Clinical significance of S100A7 protein in predicting recurrence of breast cancer in patients undergoing breast-conserving surgery with radiotherapy

Objective To investigate the relationship between the expression of S100A7 protein and prediction of recurrence and prognosis of breast cancer in patients undergoing breast-conserving surgery combined with radiotherapy.Methods 349 samples of carcinoma tissue wax blocks were selected from January 2011 to January 2014 in Qingdao Central Hospital.All the patients had undergone breast-conserving surgery.We analyzed S100A7 expression in tumor tissue by immunohistochemical staining.Using univariate and multivariate analyses,we evaluated the relationship between S100A7 and clinical results,to explore independent risk factors for local regional recurrence(LRR).Results The positive expression of S100A7 in the recurrence group(66.7%)was significantly higher than in the non-recurrence group(38.4%),P=0.025.A log-rank test showed that high S100A7 expression was significantly correlated with 5-year regional recurrence free survival rate(RFS)(94.9%vs 89.5%,P=0.0408),distant metastasis free survival rate(DFS)(95.4%vs 83.5%,P<0.001),and overall survival rate(OS)(99.0%vs 92.5%,P=0.0011).Histological grade,vessel carcinoma embolus,lymph node metastasis,S100A7 expression,and tumor size were factors that influenced RFS.Multivariate analysis of the Cox proportional hazard model showed that high S100A7 expression was an independent risk factor that affected breast cancer RFS(HR=6.864,95%CI:1.575-29.915,P=0.01).Thus,we concluded that high S100A7 expression is associated with increased risk of LRR and distant metastasis of breast cancer after breast-conserving surgery and postoperative radiotherapy.S100A7 can be used as a molecular marker to screen for patients with high recurrence risk after breast-conserving surgery.

The 10-Year Local Recurrence and Partial Breast Radiotherapy for Early Breast Cancer Treated by Conservative Surgery

To study the local recurrence and the role of whole breast radiotherapy for early breast cancer treated by conservative surgery. METHODS From April 1990 to December 2000, 49 patients with early primary breast cancer were treated by conservative surgery in our hospital. The cases were comprised of Stage 0, 1; Stage Ⅰ, 31; and Stage Ⅱa, 17. Forty cases underwent quadrantectomy plus axillary lymph node dissection, and the other 9 cases had lumpectomy alone. Irradiation, which was received by 39 patients, was administered by using low tangential half fields with 6 MV X-ray to decrease the pulmonary irradiative volume. The dose to the whole breast was 45 Gy/22 ～23f/4.5W, then a 15 Gy boost dose was delivered to the tumor bed by an electron beam. The other patients underwent an irradiated regional field according to postoperative pathology. RESULTS All patients were followed-up for 10 years or more. The 10- year local recurrence rates, distant metastasis rates and survival rates were 6.1%, 4.1% and 98.0% respectively. All of the 3 patients who had a local recurrence had infiltrative carcinomas and negative lymph nodes. The 10-year local recurrence rate was higher （2.6% vs. 20.0%） with nonpostoperative whole breast radootherapy, but the statistical difference was not marked because of the low number of cases. All of the recurrent lesions localized within 3 cm of the primary lesion. CONCLUSION Original recurrence of the tumor was the main type of local recurrence. Radiotherapy after conservative surgery is very essential. After conservative surgery it is feasible that irradiation can be delivered alone to the neighboring region of the tumor bed. Partial breast radiotherapy can substitute for whole breast radiotherapy.

