Hyperspectral dark-field microscopy of human breast lumpectomy samples for tumor margin detection in breast-conserving surgery.

Significance: Hyperspectral dark-field microscopy (HSDFM) and data cube analysis algorithms demonstrate successful detection and classification of various tissue types, including carcinoma regions in human post-lumpectomy breast tissues excised during breast-conserving surgeries. Aim: We expand the application of HSDFM to the classification of tissue types and tumor subtypes in pre-histopathology human breast lumpectomy samples. Approach: Breast tissues excised during breast-conserving surgeries were imaged by the HSDFM and analyzed. The performance of the HSDFM is evaluated by comparing the backscattering intensity spectra of polystyrene microbead solutions with the Monte Carlo simulation of the experimental data. For classification algorithms, two analysis approaches, a supervised technique based on the spectral angle mapper (SAM) algorithm and an unsupervised technique based on the K-means algorithm are applied to classify various tissue types including carcinoma subtypes. In the supervised technique, the SAM algorithm with manually extracted endmembers guided by H&E annotations is used as reference spectra, allowing for segmentation maps with classified tissue types including carcinoma subtypes. Results: The manually extracted endmembers of known tissue types and their corresponding threshold spectral correlation angles for classification make a good reference library that validates endmembers computed by the unsupervised K-means algorithm. The unsupervised K-means algorithm, with no a priori information, produces abundance maps with dominant endmembers of various tissue types, including carcinoma subtypes of invasive ductal carcinoma and invasive mucinous carcinoma. The two carcinomas' unique endmembers produced by the two methods agree with each other within <2% residual error margin. Conclusions: Our report demonstrates a robust procedure for the validation of an unsupervised algorithm with the essential set of parameters based on the ground truth, histopathological information. We have demonstrated that a trained library of the histopathology-guided endmembers and associated threshold spectral correlation angles computed against well-defined reference data cubes serve such parameters. Two classification algorithms, supervised and unsupervised algorithms, are employed to identify regions with carcinoma subtypes of invasive ductal carcinoma and invasive mucinous carcinoma present in the tissues. The two carcinomas' unique endmembers used by the two methods agree to <2% residual error margin. This library of high quality and collected under an environment with no ambient background may be instrumental to develop or validate more advanced unsupervised data cube analysis algorithms, such as effective neural networks for efficient subtype classification.

No drains in reduction mammaplasty - a systematic review.

Breast reduction mammaplasty is the only effective therapeutic intervention for patients with symptomatic breast hypertrophy. In this procedure, closed suction drains have become a standard of care, while the literature supporting use of drains is lacking. In fact, with emerging data we found out that drains might not be so necessary. This review aimed to systematically compare the number of complications in drained and undrained breasts and to evaluate the safety of omitting drains in reduction mammaplasty in clinical practice. A systematic review of literature was conducted identifying all studies on drainage in reduction mammaplasty. The analysed databases revealed 13 eligible studies to be included in this review. There were 308 drained breasts and 859 undrained breasts in total in patients from 16 to 73 years of age. The resected tissue weight per side fluctuated from 108 to 1,296 grams. In total, there was only 2.4% incidence of haematoma complications in undrained breasts and 3.9% in drained breasts. Closed suction drains are still being routinely used in reduction mammaplasty, although aborting drain use is proven to be not only safe, but advantageous. The clear benefit is increased patient comfort, shortened hospital stay, decreased cost of the procedure and nurse care, and decreased rate of complications.

The influence of a previous implant-based breast reconstruction on postoperative sensation of the deep inferior epigastric artery perforator flap.

BACKGROUND: Implants and DIEP flaps have different outcomes regarding postoperative breast sensation. When compared to the preoperative healthy breast, implant-based breast reconstruction (IBBR) negatively influences postoperative breast sensation. However, it is currently unknown whether a prior IBBR also influences postoperative sensation of a replacing DIEP flap. The goal of this cohort study is to evaluate the influence of an IBBR on the postoperative sensation of a replacing DIEP flap. METHODS: Women were included if they received a DIEP flap reconstruction after mastectomy, with or without prior tissue expander (TE) and/or definitive breast implant. Sensation was measured at four intervals in 9 areas of the breast with Semmes-Weinstein monofilaments: T0 (preoperative, implant/no reconstruction), T1 (2-7 months postoperative, DIEP), T2 (± 12 months postoperative, DIEP), Tmax (maximum follow-up, DIEP). Linear mixed-effects models were used to investigate the relationship between an implant/TE prior to the DIEP flap and recovery of breast sensation. RESULTS: 142 women comprising 206 breasts were included. 48 (23.3%) breasts did, and 158 (76.7%) breasts did not have a TE/IBBR prior to their DIEP. No statistically significant or clinically relevant relationships were found between a prior implant/TE and recovery of DIEP flap breast sensation for the flap skin, native skin, or total breast skin at T1, T2, or Tmax. There were also no relationships found after adjustment for the confounders radiation therapy, BMI, diabetes, age, flap weight, follow-up, and nerve coaptation. CONCLUSIONS: An implant/TE prior to a DIEP flap does not influence the recovery of postoperative breast sensation of the DIEP flap.

