Synchronous Bilateral Breast Cancer Patients Research Articles

Cardiac dose in the treatment of synchronous bilateral breast cancer patients between three different radiotherapy techniques (VMAT, IMRT, and 3D CRT)

PurposeSynchronous bilateral irradiation of both mammary glands and chest wall is a challenging task due to technical difficulties and limited evidence supporting an optimal technique to improve treatment outcomes. We studied and compared the dosimetry data of three radiotherapy techniques to select the most optimal one.MethodsWe compared three-dimensional conformal radiation treatment (3D CRT), intensity-modulated radiation therapy (IMRT), and volumetric modulated arc therapy (VMAT) during irradiation of synchronous bilateral breast cancer in nine patients followed by examination of dose distribution to the cardiac conduction system (SA node, AV node and Bundle of His), myocardium, lungs, left anterior descending artery (LADA) and right coronary artery (RCA) .ResultsVMAT is the most sparing technique for SBBC treatment. Even though doses to the SA node, AV node and Bundle of His were higher with VMAT (Dmean were 3.75 ± 0.62, 2.58 ± 0.83 and 3.03 ± 1.18 Gy respectively) compared with 3D CRT (Dmean were 2.61 ± 0.66, 1.52 ± 0.38 and 1.88 ± 0.70 Gy respectively), this difference is statistically insignificant. Doses to the right and left lung (average Dmean = 12.65 ± 3.20 Gy, V20Gy = 24.12 ± 6.25%), myocardium (Dmean = 5.33 ± 1.51 Gy, V10Gy = 9.80 ± 3.83%, V20Gy = 7.19 ± 3.15%, V25Gy = 6.20 ± 2.93%), and LADA (Dmean = 10.04 ± 4.92 Gy, V20Gy = 18.17 ± 13.24% and V25Gy = 15.41 ± 12.19%) were highest with 3D CRT. The highest Dmean in the cardiac conduction system (5.30 ± 2.23, 3.15 ± 1.61 and 3.89 ± 1.85 Gy respectively) was observed with IMRT, and a similar effect was noted in RCA (Dmean = 7.48 ± 2.11 Gy).ConclusionVMAT is the optimal and satisfactory radiation therapy technique for sparing organs at risk (OARs). With VMAT, a lower Dmean value was noted in the myocardium, LADA, and lungs. The use of 3D CRT significantly increases the dose of radiation reaching the lungs, myocardium, and LADA, which can subsequently cause cardiovascular and lung complications, but not in the cardiac conduction system.

Retrospective Analysis of Clinicopathological Features and Familial Cancer History of Synchronous Bilateral Breast Cancer.

Bilateral breast cancer is a strong predictor of BRCA 1/2 mutation and hence one criterion indicated for hereditary genetic testing. The purpose of this study is to assess the characteristics of synchronous bilateral breast cancer (SBBC) and its association with personal and familial cancer traits. Patients diagnosed with SBBC in our institute between 1992 and 2018 were retrospectively reviewed, and the information of clinicopathological features, personal and family cancer history were analyzed. Of the 307 SBBCs enrolled, the growing case number generally aligned with the regional breast cancer incidence after the era of population-based mammography screening. SBBC patients had similar cancer stages but worse survival outcomes than those in the standard scenario. A total of 42.0% had mixed pathological diagnoses, and 22.8% had discordant immunohistochemistry (IHC) subtypes from both sides, which contributed to treatment challenges. The correlation of SBBC with hereditary breast and ovarian cancer (HBOC) syndrome was strongly implied, as 20.7% of our SBBC patients with known familial cancer histories had HOBC-related familial cancers (breast, ovarian, or prostate cancers). These findings highlight the need for genetic counseling and germline mutation testing in patients with SBBC. Early PARP inhibitor treatment should also be considered in high-risk cases for outcome improvement.

Synchronous bilateral breast cancer treated with a 3-week hypofractionated radiotherapy schedule: clinical and dosimetric outcomes.