The Effectiveness of Intraoperative Frozen Section Analysis of Safety Margins in Breast Conserving Surgery and the Role of Surgeon in Decreasing the Rate of Positive Margins

Introduction: Nowadays the more accepted surgical option for treating early breast cancer is breast conserving surgery. The main challenge in this type of surgery is to get free safety margins without need of second surgical operation, so many breast surgeons have started to depend on intraoperative frozen sections to ensure free safety margins. Aim of work: To assess our policy that we prefer to depend on intraoperative frozen section analysis to get free safety margin in breast conserving surgery from the 1st surgery, and its oncologic outcome. Patients and Methods: This is a retrospective study conducted in Oncology Center—Mansoura University (OCMU), where the data of 219 patients with breast cancer, who were managed by breast conserving surgery with intraoperative frozen section analysis of the safety margins, was analyzed. Results: The intraoperative frozen section analysis of safety margin was negative from the start in 183 (83.6%) patients, while it was positive in 36 patients (16.4%). Intraoperative decision of margin re-excision was applied for 29 patients (13.2%) in order to reach negative margin, modified radical mastectomy was offered for 4 patients (1.8%), while nipple sparing mastectomy with immediate breast reconstruction using latissimus dorsi flap was offered for 3 patients (1.4%). The postoperative paraffin results were typical with intraoperative frozen section analysis results in 216 patients (98.6%) and different results were obtained in only 3 patients (1.4%) who were managed by modified radical mastectomy in a second operation. Only 4 patients had local recurrence (1.8%) during the period of follow-up duration which was ranged from 1 to 86 months with mean ± SD (22.3 ± 14.1). Conclusion: The intraoperative frozen section analysis of safety margins in breast conserving surgery has very high-rate typical results with the paraffin section analysis and it is very helpful in decreasing the rate of second surgical operation in cases of infiltrated margins. It should be used routinely in all cases of breast conserving surgery.

Breast Conserving Surgery and Sentinel Lymph Node Biopsy under Local Anesthesia for Breast Cancer

Background: Breast conserving surgery and sentinel lymph node biopsy has become the standard operation for early breast cancer. This operation has been performed under local anesthesia for patients that would like short-term admission or for those not indicated for general anesthesia due to complications. This report presents the outcomes of breast conserving surgery and sentinel lymph node biopsy under local anesthesia. Patients and Methods: The study included 61 patients with breast cancer that were all definitely diagnosed before surgery. The indications were preoperatively diagnosed localized DCIS, invasive carcinoma measuring less than 3 cm in tumor diameter on ultrasound, and tumors with negative axillary lymph nodes. The surgical procedures included breast conserving surgery associated with sentinel lymph node navigation biopsy. Results: The surgery could be performed under local anesthesia in all 61 patients, and no patient was converted to general anesthesia. Four patients had sentinel lymph node metastasis. Surgical stumps were positive in 18 patients (29.5%). Ten Gy of boost irradiation of the tumor bed was added to the conventional breast irradiation for these patients. There were no serious complications associated with surgery. Conclusion: Breast conserving surgery and sentinel lymph node biopsy for early breast cancer can be performed safely under local anesthesia. This procedure contributes to shortening the length of hospitalization and thereby saving medical resources without deceasing the quality of treatment.

Versatility of therapeutic reduction mammoplasty in oncoplastic breast conserving surgery

Oncoplastic breast conserving surgery is the gold standard approach for the surgical treatment of early breast cancer. There is a well defined technique named "therapeutic mammoplasty" which is characterized for using a reduction mammaplasty technique to treat breast cancer conservatively. In our current practice, "therapeutic mammoplasty" or therapeutic reduction mammaplasty is our favorite oncoplastic breast conserving approach which it used in almost half of our patients. This technique is very versatile allows us the resection of tumors located in all breast quadrants of patients with moderate-to large-sized breasts. We describe a series of 57 patients who were treated using a therapeutic reduction mammaplasty. All surgical procedures were carried out by one comprehensive breast surgeon who planned and designed the surgery performing both oncologic and reconstructive procedures. Surgical margins were insufficient in eight patients(14%). Nine patients(15.8%) had a complication in early postoperative period and in one of them adjuvant radiotherapy was delayed four months due to a wound dehiscence. The rate of synchronous contralateral symmetrization was 31.6%. Our conclusion is that reduction mammaplasty is a useful and safe skill to treat breast cancer conservatively playing a very important role therefore it must be situated in the priority of learning objectives.

