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3D-conformal Accelerated Partial Breast Irradiation treatment planning: the value of surgical clips in the delineation of the lumpectomy cavity
Maia Dzhugashvili, Elodie Tournay, Charlotte Pichenot, Ariane Dunant, Eduardo Pessoa, Adel Khallel, Sébastien Gouy, Catherine Uzan, Jean-Rémy Garbay, Fran?oise Rimareix, Marc Spielmann, Philippe Vielh, Hugo Marsiglia, Céline Bourgier
Radiation Oncology , 2009, DOI: 10.1186/1748-717x-4-70
Abstract: Forty CT-based 3D-APBI plans were retrieved on which a total of 4 radiation oncologists, two trainee and two experienced physicians, outlined the lumpectomy cavity. The inter-observer variability of LC contouring was assessed when the CTV was defined as the delineation that encompassed both surgical clips and remodelled breast tissue.The conformity index of tumour bed delineation was significantly improved by the placement of surgical clips within the LC (median at 0.65). Furthermore, a better conformity index of LC was observed according to the experience of the physicians (median CI = 0.55 for trainee physicians vs 0.65 for experienced physicians).The placement of surgical clips improved the accuracy of lumpectomy cavity delineation in 3D-APBI. However, a learning curve is needed to improve the conformity index of the lumpectomy cavity.Accelerated Partial Breast Irradiation (APBI) is still under investigation to demonstrate equivalence to whole breast irradiation in terms of local control. Among the different APBI techniques (invasive or non-invasive), 3D-conformal APBI is widely used given its accessibility in radiotherapy centres [1]. However, several issues related to this technique still warrant investigation: e.g. the identification and contouring of the lumpectomy cavity (LC), the patient's set-up and optimal dose determination. The definition of the lumpectomy cavity is an essential part of 3D-conformal APBI treatment planning as the irradiation is confined to a limited volume of breast tissue adjacent to the lumpectomy cavity. Unlike intra-operative partial breast irradiation, LC determination is critical as treatment delivery is delayed after breast surgery. In 3D-APBI, the GTV (Gross Tumour Volume) and CTV (Clinical Target Volume) are generally defined as the contouring of a seroma within the lumpectomy cavity, expanded by a 1 cm margin [2,3]. However, the delineation of the seroma could vary among different observers and even among experienced ones[4].I
Frozen Section Analysis of Breast Lumpectomy Margins  [PDF]
Fatma Khinaifis Althoubaity, Adnan Merdad, Nouf Yahya Akeel, Nisar Haider Zaidi, Abdullah Omar Sultan
Surgical Science (SS) , 2017, DOI: 10.4236/ss.2017.86029
Abstract: Objectives: To evaluate breast lumpectomy margins by frozen section in breast conservation surgery. Methods: A retrospective study of frozen section of lumpectomy margins of one hundred ten patients was done at King Abdulaziz University Hospital from June 2007 to June 2013. All patients underwent lumpectomy + Sentinel lymph node biopsy. Patient records were studied for location of mass in breast, size of mass, site of breast, pre or postmenopausal, frozen section margins, new frozen section margins, permanent margins, reoperation. Complications like skin necrosis, numbness, and wound infection were studied. Result: Majority were Saudis (64.5%). Left breast was involved in 60%. Upper outer quadrant was involved in majority (51.9%). Size of mass was less than 1 cm in 14.8% cases, 1 - 2.9 cm in 43.5%, 3 - 4 cm in 13%, more than 4 cm in 10.2%. Lumpectomy plus sentinel lymph node biopsy was done in 96.4% and lumpectomy and axillary lymph node dissection was done in 1.8% cases. Gross margins were positive in 17.3% and frozen margins were positive in 28.2%. New margin on frozen section were positive in 3.6% and negative in 79.1%. Permanent section histology showed positive margins in 5.5% and negative in 94.5% cases. Re-operation was done in 7.3%. Lympho-vascular margins were positive in 20.9%. Skin necrosis was found in 2.2%, numbness was found in 4.4%, wound infection was in 2.2%. Conclusion: Lumpectomy margins with frozen section reduce re-operation and recurrence.
