Postmastectomy intensity modulated radiation therapy following immediate expander-implant reconstruction

The impact of metal implants on the dose and clinical outcome of radiotherapy (Review)

Radiotherapy (RT) is one of the most widely used and effective cancer treatments. With the increasing need for organ reconstruction and advancements in material technology, an increasing number of patients with cancer have metallic implants. These implants can affect RT dosage and clinical outcomes, warranting careful consideration by oncologists. The present review discussed the mechanisms by which different types of metallic implants impact various stages of the RT process, examined methods to mitigate these effects during treatment, and discussed the clinical implications of metallic implants on RT outcomes. In summary, when metallic implants are present within the RT field, oncologists should carefully assess their impact on the treatment.

Postmastectomy radiotherapy in breast reconstruction: Current controversies and trends

Breast cancer is the most common cancer among women worldwide. Postmastectomy radiotherapy (PMRT) is an essential component of combined therapy for early-stage, high-risk breast cancer. Breast reconstruction (BR) is often considered for patients with breast cancer who have undergone mastectomy. There has been a considerable amount of discussion about the optimal approach to combining PMRT with BR in the treatment of breast cancer. PMRT may increase the risk of complications and prevent good aesthetic results after BR, while BR may increase the complexity of PMRT and the radiation dose to surrounding normal tissues. The purpose of this review is to give a broad overview and summary of the current controversies and trends in PMRT and BR in the context of the most recent literature available.

Oncoplastic breast consortium recommendations for mastectomy and whole breast reconstruction in the setting of post-mastectomy radiation therapy

Aim

Demand for nipple- and skin- sparing mastectomy (NSM/SSM) with immediate breast reconstruction (BR) has increased at the same time as indications for post-mastectomy radiation therapy (PMRT) have broadened. The aim of the Oncoplastic Breast Consortium initiative was to address relevant questions arising with this clinically challenging scenario.

Methods

A large global panel of oncologic, oncoplastic and reconstructive breast surgeons, patient advocates and radiation oncologists developed recommendations for clinical practice in an iterative process based on the principles of Delphi methodology.

Results

The panel agreed that surgical technique for NSM/SSM should not be formally modified when PMRT is planned with preference for autologous over implant-based BR due to lower risk of long-term complications and support for immediate and delayed-immediate reconstructive approaches. Nevertheless, it was strongly believed that PMRT is not an absolute contraindication for implant-based or other types of BR, but no specific recommendations regarding implant positioning, use of mesh or timing were made due to absence of high-quality evidence. The panel endorsed use of patient-reported outcomes in clinical practice. It was acknowledged that the shape and size of reconstructed breasts can hinder radiotherapy planning and attention to details of PMRT techniques is important in determining aesthetic outcomes after immediate BR.

Conclusions

The panel endorsed the need for prospective, ideally randomised phase III studies and for surgical and radiation oncology teams to work together for determination of optimal sequencing and techniques for PMRT for each patient in the context of BR

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Autologous breast reconstruction is increasingly preferred over implants in the setting of radiation therapy.

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Use of patient-reported outcomes is endorsed.

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Shape and size of reconstructed breasts can hinder radiotherapy planning.

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There is a need for randomised phase III trials.

Post-mastectomy radiation therapy with helical tomotherapy in patients with or without immediate implant-based reconstruction: a single institution experience

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We report very low doses to the heart and lung for PMRT with Helical Tomotherapy.

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Breast implant improves dosimetric results with reduced heart and lung doses.

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No local recurrence was seen in the posterior part of implants.

Introduction

We report on our experience of using Helical Tomotherapy (HT) in the context of post-mastectomy radiation therapy (PMRT) with or without immediate implant-based breast Reconstruction (IBR).

Material and methods

The study included a total of 173 patients who underwent PMRT with HT between 2013 and 2015 in our institution (87 immediate breast reconstructions with retropectoral implants (IBR + ), 86 without reconstructions (IBR-)). The chest wall target volume included subcutaneous tissue and pectoralis muscle and excluded the posterior region of the implant as well as the ribs.