Breast Conserving Surgery: Has the Standard of Care Enhanced Outcomes for Patients?

Breast Conserving Surgery (BCS) is a rapidly emerging field increasingly adopted to facilitate breast conservation and preserve breast aesthetics. Since the publication of the Randomized Controlled Trials (RCTs) of Breast Conserving Surgery versus mastectomy in early breast cancer, the adoption of BCS for breast cancer patients’ surgical management has been comprehensive. A computerized bibliographic search was performed on PubMed/MEDLINE, Embase, Google Scholar and Cochrane library databases. This article aims to perform a thorough review of new data regarding invasive cancer and margins while evaluating patient outcomes related to BCS after neoadjuvant chemotherapy focusing on margins, imaging evaluation, the extent of resection, and local regional recurrence outcomes. The growth pattern and biopsy of Ductal Carcinoma In Situ (DCIS) differ from invasive cancer, impacting margins. It is essential to understand how the Society of Surgical Oncology (SSO) DCIS margin guideline has influenced practice. Early breast cancer surgical management should be unique to each patient, driven by evidence-based medicine, and focused on specific clinical, histological, and molecular characteristics of the tumor. Conclusion: The current management for early breast cancer should be tailored and evidence-based to each patient based on the clinical, histological and molecular characteristics of the tumor. Presumably, the standard of care in BCS has enhanced the outcomes for this patient population. This review made by peers will help surgeons to stay up to date with the current literature and help them manage breast cancer while improving multiple clinical parameters such as Disease-Free Survival (DFS), Recurrence-Free Survival (RFS) and most importantly Overall Survival (OS).

Is breast conservative surgery a reasonable option in multifocal or multicentric tumors?

The incidence of multifocal(MF) and multicentric(MC) carcinomas varies widely among clinical studies,depending on definitions and methods for pathological sampling.Magnetic resonance imaging is increasingly used because it can help identify additional and conventionally occult tumors with high sensitivity.However,false positive lesions might incorrectly influence treatment decisions.Therefore,preoperative biopsies must be performed to avoid unnecessary surgery.Most studies have shown higher lymph node involvement rates in MF/MC tumors than in unifocal tumors.However,the rate of local recurrences is usually low after breast conservative treatment(BCT) of MC/MF tumors.It has been suggested that BCT is a reasonable option for MC/MF tumors in women aged 50-69 years,with small tumors and absence of extensive ductal carcinoma in situ.A metaanalysis showed an apparent decreased overall survival in MC/MF tumors but data are controversial.Surgery should achieve both acceptable cosmetic results and negative margins,which requires thorough preoperative radiological workup and localization of lesions.Boost radiotherapy techniques must be evaluated since double boosts might result in increased toxicity,namely fibrosis.In conclusion,BCT is feasible in selected patients with MC/MF but the choice of surgery must be discussed in a multidisciplinary team comprising at least radiologists,surgeons and radiotherapists.

Parallel pathways:A chronicle of evolution in rectal and breast cancer surgery

In this editorial,we have analyzed the historical evolution of rectal and breast cancer surgery,focusing on the progressive reduction of demolitive approaches and the increasing use of more conservative strategies,accompanied by a growing emphasis on perioperative treatments aimed at enhancing surgical outcomes.All of these changes have been made possible due to an increased awareness and understanding of oncological diseases and improved perioperative treatments.

