Patterns of Locoregional Failure in Patients With Operable Breast Cancer Treated by Mastectomy and Adjuvant Chemotherapy With or Without Tamoxifen and Without Radiotherapy: Results From Five National Surgical Adjuvant Breast and Bowel Project Randomized Clinical Trials

Assessment of Postmastectomy Radiation Therapy Receipt by Age and Association With Outcomes in Women With Breast Cancer

PURPOSE

Postmastectomy radiation therapy (PMRT) reduces locoregional recurrence (LRR) and improves overall survival (OS) in patients with breast cancer. Young age has been recognized as a risk factor for LRR. The primary objective of this study was to determine if recommendations for PMRT differed among patients younger than 50 years as compared to women aged 50 years or older.

METHODS

We reviewed medical records of patients with breast cancer who underwent mastectomy with or without PMRT from 2010 through 2018. Univariable and multivariable models were used to estimate the association of age with PMRT.

RESULTS

Of 2471 patients, 839 (34%) were <50 years; 1632 (66%) were ≥50 years. Patients <50 years had a higher percentage of grade 3 tumors, hormone receptor (HR) negative and/or Her-2/neu positive tumors, clinical stage T2/T3 tumors, and nodal involvement. Compared with patients ≥50 years, patients <50 years were more likely to undergo PMRT (OR 1.57; P = .001) and regional node irradiation (RNI) to the internal mammary nodes. Advanced clinical and pathologic stage, invasive tumor histology, the presence of lymphovascular invasion, and treatment with systemic chemotherapy were predictors of PMRT receipt for patients <50 years (P < .05). PMRT was associated with improved OS and recurrence free survival (RFS) among all patients (P < .01).

CONCLUSION

Patients <50 years were more likely to undergo PMRT and to receive RNI to the internal mammary nodes but were also more likely to have other risk factors for recurrence that would warrant a PMRT recommendation. PMRT improved OS and RFS for all patients.

Breast Cancer Presenting With Intravascular Tumor Emboli in Axillary Soft Tissue: Recurrence Risk and Radiation Therapy Outcomes

Purpose

Intravascular tumor emboli in axillary soft tissue (ITE) is a rare pathologic finding in breast cancer and is associated with higher axillary nodal disease burden. The independent prognostic and predictive value of this entity is unknown, as is the role of radiation therapy for ITE.

Methods and Materials

We analyzed a prospectively maintained database of breast cancer patients treated from 1992 to 2020. Patients with ITE were matched to those without (1:2) based on propensity scores to control for potential confounding factors. Locoregional (LRR) and distant recurrence (DR) were evaluated using competing risks methods accounting for death as a competing event. Overall survival (OS) and disease-free survival (DFS) were evaluated by Cox regression models. Among patients with ITE, we also evaluated whether RT improved outcomes.

Results

Among 2377 total patients, 129 had ITE, of whom 126 were propensity score matched to 252 without ITE. Median follow-up from time of surgery was 5.5 years (IQR 2.3, 9.7). There were no statistically significant differences in the 5-year incidence of LRR between groups (5.4% [95% CI, 1.6%-13%] with ITE vs 10% [95% CI, 6.7%-15%] without, P = .53) or DR (24% [95% CI, 15% 35%] with ITE vs 21% [95% CI, 16%-27%] without, P = .51). Five-year OS and DFS did not differ between groups (P > .9 for both comparisons, patients with ITE vs without ITE). In analyzing the effect of RT among patients with ITE, receipt of RT was associated with significantly improved DFS (HR, 0.34, 95% CI, 0.12-0.93, P = .04).

Conclusions

Patients with ITE do not exhibit significantly worse LRR, DR, DFS, or OS compared with a propensity-score-matched cohort without ITE. However, among patients with ITE, those who received RT demonstrated significantly improved DFS. Larger studies with longer follow-up are needed to evaluate the prognostic and predictive implications of ITE.

Skin perfusion and oxygen saturation after mastectomy and radiation therapy in breast cancer patients

The pathophysiological mechanism behind complications associated with postmastectomy radiotherapy (PMRT) and subsequent implant-based breast reconstruction are not completely understood. The aim of this study was to examine if there is a relationship between PMRT and microvascular perfusion and saturation in the skin after mastectomy and assess if there is impaired responsiveness to a topically applied vasodilator (Methyl nicotinate - MN). Skin microvascular perfusion and oxygenation >2 years after PMRT were measured using white light diffuse reflectance spectroscopy (DRS) and laser Doppler flowmetry (LDF) in the irradiated chest wall of 31 women with the contralateral breast as a control. In the non-irradiated breast, the perfusion after application of MN (median 0.84, 25th-75th centile 0.59-1.02 % RBC × mm/s) was higher compared to the irradiated chest wall (median 0.51, 25th-75th centile 0.21-0.68 % RBC × mm/s, p < 0.001). The same phenomenon was noted for saturation (median 91 %, 25th-75th centile 89-94 % compared to 89 % 25th-75th centile 77-93 %, p = 0.001). Eight of the women (26%) had a ≥10 % difference in skin oxygenation between the non-irradiated breast and the irradiated chest wall. These results indicate that late microvascular changes caused by radiotherapy of the chest wall significantly affect skin perfusion and oxygenation.

Does Post-Mastectomy Radiotherapy Confer Survival Benefits on Patients With 1-3 Clinically Positive Lymph Nodes Rendered Pathologically Negative After Neoadjuvant Systemic Chemotherapy: Consensus from A Pooled Analysis?

The advent of taxane-based chemotherapy has revolutionized breast cancer care. This advance has helped improve the response to downstaging tumors that might otherwise be inoperable. It has also helped in rendering clinically (cN+) positive lymph nodes (LNs) pathologically negative (ypN0). The standard of care for cN+ patients included post-mastectomy radiotherapy (PMRT), regardless of the response to neoadjuvant chemotherapy. However, PMRT in patients with 1-3 positive LNs still lacks definitive guidelines. Numerous retrospective results have been inconclusive about the benefit of PMRT on survival in patients with 1-3 positive LNs. This pooled analysis attempts to reach a consensus. The PubMed database was searched through October 2023. The search yielded 27 papers, of which 11 satisfied the inclusion criteria. The locoregional recurrence-free survival (LRRFS), disease-free survival (DFS), and overall survival (OS) for each study were tabulated when given, and two groups were created, the PMRT and NO PMRT, respectively. The results were then pooled for analysis. The total number of patients was 8340, 4136 in the PMRT group, and 4204 in the NO PMRT group, respectively. The LRRFS, DFS, and OS were 96.9%, 82.1%, and 87.3% for the PMRT group and 93.2%, 79.6%, and 84.8% for the NO PMRT group, respectively. There was no statistical significance in LRRFS, DFS, or OS between the two groups (p = 0.61, p = 0.61, and p = 0.38, respectively). PMRT does not seem to confer survival benefits in patients with pN1 rendered ypN0 for stages T1-3. This pooled analysis's findings should be confirmed prospectively with a longer period of follow-up.

Counselling Framework for Germline BRCA1/2 and PALB2 Carriers Considering Risk-Reducing Mastectomy

Female BRCA1/2 and PALB2 germline pathogenic variant carriers have an increased lifetime risk of breast cancer and may wish to consider risk-reducing mastectomy (RRM) for surgical prevention. Quantifying the residual lifetime risk and absolute benefit from RRM requires careful consideration of a patient's age, pathogenic variant, and their personal history of breast or ovarian cancer. Historically, patients have been counselled that RRM does not necessarily prolong survival relative to high-risk surveillance, although recent studies suggest a possible survival benefit of RRM in BRCA1 carriers. The uptake of RRM has increased dramatically over the last several decades yet varies according to sociodemographic factors and geographic region. The increased adoption of nipple-sparing mastectomy techniques, ability to avoid axillary staging, and availability of reconstructive options for most germline pathogenic variant carriers has helped to minimize the morbidity of RRM. Preoperative discussions should include evidence regarding postmastectomy sensation, the potential for supplemental surgery, pregnancy-related chest wall changes, and the need for continued clinical surveillance. Approaches that include sensation preservation and robotic nipple-sparing mastectomy are an area of evolving research that may be more widely adopted in the future.