Background and purposeSynchronous bilateral breast cancer (SBBC) accounts for 1–3.5% of breast cancer patients. The aim of this study was to evaluate dosimetric issues, clinical outcomes, and acute toxicities for SBBC patients receiving synchronous bilateral hypofractionated radiotherapy (SBHRT) and to compare them with patients treated with synchronous bilateral normofractionated RT schedule (SBNRT).Materials and methodsFrom April 2016 to March 2020, 39 SBBC patients were referred to our institution. Patients were divided according to their prescription dose: Group A: 50 Gy/25fx (fractions), B: 60–64 Gy/25fx, C: 40.05 Gy/15fx; D: 48 Gy/15fx. Toxicity was evaluated using Common Terminology Criteria for Adverse Events (CTCAE)v.5.0.Results34 patients were finally evaluated. Median follow-up was 24 months for NF schedule and 9 months for HF schedule. In the HF schedule, no acute side-effects > G2 were observed and no dermatitis was reported in 6th month´s assessments. 95% of patients have no evidence of disease and only 1 patient presented local relapse in the first mammography after RT. No distant failures or deaths were observed. Regarding dosimetric issues, the inter-patient average Dmean for the heart was: Group A: 5.0 Gy (4.6–5.5), Group B: 4.4 Gy (4.1–5.4), Group C: 4.8 Gy (4.5–5.1) and Group D: 5.3 Gy (4.4–5.6). For the lungs, the inter-patient average Dmean was: Group A: 10.8 Gy (9.8–12.2), Group B: 11.5 Gy (11.3–12), Group C: 9.8 Gy (9.3–10.5) and Group D: 10.5 Gy (10–11.3).ConclusionsThis is the first study reporting the safety, feasibility, and tolerability of 40.05 Gy/15fx over 3 weeks for the treatment of SBBC patients. Further study with larger accrual is mandatory.

Association of molecular subtype concordance and survival outcome in synchronous and metachronous bilateral breast cancer

BackgroundThe aim of this study was to analyze the association of molecular subtype concordance and disease outcome in patients with synchronous bilateral breast cancer (SBBC) and metachronous breast cancer (MBBC). Patients and methodsPatients diagnosed with SBBC or MBBC in the Surveillance, Epidemiology, and End Results (SEER) database or Comprehensive Breast Health Center (CBHC) Ruijin Hospital, Shanghai were retrospectively reviewed and included. Clinicopathologic features, molecular subtype status concordance, and prognosis were compared in patients with SBBC and MBBC. Other prognostic factors for breast cancer-specific survival (BCSS) and overall survival (OS) were also identified for bilateral breast cancer patients. ResultsTotally, 3395 and 115 patients were included from the SEER and Ruijin CBHC cohorts. Molecular subtype concordance rate was higher in the SBBC group compared to MBBC in both SEER cohort (75.8% vs 57.7%, p < 0.001) and Ruijin CBHC cohort (76.2% vs 45.2%, p = 0.002). Survival analyses indicated that SBBC was related to worse BCSS than MBBC (p = 0.015). Molecular subtype discordance was related to worse BCSS (hazard ratio (HR), 1.64, 95% confidential interval (CI), 1.18–2.27, p = 0.003) and OS (HR, 1.59, 95% CI, 1.24–2.04, p < 0.001) in the SBBC group, but not for the MBBC group (p = 0.650 for BCSS, p = 0.669 for OS). ConclusionsMolecular subtype concordance rate was higher in the SBBC group than MBBC group. Patients with discordant molecular subtype was associated with worse disease outcome in the SBBC patients, but not in MBBC, which deserves further clinical evaluation.

Optimizing Adjuvant Radiation Planning Outcomes in Patients with Synchronous Bilateral Breast Cancer

Background: Breast cancer is the most common cancer diagnosed worldwide, synchronous bilateral breast cancer accounts for unique entity of the disease, particularly post-operative radiotherapy for Synchronous Bilateral Breast Cancer (SBBC) is challenging with lack of evidence about the best irradiation technique. In this study, we tried to explore the optimum radiotherapy technique regarding the dosimetric parameters. Methods: We recruited 15 SBBC patients in whom post-operative radiotherapy was indicated and we established three plans for each patient using 3DCRT, IMRT and VMAT, and then we compared the three plans as regard target volume coverage parameters and organs at risk (OAR) doses. Results: We found that PTV coverage parameter was superior with IMRT compared with 3DCRT and VMAT in terms of Dmean (p = 0.001), D95% (p = 0.001), Dmax (p = 0.0001), conformity index (p = 0.0001) and HI (p = 0.0001). Doses to OAR were not significantly different between the three techniques in cardiac dose and LAD maximum dose, but 3DCRT was superior in LAD mean dose (p = 0.03) and lung volume receiving 20 Gy (V20) and 10 Gy (V10) (p = 0.0001), but this difference was non-significant between 3DCRT and IMRT (p = 0.4 and 0.06 respectively), while VMAT led to the highest doses to LAD and lung. Conclusions: IMRT showed the best target coverage parameters in post-operative radiotherapy for SBBC compared with 3DCRT and VMAT. For OAR doses IMRT showed comparable results with 3DCRT, while VMAT delivered a significantly higher dose to OAR.