Magnetic resonance imaging findings of radiation-induced breast angiosarcoma:A case report

BACKGROUND Breast conservation surgery(BCS)with adjuvant radiotherapy has become a gold standard in the treatment of early-stage breast cancer,significantly reducing the risk of tumor recurrence.However,this treatment is associated with adverse effects,including the rare but aggressive radiation-induced angiosarcoma(RIAS).Despite its rarity and nonspecific initial presentation,RIAS presents a challenging diagnosis,emphasizing the importance of imaging techniques for early detection and accurate diagnosis.CASE SUMMARY We present a case of a 48-year-old post-menopausal woman who developed skin ecchymosis on the right breast seven years after receiving BCS and adjuvant radiotherapy for breast cancer.Initial mammography and ultrasound were inconclusive,showing post-treatment changes but failing to identify the underlying angiosarcoma.Contrast-enhanced breast magnetic resonance imaging(MRI)revealed diffuse skin thickening and nodularity with distinctive enhan-cement kinetics,leading to the diagnosis of RIAS.This case highlights the crucial role of MRI in diagnosing and determining the extent of RIAS,facilitating timely and appropriate surgical intervention.CONCLUSION Breast MRI is crucial for detecting RIAS,especially when mammography and ultrasound are inconclusive.

Imaging of the treated breast post breast conservation surgery/oncoplasty: Pictorial review

Mammographic appearance of the normal breast is altered in the post-operative setting. It is essential to be aware of the normal findings as well as to identify features of recurrent disease with particular emphasis on radiologicalpathological concordance. Digital breast tomosynthesis and volumetric breast density add incremental value in this clinical setting. We present a pictorial review of various cases to illustrate normal post-operative findings as well as mammographic features suspicious for recurrent disease.

Significance of ipsilateral breast tumor recurrence after breast conserving treatment: role of surgical removal

Objective： To analyze the pattern over time （dynamics） of further recurrence and death after ipsilateral breast tumor recurrence （IBTR） in breast cancer patients undergoing breast conserving treatment （BCT）. Methods： A total of 338 evaluable patients experiencing IBTR were extracted from a database of 3,293 patients undergoing BCT. The hazard rates for recurrence and mortality throughout 10 years of follow-up after IBTR were assessed and were compared to the analogous estimates associated to the primary treatment. Results： In a time frame with the time origin at the surgical treatment for IBTR, the hazard rate for further recurrence displays a bimodal pattern （peaks at the second and at the sixth year）. Patients receiving mastectomy for IBTR reveal recurrence and mortality dynamics similar to that of node positive （N＋） patients receiving mastectomy as primary surgery, apart from the first two-three years, when IBTR patients do worse. If the patients with time to IBTR longer than 2.5 years are considered, differences disappear. Conclusions： The recurrence and mortality dynamics following IBTR surgical removal is similar to the corresponding dynamics following primary tumor removal. In particular, patients with time to IBTR in excess of 2.5 years behave like N＋ patients following primary tumor removal. Findings may be suitably explained by assuming that the surgical manoeuvre required by IBTR treatment is able to activate a sudden growing phase for tumor foci most of which, as suggested by the systemic model of breast cancer, would have reached the clinical level according to their own dynamics.

Toxicity of Hypofractionated Radiotherapy Following Breast Conservative Surgery in Breast Cancer

Background:Adjuvant radiotherapy has increased disease-free and overall survival rates in breast cancer. Conventionally fractionated radiotherapy delivers 50 Gy over 5 weeks which is the standard approach. A shorter duration of hypofractionated radiotherapy (HFRT) will be more convenient for patients and treatment providers if found safe and equally effective. Material and Methods: Fifty-four breast cancer patients who underwent breast conservative surgery (BCS) were enrolled in this study. The patients received 4005 cGy/15 fractions. A boost to the tumor bed was administered in all patients. In this study, radiotherapy induced toxicity was evaluated. Results: In this study, the median age of our patients was 48 years with age ranged from 28 to 69 years. Acute skin toxicity was assessed, and it was noted that grade 2 skin toxicity was shown in only 6 patients (11.1%) at the end of radiotherapy and disappeared after 6 weeks of treatment. Late skin toxicity (telangectasia, hyperpigmentation, and subcutaneous fibrosis) was assessed and showed that most patients had grade 0 toxicity with no grade 3 toxicity at all. Regarding pulmonary toxicity, 5 patients (9.3%) developed acute pneumonitis and as regards chronic lung toxicity, it was evident in only 3 patients, 2 patients (3.7%) were grade 1 and 1 patient (1.9%) was grade 2. Cardiac toxicity was evident in 2 patients (7.1%) of the left breast cancer patients. Regarding lymphoedema, most patients that showed lymphoedema were grade 1. Conclusion: The results confirm the safety and feasibility of adjuvant hypofractionated whole breast radiotherapy in breast cancer patients in terms of acute and late toxicity.