Clinicopathological characteristics and features of molecular subtypes of breast cancer at high altitudes

Background

Breast cancer is one of the major malignancies threatening women's health worldwide. The incidence of breast cancer at high altitudes increased over the years. But few studies focused on the characteristics of clinicopathology and molecular subtypes among breast cancer at high altitudes, which are still unknown. Tibet, with an average altitude over 4000 meters, is a representative city at high altitudes, lying in the Qinghai-Tibetan Plateau in southwestern China. This study aimed to identify the clinicopathological characteristics and features of molecular subtypes among Tibetan women with breast cancer, and provide evidence for cancer prevention and personalized therapeutics in high-altitude regions.

Methods

Between May 2013 and March 2022, 104 Tibetan women from high-altitude regions (Tibetan-group) and 34 Han Chinese women from low-altitude regions (Han-group), consecutively diagnosed with breast cancer in the Hospital of Chengdu Office of People's Government of Tibetan Autonomous Region, were included in the study. We retrospectively reviewed the clinical character, altitudes of residence, tumor size, lymph nodes metastasis, distant metastasis, pathological type, immunohistochemical index, and molecular subtype.

Results

In the study, we calculated the patient delay, equal to the period from symptoms onset to hospital visits. The patient delay of Tibetan-group was 7.47 ± 11.53 months, which was significantly longer than that of Han-group, 7.22 ± 22.96 months (p<0.05). Body Mass Index (BMI) was significantly different (p<0.05). Tumors in Tibetan-group were significantly larger than those in Han-group, 4.13 ± 2.98cm and 2.51 ± 0.82cm in diameter, respectively (p<0.05). According to ordinal logistic regression analysis, exposure to high altitudes might result in more advanced T stage (OR=2.45 95%CI 1.10-5.44). 41.3% (43/104) of cases in Tibetan-group had lymph node positive disease, whereas the percentage was found in 38.26% (13/34) in Han-group(p<0.05). The distribution of molecular subtypes was quite significantly different between two groups (p<0.05), according to the comparison of constituent ratios.

Conclusion

Our study verified that breast cancer at high altitudes possessed its own unique clinicopathological characteristics and distinct features of molecular subtypes. It broadened the understanding of this heterogenous disease and also provided valuable evidence for cancer prevention and personalized therapeutics of breast cancer at high altitudes.

Randomized clinical trial of tissue equivalent bolus prescription in postmastectomy radiotherapy stratified by skin involvement status

Purpose

To assess the impact and optimize the prescription of tissue-equivalent bolus in postmastectomy radiotherapy (PMRT), we compared the use of different bolus regimens tailored by skin involvement status.

Methods

Patients with breast cancer who required PMRT were recruited (NCT01925651) and classified into two groups: standard-risk (SR, without skin involvement) and high-risk (HR, with skin involvement). SR was randomized between no bolus or 5 mm-bolus on alternate days and HR between 5 mm-bolus on alternate days or daily. Conventional fractionation (50.4 Gy; 1.8 Gy/daily) was used. Acute skin toxicity was evaluated blindly and the radiodermatitis-specific toxicity index [rads-TI] calculated. Subsequently, patients were followed up to assess oncologic outcomes, focusing on chest wall (CW) local control.

Results

Fifty-eight patients were enrolled (34 SR and 24 HR). Baseline characteristics were similar between arms within the same risk group. Overall, maximal radiodermatitis rates were 29.4 % (G2) and 15.7 % (G3). In the SR group, no difference existed in G2 radiodermatitis incidence between the subgroups (p = 0.70) and no G3 events occurred. In the HR group, incidences of G2 (100 % vs 44.5 %, p = 0.01) and G3 radiodermatitis (70 % vs 11.1 %, p = 0.02) were higher with daily bolus. After adjusting for confounders, the daily bolus had a higher incidence of G2 (p = 0.03), G3 radiodermatitis (p = 0.04), and worse rads-TI (p < 0.01). After a median follow-up of 6.2 years, the 5-year local control was 95.8 % (95 %CI: 88.2 %-100 %) in the SR and 91.7 % (95 %CI: 77.3 %-100 %) in the HR groups. Per risk group, there was no difference in local control between the SR (p = 0.90) or the HR bolus regimens (p = 0.70).

Conclusion

Daily 5 mm bolus prescription significantly increased the overall toxicity burden. In this preliminary study, within the same risk group, no detriment in CW local control was detected with less intense bolus regimens (SR: no bolus; HR: alternate-days bolus). Additionally, the rads-TI was able to distinguish overall radiodermatitis burden.

Risk factors to identify the indication for regional nodal irradiation in T1-2N1M0 breast cancer: A joint analysis of 4,243 real-world cases from two institutions

Purpose

The aim of this study is to evaluate the role of regional nodal irradiation (RNI) in patients with T1-2N1M0 breast cancer and to identify the subgroup that could benefit from RNI.

Methods and materials

A total of 4,243 women with pT1-2N1M0 breast cancer treated at two institutions in China were retrospectively reviewed. Survival rates were calculated by the Kaplan-Meier method and compared by the log-rank test. The association of risk factors with survival outcomes was evaluated using multivariable proportional hazards regression.

Results

A total of 932 patients (22.0%) received RNI. At a median follow-up of 5.9 years, the 5-year locoregional recurrence (LRR), distant metastasis (DM), disease-free survival (DFS), and overall survival (OS) rates were 4.0% and 7.2% (P = 0.001), 13.2% and 10.6% (P = 0.465), 85.0% and 84.7% (P = 0.131), and 93.9% and 92.8% (P = 0.004) in the RNI and non-RNI groups, respectively. Multivariate analysis revealed that RNI was an independent prognostic factor for lower LRR (P = 0.001) and longer DFS (P = 0.013). Patients were stratified into low-, intermediate-, and high-risk groups based on the eight non-therapeutic risk factors. RNI significantly decreased the 5-year LRR (2.2% vs. 7.0%, P = 0.001) and improved the 5-year DFS (88.8% vs. 84.9%, P = 0.015) and OS (95.8% vs. 93.9%, P = 0.010) in the intermediate-risk group. However, neither the low-risk group nor the high-risk group had survival benefit from RNI.

Conclusion

T1-2N1M0 breast cancer is a heterogeneous disease. We found that RNI only improved survival in the intermediate-risk group. It might be omitted in low-risk patients, and the role of RNI in high-risk patients needs further study.

Association of 21-gene recurrence score and locoregional recurrence in early breast cancer patients

BACKGROUND: The 21-gene recurrence score (RS) assay has been validated to predict the risk of disease-free survival in estrogen receptor (ER)-positive, human epidermal growth factor receptor 2 (HER2)-negative early breast cancer patients. However, its relation with locoregional recurrence (LRR) risk is unclear. OBJECTIVE: This study aimed to explore the ability of RS to predict LRR risk. METHODS: Consecutive ER-positive, HER2-negative, pT1, pN0-1, and M0 early breast cancer patients were analyzed retrospectively. According to RS, patients were divided into low- (RS < 18), intermediate- (RS 18–30), and high-risk (RS ⩾ 31) groups. The primary endpoint was LRR. Subgroup analysis was conducted according to different nodal statuses and surgery types. RESULTS: A total of 1558 patients were enrolled: 354 (22.7%), 788 (50.6%), and 416 (26.7%) patients in the low-, intermediate-, and high-risk groups, respectively. The median follow-up time was 53 months, and 2, 8, and 14 LRR events were observed in the low-, intermediate-, and high-risk groups, respectively (P= 0.004). Both univariate (P= 0.009) and multivariate (P= 0.010) analyses demonstrated that 21-gene RS was correlated with LRR. Compared to low-risk patients, high-risk patients were at greater risk of LRR (HR 5.75, 95% CI 1.30–25.31, P= 0.021). Among pN0 (P= 0.033), pN1 (P= 0.049) and postmastectomy patients (P= 0.012), 21-gene RS remained predictive of the risk of LRR. CONCLUSION: The 21-gene RS assay was significantly associated with the risk of LRR in ER-positive, HER2-negative early breast cancer patients. Among patients with different nodal statuses and patients receiving mastectomy, RS remained predictive of the risk of LRR.

