the upper extremity and trunk. However, the clinical significance of low-level arm volume changes frequently experienced by breast cancer patients is not well understood. We sought to determine the association of low level arm volume changes with patient-reported lymphedema symptoms in women treated for breast cancer.

Methods: 267 patients who underwent surgical treatment for breast cancer from 2010–2012 were identified from a cohort of patients prospectively screened for lymphedema at our institution. Patients were assessed with perometer arm volume measurements and a survey of lymphedema symptoms pre and post operatively, and at 3–7 month intervals thereafter. Inclusion in this analysis was limited to unilaterally affected women with ≥ 3 assessments and ≥ 6 months of post-surgical follow-up. Arm volume changes were quantified as Relative Volume Change (RVC): RVC = (A2*U1)/(U2*A1) − 1, where A1 is pre-operative arm volume and A2 is post-operative arm volume on the affected side, and U1 and U2 are arm volumes on the unaffected side at these time points. Low level arm volume change was defined as a measurement with RVC ≥ 5% &lt;10% at an assessment ≥ 3 months post-operatively. Actuarial univariate and multivariate regression analysis was performed to determine the association of low level arm volume change with patient-reported lymphedema symptoms and clinicopathological characteristics.

Results: Low level arm volume changes occurred in 21.7% (58/267) of patients during the follow-up period at a median of 10.4 months post-operatively. Median post-operative follow-up was 12.4 months and 5 assessments per patient. By actuarial univariate analysis, symptoms of larger arm, shoulder, or neck (p &lt; 0.001), tighter sleeve, sleeve cuff, or ring (p &lt; 0.001), and having undergone axillary lymph node dissection (p = 0.02) or regional lymph node radiation (p = 0.01) were significantly associated with low-level arm volume change. By actuarial multivariate analysis, only symptoms of larger arm, shoulder, or neck (p &lt; 0.0001) were associated with low level arm volume change.

Conclusions: This data suggests that patients may be symptomatic for lymphedema even when experiencing low level arm volume changes. These patients should be followed closely for progression of measured arm volume or heightened lymphedema symptoms suggesting progression of the condition.

Citation Information: Cancer Res 2012;72(24 Suppl):Abstract nr P6-09-04.

Abstract OT3-2-02: The PREDICT Study (Prospective, Randomized Early Detection and Intervention after Breast Cancer-Treatment, for women at risk of lymphedema)

Introduction: It is well-documented that lymphedema is one of the most feared long-term side effects of breast cancer (BC) treatment. However, to date, a standardized approach for the quantification and treatment of breast cancer-related lymphedema (BCRL) has yet to be established.

Aims: We propose a screening and intervention trial that will assess the efficacy of early detection and intervention for BCRL. Intervention comprises the use of compression garments for mild lymphedema and compression garments +/− nighttime bandaging for moderate lymphedema. Other factors to be evaluated include: symptom clusters, treatment adherence, fear avoidance behavior, quality of life (QOL), upper extremity function, and risk factors for BCRL.

Eligibility Criteria: Women 18 years + with a confirmed BC diagnosis, no history of BC, no known metastatic or locally advanced disease, no history of primary lymphedema, sentinel lymph node biopsy or axillary lymph node dissection as part of definitive breast surgery.

Study Design: A two-stage study which includes a Screening and an Intervention trial. The screening arm will evaluate arm volume change during and after BC treatment with target accrual of 8000. Patients will undergo measurements via perometry and complete the MGH Lymphedema Evaluation Following Treatment for Breast Cancer (LEFT-BC) Survey at each screening appointment to evaluate changes in functionality, upper extremity utilization (fear associated avoidance), and QOL. Screening visits will occur pre- and post - operatively, at the conclusion of chemotherapy and radiation therapy and every 3–7 months thereafter. Patients will become eligible for enrollment into the intervention trial if, during the course of screening, they develop a relative arm volume change (RVC) of ≥ 5% which persists at a verification measurement within 4–8 weeks. Eligible subjects are enrolled into one of two groups based on verification RVC: Group I – Mild Lymphedema (5–10% RVC) or Group II – Moderate Lymphedema (11–20% RVC). Subjects are then randomized within each group. Group I subjects are randomized to one of two arms: I-A – Observation, I-B – Compression, and Group II subjects are randomized to one of two arms: II-A – Compression, II-B – Compression + Night Compression Bandaging. Target accrual for the intervention trial is 336 subjects (Group I: 208, Group II: 128).