Preliminary analysis of a clinical trial for three-dimensional conformal radiation therapy after conservative surgery

Objective The aim of this study was to evaluate the efficacy, complications and cosmetic results of three-dimensional conformal radiation therapy for early breast cancer after conservative surgery.

Concomitant Boost Radiotherapy after Conservative Breast Surgery in Early Breast Cancer

Background: Radiation therapy after breast conserving surgery is a standard part of treatment for invasive breast cancer. Based on radiobiological models, it was found that shorter radiation schedules offered the promise of equivalent local control to standard radiation therapy by giving larger doses per fraction in shorter period of time. Methods: This study included 36 female patients with operable invasive stage I-II breast cancer. These patients underwent microscopic wide local excision of the primary tumor and lymph node dissection. They received adjuvant radiotherapy. The radiation dose was 40 Gy total dose in 15 fractions for whole breast and additional dose of 9 Gy in three consecutive fractions was delivered to tumour cavity simultaneously. Results: Mean age was 52 years (range: 30 - 67);most patients were of stage II disease and Grade II was the most common one. Invasive ductal carcinoma was reported in 94.4% and 72.2% of patients were hormone receptor positive. After median follow-up of 52 months, all patients were alive and ipsilateral local recurrence was reported in 1 case only. Grade IV radiation toxicity was not observed;moist desquamation was the most common acute reaction (61%) with grade III in 5.5% followed by dry desquamation in 55.6% of grade I only. Grade I erythema was recorded in 41.7% and grade II in 11%. Fibrosis was the most frequent late reaction (44.3%) with grade II in 11% followed by telengectesia then pigmentation (41.7%, 33.3% respectively). Conclusion: The regimen used in this study appears promising with acceptable acute toxicities and convenient for our patients and has the advantage of economic use of radiation facilities. However, larger number of patients and longer period of follow-up are needed for further evaluation.

Oncoplastic Breast Surgery Using Spindle Shaped-Partial Mastectomy for Early Breast Cancer in the Upper Quadrant Area

Background: Oncoplastic surgery is becoming more common, however, only several reports have been published in Japan. We report the results of simple oncoplastic surgery for Japanese patients with early breast cancer in the upper quadrant area. Methods: In seven patients with a past history of breast-feeding and ptotic breasts, we performed oncoplastic surgery involving partial mastectomy and the resection of excess skin and parenchymal tissue. Results: None of the patients received a contralateral operation to produce symmetrical breasts. The width of the resected excess skin tissue ranged from 20 to 50 mm, with the mean width being 30 mm, and its length ranged from 50 to 90, with the mean length being 77 mm. The width of the resected gland tissue ranged from 40 to 65 mm, with the mean width being 53 mm, and its length ranged from 70 to 100 mm, with the mean length being 97 mm. The cosmetic results were excellent. Conclusions: Oncoplastic surgery using spindle shaped-resection was successfully performed in patients with upper quadrant lesions, and the cosmetic results were excellent.