Prognostic impact of postoperative radiotherapy in patients with breast cancer and with pT1-2 and 1-3 lymph node metastases: A retrospective cohort study based on the Japanese Breast Cancer Registry

AIM

Postmastectomy radiotherapy (PMRT) is the standard treatment for locally advanced breast cancer. However, the effectiveness of PMRT in patients with pT1-2 and N1 tumours remains controversial. Therefore, this study aimed to determine the prognostic impact of PMRT in patients with breast cancer and with pT1-2 and 1-3 lymph node metastases.

METHODS

Using data from the Japanese National Clinical Database from 2004 to 2012, we evaluated the association of PMRT with locoregional recurrence (LRR), any recurrence, and mortality. We enrolled patients who had undergone mastectomy and axillary node dissection and were diagnosed with pT1-2 and N1. We compared clinicopathological factors and prognosis between patients who received (PMRT group) and those who did not receive (No-PMRT group) PMRT.

RESULTS

Among 8914 patients enrolled, 492 patients belonged to the PMRT group and 8422 to the No-PMRT group. The median observation time was 6.3 years. There was no significant difference in the incidences of LRR (4.0% versus 5.0%, P = 0.61), recurrence (13.8% versus 11.8%, P = 0.23) and breast cancer death (6.0% versus 4.3%, P = 0.08) at 5 years between the groups. Multivariable analysis revealed that LRR was significantly associated with tumour size, number of node metastases and triple-negative subtype but not with PMRT.

CONCLUSIONS

The LRR rate in the No-PMRT group was 5.0% at 5 years among patients with T1-2 and N1. PMRT did not significantly influence LRR in patients with T1-2 and N1. However, PMRT administration should be tailored considering the individual risks of tumour size, 3 node metastases and triple-negative subtype.

Effect of Elective Internal Mammary Node Irradiation on Disease-Free Survival in Women With Node-Positive Breast Cancer: A Randomized Phase 3 Clinical Trial

IMPORTANCE

The benefit of internal mammary node irradiation (IMNI) for treatment outcomes in node-positive breast cancer is unknown.

OBJECTIVE

To investigate whether the inclusion of IMNI in regional nodal irradiation improves disease-free survival (DFS) in women with node-positive breast cancer.

DESIGN, SETTING, AND PARTICIPANTS

This multicenter, phase 3 randomized clinical trial was conducted from June 1, 2008, to February 29, 2020, at 13 hospitals in South Korea. Women with pathologically confirmed, node-positive breast cancer after breast-conservation surgery or mastectomy with axillary lymph node dissection were eligible and enrolled between November 19, 2008, and January 14, 2013. Patients with distant metastasis and those who had received neoadjuvant treatment were excluded. Data analyses were performed according to the intention-to-treat principle.

INTERVENTIONS

All patients underwent regional nodal irradiation along with breast or chest wall irradiation. They were randomized 1:1 to receive radiotherapy either with IMNI or without IMNI.

MAIN OUTCOMES AND MEASURES

The primary end point was the 7-year DFS. Secondary end points included the rates of overall survival, breast cancer-specific survival, and toxic effects.

RESULTS

A total of 735 women (mean [SD] age, 49.0 [9.1] years) were included in the analyses, of whom 373 received regional nodal irradiation without IMNI and 362 received regional nodal irradiation with IMNI. Nearly all patients underwent taxane-based adjuvant systemic treatment. The median (IQR) follow-up was 100.4 (89.7-112.1) months. The 7-year DFS rates did not significantly differ between the groups treated without IMNI and with IMNI (81.9% vs 85.3%; hazard ratio [HR], 0.80; 95% CI, 0.57-1.14; log-rank P = .22). However, an ad hoc subgroup analysis showed significantly higher DFS rates with IMNI among patients with mediocentrally located tumors. In this subgroup, the 7-year DFS rates were 81.6% without IMNI vs 91.8% with IMNI (HR, 0.42; 95% CI, 0.22-0.82; log-rank P = .008), and the 7-year breast cancer mortality rates were 10.2% without IMNI vs 4.9% with IMNI (HR, 0.41; 95% CI, 0.17-0.99; log-rank P = .04). No differences were found between the 2 groups in the incidence of adverse effects, including cardiac toxic effects and radiation pneumonitis.

CONCLUSIONS AND RELEVANCE

This randomized clinical trial found that including IMNI in regional nodal irradiation did not significantly improve the DFS in patients with node-positive breast cancer. However, patients with medially or centrally located tumors may benefit from the use of IMNI.

TRIAL REGISTRATION

ClinicalTrials.gov Identifier: NCT04803266.

The effect of postmastectomy radiation therapy on high-risk patients with T1-2N0 breast cancer

BACKGROUND

The prognostic impact of postmastectomy radiation therapy (PMRT) on high-risk patients with T1-2N0 breast cancer is controversial. We aimed to investigate the effect of PMRT on high-risk patients with T1-2N0 breast cancer.

METHODS

A total of 3439 patients diagnosed with T1-2N0 breast cancer who received mastectomy between 2000 and 2016 in our institute were retrospectively analyzed. Leveraging the Fine and Gray competing risks regression in unirradiated patients, risk factors of locoregional recurrence (LRR) were identified. All patients were stratified into high-risk (3 or 4 risk factors) and low-risk (no more than 2 risk factors) groups. The prognostic effect of PMRT was estimated in two subgroups. This subgroup analysis was also performed in patients with T2N0 breast cancer.

RESULTS

The median follow-up was 89 months. The 5-year cumulative incidence of LRR was 2.2% in unirradiated patients. Tumor size, estrogen receptor (ER) status, histologic grade and lymphovascular invasion (LVI) were identified as independent risk factors of LRR. In the high-risk group, PMRT was correlated with a 8.3% risk reduction of 5-year LRR, 7.8% risk reduction of 5-year distant recurrence (DR), and 6.4% risk reduction of 5-year breast cancer mortality (BCM), whereas it was not correlated with LRR, DR, or BCM in low-risk group. In patients with T2N0 breast cancer, PMRT was associated with decreased LRR, DR and BCM in high-risk group, other than low-risk group.

CONCLUSIONS

PMRT presented heterogenous effect on patients with T1-2N0 breast cancer. Patients at high risk of LRR were more likely to benefit from PMRT.

Diverse Distribution and Gene Expression on the 21-Gene Recurrence Assay in Breast Cancer Patients with Locoregional Recurrence Versus Distant Metastasis

Background

It remains uncertain whether the 21-gene recurrence score (RS) of a primary tumor has selective prognostic value for locoregional recurrence (LRR) or distant metastasis (DM). The current study aimed to compare the distribution and single-gene expression on the RS panel in breast cancer patients with LRR versus DM.

Methods

Consecutive early breast cancer patients who had been operated on at the Comprehensive Breast Health Center, Ruijin Hospital from January 2009 to December 2016 were retrospectively reviewed. Patients were divided into LRR, DM, and no-recurrence groups according to the first reported recurrent event. Comparison and subgroup analysis of 21-gene RS, RS category, and single-gene expression on the RS panel were conducted among patients with different recurrence status.

Results

A total of 1,287 patients were included, with median follow-up of 61.5 months, and 27, 47, and 1,213 patients were classified as LRR, DM, and no recurrence groups, respectively. RS was significantly diversely distributed among the three groups (P<0.001). No-recurrence patients (median 22) presented much lower RS than LRR (median 39, P<0.001) and DM (median 30, P<0.001) patients. LRR patients had lower PR (P<0.001), BCL2 (P=0.010), and CEGP1 (P<0.001) expression, and DM patients had higher STMY3 (P=0.019) expression than no-recurrence patients. Moreover, CEGP1 expression was significantly lower in the LRR group than the DM one (P=0.028).

Conclusion

RS was differently distributed between recurrent and nonrecurrent patients. PR, BCL2, CEGP1, and STMY3 expression was associated with LRR and DM, while CEGP1 was lower in the LRR group than DM patients, warranting further clinical evaluation.