Results

Median time to initiation of the first adjuvant treatment from mastectomy was similar between the two groups (p = 0.134). Dose coverage to the chest wall was significantly improved for the IBR + group (V95% = 95.1 % versus 92.0 %; p < 0.0001). The irradiated volume of the ipsilateral lung was significantly decreased in the IBR + group with a median V20Gy of 11.6 %, compared to 15.2 % for the control group (p < 0.0001). The median heart V15Gy was also significantly lower in the IBR + group than in the control group (1.7 vs 2.5 %; p = 0.0280). The reconstruction failure rate was 14.9% (n = 13). After a median follow-up of 65 months, loco regional recurrence rate was low in both groups: 3 patients (3.4%) in the IBR + group and 5 patients (5.8%) in the control group, without any local recurrence in the posterior part of the implant.

Conclusions

The presence of a breast implant reduces cardiac and pulmonary doses during Tomotherapy irradiation, without compromising oncological outcomes.

Breast Radiotherapy after Oncoplastic Surgery-A Multidisciplinary Approach

Oncoplastic breast surgery encompasses a range of techniques used to provide equitable oncological outcomes compared with standard breast surgery while, simultaneously, prioritizing aesthetic outcomes. While the outcomes of oncoplastic breast surgery are promising, it can add an extra complexity to the treatment paradigm of breast cancer and impact on decision-making surrounding adjuvant therapies, like chemotherapy and radiotherapy. As such, early discussions at the multidisciplinary team meeting with surgeons, medical oncologists, and radiation oncologists present, should be encouraged to facilitate best patient care.

Pre-pectoral breast reconstruction: early and long-term safety evaluation of 146 unselected cases of the early pre-pectoral era of a single-institution, including cases with previous breast irradiation and post-mastectomy radiation therapy

We re-evaluated acute and early-late toxicity-related factors among pre-pectoral immediate tissue expander/implant (TE/I) breast reconstruction (BR) unselected, first-era, cases, including previous breast radiation treatment and post-mastectomy radiation therapy (PMRT). A retrospective analysis of 146 (117 therapeutic and 29 prophylactic) pre-pectoral reconstructions, between 2012 and 2016, considered patient-related (age, body mass index [BMI], smoke-history, comorbidity, BRCA mutation), and treatment-related characteristics (previous irradiation, axillary surgery, PMRT, pre- and postoperative chemotherapy, endocrine therapy, and target-therapy). Safety was evaluated as acute and early-late complications, and TE/I failures. At multivariate analysis of the 146 cases (117 patients submitted to BR) a significant factor related to acute toxicity was: BMI ≥ 25 (31.3% [≥ 25] vs 8.8% [< 25]; OR 4.44, 95% CI 1.56-12.6; p = 0.003), while previous breast surgery on ipsilateral side presented a borderline significance (31.6% [previous surgery] vs 7.4% [no previous surgery]; OR 3.74, 95% CI 0.97-14.40; p = 0.055). Factors significantly related to TE/I failure were: current or previous smoking exposition (13.8% [smokers] vs 2.6% [non-smokers]; OR 7.32, 95% CI 1.37-39.08; p = 0.02) and preoperative chemotherapy (18.8% [yes] vs 3.5% [no]; OR 8.16, 95% CI 1.29-51.63; p = 0.026). At 4-year median follow-up, 3 deaths, 5 locoregional recurrences, and 14 distant metastases occurred. Immediate pre-pectoral BR is safe and effective, with low rates of acute and early-late complications. BMI and previous breast surgery were related to higher complications but not failure; smoking and preoperative chemotherapy were related to TE/I explant. Previous RT and PMRT were related neither to early-late toxicity nor failure.

Optimal reconstructive strategies in the setting of post-mastectomy radiotherapy - A systematic review and network meta-analysis

BACKGROUND

A third of breast cancer patients require mastectomy. In some high-risk cases postmastectomy radiotherapy (PMRT) is indicated, threatening reconstructive complications. Several PMRT and reconstruction combinations are used. Autologous flap (AF) reconstruction may be immediate (AF→PMRT), delayed-immediate with tissue expander (TE [TE→PMRT→AF]) or delayed (PMRT→AF). Implant-based breast reconstruction (IBBR) includes immediate TE followed by PMRT and conversion to permanent implant (PI [TE→PMRT→PI]), delayed TE insertion (PMRT→TE→PI), and prosthetic implant conversion prior to PMRT (TE→PI→PMRT).

AIM

Perform a network metanalysis (NMA) assessing optimal sequencing of PMRT and reconstructive type.