Margin assessment during breast conserving surgery using diffuse reflectance spectroscopy.

Significance: During breast-conserving surgeries, it is essential to evaluate the resection margins (edges of breast specimen) to determine whether the tumor has been removed completely. In current surgical practice, there are no methods available to aid in accurate real-time margin evaluation. Aim: In this study, we investigated the diagnostic accuracy of diffuse reflectance spectroscopy (DRS) combined with tissue classification models in discriminating tumorous tissue from healthy tissue up to 2 mm in depth on the actual resection margin of in vivo breast tissue. Approach: We collected an extensive dataset of DRS measurements on ex vivo breast tissue and in vivo breast tissue, which we used to develop different classification models for tissue classification. Next, these models were used in vivo to evaluate the performance of DRS for tissue discrimination during breast conserving surgery. We investigated which training strategy yielded optimum results for the classification model with the highest performance. Results: We achieved a Matthews correlation coefficient of 0.76, a sensitivity of 96.7% (95% CI 95.6% to 98.2%), a specificity of 90.6% (95% CI 86.3% to 97.9%) and an area under the curve of 0.98 by training the optimum model on a combination of ex vivo and in vivo DRS data. Conclusions: DRS allows real-time margin assessment with a high sensitivity and specificity during breast-conserving surgeries.

A Scoping Review of Innervated Breast Reconstruction.

BACKGROUND: After breast surgery, patients experience significant alterations to breast sensation, which can diminish quality of life. Nerve coaptation technique, introduced in the 1990s, has gained traction in recent years. We performed a scoping review of the literature to determine the available outcomes in sensate breast reconstruction. METHODS: The review was conducted using Preferred Reporting Items for Systematic Reviews and Meta-Analyses Extension for Scoping Reviews statement guidelines. EMBASE and PubMed databases were queried using standardized terminology. Studies were included if they reported original sensory outcomes following innervation techniques during breast reconstruction and were published from January 1, 1990, to April 18, 2022. Data extraction and analyses were performed on Microsoft Excel. RESULTS: From 602 screened articles, 27 studies met the inclusion criteria. Innervated autologous reconstructive procedures were described in 24, whereas the remaining 3 (all published after 2019) described direct reinnervation of the nipple-areola complex. Most (88.9%) of the studies comparing innervated versus noninnervated reconstruction reported improved sensory outcomes in at least 1 modality. Two studies investigated patient-reported outcomes using validated questionnaires, both of which reported improvement with innervated reconstruction. CONCLUSIONS: Sensate breast reconstruction has the potential to improve outcomes for patients. There is a recent progressive increase in studies involving direct nipple-areolar reinnervation. Larger, prospective studies are needed to better characterize the quality-of-life outcome using validated scales, as well as evaluate sensory and patient-reported outcomes with implant and autologous reconstruction.

Intraoperative Evaluation of Breast Tissues During Breast Cancer Operations Using the MasSpec Pen.