Effects of radiation on toxicity, complications, revision surgery and aesthetic outcomes in breast reconstruction: An argument about timing and techniques

BACKGROUND

Radiotherapy (RT) combined with breast reconstruction can reduce the risk of cancer recurrence and increase the survival rate. However, this approach seems to worsen aesthetic outcomes and increase complication rates. The impact of breast reconstruction timing and techniques on clinical outcomes, however, remains unclear. For this reason, we aimed to perform a more comprehensive analysis of a series of patients undergoing RT and breast reconstruction.

METHODS

Patients were divided into 4 groups according to the timing of reconstruction (before RT and after RT) and surgical technique (heterologous reconstruction and autologous reconstruction (AR)). The median time between RT and reconstruction, number of revision surgeries, incidence of complications, toxicity, aesthetics and associated clinical risk factors were used to assess the clinical outcomes. An objective system of skin toxicity evaluation was performed.

RESULTS

Ninety-five patients were included in this study. No significant differences in the median time between RT and reconstruction, incidence of complications, toxicity or aesthetics were noted between different timings or techniques of reconstruction. Patients undergoing AR needed more revision surgeries to complete reconstruction. However, the total number of surgical procedures was similar between the groups. In a comparison between the treated and untreated breasts by an objective system, RT produced an increase in erythema and pigmentation and a decrease in elasticity in the treated breast (p<0.05 for all parameters). On multivariate analysis, smoking was a significant predictor associated with complications.

CONCLUSIONS

Combined breast reconstruction and RT seem to be successful regardless of the order of treatment or the type of reconstruction.

Patterns of supraclavicular area failure after mastectomy in breast cancer patients: implications for target volume delineation

Purpose

To characterize the pattern of post-mastectomy supraclavicular lymph node (LN) metastases in patients with breast cancer (BC) and to provide insights for individualized clinical target volume delineation for radiotherapy.

Methods

We retrospectively analyzed 88 patients with BC who developed post-mastectomy regional LN metastases. The affected regional LNs were categorized as the ipsilateral medial supraclavicular LN area (IMSC-LN), ipsilateral lateral supraclavicular LN area (ILSC-LN), ipsilateral infraclavicular LN area (IIC-LN), and ≥2 groups in the ipsilateral clavicular LN area (MMIC-LN). Clinical characteristics were included in a multivariate analysis to identify risk factors for clavicular LN metastases.

Results

The ILSC-LNs (68.2%) were the most common metastatic site. IMSC-LN metastases showed a significant association with estrogen-receptor (ER) negative status, left-sided BC, and positive axillary LNs. Tumor size ≥2.4 cm and Her2 type were predictors of ILSC-LN metastases. Additionally, tumor size ≥2.4 cm, and level I ipsilateral axillary metastases were associated with MMIC-LN metastasis.

Conclusion

ILSC-LN was the most frequently affected group of supraclavicular lymph nodes. ER-negative status, left-sided BC, tumor size, and positive ipsilateral axillary LNs are potentially associated with the pattern of supraclavicular LN metastatic involvement.

A Prognostic Risk Stratification Model to Identify Potential Population Benefiting From Postmastectomy Radiotherapy in T1-2 Breast Cancer With 1-3 Positive Axillary Lymph Nodes

Background and Objectives

To establish a prognostic stratification nomogram for T1–2 breast cancer with 1–3 positive lymph nodes to determine which patients can benefit from postmastectomy radiotherapy (PMRT).

Methods

A population-based study was conducted utilizing data collected from the Surveillance, Epidemiology, and End Results database. Chi-square test or Fisher exact test was used to compare the distribution of characteristics. Cox analysis identified significant prognostic factors for survival. A prognostic stratification model was constructed by R software. Propensity score matching was applied to balance characteristics between PMRT cohort and control cohort. Kaplan-Meier method was performed to evaluate the performance of stratification and the benefits of PMRT in the total population and three risk groups.

Results

The overall performance of the nomogram was good (3-year, 5-year, 10-year AUC were 0.75, 0.72 and 0.67, respectively). The nomogram was performed to excellently distinguish low-risk, moderate-risk, and high-risk groups with 10-year overall survival (OS) of 86.9%, 73.7%, and 62.7%, respectively (P<0.001). In the high-risk group, PMRT can significantly better OS with 10-year all-cause mortality reduced by 6.7% (P = 0.027). However, there was no significant survival difference between PMRT cohort and control cohort in low-risk (P=0.49) and moderate-risk groups (P = 0.35).

Conclusion

The current study developed the first prognostic stratification nomogram for T1–2 breast cancer with 1–3 positive axillary lymph nodes and found that patients in the high-risk group may be easier to benefit from PMRT.

Radiomics of Tumor Heterogeneity in Longitudinal Dynamic Contrast-Enhanced Magnetic Resonance Imaging for Predicting Response to Neoadjuvant Chemotherapy in Breast Cancer

Breast tumor morphological and vascular characteristics can be changed during neoadjuvant chemotherapy (NACT). The early changes in tumor heterogeneity can be quantitatively modeled by longitudinal dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI), which is useful in predicting responses to NACT in breast cancer. In this retrospective analysis, 114 female patients with unilateral unifocal primary breast cancer who received NACT were included in a development (n = 61) dataset and a testing dataset (n = 53). DCE-MRI was performed for each patient before and after treatment (two cycles of NACT) to generate baseline and early follow-up images, respectively. Feature-level changes (delta) of the entire tumor were evaluated by calculating the relative net feature change (deltaRAD) between baseline and follow-up images. The voxel-level change inside the tumor was evaluated, which yielded a Jacobian map by registering the follow-up image to the baseline image. Clinical information and the radiomic features were fused to enhance the predictive performance. The area under the curve (AUC) values were assessed to evaluate the prediction performance. Predictive models using radiomics based on pre- and post-treatment images, Jacobian maps and deltaRAD showed AUC values of 0.568, 0.767, 0.630 and 0.726, respectively. When features from these images were fused, the predictive model generated an AUC value of 0.771. After adding the molecular subtype information in the fused model, the performance was increased to an AUC of 0.809 (sensitivity of 0.826 and specificity of 0.800), which is significantly higher than that of the baseline imaging- and Jacobian map-based predictive models (p = 0.028 and 0.019, respectively). The level of tumor heterogeneity reduction (evaluated by texture feature) is higher in the NACT responders than in the nonresponders. The results suggested that changes in DCE-MRI features that reflect a reduction in tumor heterogeneity following NACT could provide early prediction of breast tumor response. The prediction was improved when the molecular subtype information was combined into the model.

Discordance between Primary Breast Cancer and Ipsilateral Breast Cancer Tumor Recurrence as a Function of Distance

Background: Risk factors for ipsilateral breast cancer tumor recurrence (IBTR) are well established and include grading, nodal status, and receptor status. Little is known about the influence of the local distance between the primary tumor and recurrences on changes in tumor characteristics and prognosis. Methods: In a retrospective setting, we analyzed primary breast cancers and their recurrences. Localizations of primary and recurrent breast cancer were recorded to calculate the relative distance in pixels. Analysis was performed regarding tumor characteristics, relative distance between both, and their impact on breast cancer prognosis. Results: In a cohort of 142 patients with ipsilateral recurrence, no statistically significant difference could be shown in the change in tumor characteristics depending on distance. Progesterone receptor (PR) and estrogene receptor (ER) status changed in 22.7% and 14.9% of cases, respectively. human epidermal growth factor receptor 2 (ERBB2, HER2) status changed in 18.3% of cases. Survival was in accordance with the literature, with luminal-A-like tumors as best and triple negative breast cancers (TNBC) as worst prognosis. With a threshold of 162 pixels, the survival was significantly better in the group with shorter distance. Conclusion: Change in tumor characteristics from primary breast cancer to recurrence occurs more often in PR than ER. In contrast to other work, in this dataset, recurrences with a larger distance to the primary tumor had a worse prognosis in univariate analysis. A Cox model might indicate the possibility that this influence is independent of other risk factors.

Risk-Adapted Postmastectomy Radiotherapy Decision Based on Prognostic Nomogram for pT1-2N1M0 Breast Cancer: A Multicenter Study

PURPOSE

The aim of this study was to develop a widely accepted prognostic nomogram and establish a risk-adapted PMRT strategy based on locoregional recurrence for pT1-2N1M0 breast cancer.