METHODS

A systematic review and NMA was performed according to PRISMA-NMA guidelines. NMA was conducted using R packages netmeta and Shiny.

RESULTS

16 studies from 4182 identified, involving 2322 reconstructions over three decades, met predefined inclusion criteria. Studies demonstrated moderate heterogeneity. Multiple comparisons combining direct and indirect evidence established AF-PMRT as the optimal approach to avoid reconstructive failure, compared with IBBR strategies (versus PMRT→TE→PI; OR [odds ratio] 0.10, CrI [95% credible interval] 0.02 to 0.55; versus TE→PMRT→PI; OR 0.13, CrI 0.02 to 0.75; versus TE→PI→PMRT OR 0.24, CrI 0.05 to 1.05). PMRT→AF best avoided infection, demonstrating significant improvement versus PMRT→TE→PI alone (OR 0.12, CrI 0.02 to 0.88). Subgroup analysis of IBBR found TE→PI→PMRT reduced failure rates (OR 0.35, CrI 0.15-0.81) compared to other IBBR strategies but increased capsular contracture.

CONCLUSION

Immediate AF reconstruction is associated with reduced failure in the setting of PMRT. However, optimal reconstructive strategy depends on patient, surgeon and institutional factors. If IBBR is chosen, complication rates decrease if performed prior to PMRT.

PROSPERO REGISTRATION

CRD 42020157077.

Early Postoperative Complications From National Surgical Quality Improvement Program: A Closer Examination of Timing and Technique of Breast Reconstruction

BACKGROUND

Despite the recent surge in rates of immediate breast reconstruction, there is a paucity of large multicenter studies to compare differences in morbidity after immediate versus delayed breast reconstruction. This study used the National Surgical Quality Improvement Program (NSQIP) to study the association between timing of breast reconstruction and complication rates, stratified by reconstructive modality.

STUDY DESIGN

The NSQIP database was used to identify breast reconstructions from 2005 to 2012. Rates of major complications were compared by timing within each reconstructive modality (implant vs autologous). Cohort differences in baseline characteristics and variables associated with increased complication rates were identified in bivariate analyses. A multivariable model was created to compare the association between the timing of reconstruction and major complications.

RESULTS

Of 24,506 postmastectomy reconstructions, 85.8% were immediate, 14.2% were delayed, 84% were implant, and 16% were autologous reconstructions. Overall, 10.0% of patients suffered a major complication. After stratification, only implant reconstructions showed a statistically higher complication rate with immediate (8.8%) reconstruction compared with delayed (5.3%) (odds ratio, 1.7, P < 0.01). There was no significant difference in complication rates between autologous immediate (18.4%) or delayed (19.0%) reconstructions. After controlling for baseline cohort differences and other risk factors, immediate reconstruction remained as an independent significant predictor of major complications in implant reconstructions (odds ratio, 1.8, P < 0.01).

CONCLUSIONS

Immediate rather than delayed breast reconstruction is associated with a significantly higher rate of major complications in implant reconstruction but not in autologous reconstruction. It is important to include these findings in the routine preoperative surgeon-patient discussion of reconstructive options.

Breast Implants and Radiation

One of the most influential factors in the success of breast reconstruction is whether or not radiation therapy has or will be performed. While traditional teaching is that all breasts treated with radiation therapy must be reconstructed with an autologous component, many reconstructive surgeons perform implant-based breast reconstruction without an autologous component and have success doing so. The purpose of this article is to explore the risks, benefits, and nuances of performing implant-based breast reconstruction in the setting of radiation therapy. The authors performed a review of the literature of all topics relevant to performing implant-based reconstruction with radiation therapy.