Importance: Surgery with complete tumor resection remains the main treatment option for patients with breast cancer. Yet, current technologies are limited in providing accurate assessment of breast tissue in vivo, warranting development of new technologies for surgical guidance. Objective: To evaluate the performance of the MasSpec Pen for accurate intraoperative assessment of breast tissues and surgical margins based on metabolic and lipid information. Design, Setting, and Participants: In this diagnostic study conducted between February 23, 2017, and August 19, 2021, the mass spectrometry-based device was used to analyze healthy breast and invasive ductal carcinoma (IDC) banked tissue samples from adult patients undergoing breast surgery for ductal carcinomas or nonmalignant conditions. Fresh-frozen tissue samples and touch imprints were analyzed in a laboratory. Intraoperative in vivo and ex vivo breast tissue analyses were performed by surgical staff in operating rooms (ORs) within 2 different hospitals at the Texas Medical Center. Molecular data were used to build statistical classifiers. Main Outcomes and Measures: Prediction results of tissue analyses from classification models were compared with gross assessment, frozen section analysis, and/or final postoperative pathology to assess accuracy. Results: All data acquired from the 143 banked tissue samples, including 79 healthy breast and 64 IDC tissues, were included in the statistical analysis. Data presented rich molecular profiles of healthy and IDC banked tissue samples, with significant changes in relative abundances observed for several metabolic species. Statistical classifiers yielded accuracies of 95.6%, 95.5%, and 90.6% for training, validation, and independent test sets, respectively. A total of 25 participants enrolled in the clinical, intraoperative study; all were female, and the median age was 58 years (IQR, 44-66 years). Intraoperative testing of the technology was successfully performed by surgical staff during 25 breast operations. Of 273 intraoperative analyses performed during 25 surgical cases, 147 analyses from 22 cases were subjected to statistical classification. Testing of the classifiers on 147 intraoperative mass spectra yielded 95.9% agreement with postoperative pathology results. Conclusions and Relevance: The findings of this diagnostic study suggest that the mass spectrometry-based system could be clinically valuable to surgeons and patients by enabling fast molecular-based intraoperative assessment of in vivo and ex vivo breast tissue samples and surgical margins.

Symptomatic Calcifications after Mastectomy: A Rare Case Report with a Review of the Literature.

Introduction: Symptomatic calcifications of the breast or skin after breast cancer surgery and adjuvant radiotherapy are a rare entity, with only a few case reports published worldwide, reducing the patient's quality of life, whilst asymptomatic calcifications are a common finding on imaging methods. Case presentation: Herein, we present a rare case report of calcifications after mastectomy and post-mastectomy radiation therapy causing chronic inflammation with ulceration and fistula formation, with a two-step surgical approach consisting of excision with linear suture and excision with the reconstruction using a thoraco-epigastric flap. Conclusions: To our knowledge, this is the first publication proving the feasibility of this therapy in patients with symptomatic dystrophic calcifications of the skin or the breast. Moreover, the article provides an up-to-date review of published studies about symptomatic calcifications after breast cancer surgery and radiotherapy with a focus on the time of the clinical manifestation from the radiotherapy and the used radiotherapy scheme.

Adipose perforator flaps without skin donor site: "in between" single scar approach for reconstruction of small peripheral breast defects after lumpectomy.

In breast conserving surgery, the reconstruction of defects in small breasts where volume displacement techniques are not feasible can be challenging. In contrast, patients with bigger breasts may not wish to undergo major breast remodeling surgery or breast symmetrization procedures. In such cases, volume replacement techniques can be beneficial, but these leave additional scars and are time consuming. The authors propose an "in between" single scar approach to perform both lumpectomy and reconstruction of small peripheral breast tumors. This approach reduces morbidity and operating time compared with standard volume replacement techniques. The tumors are resected from below, guided by wire, using an incision in the lateral breast crease or inframammary fold, depending on their location. The same incision is used to raise an adipose or adipofascial flap based on perimammary perforators, lateral thoracic artery perforator flap (LTAP), lateral intercostal artery perforator flap (LICAP), or anterior intercostal artery perforator flaps (AICAP) flaps, without skin donor site. Between March and November 2022, eight patients underwent this procedure. In four cases LICAP flap was used; in three-AICAP flap was chosen; and in one-LTAP perforator flap was used. Clear surgical margins were achieved in all cases. The average follow-up time was 9.9 months, during which no local recurrences were detected. All flaps survived. Two patients experienced seromas at the donor site, and an organized hematoma was also reported. This approach represents a viable alternative to volume displacement techniques or no reconstruction for small peripheral lumpectomy defects.

Development and Validation of a Diagnostic Histopathological Scoring System for Capsular Contracture Based on 720 Breast Implant Capsules.