METHODS AND MATERIALS

A total of 3,033 patients with pT1-2N1M0 breast cancer treated at 6 participating institutions between 2000 and 2016 were retrospectively reviewed. A nomogram was developed to predicted locoregional recurrence-free survival (LRFS). A propensity score-matched (PSM) analyses was performed in risk-adapted model.

RESULTS

With the median follow-up of 65.0 months, the 5-year overall survival (OS), disease free survival (DFS) and LRFS were 93.0, 84.8, and 93.6%, respectively. There was no significant difference between patients who received PMRT or not for the entire group. A nomogram was developed and validated to estimate the probability of 5-year LRFS based on five independent factors including age, primary tumor site, positive lymph nodes number, pathological T stage, and molecular subtype that were selected by a multivariate analysis of patients who did not receive PMRT in the primary cohort. According to the total nomogram risk scores, the entire patients were classified into low- (40.0%), moderate- (42.4%), and high-risk group (17.6%). The 5-year outcomes were significantly different among these three groups (P<0.001). In low-risk group, patients who received PMRT or not both achieved a favorable OS, DFS, and LRFS. In moderate-risk group, no differences in OS, DFS, and LRFS were observed between PMRT and no PMRT patients. In high-risk group, compared with no PMRT, PMRT resulted in significantly different OS (86.8 vs 83.9%, P = 0.050), DFS (77.2 vs 70.9%, P = 0.049), and LRFS (90.8 vs. 81.6%, P = 0.003). After PSM adjustment, there were no significant differences in OS, DFS, and LRFS in low-risk and moderate-risk groups. However, in the high-risk group, PMRT still resulted in significantly better OS, DFS and improved LRFS.

CONCLUSIONS

The proposed nomogram provides an individualized risk estimate of LRFS in patients with pT1-2N1M0 breast cancer. Risk-adapted PMRT for high-risk patients is a viable effective strategy.

Does Failure to Achieve Pathologic Complete Response with Neoadjuvant Chemotherapy Identify Node-Negative Patients Who Would Benefit from Postmastectomy Radiation or Regional Nodal Irradiation?

BACKGROUND

Postmastectomy radiation (PMRT) and regional nodal irradiation (RNI) improve outcomes for patients at high risk of locoregional recurrence (LRR). Node-negative patients with the triple-negative (TN) subtype and those who do not have a pCR with neoadjuvant chemotherapy (NAC) are at increased risk for LRR, but whether the absolute risk for LRR is high enough to justify PMRT/RNI is uncertain.

METHODS

Patients with cT1-T3N0 and pN0 disease treated with NAC who had residual disease in the breast were identified from a prospective database. Patients were eligible for the study if they had mastectomy or breast-conserving therapy with negative margins and whole-breast radiation. Those receiving PMRT or RNI were excluded. Actuarial rates were estimated using the cumulative incidence function.

RESULTS

The 227 patients in this study had a mean age was 51.4 ± 12.6 years, and 82 (36.1%) were TN. During a median follow-up period of 35 months, nine LRR events occurred. The overall crude and actuarial 3-year LRR rates were 4.4% and 5.9%, respectively. The crude LRR rate for the TN patients was 7.4%, and the 3-year actuarial rate was 10.1%. The hormone receptor-positive (HR+) and human epidermal growth factor receptor 2-negative (HER2-) patients had a crude LRR rate of 2.8% and a 3-year actuarial rate of 3.2%. The HER2+ patients had a crude LRR rate of 2.7% and a 3-year actuarial rate of 3.3%.

CONCLUSIONS

Locoregional recurrence is uncommon for patients with node-negative HR+/HER2- and HER2+ tumors who have residual disease in the breast; however, TN patients have LRR rates that approach 10% at 3 years, suggesting a possible role for PMRT/RNI for node-negative TN patients. Additional follow-up with more patients is needed for definitive conclusions.

Prognostic factors for breast cancer patients with T1-2 tumors and 1-3 positive lymph nodes and the role of postmastectomy radiotherapy in these patients

PURPOSE

The purpose of this study was to identify independent prognostic factors for breast cancer patients with T1-2 tumors and 1-3 positive lymph nodes, and discuss the role of postmastectomy radiotherapy(PMRT) in these patients.

METHODS

Between January 2005 and December 2015, the data on 840 eligible patients with breast cancer were retrospectively reviewed. Of these patients, 368 women received PMRT and 472 did not. The endpoints were locoregional recurrence (LRR) and distant metastasis (DM).

RESULTS

With a median follow-up of 62.0 months, multivariate analysis identified the following independent risk factors for increased LRR: tumor size ≥ 4 cm (HR: 2.994, 95% CI: 1.190-7.535, P = 0.020), ER- and PR-negative tumor (HR: 2.540, 95% CI: 1.165-5.537, P = 0.019), preoperative high neutrophil-to-lymphocyte ratio (NLR) (HR: 4.716, 95% CI: 1.776-12.528, P = 0.002)and low neutrophil-to-monocyte ratio (NMR) (HR: 0.231, 95% CI: 0.084-0.633, P = 0.004). And independent risk factors for increased DM: ER- and PR-negative tumor (HR: 2.540, 95% CI: 1.880-5.625, P = 0.000), high NLR (HR: 2.693, 95% CI: 1.426-5.084, P = 0.002) and low NMR (HR: 0.460, 95% CI: 0.257-0.824, P = 0.009). The high-risk patients (≥ 2 risk factors) had worse LRRFS and DFS than low-risk patients (0-1 risk factor) (all, P < 0.05). In the subgroup analysis, both low- and high-risk patients received PMRT had better LRRFS and DFS than those who without PMRT (all, P < 0.05), and the high-risk patients received PMRT had similar 5-year rates of LRRFS and DFS than low-risk patients who without PMRT (94.5 vs. 94.3%, P = 0.402; 83.4 vs.87.4%, P = 0.877, respectively).

CONCLUSIONS

Tumor size, ER/PR status, preoperative NLR and NMR were independent predictors of risk of recurrence. PMRT could improve locoregional control even in low-risk subgroup of breast cancer patients with T1-2 tumors and 1-3 positive lymph nodes significantly.

Locoregional recurrence patterns in women with breast cancer who have not undergone post-mastectomy radiotherapy

Background

To analyze the patterns of locoregional recurrence in breast cancer patients after mastectomy.

Methods

The retrospective study included 7073 women with breast cancer without post-mastectomy radiotherapy: 4604 (65.1%) had pT1–2 N0 disease (low risk); 2042 (28.9%), pT1–2 N1 (intermediate risk); and 427 (6.0%), pT3–4 and/or pN2–3, or pT1–2 N1 after neoadjuvant chemotherapy (high risk). The distribution of cumulative locoregional recurrence was analyzed. The local recurrence and regional recurrence rates were estimated by the Kaplan-Meier method, and differences were compared with the log-rank test. Multivariate analysis was performed using Cox logistic regression analysis.

Results

In the median follow-up of 63.0 months, 469 patients had locoregional recurrence: chest wall recurrence in 238 (50.7%) cases, supraclavicular/infraclavicular nodes in 236 (50.3%) cases, axilla in 92 (19.6%), and internal mammary nodes in 50 (10.7%) cases. The 5-year local recurrence and regional recurrence rates were 2.5 and 4.4%, respectively. Subgroup analysis of the three risk groups and five molecular subtypes (luminal A, luminal B-Her2 negative, luminal B-Her2 positive, Her2-enriched, and triple negative) also showed that the chest wall and supraclavicular/infraclavicular nodes were the most common recurrence sites. Age, tumor location, T stage, N stage, and hormone receptor status were independent prognostic factors for both local recurrence and regional recurrence (p < 0.05).

Conclusions

The chest wall and supraclavicular/infraclavicular nodes are common sites of locoregional recurrence in breast cancer, irrespective of disease stage or molecular subtype, and the prognostic factors for local recurrence and regional recurrence are similar. Therefore, chest wall and supraclavicular/infraclavicular nodes irradiation should always be considered in post-mastectomy radiotherapy.