Clinical Relevance: The results of this study will yield level I evidence on the effectiveness of early detection and intervention for BCRL. Findings may shape clinical practice in diagnosis and treatment, as well as provide insight regarding the risk factors, symptoms, upper extremity function, and quality of life (QOL) associated with BCRL.

*Funding by awards R01CA139118 & 3P5OCA089393, AGT

Citation Information: Cancer Res 2012;72(24 Suppl):Abstract nr OT3-2-02.

P4-14-01: Weight-Adjusted Change of Unilateral Arm Volumes for Quantification of Lymphedema after Bilateral Breast Surgery

Background: Accurate quantification of breast cancer-related lymphedema (BCRL) is important for early detection and successful management. Arm volume changes after unilateral breast surgery can be calculated through relative volume change (RVC) of the affected arm using the contralateral arm as a control (Ancukiewicz et al Int J Radiat Oncol Biol Phys 79(5):1436–43 2011). However there currently exists no accurate method for quantifying arm volume changes in patients after bilateral breast surgery. As the number of women undergoing bilateral mastectomies continues to increase, it is critical to develop a method to quantify arm volume changes in this population for detection of lymphedema. Our aim was to develop a weight-adjusted formula for unilateral arm volume changes independent of the contralateral arm for application in the setting of bilateral breast surgery.

Materials and Methods: We analyzed longitudinal measurements of arm volumes in 141 unilaterally affected patients undergoing screening for BCRL with a perometer at our institution (71 with left affected and 70 with right affected arms). Each patient had a baseline measurement prior to surgery and at least one post-surgical measurement. Median time of follow-up was 27.5 months and median standard deviation of longitudinal weight changes within patients during follow-up was 3%.

Results: Unilateral arm volume changes of the unaffected arm were correlated with weight changes at the last follow-up point (Kendall's tau=.58 and P&lt;.0001). Estimates of slope and intercept for median regression line between percent weight change and percent arm volume change evaluated for the unaffected arm at last follow-up are, respectively, .90 [95% CI] and .009 [95% CI]. Thus, percent weight change and percent arm volume change in the unaffected arm have an approximately linear relationship, such that the weight adjusted change (WAC) of affected unilateral arm volumes can be calculated according to the formula WAC=(A2*W1)/(W2*A1) — 1, where A1 is pre-surgical baseline arm volume on the affected side and A2 is post-surgical arm volume on the affected side, and W1, W2 are the patient's weights at these time points. Weight-adjusted change showed a strong correlation with RVC (RVC=(A2*U1)/(U2*A1) — 1), where A1, A2 are arm volumes on the side of the affected breast, and U1, U2 are volumes on the contralateral side at these time points (Kendall's tau=.41, P&lt;.0001).

Discussion: Unilateral arm volume changes can be quantified by adjusting for weight changes. We propose the weight-adjusted change (WAC) formula to calculate unilateral arm volume changes for detection and monitoring of BCRL in patients who undergo bilateral breast surgery. The validity of such a formula needs to be assessed in conjunction with clinically reported lymphedema.

Citation Information: Cancer Res 2011;71(24 Suppl):Abstract nr P4-14-01.

Recurrence rates and long-term survival in women diagnosed with breast cancer at age 40 and younger

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Background: Young age at diagnosis of breast cancer has been reported to be an independent risk factor for disease recurrence. However, there is little data on long term survival of young patients. We present long term follow up of a large cohort of women diagnosed with breast cancer at age 40 and younger. We determined rates of loco-regional recurrence (LRR), distant recurrence, and overall survival and adjusted for the patient and tumor characteristics which potentially predict outcomes.

Methods: Following Institutional Review Board approval, data from the medical records of 628 women diagnosed with breast cancer at age 40 or younger between 1996 and 2008 were collected. Survival curves were estimated using the Kaplan Meier method.