Heart and Lung Dose Metrics in Radiation Therapy Patients Treated for Synchronous Bilateral Breast Cancer (SBBC): A Decade in Review (2011-2018)

Heart and Lung Dose Metrics in Radiation Therapy Patients Treated for Synchronous Bilateral Breast Cancer (SBBC): A Decade in Review (2011-2018) Synchronous bilateral breast cancer (SBBC) is a relatively rare clinical presentation of which there is very little data, in the literature, describing organs at risk (OAR) dose limits for heart and lungs caused from radiation treatment (RT). Given that these patients typically have large irradiated treatment volumes relative to their unilateral counterparts, a retrospective review of heart and lung dose metrics was undertaken. The primary aim was to assess median mean heart dose (MHD), median mean lung dose (MLD) and the median volume of lung receiving 20Gy (V20) and 5Gy (V5). Secondary aims included analyses of 3D-CRT technique-based factors such as free-breath (FB), breath-hold (BH) and treatment field volumes associated with higher medium MHD and medium MLD. 92 patients who underwent bilateral RT from 2011-2018 were included. All patients received 3D-CRT conventional (50Gy in 25 fractions) or hypofractionation (42.56Gy in 16 fractions). Treatment volumes were as follows: whole-breast/chest wall RT (2 field tangential beams) +/- local-regional RT (3-4 field beams, including supraclavicular nodes +/- axillary nodes). When treatment included the internal mammary chain (IMC) this was considered wide-tangent RT. Boost data was not collected in this report. Median MHD (Gy) and median MLD (Gy) were stratified by conventional and hypofractionation. Factors investigated for correlation with higher median MHD/MLD were treatment volume, fractionation, heart/lung volumes, baseline-separation, heart shielding, FB and BH techniques. Overall medium lung V20 & V5 were collected. Backward stepwise selection was conducted in the multivariable analysis. The overall median MHD/MLD for conventional RT n = 52 and hypofractionated RT n = 40 was 2.96Gy and 2.03Gy for heart respectively and 10.53Gy and 6.35Gy for lung respectively. The median MHD/MLD multivariable analysis found locoregional RT n = 49 and the use of wide-tangent RT n = 20 to be associated with significantly higher MHD (P<0001) and MLD (P<0001). No other factors such as lung/ heart volumes, heart shielding n = 45 and the use of FB n = 79 versus BH n = 11 were identified as significantly associated with MHD and MLD. The median V20 and V5 lung volumes for conventional RT was 20% & 39% respectively and for hypofractionated RT 12% and 23% respectively. SBBC patients in our study showed overall acceptable MHD/MLD as well as V20 & V5 lung metrics when compared to those patients seen in the literature with unilateral breast RT. Furthermore, differences in median MHD/MLH in FB versus BH did not approach statistical significance. This suggests that careful treatment consideration in terms of BH technique and/or use of heart/lung shielding strategies are being appropriately made to minimize OAR dose limits to this patient demographic.

Hybrid Volumetric Modulated Arc Therapy With Deep Inspiration Breath Hold for Hypofractionated Bilateral Breast Irradiation: Coming Together is a Beginning