Utility of regional nodal irradiation in Japanese patients with breast cancer with 1-3 positive nodes after breast-conserving surgery and axillary lymph-node dissection

The utility of regional nodal irradiation (RNI) is being considered in cases of 1-3 axillary node metastases after breast-conserving surgery (BCS) with axillary lymph-node dissection (ALND). Therefore, we examined the necessity of RNI by examining the sites of recurrences in cases at our institution. We retrospectively analyzed 5,164 cases of primary breast cancer between January 2000 and December 2014 at the Aichi Cancer Centre, identifying local and distant recurrences in 152 patients with primary breast cancer treated with BCS and ALND and who had 1-3 positive axillary nodes. All patients received whole-breast irradiation (WBI) and adjuvant systemic therapy with either chemotherapy or anti-endocrine therapy with or without anti-human epidermal growth factor receptor 2 therapy. The present study excluded patients with ipsilateral breast tumor recurrence, contralateral breast cancer, neoadjuvant chemotherapy, T4 tumors or N2-3 nodes and distant metastasis. From the database of our institution, we identified 152 cases that met the defined criteria. The median follow-up period was 71 months (1-176). Isolated locoregional recurrences were found in three patients (2.0%) and were recurrent only in the breast. Only one patient had local lymph node recurrence with distant recurrence. The 10-year rates of isolated regional disease-free survival (DFS), DFS, and overall survival were 95.41, 89.50 and 96.75%, respectively, which was better compared with previous studies. We conclude that the addition of RNI to WBI is not necessary for Japanese patients who have 1-3 positive axillary nodes and ALND.

The prognostic and predictive role of 21-gene recurrence scores in hormone receptor-positive early-stage breast cancer

Over the past two decades, gene expression profiling of breast cancer has emerged as an important tool in early-stage breast cancer management. The approach provides important information on underlying biological mechanisms, breast cancer classification, future risk potential of developing recurrent metastatic disease, and provides beneficial clues for adjuvant chemotherapy in hormone receptor (HR) positive breast cancer. Of the commercially available genomic tests for breast cancer, the prognostic and predictive value of 21-gene recurrence score tests have been validated using both retrospective data and prospective clinical trials. In this paper, we reviewed the current evidence on 21-gene expression profiles for HR-positive HER2-negative early-stage breast cancer management. We show that current evidence supports endocrine therapy alone as an appropriate adjuvant systemic therapy for approximately 70% of women with HR-positive, HER2-negative, node-negative breast cancer. Evolving evidence also suggests that 21-gene recurrence scores have predictive values for node-positive breast cancer and that chemotherapy can be avoided in more than half of women with nodes 1 to 3 positive HR-positive breast cancer. Furthermore, retrospective data also supports the predictive role of 21-gene recurrence scores for adjuvant radiation therapy. A prospective trial in this area is ongoing.

Locoregional recurrence risk after neoadjuvant chemotherapy: A pooled analysis of nine prospective neoadjuvant breast cancer trials

AIM

This pooled analysis aimed to evaluate locoregional recurrence (LRR) rates of breast cancer (BC) after neoadjuvant chemotherapy (NACT) and to identify independent LRR predictors.

METHODS

10,075 women with primary BC from nine neoadjuvant trials were included. The primary outcome was the cumulative incidence rate of LRR as the first event after NACT. Distant recurrence, secondary malignancy or death were defined as competing events. For identifying LRR predictors, surgery type, pathological complete response (pCR), BC subtypes and other potential risk factors were evaluated.

RESULTS

Median followup was 67 months (range 0-215), overall LRR rate was 9.5%, 4.1% in pCR versus 9.5% in non-pCR patients. Younger age, clinically positive lymph nodes, G3 tumours, non-pCR and TNBC but not surgery type were independent LRR predictors in multivariate analysis. Among BC subtypes, 5-year cumulative LRR rates were associated with higher risk in non-pCR versus pCR patients, which was significant for HR+/HER2- (5.9% vs 3.9%; HR = 2.32 [95%CI 1.22-4.43]; p = 0.011); HR-/HER2+ (14.8% vs 3.1%; HR = 4.26 [94%CI 2.35-7.71]; p < 0.001) and TNBC (18.5% vs 4.2%; HR = 4.10 [95%CI 2.88-5.82]; p < 0.001) but not for HR+/HER2+ (8.1% vs 4.8%; HR = 1.56 [95%CI 0.85-2.85]; p = 0.150). Within non-pCR subgroup, LRR risk was higher for HR-/HER2+ and TNBC vs HR+/HER2- (HR = 2.05 [95%CI 1.54-2.73]; p < 0.001 and HR = 2.77 [95%CI 2.27-3.39]; p < 0.001, respectively).

CONCLUSIONS

This pooled analysis demonstrated that young age, node-positive and G3 tumours, as well as TNBC, and non-pCR significantly increased the risk of LRR after NACT. Hence, there is a clear need to investigate better multimodality therapies in the post-neoadjuvant setting for high-risk patients.

Successful Immediate Staged Breast Reconstruction with Intermediary Autologous Lipotransfer in Irradiated Patients

As indications for radiotherapy in mastectomized patients grow, the need for greater reconstructive options is critical. Preliminary research suggests an ameliorating impact of lipotransfer on irradiated patients with expander-to-implant reconstruction. Herein, we present our technique using lipotransfer during the expansion stage to facilitate implant placement.

Prognostic impact of repeat sentinel lymph node biopsy in patients with ipsilateral breast tumour recurrence

BACKGROUND

Ipsilateral breast tumour recurrence (IBTR) has an unfavourable prognosis, with a significant subsequent risk of distant recurrence. Repeat sentinel lymph node biopsy (rSLNB) has recently been demonstrated to be technically feasible and useful in tailoring adjuvant treatment plans in patients with IBTR. The prognostic impact of rSLNB in patients with IBTR remains unclear. This study analysed the risk of distant recurrence after IBTR, and evaluated the prognostic impact of rSLNB and other patient and tumour characteristics on distant recurrence-free survival.

METHODS

Data were obtained from the SNARB (Sentinel Node and Recurrent Breast Cancer) study. Cox proportional hazards analyses were performed to assess the prognostic effect of tumour, patient and treatment factors on distant recurrence-free survival.

RESULTS

Of the 515 included patients, 230 (44·7 per cent) had a tumour-negative rSLNB and 46 (8·9 per cent) a tumour-positive rSLNB. In 239 patients (46·4 per cent) the rSLNB procedure was unsuccessful. After a median follow-up of 5·1 years, 115 patients (22·3 per cent) had developed a recurrence. The overall 5-year distant recurrence-free survival rate was 84·2 (95 per cent c.i. 80·7 to 87·7) per cent. An interval of less than 2 years between primary breast cancer treatment and ipsilateral recurrence (P = 0·018), triple-negative IBTR (P = 0·045) and absence of adjuvant chemotherapy after IBTR (P = 0·010) were independently associated with poor distant recurrence-free survival. The association between the outcome of rSLNB and distant recurrence-free survival was not statistically significant (P = 0·682).

CONCLUSION

The outcome of rSLNB is not an important prognostic factor for distant recurrence, and its value as a staging tool in patients with IBTR seems disputable.

Effect of postmastectomy radiotherapy on triple-negative breast cancer with T1-2 and 1-3 positive axillary lymph nodes: a population-based study using the SEER 18 database

There is consensus on the routine use of postmastectomy radiotherapy (PMRT) in patients with four or more positive axillary lymph nodes. However, the benefits of PMRT in patients with T1-2 and 1-3 involved lymph nodes still remain controversial. Data from the Surveillance, Epidemiology, and End Results Program (SEER) of the United States between 2010 and 2012 were used to analyze the outcomes of 675 triple-negative breast cancer (TNBC) patients with T1-2 and 1-3 lymph nodes involved. Those patients were subdivided into radiotherapy (RT) (312) and no-RT groups (363). After a median follow-up time of 37 months, Kaplan-Meier analysis showed that PMRT significantly improved overall survival (OS) but not breast cancer-specific survival (BCSS) in the total cohort of 675 patients (P=0.033 and P=0.063). And it was demonstrated that PMRT were independently associated with increased OS according to univariate and multivariate analyses. However, no significant differences in BCSS or OS were observed between the groups stratified by the number of positive lymph nodes. In conclusion, PMRT significantly improved OS for TNBC patients with T1-2 and 1-3 lymph nodes involved. Additional prospective studies are needed to provide a stronger evidence base for choosing patients for PMRT.