BACKGROUND: Capsular contracture is traditionally evaluated with the Baker classification, but this has notable limitations regarding reproducibility and objectivity. OBJECTIVES: The aim of this study was to develop and validate procedure-specific histopathological scoring systems to assess capsular contracture severity. METHODS: Biopsies of breast implant capsules were used to develop histopathological scoring systems for patients following breast augmentation and breast reconstruction. Ten histological parameters were evaluated by multivariable logistic regression to identify those most associated with capsular contracture. Significant parameters (P < .05) were selected for the scoring systems and assigned weighted scores (1-10). Validation was assessed from the area under the curve (AUC) and the mean absolute error (MAE). RESULTS: A total of 720 biopsies from 542 patients were included. Four parameters were selected for the augmentation scoring system, namely, collagen layer thickness, fiber organization, inflammatory infiltration, and calcification, providing a combined maximum score of 26. The AUC and MAE for the augmentation scoring system were 81% and 0.8%, which is considered strong. Three parameters were selected for the reconstruction scoring system, namely, fiber organization, collagen layer cellularity, and inflammatory infiltration, providing a combined maximum score of 19. The AUC and MAE of the reconstruction scoring system were 72% and 7.1%, which is considered good. CONCLUSIONS: The new histopathological scoring systems provide an objective, reproducible, and accurate assessment of capsular contracture severity. We propose these novel scoring systems as a valuable tool for confirming capsular contracture diagnosis in the clinical setting, for research, and for implant manufacturers and insurance providers in need of a confirmed capsular contracture diagnosis.

Abdominal donor-site complications following autologous breast reconstruction: A multi-institutional multisurgeon study.

BACKGROUND: The deep inferior epigastric perforator (DIEP) free flap is the gold standard procedure for autologous breast reconstruction. Although breast-related complications have been well described, donor-site complications and contributing patient risk factors are poorly understood. METHODS: We examined a multi-institutional, prospectively maintained database of patients undergoing DIEP free flap breast reconstruction between 2015 and 2020. We evaluated patient demographics, operative details, and abdominal donor-site complications. Logistic regression modeling was used to predict donor-site outcomes based on patient characteristics. RESULTS: A total of 661 patients were identified who underwent DIEP free flap breast reconstruction across multiple institutions. Using logistic regression modeling, we found that body mass index (BMI) was an independent risk factor for umbilical complications (odds ratio [OR] 1.11, confidence interval [CI] 1.04-1.18, p = 0.001), seroma (OR 1.07, CI 1.01-1.13, p = 0.003), wound dehiscence (OR 1.10, CI 1.06-1.15, p = 0.001), and surgical site infection (OR 1.10, CI 1.05-1.15, p = 0.001) following DIEP free flap breast reconstruction. Further, immediate reconstruction decreases the risk of abdominal bulge formation (OR 0.22, CI 0.108-0.429, p = 0.001). Perforator selection was not associated with abdominal morbidity in our study population. CONCLUSIONS: Higher BMI is associated with increased abdominal donor-site complications following DIEP free flap breast reconstruction. Efforts to lower preoperative BMI may help decrease donor-site complications.

Mammoplasty Using Modified Superomedial Pedicle Technique in Severely Macromastia and Ptotic Breasts.

Mammoplasty is a surgery commonly used for macromastia. Many mammoplasty techniques are described, all with their specific pros and cons. However, the concern to avoid serious complications sometimes takes precedence, and the ideal result cannot be. For macromastia and severely ptotic breasts, usually the free nipple-areolar complex (NAC) mammoplasty technique is implemented. The results, however, may only be completely satisfactory regarding cosmetics. Loss of NAC, poor appearance, flabbiness, flattening, and ptosis are among the disadvantages of this technique. This study aimed to present the results of mammoplasty employing the superomedial pedicle technique without interrupting a macromastia central base with a pedicle length of 8 to 18 cm. According to the literature, many plastic surgeons recommend the free NAC rather than the pedicle technique because of the high complication rates in mammoplasties planned for highly ptotic breasts and macromastia. On the other hand, many free NAC techniques and their modifications with pedicle mammoplasty are described. The general conviction is that a standard method, protocol, or technique good for all patients does not exist. Our results are more acceptable both cosmetically and physiologically. Therefore, the superomedial pedicle technique can be modified to achieve ideal results where free NAC mammoplasty is considered for severe macromastia and ptotic patients. This combined method contributes to the viability of NAC by increasing blood supply to breast tissue and providing an ideal breast appearance.

The FALD-V: A predictive formula for preoperative volume assessment of adipose tissue transplantation in FALD flap.