Results: Median age was 37 years (range: 21-40) and median follow-up was 72 months (range: 5-177). The rates of LRR as a first site of recurrence were 5.56% at 5 years and 12.11% at 10 years. In the entire population, with median follow-up of 72 months, there was no difference in the rates of loco-regional failure between patients who underwent breast conserving therapy (7.34%) compared to mastectomy (7.40%) (p=0.980). The rates of distant recurrence as a first event were 10.65% at 5 years and 14.58% at 10 years. Overall survival was 93.1% at 5 years and 87.26% at 10 years. 79.1% of patients received systemic therapy. For patients who developed disease recurrence, either LRR or distant, median time to first recurrence was 35 months (range: 3-167).

Conclusions: Women aged 40 and younger at diagnosis of breast cancer have a good prognosis, with low overall recurrence rates at 5 and 10 years. Local recurrence in our cohort is lower than in prior studies, suggesting advances in therapy have made breast conservation a safe option in young breast cancer patients.

Breast cancer after treatment of Hodgkin disease: Clinical outcome of 38 cases in 27 patients

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Background: Many studies showed that women who are cured of HD have an increased risk of developing BC. Our purpose is to evaluate detection, pathology, management and prognosis of BC occurring after HD. Methods: Thirty-eight cases of BC in 27 survivors of HD were analyzed. All patients received supradiaphragmatic RT and 13 had also chemotherapy for HD. Results: The median age of the patients at diagnosis of HD was 25.5 years. The median interval to develop BC was 15.9 years. The median age at diagnosis of BC was 45.8 years. Ten women (37%) had bilateral disease; one of them had DCIS, 7 years before developing bilateral disease. Cancers were detected by mammography (59.4%), symptom presentation (24.3%), clinical examination (8%), and incidental during elective mastectomy (8%). Using Fisher’s Exact test, DCIS was more frequent (27%), where nodal involvement (29.6%), and ER positivity (81.5%) were paralleled that reported in general population. Thirty tumors (79%) were managed by mastectomy due to prior RT. Two women received RT following mastectomy. Eight tumors treated by lumpectomy, followed by RT in two women; one received whole breast RT, while the other received fractionated partial breast irradiation using 3D-conformal technique (50Gy/25 fractions) and she is doing well 1 1/2 years after RT. Adjuvant systemic therapy, given to 17 patients, was well tolerated. The median follow-up after BC was 61 months. Using Kaplan-Maier procedure, the 6-year actuarial relapse-free survival for node-negative BC after HD was 100%. Node positive patients had a significantly lower RFS of 58.3% ± 19% (P = 0.01). Conclusions: Compared to patients with primary BC, patients developing BC after HD are more likely to be younger, have bilateral disease and have more frequent DCIS. Other pathological features and prognosis are similar to that reported in general population. Patient awareness, breast examination and mammography should be part of the follow-up program for HD survivors. Mastectomy remains the standard of care in most of cases; however, lumpectomy followed by fractionated partial breast irradiation might be a reasonable approach to investigate for women who refuse mastectomy.

No significant financial relationships to disclose.

Predictive value of histologic tumor necrosis after radiation

Postsurgical evaluation of histologic changes of tumors after preoperative chemotherapy and/or radiotherapy has been a routine clinical practice of pathologists and oncologists. There appears to be secure evidence that the extent of tumor necrosis vs. viable tumor cells postchemotherapy is a clinically useful predictor of outcome. The significance of histologic tumor necrosis after radiotherapy, however, has not been clearly established and deserves further investigation. We investigated the correlation between histological extent of tumor necrosis, survival of tumor transplants, and radiation doses in an experimental model using three human tumor xenografts. Three human tumor cell lines were investigated: STS-26, SCC-21, and HGL-21. Tumors were grown subcutaneously in athymic nude mice and received external beam radiation of different doses. Tumors were excised 2 weeks postirradiation. One-half of the tumor was divided into 1-mm(3) fragments and transplanted to naive mice. The other half was examined for histologic tumor necrosis. Transplant survival was strongly correlated with radiation dose, TCD(p) (radiation dose that results in local tumor control in proportion, p, to irradiated tumors). In contrast, there was no clear association between transplant survival rate and the extent of tumor necrosis. The experimental model demonstrated a strong inverse correlation between radiation doses and tumor transplant survival. Histologic tumor necrosis did not correlate well with radiation doses or transplant survival rates. Despite common practices in histologic examination of tumors posttherapy, clinical interpretations and implications of histologic tumor necrosis after radiotherapy should be considered with caution.

