Introduction: Neoadjuvant radiotherapy (NART) as part of a multi-modality approach for locally advanced breast cancer (LABC) requires further investigation. Importantly, this approach may allow for a single-staged surgical procedure, with mastectomy and immediate autologous reconstruction. Multiple other potential benefits of NART include improved pathological downstaging of breast disease, reduced overall treatment time, elimination of time period with breast tissue deficit and improved patient satisfaction. Methods: This is a retrospective multi-institutional review of patients with LABC and high-risk breast disease undergoing NART. Eligible patients sequentially underwent neoadjuvant chemotherapy (NACT) with or without HER2-targeted therapy, NART, followed by mastectomy with immediate autologous breast reconstruction (BR) 4-to 6 weeks post-completion of radiotherapy. Patient and tumour characteristics were analysed using descriptive statistics. Surgical complications were assessed using the Clavien-Dindo Classification (Ann Surg 2004; 240: 205). Results: From 3/2013 to 9/2019, 153 patients were treated with NART. The median age was 47 years (IQR 42-52), with median body mass index of 27. Eighteen patients experienced Grade 3 acute surgical complications. This included 13 Grade 3B breast-site events and 9 Grade 3B donor-site events, where further surgical intervention was required for management of wound infection, wound dehiscence, flap or mastectomy skin necrosis, haematoma and internal mammary venous anastomotic thrombosis. No autologous flap loss was observed. Conclusion: Neoadjuvant radiotherapy facilitates a single-stage surgical procedure with mastectomy and immediate autologous BR, eliminating the delay to reconstructive surgery and thus shortening a woman's breast cancer journey. The findings of this review support the use of NART, with comparable rates of surgical complications to standard sequencing.

Purpose The aim of this retrospective study was to investigate the use of a radiopaque tissue fiducial marker (TFM) in the treatment of prostate cancer patients who undergo post-prostatectomy radiotherapy (PPRT). TFM safety, its role and benefit in quantifying the set-up uncertainties in patients undergoing PPRT image-guided radiotherapy were assessed. Materials and Methods A total of 45 consecutive PPRT patients underwent transperineal implantation of TFM at the level of vesicourethral anastomosis in the retrovesical tissue prior to intensity-modulated radiotherapy. Prostate bed motion was calculated by measuring the position of the TFM relative to the pelvic bony anatomy on daily cone-beam computed tomography. The stability and visibility of the TFM were assessed in the initial 10 patients. Results No postoperative complications were recorded. A total of 3,500 images were analysed. The calculated prostate bed motion for bony landmark matching relative to TFM were 2.25 mm in the left-right, 5.89 mm in the superior-inferior, and 6.59 mm in the anterior-posterior directions. A significant 36% reduction in the mean volume of rectum receiving 70 Gy (rV 70 ) was achieved for a uniform planning target volume (PTV) margin of 7 mm compared with the Australian and New Zealand Faculty of Radiation Oncology Genito-Urinary Group recommended PTV margin of 10 mm. Conclusion The use of TFM was safe and can potentially eliminate set-up errors associated with bony landmark matching, thereby allowing for tighter PTV margins and a consequent favourable reduction in dose delivered to the bladder and rectum, with potential improvements in toxicities.

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; the 80-degree collimator angle arc is fixed for all plans. The use of jaw tracking technique is chosen during the optimization process, which is commercially available. The two prescription dose levels of the planning target volumes were 70 Gy and 63 Gy in 35 fractions, using SIB. Results: The mean PTV 70 Gy and PTV 63 Gy doses were 65.83 Gy and 61.3 Gy for all plans respectively, extracted from the dose-volume histogram (DVH). Although the (60, 300 , and 80) plan shows slightly the lowest CI (0.96 and 0.94 for both PTV 70 Gy and PTV 63 Gy, respectively) and HI (0.06 and 0.14 for both PTV 70 Gy and PTV 63 Gy, respectively); the average values of conformity and homogeneity indexes were not significantly different for all plans. In addition, in terms of sparing of normal structures, the average DVHs showed that the maximum doses received by organs at risk were in the plan with highest collimator angles (60, 300 , and 80), and the minimum doses were in favor of the plan with the lowest collimator angles (15 , 345 , and 80). The averaged body integral doses were almost equivalent in all plans ranged between 130.38 Gy.L to 132.01 Gy.L. Conclusion: The dosimetric results for this study; indicated that the DVH parameters for the normal organs are dependent on the chosen collimator angles for all VMAT fields. As the collimator angle increases, the normal tissue doses slightly increase consequently. The PTVs HI and CI of all plans were almost the same, regardless of the collimator angles. The 80degree collimator angle arc gives additional sparing of OAR and more homogeneous PTV doses. Therefore, in order to improve the plan quality in NPC VMAT with SIB the planning physicist must select the optimal collimator angles that provide the best PTV coverage with that clinically acceptable OAR doses.