Individualized Prediction of Survival Benefit from Postmastectomy Radiotherapy for Patients with Breast Cancer with One to Three Positive Axillary Lymph Nodes

PURPOSE

There still exist some arguments regarding the use of postmastectomy radiotherapy (PMRT) for patients with breast cancer carrying one to three positive axillary lymph nodes considering the heterogeneity of this cohort. Here, we developed a prognostic nomogram to estimate the probability of long-term outcome in patients receiving or not receiving PMRT in order to assist in making individually locoregional treatment decisions for this particular cohort.

METHODS

Altogether, 20,336 women, aged 18 to 80 years, diagnosed with breast cancer, and carrying one to three positive nodes were identified in the Surveillance, Epidemiology, and End Results (SEER) database. We applied multivariant Cox hazard model to determine the impact of covariates on disease-specific survival (DSS) and overall survival (OS). Then, the nomogram was built accordingly. Internal and external validations were performed to examine the accuracy of nomograms.

RESULTS

Age of diagnosis, tumor grade, size, estrogen and progesterone receptor status, and number of positive nodes were independent factors of DSS and OS in the multivariate analysis. Incorporating these factors into the constructed nomogram showed high accuracy when predicting 5- and 10-year survival, with internally and externally bootstrap-corrected concordance indexes in the range of 0.6 to 0.8.

CONCLUSION

Besides the number of involved nodes, extra variables existed as predictors of survival outcomes in this cohort; therefore, the recommendation of PMRT or no PMRT requires comprehensive consideration. This clinically validated nomogram provided a useful tool that could aid decision making by estimating DSS and OS benefits from PMRT, useful in predicting 5- and 10-year DSS and OS for patients with one to three positive nodes after mastectomy.

IMPLICATIONS FOR PRACTICE

This study evaluated population-based data to identify prognostic factors associated with patients with breast cancer with one to three lymph nodes and help clinicians to weigh the benefit of postmastectomy radiotherapy (PMRT). Surveillance, Epidemiology, and End Results (SEER) data were used to develop a prognostic nomogram to predict the likelihood of long-term survival with and without PMRT in order to optimize the individual locoregional control strategy for this particular cohort. This clinically validated nomogram provides a useful tool to predict 5- and 10-year disease-specific survival and overall survival for patients with one to three positive nodes and can aid tailored clinical decision making by estimating predicted benefit from PMRT.

Comparison of long-term results between radiotherapy after breast-conserving surgery and postmastectomy radiotherapy in stage T1-2N1M0 breast cancer

Purpose

Postoperative radiotherapy (RT) can improve survival for T1-2N1 breast cancer. However, there exists a concern whether BCS plus RT has the same or a superior therapeutic effect as that of mastectomy. In this study, we aimed to compare the long-term results between RT after BCS and postmastectomy RT in stage T1-2N1M0 breast cancer.

Patients and Methods

Totally 1816 pathological stage T1-2N1M0 breast cancer patients were analyzed. The propensity score matching (PSM) method was used to select 196 pairs of patients between BCS and mastectomy receiving postoperative RT. Five-year locoregional relapse (LRR), locoregional relapse-free survival (LRFS), distant metastasis (DM), distant metastasis-free survival (DMFS), disease-free survival (DFS), breast cancer-specific survival (BCSS) were analyzed as endpoints.

Results

In the whole group, significant differences were observed in all endpoints (P<0.05) between the no-RT and RT groups. For patients receiving mastectomy, DM, DMFS, DFS and BCSS rates had no differences between the two groups. For patients without RT in the multivariable analysis, the molecular subtype was associated with each endpoint (P<0.05). Age, primary tumor site, tumor size, and LVI status were significantly associated with DM. The analysis of 196 pairs of patients selected by PSM showed that BCS plus RT resulted in a significantly lower 5-year DM rate (P=0.015) and superior survival in terms of the 5-year DMFS (P=0.046), DFS (P=0.049) and BCSS (P=0.024) compared with mastectomy.

Conclusions

Postoperative radiotherapy remarkably improved survival in T1-2N1M0 breast cancer but not in the mastectomy subgroup, except for LRR and LRFS. Patients with BCS plus RT had better survival compared with those with postmastectomy radiation in terms of DM, DMFS, DFS and BCSS.

The Impact of a Postmastectomy Chest Wall Scar Boost on Local Recurrence-free Survival in High-risk Patients

INTRODUCTION

A scar boost following postmastectomy radiation to a total dose of > 50 Gy can be considered in cases of invasive breast cancer with high-risk features including advanced tumor stage, lymphovascular space invasion (LVSI), and positive margins. The purpose of this study was to determine the impact of a scar boost on 5-year local recurrence-free survival (LRFS).

MATERIALS AND METHODS

We retrospectively analyzed 140 patients with invasive breast cancer treated with mastectomy and postmastectomy radiation at a single institution between 2007 and 2016. Patients received 50 to 50.4 Gy to the chest wall and the majority of scar boosts were 9 to 10 Gy. LRFS was examined using the Kaplan-Meier method and univariable Cox regression.

RESULTS

A total of 140 patients met inclusion criteria with a median follow-up time of 48 months. Ninety-four (67.1%) patients did receive a scar boost and 46 (32.9%) patients did not. On subset analysis of patients with LVSI or positive margins, 5-year LRFS was 79.3% in patients treated with scar boost compared with 71.1% in patients without a scar boost (P = .537). In patients with T3 or T4 disease, 5-year LRFS was 80.9% in those who received scar boost and 71.6% in patients who did not (P = .967). The use of a scar boost was not associated with a significant improvement in LRFS on Cox regression (hazard ratio, 0.83; 95% confidence interval, 0.37-1.84; P = .654).

CONCLUSION

Use of a scar boost following postmastectomy radiation decreased the absolute percentages of local recurrences in patients with high-risk features; however, this did not translate into a statistically significant benefit.

Post Mastectomy Radiation for Stage II Breast Cancer Patients with T1/T2 Lesions

Objective

Post mastectomy radiation (PMR) is usually recommended for T3 or N2 breast cancer (BC). The role of PMR for stage II BC with T1/T2 lesions remains controversial. The aim of this study was to assess the role of PMR in this subgroup of patients.

Materials and Methods

A retrospective analysis of a prospectively collected database of all stage II BC patients treated with mastectomy at our institution between the years 2005-2008 was performed. Demographics, disease-free survival rates were compared between the patients receiving radiation vs. those who were not irradiated.

Results

Eighty-two patients underwent mastectomies for stage II disease with a T1/T2 lesion. Twenty-two of those (27%) received PMR. Loco regional recurrence (LRR) occurred only in the non -irradiated (NR) group. A Kaplan Meier analysis of time to LRR in the NR group was performed. Mean time to local failure was 78.9 months, 6% at 3 years and 13% at 5 years. The time to LRR was significantly lower in the estrogen receptor (ER) negative group compared to the ER positive group (64 vs. 82 months, p=0.029). LRR free rate at 5 years was 100% in low grade tumors vs. 53% in high grade tumors, (p=0.001). In a Cox regression multivariate analysis none of those factors maintained significance.

Conclusion

ER negative status, high grade and node negativity were associated with LRR. A prospective trial randomizing stage II BC patients with T1/T2 lesions, negative hormone receptors and high-grade tumors to PMR following mastectomy arm vs. no radiation arm is recommended.

Local and regional recurrence following mastectomy in breast cancer patients with 1-3 positive nodes: implications for postmastectomy radiotherapy volume

PURPOSE

To determine the necessity of postmastectomy radiotherapy (PMRT) and which regions would be at risk for recurrence, we evaluated local and regional recurrence in breast cancer patients with 1-3 positive nodes and a tumor size of <5 cm.

MATERIALS AND METHODS

We retrospectively analyzed data of 133 female breast cancer patients with 1-3 positive nodes, and a tumor size of <5 cm who were treated with mastectomy followed by adjuvant systemic therapy between 2007 and 2016. The median follow-up period was 57 months (range, 12 to 115 months). Most patients (82.7%) were treated with axillary lymph node dissection. Adjuvant chemotherapy, endocrine therapy, and trastuzumab therapy were administered to 124 patients (93.2%), 112 (84.2%), and 33 (24.8%), respectively. The most common chemotherapy regimen was anthracycline and cyclophosphamide followed by taxane (71.4%).