Intraoperative radiation therapy in the treatment of early-stage breast cancer utilizing xoft axxent electronic brachytherapy
Adam Dickler, Olga Ivanov, Darius Francescatti
World Journal of Surgical Oncology , 2009, DOI: 10.1186/1477-7819-7-24
Abstract: We report on the first patient treated with XB to deliver IORT.IORT treatment utilizing XB is feasible and can be accomplished with a total procedure time of approximately 2 hours.Further research on XB and other methods of IORT is needed to establish clinical efficacy and safety for patients with early-stage breast cancer.Several large randomized trials with extended follow-up have shown that breast conserving therapy (BCT) offers equivalent overall survival to modified radical mastectomy in patients with early stage breast cancer [1,2]. Studies have also shown that in certain parts of the United States, as few as 10% of eligible patients receive BCT [3,4]. Instead, some women are treated with mastectomy and others receive lumpectomy alone. This is especially common for women who live at an increased distance from radiation centers [5,6]. The logistical difficulties that accompany a 6–7 week course of whole breast external beam radiation (EBRT) are believed to be the main deterrent to patients receiving radiation therapy. Although radiation therapy is burdensome, it is an important component of BCT that cannot be safely omitted. EBRT has been shown to both decrease the risk of local recurrence and also to improve overall survival compared to surgery alone [7].In an effort to overcome the barriers to BCT, alternative methods of delivering radiation therapy have been explored. In contrast to standard EBRT, which treats the whole breast, accelerated partial breast irradiation (APBI) delivers radiation to the lumpectomy bed plus a 1–2 cm margin only. By decreasing the volume of treatment and increasing the daily fraction size of the radiation, treatment can be accomplished in one week rather than the standard 6–7 weeks.The method of APBI with the longest published experience is multi-catheter interstitial brachytherapy. In this technique, several rows of catheter needles are placed around the lumpectomy bed and loaded with radiation sources. Multi-catheter interstitial
Breast Surgery with Application of Doughnut Mastopexy Lumpectomy Technique  [PDF]
Kyoichi Matsuzaki
Modern Plastic Surgery (MPS) , 2012, DOI: 10.4236/mps.2012.24022
Abstract: Purpose: Doughnut mastopexy lumpectomy (DML) is a breast resection technique in which a tissue segment is removed and the breast reshaped through a doughnut-shaped de-epithelialized periareolar area. In this study, we attempted to determine whether the DML technique could be useful for other types of breast surgery, in addition to breast cancer lumpectomy. Methods: This study examined a total of 4 patients who underwent the DML technique and were followed up for at least 1 year postoperatively. One patient underwent phyllodes tumor resection, 1 patient underwent removal of a siliconoma, and 2 patients underwent breast reduction mammaplasty. Results: This method enabled en-bloc removal of a large tissue mass or large foreign body that could not be removed through a short periareolar incision. The surgical method of this study enabled the extent of de-epithelialization to be changed according to the size and location of the mass to be excised; good cosmetic results were also obtained. In addition, the surgical method enabled the facile excision of tumors and foreign materials. Conclusions: The DML technique is a useful surgical method that is applicable to other breast surgeries, in addition to breast cancer surgery.
Breast dose heterogeneity in CT-based radiotherapy treatment planning  [cached]
Prabhakar R,Rath G,Julka P,Ganesh T
Journal of Medical Physics , 2008,
Abstract: The aim of this study was to evaluate the breast dose heterogeneity in CT-based radiotherapy treatment planning and to correlate with breast parameters. Also, the number of slices required for treatment planning in breast cancer by tangential field technique has been assessed by comparing the treatment plans according to International Commission on Radiation Units and Measurement (ICRU) 50 guidelines (1993) for single-slice, three-slice, and multi-slice (3D) planning . Sixty women who underwent isocentric tangential field breast radiotherapy were included in this study. The plans were optimized and analyzed with dose volume histograms. Sixty-three percent of the single-slice plans and 26.7% of the three-slice plans showed poor dose homogeneity as compared to the 3D plans. Dose inhomogeneity correlated better with breast volume (r 2 = 0.43) than the chest wall separation (r 2 = 0.37) and breast area product (r 2 = 0.36). Similarly, breast volume correlated better with breast area product (r 2 = 0.80) than with chest wall separation (r 2 = 0.56). Breast volume can be approximated to breast area product from the relation, breast volume = [(breast area product x 8.85) 120.05]. The results of this study showed that most of the cases require 3D planning for breast cancer. It also showed that patients with large breast are prone to have more dose inhomogeneity with standard tangential field radiotherapy. In centers where 3D planning is not possible due to lack of facilities or workload, three slices-based planning can be performed to approximate the dosimetric advantage of 3D planning.