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Introduction Delayed breast reconstructions are preferred if post mastectomy radiotherapy is indicated due to lower complication rates compared to immediate permanent implant or autologous reconstructions (AR) but cosmetic outcomes are inferior. Radiotherapy has a deleterious effect on implants and autologous tissue and often an interim tissue expander is place which has inherent pain and complications. However, neoadjuvant radiotherapy (NART) prior to surgery allows for definitive oncological surgery to be performed with an immediate AR in a single operation and the avoidance of a temporary expander. The aim of this study is to assess the safety and downstaging impact of NART. Methods This is a prospective review of patients who underwent NART at GenesisCare Victoria, the Austin and the Alfred hospital. 59 LABC patients (median age 49.2 years) were divided into two groups; clinically staged and pathologically staged for reporting. There were 15 pathologically staged patients (pStage 2A-3C) and 43 clinically staged patients (cStage 2A-3B). All patients initially underwent NACT, followed by NART (median dose 50.4Gy in 28 fractions) to the breast, supraclavicular fossa and level 3 axilla with or without coverage of their Level 1 and 2 axilla, and/or internal mammary nodes. Approximately 6 weeks after completing NART, patients underwent definitive surgery and AR. Results All patients completed their NART with minimal toxicity and no break in treatment. 55 patients had a skin-sparing mastectomy (SSM) and 3 patients had a modified radical mastectomy. All clinically staged patients underwent an AD. ARs with a DIEP flap were performed in the majority of patients (51). The average length of hospitalisation was 6.2 days. The Miller Payne (MP) scoring index was used to record pathological responses in clinically staged patients. Overall 36 patients achieved significant downstaging of their disease, with MP scores of 5/5 for 20 and 4/5 for 16. Only 1 patient failed to achieve any downstaging with a MP score of 1/5. All 12 Her2 positive patients, 3/5 Triple negative patients and 5/26 Luminal A/B patients achieved a MP score of 5/5. All patients achieved R0 resection margins. This included 6 patients who had initial cT4 disease (cT4a X2, cT4b X1 and cT4d X3). 15 patients had initial cN2/3 disease and all successfully underwent their axillary dissections with R0 resections achieved. 10/15 had no involved axillary nodes with significant scarring seen in 6. 5/15 had residual involved nodes with significant scarring seen in 3 patients. Post surgical toxicities were graded using Clavien-Dindo classification. 8 significant grade 3 toxicities were seen in 6 patients, with no grade 4 or 5 toxicities. No patients developed DVT or PE. No flap losses were seen. Median follow up is 23 months. Cosmesis was rated as good to excellent in all cases. 1 patient developed simultaneous loco-regional and distant recurrence with another 3 patients developing distant metastases only. Conclusion This review demonstrated that NART is a safe technique, which has not lead to an increase in surgical complication rates or resulted in a detriment in cosmetic outcome. NART can achieve a shorter, simpler reconstructive journey for patients. Citation Format: Baker C, Chao MW, Jassal S, Neoh D, Bevington E, Hyett A, Grinsell D, Loh SW, Zantuck N, Stoney D, Foley C, Law M, Chew G, Yu V, Cheng M, Guerrieri M, Taylor K, Chipman M, Cokelek M, Lim Joon D, Foroudi F. The safety and pathological impact of neoadjuvant radiotherapy for local advanced breast cancer undergoing mastectomy and autologous reconstruction [abstract]. In: Proceedings of the 2017 San Antonio Breast Cancer Symposium; 2017 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2018;78(4 Suppl):Abstract nr P2-11-16.

Reconstruction failure (RF) is defined as any unplanned implantation/ replacement/adjustment of implants, or complete loss/necrosis of autologous flaps. Severe capsular contracture (CC) is defined as requiring capsulotomy or capsulectomy. Univariate and multivariate analysis were performed using logistic regression analysis. Results: In total, 265 patients undergoing 274 IBR were reviewed, including 262 breasts receiving retro-pectoral IBR-i with or without latissimus dorsi flaps and 12 autologous flaps only. The median age was 40 years. A total of 55 breasts received RT and CTV was defined to include entire implants or flaps. In total, RF events occurred in 15 (5.5%) breasts and the most common cause (60%) of RF was implant exposure and/or infection. Univariate analysis showed that adjuvant chemotherapy (CT) and BMI were both significant risk factors for RF while RT was not (OR 0.995, 95% CI 0.271-3.656, p Z 0.994). Multivariate analysis showed that only adjuvant CT was the significant risk factor for RF (OR 6.283, 95% CI 1.332-29.643, p Z 0.02). CC was evaluated in 262 breasts with IBR-i. Severe CC occurred in 11 patients, with 7 in the RT group. Multivariate analysis showed that RT was the only significant risk factor for developing severe CC (OR 4.000, 95% CI 1.017-15.738, p Z 0.047). After a median follow-up of 44 months, 6 LRR events were observed, including 2 in chestwall, 1 in nipple-areolar and 3 in axilla. No recurrence in pectoral muscles, ribs or intercostal muscles was observed. None of recurrence occurred outside the border of ESTRO CTV-chest wall recommendation. The 5-year recurrence from survival (RFS), local-regional RFS and overall survival were 93.0%, 98.2% and 98.7%, respectively. Conclusion: IBR after BC surgery yields a low rate of RF and severe CC. Adjuvant CT was associated with increased risk of RF. Post-operative RT remains a risk factor for severe CC. Pattern of LRR in our study supports the oncological safety of ESTRO delineation guideline. Further study is needed to confirm if the new delineation will help to decrease the RTrelated complications in patients with IBR.

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