Hypofractionated postmastectomy radiotherapy with helical tomotherapy in patients with immediate breast reconstruction: dosimetric results and acute/intermediate toxicity evaluation

The aim of this study was to evaluate the dosimetry and toxicity of hypofractionation in postmastectomy radiotherapy (PMRT) with intensity-modulated radiotherapy (IMRT) in breast cancer (BC) patients. Stage II-III BC patients with implant-based immediate breast reconstruction received PMRT to the chest wall (CW) and to the infra/supraclavicular nodal region (NR) using a 15-fraction schedule (2.67 Gy/fraction) and helical IMRT (Tomotherapy^® System, Accuray Incorporated, Sunnyvale, CA). A score was assigned to each treatment plan in terms of planning target volume (PTV) coverage of CW and NR and the sparing of the organs at risk (OARs). The total score for each plan was calculated. Toxicity was prospectively assessed according to validated scales. Data from 120 consecutive patients treated in the period 2012-2015 were analysed with a median follow-up from the end of radiotherapy of 13.2 months (range 0.0-35 months). 70.8% (85/120) of the plans had high total scores as a result of an optimal coverage of both CW and RN and optimal sparing of all OARs. The maximum acute toxicity was of grade 2 in 36.7% of the cases. Early late toxicity was mild in the majority of cases. In the study population, helical tomotherapy-based IMRT produced optimal treatment plans in most cases. Acute and late toxicity was mild/moderate. Hypofractionated helical IMRT appears to be safe and feasible in the moderate term for PMRT.

Cardiac dose sparing and avoidance techniques in breast cancer radiotherapy

Breast cancer radiotherapy represents an essential component in the overall management of both early stage and locally advanced breast cancer. As the number of breast cancer survivors has increased, chronic sequelae of breast cancer radiotherapy become more important. While recently published data suggest a potential for an increase in cardiac events with radiotherapy, these studies do not consider the impact of newer radiotherapy techniques commonly utilized. Therefore, the purpose of this review is to evaluate cardiac dose sparing techniques in breast cancer radiotherapy. Current options for cardiac protection/avoidance include (1) maneuvers that displace the heart from the field such as coordinating the breathing cycle or through prone patient positioning, (2) technological advances such as intensity modulated radiation therapy (IMRT) or proton beam therapy (PBT), and (3) techniques that treat a smaller volume around the lumpectomy cavity such as accelerated partial breast irradiation (APBI), or intraoperative radiotherapy (IORT). While these techniques have shown promise dosimetrically, limited data on late cardiac events exist due to the difficulties of long-term follow up. Future studies are required to validate the efficacy of cardiac dose sparing techniques and may use surrogates for cardiac events such as biomarkers or perfusion imaging.

Differences in breast aesthetic outcomes due to radiation: A validated, quantitative analysis of expander-implant reconstruction

BACKGROUND

The potential ramifications of radiation use can be of particular concern in the breast reconstruction population, in which both surgical and aesthetic outcomes are important. Presently, there remains a paucity of data detailing the influence of radiation on specific reconstruction aesthetic outcomes.

OBJECTIVE

To conduct a quantitative evaluation of aesthetic outcomes for expander-implant breast reconstruction in radiated and nonradiated patients using a validated scoring scale.

METHODS

A series of consecutive expander-implant breast reconstruction operations performed by the senior author between 2004 and 2012 were reviewed. Four blinded members of the Division of Plastic and Reconstructive Surgery at Northwestern University (Illinois, USA) independently rated postoperative photographs of patients' breasts using a validated scoring scale with respect to five distinct aesthetic domains.

RESULTS

Of the 206 patients meeting the inclusion criteria, 69 received radiotherapy and 137 did not. The radiated cohort had lower scores in each aesthetic domain, with significant differences in contour (1.33 versus 1.51; P=0.041) and placement (1.45 versus 1.73; P<0.001). Linear regression analysis revealed a significant association between placement scores and radiation, and radiated patients had a significantly higher overall rate of complications.

DISCUSSION

Variances in scores may represent the relative difficulty of expansions and proper implant placement in irradiated tissue, with possible skin fibrosis and decreased flexibility hindering prosthesis manipulation.

CONCLUSION

Radiation adversely impacts breast contour and placement, with possible negative contributions to volume, scarring and inframammary fold definition, and results in higher rates of complications. Such detailed evaluation of the impact of radiation on aesthetics will enhance the management of patient expectations.

No difference in dose distribution in organs at risk in postmastectomy radiotherapy with or without breast implant reconstruction

The aim of this study was to quantify the variation in doses to organs at risk (ipsilateral lung and heart) and the clinical target volume (CTV) in the presence of breast implants. In this retrospective cohort study, patients were identified through the National Breast Cancer Register. Consecutive breast cancer patients undergoing mastectomy between 2009 and 2011 and completing a full course of postmastectomy radiotherapy (PMRT) were eligible. All included patients (n = 818) were identified in the ARIA© oncology information system and further stratified for immediate breast reconstruction (IBR+, n = 162) and no immediate breast reconstruction (IBR-, n = 656). Dose statistics for ipsilateral lung, heart and CTV were retrieved from the system. Radiation plans for patients with chest wall (CW) only (n = 242) and CW plus lymph nodes (n = 576) irradiation were studied separately.