BACKGROUND: The fat-augmented latissimus dorsi (FALD) flap is an evolution of the traditional latissimus dorsi (LD) flap, which allows to obtain a total autologous breast reconstruction (BR) avoiding the use of breast implants. The aim of this study was to develop a predictive preoperative formula in order to estimate and optimize the amount of fat to be transferred during FALD flap BR, using only anthropometric measurements. METHODS: We conducted a prospective clinical study between September 2020 and April 2023. All patients underwent back pre-operative ultrasound scan to assess the subcutaneous skin paddle thickness (SPT) and a regression analysis was performed to evaluate which anthropometric variable had a better correlation with this thickness. RESULTS: Data from 66 FALD flaps were collected. The mean SPT was 11.95 mm (SD 4.56). A significant correlation between SPT and body mass index (BMI) was found (r = 0.640, p < 0.0001). Using the fat-to-capacity ratio (113%), the following formula (the FALD-V) was developed to predict the needed fat transfer into FALD flap: [-509 + 12.32 × BMI + 11.71 × skin paddle width + 17.43 × skin paddle height] × 1.13. The considered variables (BMI, skin paddle width and skin paddle height) were statistically significant (p < 0.001, p = 0.0483, p = 0.0154, respectively). The cross-validation confirmed the accuracy of the formula (r = 0.810). CONCLUSION: The FALD-V can be used as an innovative complimentary device in the planning of FALD flap one-stage total autologous BR. To enhance its application, a 3.0 WebApp at www.braflap.com (and www.breast-v.com) is available free of charge for both iOS and Android devices. LEVEL OF EVIDENCE: II.

[Emphasizing the homogenization of mastoscopy].

As a major development in breast surgery, mastoscopy has been proven safe and been involved in almost all breast surgery operative procedures. Its extensive development has cultivated a group of positively young and middle-aged academic backbones, at the same time nurtured high-level breast subject leaders, providing innovative ideas and useful reference for the high-quality development of breast specialty. However, due to the relatively weak breast specialty, uneven technical treatment ideas, insufficient promotion of endoscopic technology, unique learning curve, and inhomogeneous technical aspects, the development of mastoscopy technology is uneven and the level of homogenization is low. It should be started from four aspects, including strategic focus, treatment idea, endoscopic technical training, and mastoscopic operation. Multiple measures should be taken to comprehensively improve the homogenization of mastoscopic level.

Impact of autologous breast reconstruction on bra fit.

PURPOSE: To inform bra design by analyzing 3D surface images of breast cancer patients who underwent autologous breast reconstruction. METHODS: We computed bra design measurements on 3D surface images of patients who underwent unilateral and bilateral autologous breast reconstruction. Breast measurements and right-left symmetry between preoperative baseline and postoperative time points were compared using either paired Student t-test or Wilcoxon signed-rank test, depending on the data's distribution. Regression analysis determined associations between measurements and patient characteristics such as age. Postoperative measurements and symmetry differences were also compared between autologous and implant-based breast reconstruction. RESULTS: Among participants who underwent bilateral autologous breast reconstruction, the reconstructed breasts were smaller and positioned higher on the chest wall than their native breasts. For patients who underwent unilateral reconstruction, similar postoperative changes were observed in the contralateral breast due to symmetry procedures. Overall, for participants whose baseline breast measurements showed substantial asymmetry, unilateral reconstruction decreased right-left asymmetry whereas bilateral reconstruction amplified right-left asymmetry. Preoperative baseline breast measurements, age, and BMI were statistically significantly associated with most postoperative breast measurements for participants who underwent bilateral autologous reconstruction. Compared to implant-based reconstruction, autologous reconstruction resulted in fewer changes in breast shape and symmetry that are pertinent to bra fit. CONCLUSION: Preoperative baseline breast measurements, age, and BMI can impact bra designs for breast cancer survivors who undergo autologous reconstruction due to size, shape, and symmetry changes. Bra needs of people who undergo autologous reconstruction differ from those who undergo implant-based reconstruction.

Effectiveness and toxicity of five-fraction prone accelerated partial breast irradiation.