Purpose of the present study was to explore the benefits of hybrid volumetric modulated arc therapy (H-VMAT) & deep inspiratory breath hold (DIBH) for synchronous bilateral breast cancer patients. Six patients diagnosed with bilateral breast cancer were planned for H–VMAT and dual Isocenter VMAT. On the planning CT data set planning target volume (PTV) & organs at risk (OARs) like lungs, heart, liver, celiac plexus with gastro-esophageal junction (GEJCP), left anterior descending artery (LAD), right coronary artery (RCA) were delineated using standard delineation guidelines. Dose prescribed was 40.5 Gy in 15 fractions to bilateral breast. PTV & OARs dosimetric parameters were compared using non-parametric Mann Whitney test. The monitor units (MU) and beam-on time were used as an objective measure to evaluate delivery efficiency. Coverage, conformity index, and homogeneity index in both techniques were comparable. However, H-VMAT achieved better sparing of heart & lung at low dose regions (V5Gy to heart was 23.4+10.1 & 39.5+16.3; p<0.01), V5Gy to lungs was 41.3+8.7 & 59.9+6.9; p<0.01). In addition, V20Gy to lungs and Dmean to GEJCP were better with H-VMAT (9.4+3.7 & 14.3+3.9; 1.9+1.4 & 2.9+2.1, respectively). There were no significant differences in relatively high and intermediate dose regions in both techniques for OARs (LAD, RCA, heart, liver). MU was comparable, while beam-on time was higher in H-VMAT. Overall, H-VMAT reduces low dose bath and is comparable in terms of high and intermediate dose to OARs. These dosimetric benefits have the potential to reduce not just late radiation toxicity but acute toxicities like radiation induced nausea and vomiting (RINV) and pneumonitis in the setting of hypofractionation.

An efficient treatment planning approach to reduce the critical organ dose in volumetric modulated arc therapy for synchronous bilateral breast cancer patients

Treatment planning for patients with synchronous bilateral breast cancer (SBBC) is challenging due to the technical complexity of bilateral treatment. To minimize both high-dose and low-dose volumes of the heart and lungs being irradiated, we proposed an efficient and simple strategy for volumetric modulated arc therapy (VMAT) treatment planning in this study. Five SBBC patients were enrolled in this study. We utilized two pseudo block planning structures to minimize the high-dose volume of the whole lungs and heart and confine the low-dose areas in normal organs for VMAT planning. The prescription delivered was 45 Gy in 25 fractions to the whole breast. The VMAT treatment plan consisted of two partial arcs. In terms of the whole lungs, the average V5Gy, V10Gy and V20Gy in the VMAT-B plan (with two pseudo planning block structures) for the five patients were 34.8 ± 7.2%, 23.4 ± 5.0% and 14.8 ± 3.0%, respectively. For the VMAT-NB plan (without two pseudo planning block structures), the average V5Gy, V10Gy and V20Gy were 38.6 ± 6.8%, 27 ± 5.9% and 18.4 ± 4.0%, respectively. For the heart, the average V5Gy, V10Gy, V20Gy and V30Gy in the VMAT-B plan were 19.6 ± 3.1%, 7.0 ± 2.5%, 2.2 ± 1.2% and 0.7 ± 0.7%, respectively, while the mean values in the VMAT-NB plan were 26.2 ± 6.3%, 11.3 ± 3.9%, 3.9 ± 1.8% and 1.5 ± 1.1%, respectively. We designed an approach to reduce both the high-dose and low-dose volumes by utilizing pseudo planning structures in the VMAT treatment plan. The dosimetric results of this study showed that the pseudo block structures have the potential to reduce the risks of radiation pneumonitis and heart disease, while preserving the same tumor control rate.

Concordance of Hormone Receptor Status and BRCA1/2 Mutation Among Women With Synchronous Bilateral Breast Cancer.

Goals: BRCA1/2 mutations are associated with bilateral breast cancer. The extent of concordance between synchronous bilateral breast cancer (SBBC) tumors with respect to hormone receptor expression and BRCA1/2 mutations is unknown. We investigated the distribution of BRCA1/2 mutations and bilateral estrogen receptor (ER) status in SBBC.Methods: A retrospective analysis was performed on 15,337 patients with primary breast cancer who underwent surgical treatment at the Fudan University Shanghai Cancer Center between 2007 and 2014. We included 163 patients with synchronous bilateral breast cancer who had germline BRCA1/2 mutations testing. BRCA1/2 pathogenic/likely pathogenic mutations and other clinicopathological characteristics were studied in further analyses.Results: Patients with SBBC developed breast cancer at an older age and had a higher rate of ER positivity than patients with UBC (p < 0.001, separately). In contrast, 14.1% of SBBC patients had carcinomas with a lobular component in either breast based on pathological reports (p < 0.001). Twelve patients had BRCA1 mutations, and 14 patients had BRCA2 mutations, while no patients had mutations in both genes. The BRCA1/2 mutation rate was higher in younger patients (23.4 vs. 11.1%, p = 0.036). SBBC patients with a family history of breast cancer or bilateral ER-negative disease had a higher frequency of BRCA1/2 mutations than the cohort without a history of these conditions. SBBC with a bilateral ER-discordant status had a very low frequency of BRCA1/2 mutations (5.6%). Patients with an ER-positive (concordant or discordant) status had better 3-year disease-free survival than patients with a concordant ER-negative status (HR = 0.324, 95% CI: 0.126–0.837, P = 0.020). However, the outcomes were similar during long-term follow-up. Pathological lymph node stage was the only prognostic factor for SBBC in both univariate and multivariate Cox analyses.Conclusions: Our study shows that Chinese women with SBBC have different characteristics from their UBC counterparts. SBBC patients with a younger age, family history of breast cancer, or bilateral ER-negative disease are more likely to have BRCA1/2 mutations. SBBC patients with a concordant ER-negative status had worse early outcomes. Our results suggest that there may be additional factors underlying the tumor biology and genetics of SBBC.