PET/CT in radiation therapy & treatment planning
Amin Zonoozi
Iranian Journal of Nuclear Medicine , 2010,
Abstract: Radiation therapy (RT), staging, treatment planning, monitoring and evaluation of response are traditionally based on Computed Tomography (CT) and Magnetic Resonance Imaging (MRI). These radiological investigations have the significant advantage to show the anatomy with a high resolution, being also called anatomical imaging. In recent years, so called biological imaging methods which visualize metabolic pathways have been developed. To date, the most prominent biological imaging system in use is Positron Emission Tomography (PET), whose diagnostic properties have clinically been evaluated for years. The combination of PET and CT in a single system (PET/CT) to form an inherently fused anatomical and functional dataset has provided an imaging modality which could be used as the prime tool in the delineation of tumor volumes and the preparation of patient treatment plans, especially when integrated with virtual simulation. This powerful method offer complementary imaging of various aspects of tumor biology. The aim of this review is to discuss the valences and implications of PET/CT in RT. The focus will be on evaluation of the following topics: the role of biological imaging for tumor tissue detection/delineation of the gross tumor volume (GTV) and for the visualization of heterogeneous tumor biology. The role of fluorodeoxyglucose-PET in lung will be discussed. There was also evidence for utility of PET in head and neck cancers, lymphoma and in esophageal cancers, with promising preliminary data in many other cancers. The best available approach employs integrated PET/CT images, acquired on a dual scanner in the radiotherapy treatment position after administration of tracer according to a standardized protocol, with careful optimization of images within the RT planning system and carefully considered rules for contouring tumor volumes. The impact of amino acids (AA)-PET in target volume delineation of brain gliomas was discussed. Furthermore, it is summarized the data of the literature about tumor hypoxia and proliferation visualized by PET. It concluded that regarding treatment planning in radiotherapy, PET offers advantages in terms of tumor delineation and the description of biological processes. PET/CT will play an increasing valuable role in RT planning for a wide range of cancers.
Redefining Lumpectomy Using a Modification of the “Sick Lobe” Hypothesis and Ductal Anatomy  [PDF]
W. Dooley,J. Bong,J. Parker
International Journal of Breast Cancer , 2011, DOI: 10.4061/2011/726384
Abstract: Objectives. The “Sick Lobe” hypothesis states that breast cancers evolve from entire lobes or portions of lobes of the breast where initiation events have occurred early in development. The implication is that some cancers are isolated events and others are truly multi-focal but limited to single lobar-ductal units. Methods. This is a single surgeon retrospective review of early stage breast cancer lumpectomy patients treated from 1/2000 to 2/2005. Ductal endoscopy was used direct lumpectomy surgical margins by defining ductal anatomy and mapping proliferative changes within the sick lobe for complete excision. Results. Breast conservation surgery for stage 0–2 breast cancer with an attempt to perform endoscopy in association with therapeutic lumpectomy was performed in 554 patients (successful endoscopy in 465 cases). With an average followup of >5 years for the entire group, annual hazard rate for local failure in traditional lumpectomy without ductal mapping was 0.97%/yr. and for lumpectomy with ductal mapping and excision of entire sick lobe was 0.18%/yr. With endoscopy, 42% of patients were found to have extensive disease within their “sick lobe.” Conclusions. Targeting breast cancer lumpectomy using endoscopy and excision of regional associated proliferation seems associated with lower recurrence in this non-randomized series. 1. Introduction The “Sick Lobe” hypothesis was proposed by Tibor Tot in 2005 [1]. His work was really a culmination of collecting relevant clinical and pathologic observations of the last century and a half. His first observations and predictions were based upon DCIS. The breast is defined as a single organ made of multiple lobes. Each lobe is identified by a single orifice on the nipple papilla connecting to branching tree of ducts and hundreds to thousands of individual lobules in the periphery. He proposed that for many cases of DCIS (especially extensive ones) the initiating events of carcinogenesis occurred perhaps as early as in the womb. Then throughout life as the lobe both grew and contracted from hormonal and other influences progression would occur at varying rates in different regions of the ductal tree. This led to the situation of apparent multifocality within the ductal tree and pathologic “skips” between DCIS patches. With further whole mount examination, extensive dissection of extensive intraductal component small invasive cancer cases, and multifocal invasive cancers, the findings support this theory [2–7]. Further molecular studies would seem to indicate that serious adverse genetic events are present
Analysis of CT Images of Liver for Surgical Planning
American Journal of Biomedical Engineering , 2012, DOI: 10.5923/j.ajbe.20120202.05
Abstract: We developed a Computer Assisted Surgery system which prepared a virtual environment for a physician to interact with the liver and decide on the therapy planning. It was composed of three modules: liver segmentation, vessel extraction, and simulator. We proposed a semi-automatic method to segment the liver. Hepatic veins, portal veins, and hepatic arteries were extracted from multi-phase CT datasets. The simulator visualized the segmented objects and provided for a physician a virtual scalpel to cut the liver. Initially, a transparent view of the liver was shown to the physician that revealed the location of the vascular structures. During the surgery, a toggling option made it possible to switch between a transparent and an opaque view. The width, height, and depth of the cut could be changed by user interaction. The proposed system is a framework which can later be extended to a complete system for analysis of hepatic diseases and therapy planning.