The outcome variables were dichotomized as follows: lung, V_20Gy ≤ 30% vs. V_20Gy > 30%; heart, D_mean ≤ 5 Gy vs. D_mean > 5 Gy; CTV, V_95% ≥ median vs. V_95% < median.

In the univariate and multivariate regression models no correlation between potential confounders (i.e. breast reconstruction, side of PMRT, CW index) and the outcome variables was found. Multivariate analysis of CW plus lymph nodes radiation plans, for example, showed no association of breast reconstruction with dosimetric outcomes in neither lung nor heart- lung V_20Gy (odds ratio [OR]: 0.6, 95%CI, 0.4 to 1.0, p = 0.07) or heart D_mean (OR: 1.2, 95%CI, 0.5 to 3.1, p = 0.72), respectively.

CTV was statistically significantly larger in the IBR+ group (i.e. included breast implant), but no correlation between the implant type and dosimetric characteristics of the organs at risk was revealed.

In the current study, the presence of breast implants during postmastectomy radiotherapy was not associated with increased doses to ipsilateral lung and heart, but CTV definition and its dosimetric characteristics urge further evaluation.

Bilateral implant reconstruction does not affect the quality of postmastectomy radiation therapy

To determine if the presence of bilateral implants, in addition to other anatomic and treatment-related variables, affects coverage of the target volume and dose to the heart and lung in patients receiving postmastectomy radiation therapy (PMRT). A total of 197 consecutive women with breast cancer underwent mastectomy and immediate tissue expander (TE) placement, with or without exchange for a permanent implant (PI) before radiation therapy at our center. PMRT was delivered with 2 tangential beams + supraclavicular lymph node field (50Gy). Patients were grouped by implant number: 51% unilateral (100) and 49% bilateral (97). The planning target volume (PTV) (defined as implant + chest wall + nodes), heart, and ipsilateral lung were contoured and the following parameters were abstracted from dose-volume histogram (DVH) data: PTV D95% > 98%, Lung V20Gy > 30%, and Heart V25Gy > 5%. Univariate (UVA) and multivariate analyses (MVA) were performed to determine the association of variables with these parameters. The 2 groups were well balanced for implant type and volume, internal mammary node (IMN) treatment, and laterality. In the entire cohort, 90% had PTV D95% > 98%, indicating excellent coverage of the chest wall. Of the patients, 27% had high lung doses (V20Gy > 30%) and 16% had high heart doses (V25Gy > 5%). No significant factors were associated with suboptimal PTV coverage. On MVA, IMN treatment was found to be highly associated with high lung and heart doses (both p < 0.0001), but implant number was not (p = 0.54). In patients with bilateral implants, IMN treatment was the only predictor of dose to the contralateral implant (p = 0.001). In conclusion, bilateral implants do not compromise coverage of the target volume or increase lung and heart dose in patients receiving PMRT. The most important predictor of high lung and heart doses in patients with implant-based reconstruction, whether unilateral or bilateral, is treatment of the IMNs. Refinement of radiation techniques in reconstructed patients who require comprehensive nodal irradiation is warranted.

Current status of implant-based breast reconstruction in patients receiving postmastectomy radiation therapy

BACKGROUND

Increasing numbers of patients with breast cancer are being treated with postmastectomy radiation therapy. The author reviewed the literature to determine the clinical impact of this increasing use of postmastectomy radiation therapy in patients with breast cancer who desire implant-based breast reconstruction.

METHODS

The author searched the MEDLINE database for articles on breast reconstruction and radiation therapy published between January of 2008 and June of 2011 and reviewed the abstracts of those articles to identify articles with information about the impact of irradiation on implant-based breast reconstruction. This subgroup of articles was reviewed in detail.