PURPOSE: Our institution was an early adopter of 5-fraction accelerated partial breast irradiation (ABPI) to treat women with early-stage breast cancer. This study reports long-term oncologic and cosmetic outcomes. METHODS: We included patients receiving APBI 600 cGy × 5 fx delivered every other day or every day between 2010 and 2022. Logistic regression models were used to identify factors associated with development of late toxicities, clinician, and patient-rated cosmesis. Kaplan-Meier methodology was used to calculate overall survival (OS), disease-free survival (DFS), and locoregional recurrence-free survival (LR-RFS). RESULTS: 442 patients received APBI either daily (56%) or every other day (44%) in the prone position (92%). At a median follow-up of 48 months (range: 5.96-155 months), 12 (2.7%) patients developed a local recurrence (LR). Out of 258 patients with > 3-month toxicity data available, the most common late grade ≥ 2 adverse event was breast fibrosis (6.2%). On multivariate analysis, daily APBI treatment (vs every other day) did not correlate with an increased risk of any late grade ≥ 2 toxicity though it did correlate with a lower risk of any late grade ≥ 2 fibrosis. Overall, at a median follow-up of 80 months, the rates of good-excellent physician and patient-rated cosmesis were 95% and 85%, respectively, with no difference between patients treated on consecutive vs. every other day. On multivariate analysis, patients who did not receive any adjuvant therapy were at increased risk of developing a LR. Five-year OS, LRFS, and DFS were 97.2%, 97.7%, and 89.5%, respectively. CONCLUSIONS: Five-fraction APBI delivered primarily in the prone position either daily or every other day was effective with low rates of local recurrence, minimal toxicity, and excellent cosmesis at long-term follow-up.

Surgical safety and effectiveness of bilateral axillo-breast approach robotic thyroidectomy: a systematic review and meta-analysis.

OBJECTIVES: To assess the safety and effectiveness of bilateral axillo-breast approach robotic thyroidectomy in thyroid tumor. METHODS: Bilateral axillo-breast approach robotic thyroidectomy and other approaches (open thyroidectomy, transoral robotic thyroidectomy, and bilateral axillo-breast approach endoscopic thyroidectomy) were compared in studies from 6 databases. RESULTS: Twenty-two studies (8830 individuals) were included. Bilateral axillo-breast approach robotic thyroidectomy had longer operation time, greater cosmetic satisfaction, and reduced transient hypoparathyroidism than conventional open thyroidectomy. Compared to bilateral axillo-breast approach endoscopic thyroidectomy, bilateral axillo-breast approach robotic thyroidectomy had greater amount of drainage, lower chances of transient vocal cord palsy and permanent hypothyroidism, and better surgical completeness (postopertive thyroblobulin level and lymph node removal). Bilateral axillo-breast approach robotic thyroidectomy induced greater postoperative drainage and greater patient dissatisfaction than transoral robotic thyroidectomy. CONCLUSION: Bilateral axillo-breast approach robotic thyroidectomy is inferior to transoral robotic thyroidectomy in drainage and cosmetic satisfaction but superior to bilateral axillo-breast approach endoscopic thyroidectomy in surgical performance. Its operation time is longer, but its cosmetic satisfaction is higher than open thyroidectomy.

Rates of breast reconstruction uptake and attitudes toward breast cancer and survivorship among south asians: A literature review.

Our aim in this review was to ascertain rates of breast reconstruction among South Asian patients and identify attitudes towards breast cancer, survivorship, and breast reconstruction. Mastectomy rates for South Asian patients ranged from 52% to 77% and reconstruction following mastectomy varied from 0% to 14%. A negative perception of cancer, fears of social isolation, and taboos around breasts can prevent South Asian women from receiving surgical care after a breast cancer diagnosis.

Cross-Correlation of Confocal Images for Excised Breast Tissues of Total Mastectomy.

OBJECT: The purpose of this study is to develop an image artifact removal method for radar-based microwave breast imaging and demonstrates the detectability on excised breast tissues of total mastectomy. METHODS: A cross-correlation method was proposed and measurements were conducted. A hand-held radar-based breast cancer detector was utilized to measure a breast at different orientations. Images were generated by multiplying the confocal image data from two scans after cross-correlation. The optimum reconstruction permittivity values were extracted by the local maxima of the confocal image intensity as a function of reconstruction permittivity. RESULTS: With the proposed cross-correlation method, the contrast of the imaging result was enhanced and the clutters were removed. The proposed method was applied to 50 cases of excised breast tissues and the detection sensitivity of 72% was achieved. With the limited number of samples, the dependency of detection sensitivity on the breast size, breast density, and tumor size were examined. CONCLUSION AND SIGNIFICANCE: The detection sensitivity was strongly influenced by the breast density. The sensitivity was high for fatty breasts, whereas the sensitivity was low for heterogeneously dense breasts. In addition, it was observed that the sensitivity was high for extremely dense breast. This is the first detailed report on the excised breast tissues.