Heart and Cardiac Substructure Dose Sparing in Synchronous Bilateral Breast Radiotherapy: A Dosimetric Study of Proton and Photon Radiation Therapy.

Background: Synchronous bilateral breast cancer (SBBC) is rare. The purpose of this study was to compare the dosimetric differences in intensity-modulated radiation therapy (IMRT), volumetric-modulated arc therapy (VMAT), helical tomotherapy (HT), and intensity-modulated proton therapy (IMPT) to find an optimal radiotherapy technique for bilateral breast cancer radiotherapy.Methods: For 11 patients who received synchronous bilateral whole-breast irradiation without local lymph nodal regions, six plans were designed for each patient: IMRT with a single isocenter (IMRT-ISO1), IMRT with two isocenters (IMRT-ISO2), VMAT with a single isocenter (VMAT-ISO1), VMAT with two isocenters (VMAT-ISO2), HT, and IMPT. The differences between the single- and dual-isocentric plans for IMRT and VMAT were compared, and the plan with the better quality was selected for further dosimetric comparisons with IMPT and HT. The plan aimed for a target coverage of at least 95% with the prescription dose of 50 Gy [relative biological effectiveness (RBE)] while minimizing the dose of organs at risk (OARs).Results: IMRT-ISO1 and VMAT-ISO2 plans were adopted for further dosimetric comparisons because of the reduced dose of the heart and/or lungs compared to IMRT-ISO2 and VMAT-ISO1 plans. The dose coverage of the planning target volume (PTV) was significantly higher in IMPT plans than that in all other plans. VMAT and IMPT plans showed the best conformity, whereas IMRT plans showed the worst conformity. Compared to IMRT and VMAT plans, IMPT and HT plans achieved significantly higher dose homogeneity. IMPT plans reduced the mean dose and low dose volume (V5, V10, and V20) of the heart, left anterior descending artery (LAD), and left ventricle (LV). In high-dose volumes of the heart and cardiac substructures, the IMPT, VMAT, and HT techniques showed similar advantages, and IMRT plans increased the values more than other techniques. IMPT plans had the maximal lung and normal tissue sparing but increased the skin dose compared to IMRT and VMAT plans.Conclusions: IMPT plans improve both the target coverage and the OARs sparing, especially for the heart, cardiac substructures (LAD and LV), lungs and normal tissue, in synchronous bilateral breast radiotherapy. VMAT and HT could be selected as suboptimal techniques for SBBC patients.

Synchronous bilateral breast cancer patients treated with hypofractionated bilateral breast irradiation: A dosimetric and clinical study.