RESULTS

Two hundred eighty-five articles were identified. Nineteen articles were reviewed in detail. Eight articles provided level III evidence; one provided level I or II evidence from high-quality multicenter or single-center randomized controlled trials or prospective cohort studies. Two articles provided level IV evidence from case series and were included in the review because they offered a novel approach or perspective. The most recent studies find a significant need for unplanned or major corrective surgery in irradiated breasts reconstructed with implants. Although breast implant reconstruction in irradiated breasts is associated with high rates of complications, only a minority of patients require conversion to an autologous tissue flap.

CONCLUSION

Although the majority of patients who undergo implant-based reconstruction and irradiation ultimately keep the implant reconstruction, patient surveys show that irradiation has a significantly negative effect on patient satisfaction.

Quantifying dose to the reconstructed breast: can we adequately treat?

To evaluate how immediate reconstruction (IR) impacts postmastectomy radiotherapy (PMRT) dose distributions to the reconstructed breast (RB), internal mammary nodes (IMN), heart, and lungs using quantifiable dosimetric end points. 3D conformal plans were developed for 20 IR patients, 10 autologous reconstruction (AR), and 10 expander-implant (EI) reconstruction. For each reconstruction type, 5 right- and 5 left-sided reconstructions were selected. Two plans were created for each patient, 1 with RB coverage alone and 1 with RB + IMN coverage. Left-sided EI plans without IMN coverage had higher heart Dmean than left-sided AR plans (2.97 and 0.84 Gy, p = 0.03). Otherwise, results did not vary by reconstruction type and all remaining metrics were evaluated using a combined AR and EI dataset. RB coverage was adequate regardless of laterality or IMN coverage (Dmean 50.61 Gy, D95 45.76 Gy). When included, IMN Dmean and D95 were 49.57 and 40.96 Gy, respectively. Mean heart doses increased with left-sided treatment plans and IMN inclusion. Right-sided treatment plans and IMN inclusion increased mean lung V(20). Using standard field arrangements and 3D planning, we observed excellent coverage of the RB and IMN, regardless of laterality or reconstruction type. Our results demonstrate that adequate doses can be delivered to the RB with or without IMN coverage.

Quantifying the impact of immediate reconstruction in postmastectomy radiation: a large, dose-volume histogram-based analysis

PURPOSE

To assess the impact of immediate breast reconstruction on postmastectomy radiation (PMRT) using dose-volume histogram (DVH) data.

METHODS AND MATERIALS

Two hundred forty-seven women underwent PMRT at our center, 196 with implant reconstruction and 51 without reconstruction. Patients with reconstruction were treated with tangential photons, and patients without reconstruction were treated with en-face electron fields and customized bolus. Twenty percent of patients received internal mammary node (IMN) treatment. The DVH data were compared between groups. Ipsilateral lung parameters included V20 (% volume receiving 20 Gy), V40 (% volume receiving 40 Gy), mean dose, and maximum dose. Heart parameters included V25 (% volume receiving 25 Gy), mean dose, and maximum dose. IMN coverage was assessed when applicable. Chest wall coverage was assessed in patients with reconstruction. Propensity-matched analysis adjusted for potential confounders of laterality and IMN treatment.

RESULTS

Reconstruction was associated with lower lung V20, mean dose, and maximum dose compared with no reconstruction (all P<.0001). These associations persisted on propensity-matched analysis (all P<.0001). Heart doses were similar between groups (P=NS). Ninety percent of patients with reconstruction had excellent chest wall coverage (D95 >98%). IMN coverage was superior in patients with reconstruction (D95 >92.0 vs 75.7%, P<.001). IMN treatment significantly increased lung and heart parameters in patients with reconstruction (all P<.05) but minimally affected those without reconstruction (all P>.05). Among IMN-treated patients, only lower lung V20 in those without reconstruction persisted (P=.022), and mean and maximum heart doses were higher than in patients without reconstruction (P=.006, P=.015, respectively).

CONCLUSIONS

Implant reconstruction does not compromise the technical quality of PMRT when the IMNs are untreated. Treatment technique, not reconstruction, is the primary determinant of target coverage and normal tissue doses.

Local breast cancer recurrence after mastectomy and immediate breast reconstruction for invasive cancer: a meta-analysis

BACKGROUND

The main priorities in the surgical treatment of patients with breast cancer are to achieve cure, local control and prevent recurrence. It is increasingly important to address quality of life and self-image with women undergoing surgical intervention for breast cancer. There is a lack of consensus as to the oncologic safety of immediate breast reconstruction (IBR). The purpose of this paper is to systematically review the literature and compare the frequency of recurrence in patients with and without IBR following mastectomy for breast cancer.