The Role of CT-Based Radiotherapy Planning on Dosimetric Correction
S.R Mahdavi,A.R Nikoofar,H.R Mirzaei,B Mofid
Iranian Journal of Radiology , 2009,
Abstract: Background/Objective: The dose distribution is affected by tissue inhomogeneities. The objective of this study was a dosimetric evaluation of the potential corrective role of computed tomography (CT) data in radiotherapy treatment planning (RTP) for various anatomical sites of the body (head and neck, abdominopelvis and thorax), separately."nPatients and Methods: Fifty-four cases of head and neck, pelvis, abdomen and breast cancers were included in this study. All of the patients were scanned with the same CT machine. Each case was planned with and without CT-based density correction by a two-dimensional ALFARD RTP system. Analyses of dosimetric parameters were performed for with and without inhomogeneity corrections based on the effective path length method. Dosimetric parameters were dose uniformity (Te), the average (Davg), minimum (Dmin) and maximum (Dmax) doses for both the planning target volumes and organs at risk. These parameters with and without CT-based density correction were compared in the head and neck, abdominopelvic and thoracic regions, separately."nResults: The mean difference of Te and Davg between these two methods was statistically significant in the thoracic region (7.13±5.55; p=0.001 for Te and 4.65±6.59; p=0.04 for Davg). Measurements of Te, Davg, Dmin and Dmax in the head and neck and abdominopelvic regions showed no statistically significant differences between the two methods (all p values≥0.05)."nConclusion: In some parts of the body, if the CT correction for density variation was not applied, the dose deviations could be out of the tolerance limits defined by the standards for tumors and normal tissues.
The effect of intraoperative specimen inking on lumpectomy re-excision rates
Mansher Singh, Gayatri Singh, Kevin T Hogan, Kristen A Atkins, Anneke T Schroen
World Journal of Surgical Oncology , 2010, DOI: 10.1186/1477-7819-8-4
Abstract: All women undergoing lumpectomy for breast cancer by a single surgeon between 03/2007 - 02/2009 were included. Lumpectomies underwent standard inking (SI) after surgery by a pathologist from 03/2007-02/2008 while intraoperative inking (II) with direct surgeon input was done from 03/2008-02/2009. Rates of margin positivity and re-excision were compared between these methods.65 patients were evaluated, reflecting SI in 39 and II in 26 cases. Margin positivity rates of 46% [SI] vs. 23% [II] (p = 0.06) and re-excision rates of 38% [SI] vs. 19% [II] were observed. Residual disease at re-excision was found in 27% [SI] vs. 67% [II] of cases.Intraoperative inking in this practice offered a simple way to reduce re-excision rates after lumpectomy and affect an improvement in quality of patient care.Achieving negative margins remains one of the most important determinants for local recurrence following breast conserving therapy [1]. Re-excision rates after lumpectomy for the treatment of breast cancer to achieve negative margins have been reported between 20-60% [2-5]. Re-excision lumpectomy may lead to diminished cosmetic results, delays in adjuvant therapy, and additional anxiety and expense. In order to minimize the tissue volume removed at re-excision, directed re-excision can be performed with accurate specimen orientation [6]. Directed re-excision of positive margins typically relies on the use of up to six multi-colored inks and reporting of separate margin status or widths. Traditionally, the contour of the lumpectomy specimen is oriented by the surgeon by placing stitches to mark two or more of the six sides which later allows the pathologist to reorient the specimen and ink it with six different colors to mark the anterior, posterior, medial, lateral, superior and inferior sides. Discordance between the surgeon and the pathologist in margin orientation would influence the accuracy of re-excisions. A discordance rate of 31% has recently been reported [7]. In a quality
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