Risk of pneumonitis in breast cancer patients treated with radiation therapy and combination chemotherapy with paclitaxel

BACKGROUND

Some chemotherapy (CT) drugs, including taxanes, may enhance the effectiveness of radiation therapy (RT). However, combining these therapies may increase the incidence of radiation pneumonitis, a lung inflammation. In a retrospective cohort study, we evaluated the incidence of radiation pneumonitis in breast cancer patients treated with RT and standard adjuvant CT by use of doxorubicin (Adriamycin) and cyclophosphamide, with and without paclitaxel.

METHODS

Forty-one patients with breast cancer were treated with RT and adjuvant CT, including paclitaxel. Paclitaxel and RT (to breast-chest wall in all and lymph nodes in some) were delivered sequentially in 20 patients and concurrently in 21 patients. Paclitaxel was given weekly in some patients and every 3 weeks in other patients. The incidence of radiation pneumonitis was compared with that among patients in our database whose treatments did not include paclitaxel (n = 1286). The percentage of the lung volume irradiated was estimated. The Cox proportional hazards model was used to find covariates that may be associated with the observed outcomes. All P values were two-sided.

RESULTS

Radiation pneumonitis developed in six of the 41 patients. Three patients received paclitaxel concurrently with RT, and three received it sequentially (P =.95). The mean percentage of lung volume irradiated was 20% in patients who developed radiation pneumonitis and 22% in those who did not (P =.6). For patients treated with CT including paclitaxel, the crude rate of developing radiation pneumonitis was 14.6% (95% confidence interval [CI] = 5.6% to 29.2%). For patients treated with CT without paclitaxel, the crude rate of pneumonitis was 1.1% (95% CI = 0.2% to 2.3%). The difference between the crude rates with or without paclitaxel is highly statistically significant (P<.0001). The mean time to develop radiation pneumonitis in patients treated concurrently with RT and paclitaxel was statistically significantly shorter in patients receiving paclitaxel weekly than in those receiving it every 3 weeks (P =.002).

CONCLUSIONS

The use of paclitaxel and RT in the primary treatment of breast cancer should be undertaken with caution. Clinical trials with the use of combination CT, including paclitaxel plus RT, whether concurrent or sequential, must evaluate carefully the incidence of radiation pneumonitis.

The role of radiation therapy for primary breast cancer

Radiation therapy for breast cancer has gone through two revolutions in the last two decades: the routine use of radiation therapy in conjunction with breast-conserving surgery as an equivalent treatment to mastectomy, and the use of radiation therapy following mastectomy in advanced or node-positive disease. Indeed, the perception of postmastectomy radiation has gone full circle: from having no benefit when used for all cases, to being detrimental because of cardiac irradiation, to the present in which the selective use of irradiation in high-risk patients provides both an improvement in local control and an improvement of 8% to 10% in the survival rate. Improvements in radiation technique have reduced complications, in particular late cardiac deaths. The major issues still to be resolved are the targets for postmastectomy irradiation, determining which patients do not need radiation therapy for DCIS and for node-negative disease, and the efficacy of delivering radiation to just the affected quadrant rather than to the whole breast. At present, most patients approach radiation therapy for breast cancer with the knowledge that it has a very high probability of being successful.

13-cis-retinoic acid with alpha-2a-interferon enhances radiation cytotoxicity in head and neck squamous cell carcinoma in vitro

The treatment of locally advanced squamous cell carcinomas of the head and neck presents a challenge for oncologists. Radiation therapy alone fails to control many of these tumors. Chemotherapy added to radiation therapy has not clearly demonstrated an improvement in survival in the majority of trials reported to date. In this study, we have evaluated whether IFN-alpha-2a and/or 13-cis-retinoic acid (RA) enhance radiation cytotoxicity in a head and neck squamous cell carcinoma cell line (FaDu). Using a clonogenic cell survival assay, IFN-alpha-2a (1000 units/ml) or RA (1 microM) alone did not significantly enhance radiation cytotoxicity. The combination of the two agents, however, significantly increased the cytotoxicity of radiation against FaDu cells. The calculated survival fraction at 2 Gy was decreased from 0.649 with radiation alone to 0.477 when combined with the other two agents (P = 0.016), and the MID was decreased from 3.318 to 2.499 Gy (P = 0.028). A Phase I clinical trial to combine IFN-alpha-2a and/or RA in patients with unresectable head and neck cancer has been initiated.