Bilateral breast irradiation is technically challenging and there is limited information regarding optimal technique and outcomes. Hypofractionated Radiotherapy (HFRT) has emerged as the new standard of care in early breast cancer. However, there are concerns in using hypofractionation for bilateral breast irradiation due to larger volumes and potential toxicity. Our aim was to analyze the dosimetric data and clinical outcomes in these patients. Patients with synchronous bilateral breast cancer (SBBC) treated with bilateral breast irradiation were analyzed. All patients received simultaneous bilateral breast with or without regional nodal irradiation using a hypofractionated schedule of 40 Gy in 15 fractions over 3 weeks with single isocenter bi-tangential field-in-field intensity-modulated radiation therapy (FIF-IMRT) technique. Seven patients of SBBC were treated at our institute from 2015 to 2017. All patients were postmenopausal females. Five patients underwent bilateral modified radical mastectomy; two patients underwent bilateral breast conservative surgery. All patients received systemic anthracycline-based chemotherapy. The mean cardiac dose was 3.73 ± Gy and V 25 was 3.26% ± 1.96%. V 20 of lung ranged from 23.48% ± 4.47% and the mean esophageal dose was 3.6 ± 2.00 Gy. No patient had acute toxicity higher than Grade 2. At a median follow-up of 48 months, one patient died due to systemic progression. No patient reported any late toxicity. Bilateral breast irradiation using a hypofractionated schedule with single isocenter FIF-IMRT technique is technically feasible with minimal acute toxicity and no significant late effects on early follow-up.

Breast cancer mortality in synchronous bilateral breast cancer patients

BackgroundEvidence suggests that patients with synchronous bilateral breast cancer (SBBC), diagnosed within 4 months, have an inferior prognosis compared to unilateral breast cancer (UBC) patients. Using data from nationwide Danish clinical databases, this cohort study investigated whether the inferior prognosis could be explained by SBBC patients having a more aggressive disease, or whether the prognosis could be explained by the fact that they have two simultaneous cancers.MethodsPatients were diagnosed from 1999–2015. The main outcome was excess mortality, subtracting background population mortality from observed mortality. Differences between SBBC and UBC patients were evaluated by rate ratios (RR) and estimated by Poisson regression.ResultsIn total, 1214 SBBC and 59 177 UBC patients were included. SBBC patients had a significantly higher excess mortality than UBC patients after adjustment for age and period (RR = 1.73; 95% CI:1.44–2.08; p < 0.01) and after adjusting for characteristics of the worst tumour as traditionally done (RR = 1.31; 95% CI:1.08–1.57; p = 0.01). However, adjusting for characteristics of both tumours, using a more advanced competing risks model, no difference was observed (RR = 1.01; 95% CI:0.83–1.22; p = 0.93).ConclusionsOur study does not support that the inferior prognosis in SBBC patients is due to having more aggressive tumours per se, but rather the combined effect of having two simultaneous cancers.

Synchronous bilateral breast cancer patients submitted to conservative treatment and brachytherapy - The experience of a service.

The incidence of breast carcinoma (BC) has increased in the last years. Between 2 and 12% of patients diagnosed with BC will develop bilateral breast carcinoma (BBC). The treatment of these carcinomas is more aggressive than unilateral BC. To perform a retrospective qualitative analysis of BBC patients whose treatment has included brachytherapy (BT) and to present a revised literature on this issue. The cases of BBC whose treatment included brachytherapy were revised. The literature on this issue was refreshed. Five women, aged between 54 and 78 at the time of the diagnosis, submitted to conservative surgery followed by external radiotherapy (RT) with boost of BT or exclusive BT (APBI), in the IPO-P BT Service between 2003 and 2016. The patients with BBC have slightly higher rates of local recurrences, mostly in the tumor bed, where there is a higher risk of local recurrence. Patients treated with BT had lower rates of recurrences than those treated with photons and electrons. BBC represents a complex challenge for doctors, because in some cases there is a tendency to use more aggressive treatments and, at the same time, it is not easy to achieve the timing for the correct treatment.

536 (PB-169) - Histopathologic characteristics in synchronous bilateral breast cancer patients: A nationwide Danish cohort study from 1999–2015

536 (PB-169) - Histopathologic characteristics in synchronous bilateral breast cancer patients: A nationwide Danish cohort study from 1999–2015

Breast‐conserving therapy: An alternative to optimal cosmetic outcome and comparable prognosis in synchronous bilateral breast cancer