Correlation of radiotherapy with prognosis of elderly patients with hormone receptor-positive breast cancer according to immunohistochemical subtyping

Objective: The present study examined the effect of radiotherapy on recurrence and survival in elderly patients with hormone receptor-positive early breast cancer.Methods: A retrospective analysis of 327 patients aged ≥65 years, with stage I-II, hormone receptor-positive breast cancer who underwent breast-conserving surgery and received endocrine therapy(ET) or radiotherapy plus endocrine therapy(ET+RT) was performed. Both groups were divided into luminal A type and luminal B type subgroups. Evaluation criteria were 5-year disease-free survival(DFS), local relapse rate(LRR), overall survival(OS), and distant metastasis rate(DMR).Results: There were significant differences in 5-year DFS [hazard ratio(HR)=1.59, 95% confidence interval(95% CI), 1.15-2.19;P=0.005] and LRR(HR=3.33, 95% CI, 1.51-7.34;P=0.003), whereas there were no significant differences in OS and DMR between ET group and ET+RT group. In luminal A type, there was no significant difference in 5-year DFS, LRR, OS and DMR between ET group and ET+RT group. In luminal B type,there were statistically significant differences in 5-year DFS(HR=2.19, 95% CI, 1.37-3.49;P=0.001), LRR(HR=5.45, 95% CI, 1.65-17.98;P=0.005), and OS(HR=1.75, 95% CI, 1.01-3.05;P=0.048) between ET group and ET+RT group. In the ET group, there were significant differences between luminal A type and luminal B type in5-year DFS(HR=1.84, 95% CI, 1.23-2.75;P=0.003) and OS(HR=1.76, 95% CI, 1.07-2.91;P=0.026).Conclusions: After breast-conserving surgery, radiotherapy can reduce the LRR and improve the DFS and OS of luminal B type elderly patients, whereas luminal A type elderly patients do not benefit from radiotherapy.Without radiotherapy, luminal A type patients have better DFS and OS than luminal B type patients.

联影URT-linac506c直线加速器在乳腺癌保乳手术后放疗中的应用价值

目的研究联影URT-linac506c直线加速器在乳腺癌保乳手术后放疗中的应用价值。方法回顾性选择2023年1—12月就诊于河南省人民医院的乳腺癌保乳手术后接受放射治疗的150例患者,随机分为两组,每组75例,对照组接受医科达infinity直线加速器,观察组接受联影URT-linac506c直线加速器。比较两种直线加速器照射误差、计划靶区的剂量参数、心脏、肺部与乳腺的受照剂量、照射反应。结果观察组X轴、Y轴、Z轴以及旋转角度误差均小于对照组(P<0.05)。两组D 1、D 99、D_(mena)剂量差异无统计学意义(P>0.05)。观察组适形指数、均匀性指数低于对照组(P<0.05)。两组心脏V 30、健侧乳腺D_(mena)照射剂量差异无统计学意义(P>0.05);观察组心脏D_(mena)、肺部患侧D_(mena)、V 30、健侧D_(mena)低于对照组(P<0.05)。所有患者均顺利完成放疗,未出现放疗终止的情况。观察组0~2度反应占比高于对照组(P<0.05),3级反应占比低于对照组(P<0.05)。两组4级反应差异无统计学意义(P>0.05)。结论乳腺癌保乳手术后采用联影URT-linac506c直线加速器放疗效果较好,可减小照射误差,降低计划靶区与危机器官的照射剂量,且皮肤照射反应程度较轻。

Latissimus Dorsi Mini-Flap as a Volume Replacement Technique after Partial Mastectomy for Breast Cancer in the Upper and Central Breast Quadrants: A Single Center Experience