METHODS

Two independent investigators searched PubMed, Embase, and the Cochrane database using predefined search terms. After application of inclusion and exclusion criteria, 10 articles remained. Each article was assessed for quality. Relevant data was collected including recurrence rates, cancer stage, type of mastectomy and reconstruction, adjuvant treatments, and duration of follow-up.

RESULTS

Inter-rater reliability was good at 74% (95% CI: 0, 93%). There was no evidence of study heterogeneity (p for Q-statistic=0.34 and I(2)=12%). The OR ratio for recurrence of breast cancer for mastectomy with IBR as compared to mastectomy alone was 0.98 (95% CI: 0.62, 1.54).

CONCLUSION

This meta-analysis demonstrated no evidence for increased frequency of local breast cancer recurrence with IBR compared with mastectomy alone.

Dose to level I and II axillary lymph nodes and lung by tangential field radiation in patients undergoing postmastectomy radiation with tissue expander reconstruction

BACKGROUND

To define the dosimetric coverage of level I/II axillary volumes and the lung volume irradiated in postmastectomy radiotherapy (PMRT) following tissue expander placement.

METHODS AND MATERIALS

Twenty-three patients were identified who had undergone postmastectomy radiotherapy with tangent only fields. All patients had pre-radiation tissue expander placement and expansion. Thirteen patients had bilateral expander reconstruction. The level I/II axillary volumes were contoured using the RTOG contouring atlas. The patient-specific variables of expander volume, superior-to-inferior location of expander, distance between expanders, expander angle and axillary volume were analyzed to determine their relationship to the axillary volume and lung volume dose.

RESULTS

The mean coverage of the level I/II axillary volume by the 95% isodose line (V(D95%)) was 23.9% (range 0.3 - 65.4%). The mean Ipsilateral Lung V(D50%) was 8.8% (2.2-20.9). Ipsilateral and contralateral expander volume correlated to Axillary V(D95%) in patients with bilateral reconstruction (p = 0.01 and 0.006, respectively) but not those with ipsilateral only reconstruction (p = 0.60). Ipsilateral Lung V(D50%) correlated with angle of the expander from midline (p = 0.05).

CONCLUSIONS

In patients undergoing PMRT with tissue expanders, incidental doses delivered by tangents to the axilla, as defined by the RTOG contouring atlas, do not provide adequate coverage. The posterior-superior region of level I and II is the region most commonly underdosed. Axillary volume coverage increased with increasing expander volumes in patients with bilateral reconstruction. Lung dose increased with increasing expander angle from midline. This information should be considered both when placing expanders and when designing PMRT tangent only treatment plans by contouring and targeting the axilla volume when axillary treatment is indicated.

Immediate reconstruction with implants in women with invasive breast cancer does not affect oncological safety in a matched cohort study

Physicians are still concerned about the oncological safety regarding immediate breast reconstruction (IBR) in breast cancer patients. This study aimed to evaluate possible differences between local, regional, and distant recurrences between women having implant-based reconstruction versus women operated with mastectomy alone. Secondary aims were to evaluate time to oncological treatment as well as disease-free and breast-cancer-specific survival. In a retrospective cohort designed study, 300 reconstructed patients with invasive breast cancer were matched with 300 patients from the population-based Regional Breast Cancer Register of the Stockholm-Gotland health-care region operated with mastectomy alone. They were matched for age, tumor size, nodal stage, and year of operation. Also included were patients treated with neoadjuvant chemotherapy and postoperative radiotherapy. The median follow-up for both the groups was 11.5 years (range 2-20). There were no significant differences in the local recurrence rate, 8.2% in the IBR group and 9.0% in the control group or in the regional recurrence rate, 8.2% versus 9.7%. Distant metastases occurred more frequently in the control group (27.1%) when compared to the IBR group (20.3%). There were no significant differences in time to treatment or in complications rate. Breast cancer mortality was 17% for the IBR group and 23% in the control group during follow-up. This long-term follow-up survey with a well-matched control group demonstrates that IBR with implants is safe to offer patients with invasive breast cancer without any negative effect on the oncological safety.