AimOur main purpose initially was to simple retrospectively analyze the current literature for publishing and comparative studies on synchronous bilateral breast cancer (SBBC) with unilateral breast cancer (UBC) or metachronous bilateral breast cancer (MBBC) post breast‐conserving therapy BCT, and furthermore gather data on impact of bilateralism in changes of overall survival (OS), disease‐free survival (DFS) and local recurrence rate (LCC) to reach a sensible conclusion.Patients and MethodsWe conducted a Medline database search for all studies reporting on SBBC patients who underwent BCT and comparison of this entity with UBC OR MBBC. Assessment of bilateralism as a prognostic factor and estimation of its impact on DFS, LCC and OS of SBBC patients still generates many contradictions in the literature. Comparison between relatively small entities of SBBC with UBC using retrospective studies or population‐based inquiries are the primary line of research.ResultsA worst prognostic effect or a downward tendency towards increased mortality rates for simultaneous occurrence of breast carcinomas compared to UBC patients is commonly supported by many studies. Clinical experiences of many physicians and data achieved from the majority of studies have suggested that application of breast‐conversing therapy for SBBC patients, even though appears to be a challenging alternative to mastectomy and has yielded better cosmetic outcome and similar DFS and OS.ConclusionAlthough the majority of studies report a more adverse survival outcome for SBBC patients, breast‐conserving therapy is a feasible surgical choice for this group of patients, as it is a suitable alternative to mastectomy.

WCC 2017-A-106: Analysis of Heart and Lung Doses in Synchronous Bilateral Breast Cancer Patients Treated with Bilateral Breast Irradiation

WCC 2017-A-106: Analysis of Heart and Lung Doses in Synchronous Bilateral Breast Cancer Patients Treated with Bilateral Breast Irradiation

Synchronous bilateral breast cancer irradiation: clinical and dosimetrical issues using volumetric modulated arc therapy and simultaneous integrated boost.

The aim of the present retrospective analysis was to evaluate dosimetric parameters, feasibility and outcome for Synchronous Bilateral Breast Cancer (SBBC) patients treated with adjuvant radiotherapy (RT) by Volumetric Modulated Arc Therapy (VMAT). From September 2011 to April 2016, 1100 Breast Cancer (BC) patients were referred to our institution to receive adjuvant breast RT, and those with SBBC were selected for the present analysis. A total of 16 patients were identified. A total dose of 50Gy in 25 fractions was prescribed to the Planning Target Volume of the whole bilateral breast (PTVBN) with or without the supraclavicular and infraclavicular nodes, while a total dose of 60Gy in 25 fractions was prescribed to the surgical bed (PTVboost). Several V xGy and Dx% parameters were analyzed for the PTVs, together with Conformity and Homogeneity indexes (CI, HI), and for the critical Organs at risk (OARs), lungs and heart first. With a median follow-up of 24months, no acute or late side effects more than grade 2 were observed. All patients are alive without any sign of disease. For target dose coverage, our observed inter-patients averages (±1 sd) were V 95% Dp=96.7±1.6% (96.3±1.8%) to the left (right) PTVBN, V 95% Dp=98.6±2.7% (99.4±0.9%) to the left (right) PTVboost, and D 2%=64.4±1.8Gy (65.0±2.0Gy) to the left (right) PTVboost, respectively. With regard to the heart, the inter-patient average of D mean was 8.3±3.3Gy. For the lungs, the inter-patient average of D mean, V 5Gy and V 20Gy were 11.8±2.3Gy, 78.9±15.3% and 15.7±5%, respectively. The present retrospective analysis showed the feasibility, tolerability and safety of VMAT in the treatment of SBBC patients. Further studies are necessary to confirm these preliminary data.

Prognosis of synchronous bilateral breast cancer: a review and meta-analysis of observational studies.

Currently, no consistent evidence-based guidelines for the management of synchronous bilateral breast cancer (SBBC) exist and it is uncertain how presenting with SBBC affects patients' prognosis. We conducted a review of studies analyzing the association between SBBC and prognosis. The studies that reported adjusted effect measures were included in meta-analyses of effect of bilaterality on breast cancer mortality. From 57 initially identified records 17 studies from 11 different countries including 8,050 SBBC patients were included. The quality of the studies varied but was generally low with small sample sizes, and lack of consistent, detailed histo-pathological information. When doing meta-analysis on the subgroup of studies that provided adjusted effect estimates on breast cancer mortality (nine studies including 3,631 SBBC cases), we found that bilaterality in itself had a negative impact on prognosis after adjustment for known prognostic factors (pooled HR 1.37, 95% CI 1.24-1.50, p<0.0001). Multiple sensitivity analyses indicated robustness of the overall estimate. This review summarizes the current evidence of the association between SBBC and prognosis. The previously accepted convention that appropriate adjuvant treatment can be determined by considering the higher risk cancer was not confirmed in this review; rather it seems that being diagnosed with two tumors simultaneously entails a worse prognosis above and beyond that of the unilateral cancers of the same stage. To determine the true association between SBBC and breast cancer prognosis, studies of large and updated samples of SBBC should be done and include thorough histo-pathologic information.