Background: The latissimus dorsi (LD) muscle flap plays an essential role in breast reconstruction after partial mastectomy for cancer because of its stability and versatility. We evaluated both oncologic and aesthetic outcomes in addition to the related complications of this flap as an adjunct to breast conserving surgery in the management of breast cancer patients. Methods: All patients underwent a one-stage procedure with immediate reconstruction through two-steps operation;wider local excision utilizing oncoplastic principles and mini flap harvest & volume replacement. Results: The study included 34 cases with early breast cancer;30 patients had partial breast resection and defect refilling by LD mini-flap, three patients underwent mastectomy and one patient underwent extended LDF. The mean defect volume was (212.63 cm3 ± 59.57) cm3, while the mean flap volume was (218.27 cm3 ± 53.64 cm3). Patient self-evaluation of the cosmetic outcome was excellent in 20%, good in 60% and satisfactory in 20% of patients. Panel evaluation according to Harvard scale showed excellent in 36.7%, good in 36.7%, fair in 26.7% of patients. The median hospital stay was 4 days. The postoperative complications included wound gap in 4 patients (13.3%), postoperative donor site seroma in 16 patients (53.3%). No flap loss or necrosis, no affection on arm or shoulder mobility occurred. Lastly, no tumor recurrence till now. Conclusion: Latissimus dorsi mini-flap can achieve adequate cosmetic and oncologic outcomes with a low incidence of complications in patients with early stage (I/II) breast cancer and small to medium sized breasts.

乳腺癌保乳术后采用APBI-IMRT的效果

目的:探讨乳腺癌保乳术后采用加速部分乳腺调强放疗(accelerated partial breast irradiation with intensitymodulated radiation therapy,APBI-IMRT)的效果。方法:选择2018年6月—2022年9月南京大学医学院附属苏州医院收治的82例行乳腺癌保乳术患者作为研究对象,以随机数表法将患者分为对照组与研究组,各41例。对照组应用常规放疗,研究组应用APBI-IMRT,比较两组肿瘤标志物、危险器官剂量、心功能指标。结果:治疗前,两组肿瘤标志物、心功能指标比较,差异无统计学意义(P>0.05);治疗后,两组癌胚抗原(carcinoembryonic antigen,CEA)、β_(2)-微球蛋白(β_(2)-Microglobulin,β_(2)-MG)、细胞角蛋白19片段(cytokeratin 19 fragment,CYFRA21-1)、甲胎蛋白(alpha fetoprotein,AFP)水平、左房收缩末期内径(left atrial end-systolic diameter,LADs)、左室舒张末期内径(left ventricular end diastolic dimension,LVDD)、射血分数(ejection fraction,EF)、左心室短轴缩短率(fraction shortening,FS)较治疗前降低,且研究组肿瘤标志物低于对照组,但心功能指标高于对照组,差异有统计学意义(P<0.05)。研究组危险器官剂量低于对照组,差异有统计学意义(P<0.05)。结论:APBI-IMRT在乳腺癌保乳术后应用可增强治疗效果,降低对心肺功能的损伤。

Comparison of breast-conserving surgery and mastectomy in early breast cancer using observational data revisited:a propensity score-matched analysis

Recent observational studies showed that breast-conserving surgery(BCS) resulted in superior survival compared to mastectomy in breast cancer patients. This study compared the clinical outcomes of BCS and mastectomy using propensity score(PS)matching analysis, which had advantages over conventional methods in reducing bias. Nonmetastatic breast cancer patients who underwent BCS and mastectomy were matched 1:1 based on their PS. We used the Kaplan-Meier method and Cox-regression model to estimate the treatment effects. A total of 2,866 patients with a median follow-up time of 67 months were included in the original study population. Although the mastectomy cohort(N=1,219) had more advanced disease compared to the BCS cohort(N=1,647), LRFS was similar between the two groups(93.8% vs. 92.4%, P>0.05). BCS(vs. mastectomy) was associated with improved DFS(73.8% vs. 58.7%, P<0.01) and CSS(91% vs. 78.2%, P<0.01) in the original population. In the PS-matched population(N=1,668), clinicopathological features were equally distributed between the two cohorts. BCS(vs. mastectomy) was not associated with improved DFS(70.7% vs. 66.9%, P>0.05) or CSS(87.5% vs. 84.9%, P>0.05). We found that PS methods reduce bias when estimating treatment effects using observational data. BCS and mastectomy show equivalent outcomes in nonmetastatic breast cancer patients.