Abstract P5-13-09: Evaluation on the risk factors and prognosis for patients with synchronous bilateral breast cancer in a Chinese cohort

Abstract Background: There has been an increasing rate of synchronous bilateral breast cancers, mainly because of the increased morbidity, improved detection abilities, better prognosis and higher life expectancy of breast cancer patients. However, evidences in the literature regarding the risk factors of bilateral breast cancers are scare, and the survival of synchronous bilateral breast cancers still remain controversies. The purpose of the present study is to investigate the risk factors and prognosis of bilateral breast cancers in a Chinese cohort. Methods: The present study included 181 patients with synchronous bilateral breast cancer and 10,831 patients with unilateral breast cancer treated in Fudan University Shanghai Cancer Center between Jan 2007 and Dec 2012. Patients with metastases or inflammatory diseases, or metachronous bilateral breast cancer (after 6 months of first cancer) were excluded. Age of the cases, family history, menopausal status, histology types, pathological stages, types of accompanied benign lesions, and patterns of surgeries and adjuvant therapies were examined to investigate the risk factors of bilateral breast cancers. Results: Patients with synchronous bilateral breast cancer were significantly elder than those with unilateral breast cancer (mean age 53 yrs vs. 51yrs, p&amp;lt;0.001). Presence of sclerosing adenoma and lobular carcinoma component were the two independent risk factors of early-stage synchronous bilateral breast cancer, with the relative risk rate at 5.52 (95% CI: 3.04-10.01) and 5.00 (95% CI: 2.64-9,47), respectively. The rate of in situ carcinoma with or without microinvasion was significantly higher in patients with sclerosing adenoma associated synchronous bilateral breast cancers at 64.3%. With a median follow-up of 35 months, the disease free survival for synchronous bilateral breast cancer was 95.0%, similar to that of unilateral breast cancer. However, for synchronous bilateral breast cancer patients with N3 disease or previously received neoadjuvant therapy (20 cases), the 1.5 year-disease free survival was merely 50%, significantly worse than that of unilateral breast cancer with N3 disease or previous neoadjuvant therapy. Conclusion: The rate of synchronous bilateral breast cancer was higher in patients with sclerosing adenosis or lobular carcinoma component. The prognosis for early-stage synchronous bilateral breast cancer was similar to those with early-stage unilateral breast cancer. However, among patients with N3 disease or previously received neoadjuvant therapy, synchronous bilateral cohort was associated to worse survival compared with unilateral cohort. Citation Information: Cancer Res 2013;73(24 Suppl): Abstract nr P5-13-09.

Impact of Presurgical Breast Magnetic Resonance Imaging (MRI) on Surgical Planning - A Retrospective Analysis from a Private Radiology Group

Presurgical bilateral breast MRI is being increasingly utilized in newly diagnosed breast cancer patients to identify the presence of other potentially malignant lesions and thereby guide surgical planning. The authors have performed a retrospective analysis of presurgical MRIs in 445 breast cancer patients, consecutively seen in a community practice setting, to determine what risk factors may be associated with bilateral synchronous breast cancer. Clinical, imaging, surgical, and pathological data were collected on these newly diagnosed patients, who underwent presurgical breast MRIs from November 1, 2008 through October 31, 2009. The MRIs detected 84 incremental (additional) malignancies in 66 (14.8%) patients, including 22 patients in the contralateral breast (4.9%) and 48 patients who had ipsilateral incremental malignancies (10.8%). The presurgical breast MRIs had a sensitivity of 99% and a specificity of 86%. Based on the imaging study and the subsequent biopsy(s), 105 patients (23.6%) had changes in their surgical planning. For those with incremental breast malignancies, the synchronous bilateral breast cancer patients were older (67.5±13.5years, p=0.01). Patients with ipsilateral incremental malignancies were younger (55.6±10.4years of age, p=0.03). A strong family history and ductal carcinoma in situ (DCIS) as the index lesion also appeared to be associated with increased bilateral malignancy detection. The authors conclude that although presurgical MRI remains controversial, our data support its role in surgical planning for newly diagnosed breast cancer patients.