RESULTS

Three patients (2.3%), 8 (6.0%), and 12 (9.0%) experienced local, regional, and distant failures, respectively. The 5-year cumulative risk of local recurrence, regional recurrence, distant metastasis, and disease-free survival was 3.1%, 8.0%, 11.7%, and 83.4%, respectively. There were no statistically significant clinicopathologic factors associated with local recurrence. Lymphovascular invasion (univariate p = 0.015 and multivariate p = 0.054) was associated with an increased risk of regional recurrence.

CONCLUSION

Our study showed a very low local recurrence in patients with 1-3 positive nodes and tumor size of <5 cm who were treated with mastectomy and modern adjuvant systemic treatment. The PMRT volume need to be tailored for each patient's given risk for local and regional recurrence, and possible radiation-related toxicities.

Nomogram Predicting Locoregional Recurrence to Assist Decision-Making of Postmastectomy Radiation Therapy in Patients With T1-2N1 Breast Cancer

PURPOSE

Postmastectomy radiation therapy (PMRT) had heterogeneous effects on survival outcome of patients with T1-2N1 breast cancer. A reliable model to estimate individuals' risk of locoregional recurrence (LRR) and the potential benefit derived from PMRT is needed.

METHODS AND MATERIALS

We retrospectively analyzed 1141 patients with T1-2N1 breast cancer who underwent mastectomy between January 2001 and December 2012. Based on the Fine and Gray competing risks regression in 623 unirradiated patients, a nomogram predicting LRR was conducted for risk quantification. Decision tree analysis was performed for patient grouping. The impact of PMRT was evaluated among 3 subgroups.

RESULTS

With a median follow-up of 74.9 months, the 5-year cumulative incidence of LRR, distant recurrence (DR) and breast cancer mortality (BCM) were 3.9%, 8.8%, and 6.0%, respectively, for the entire cohort. Based on nomogram scores, patients were classified into 3 risk groups in decision tree analysis. In the high-risk group, PMRT was found to be associated with a 12.7% risk reduction of 5-year LRR, 9.2% risk reduction of 5-year DR, and 7.0% risk reduction of 5-year BCM, whereas it was not significantly associated with LRR, DR, or BCM in low- and intermediate-risk groups.

CONCLUSIONS

The nomogram performed individualized risk quantification of LRR in patients with T1-2N1 breast cancer. A newly identified patient subgroup with high risk of LRR were found to derive survival benefit from PMRT.

Axillary Lymph Node Dissection Does Not Improve Post-mastectomy Overall or Disease-Free Survival among Breast Cancer Patients with 1-3 Positive Nodes

Purpose

Axillary lymph node dissection (ALND) may be avoidable for breast cancer patients with 1-2 positive lymph nodes (LN) after breast-conserving therapy. However, the effects of ALND after mastectomy remain unclear because radiation is not routinely used. Herein, we compared the benefits of post-mastectomy ALND versus sentinel node biopsy (SNB) alone for breast cancer patients with 1-3 metastatic LNs.

Materials and Methods

A total of 1,697 patients with pN1 disease who underwent mastectomy during 2000-2015 were identified from an institutional database. Outcomes were compared using the inverse probability of treatment weighted method.

Results

Patients who underwent SNB tended to have smaller tumors, a lower histology grade, a lower number of positive LNs, and better immunohistochemical findings. After correcting all confounding factors regarding patient, tumor, and adjuvant treatment, the SNB and ALND groups did not differ in terms of overall survival (OS) and disease-free survival (DFS), distant metastasis and locoregional recurrence. The 10-year DFS and OS rates were 83% and 84%, respectively, during a median follow-up period of 93 months.

Conclusion

ALND did not improve post-mastectomy survival outcomes among patients with N1 breast cancer, even after adjusting for all histopathologic and treatment-related factors.

Management of In-Breast Tumor Recurrence

The management of isolated in-breast tumor recurrence is complex, requiring careful consideration of prior local therapies to plan future multimodality treatment. Options for surgical management have evolved from standard salvage mastectomy with axillary clearance and now include repeat breast conservation with axillary staging in select patients. Reattempting sentinel lymph node biopsy may avoid the morbidity of extensive axillary surgery and has been shown to be feasible in clinically node-negative patients with oncologically safe outcomes. In the adjuvant setting, partial breast irradiation has emerged as a valuable means to improve local control rates with limited associated toxicity and acceptable overall cosmesis. Furthermore, results from prospective trials are now available to support the use of chemotherapy in hormone-receptor negative subgroups, which is associated with improvements in long-term, disease-free, and overall survival.

Integrating Radiosensitivity and Immune Gene Signatures for Predicting Benefit of Radiotherapy in Breast Cancer

Purpose: Breast cancer is a heterogeneous disease and not all patients respond equally to adjuvant radiotherapy. Predictive biomarkers are needed to select patients who will benefit from the treatment and spare others the toxicity and burden of radiation.Experimental Design: We first trained and tested an intrinsic radiosensitivity gene signature to predict local recurrence after radiotherapy in three cohorts of 948 patients. Next, we developed an antigen processing and presentation-based immune signature by maximizing the treatment interaction effect in 129 patients. To test their predictive value, we matched patients treated with or without radiotherapy in an independent validation cohort for clinicopathologic factors including age, ER status, HER2 status, stage, hormone-therapy, chemotherapy, and surgery. Disease-specific survival (DSS) was the primary endpoint.Results: Our validation cohort consisted of 1,439 patients. After matching and stratification by the radiosensitivity signature, patients who received radiotherapy had better DSS than patients who did not in the radiation-sensitive group [hazard ratio (HR), 0.68; P = 0.059; n = 322], whereas a reverse trend was observed in the radiation-resistant group (HR, 1.53; P = 0.059; n = 202). Similarly, patients treated with radiotherapy had significantly better DSS in the immune-effective group (HR, 0.46; P = 0.0076; n = 180), with no difference in DSS in the immune-defective group (HR, 1.27; P = 0.16; n = 348). Both signatures were predictive of radiotherapy benefit (P _interaction = 0.007 and 0.005). Integration of radiosensitivity and immune signatures further stratified patients into three groups with differential outcomes for those treated with or without radiotherapy (P _interaction = 0.003).Conclusions: The proposed signatures have the potential to select patients who are most likely to benefit from radiotherapy. Clin Cancer Res; 24(19); 4754-62. ©2018 AACR.

Impact of postmastectomy radiation therapy in T1-2 breast cancer patients with 1-3 positive axillary lymph nodes

The effect of postmastectomy radiotherapy (PMRT) on T1-2 breast cancer patients with 1-3 positive axillary lymph nodes is controversial up to now. The purpose of this study was to evaluate the impact of postmastectomy radiotherapy for these patients. The prognostic factor effecting locoregional free-survival (LRFS) was also analyzed. In the retrospective clinical data of 1674 eligible patients, survival analysis was performed using the method of Kaplan-Meier and the log-rank test. Cox regression analysis was applied to identify the significant prognostic factors. We found PMRT increased 5-year LRFS (p=0.003), but could not improve 5-year disease-free survival or overall survival statistically. For patients without PMRT, multivariate analysis revealed that age, lymph node ratio and molecule subtype were risk factors effecting LRFS. To further analyze the role of PMRT, we grouped all the patients into low risk group (0 or 1 risk factor) and high risk group (2 or 3 risk factors) depending on these risk factors. We found that in low-risk group, PMRT increased only 5-year LRFS (p=0.012). However, in high-risk group, PMRT increased both 5-year LRFS (p=0.005) and 5-year disease-free survival (p=0.033), but could not improve 5-year overall survival statistically. Thus, these data provide the evidence that PMRT could improve LRFS for T1-2 breast cancer patients with 1-3 positive axillary lymph nodes. Additionally, PMRT could improve LRFS and disease-free survival for high risk patients. Age, lymph node ratio and molecule subtype were high risk factors effecting LRFS in our study.

Chronological Improvement in Survival of Patients with Breast Cancer: A Large-Scale, Single-Center Study

Purpose

This study aimed to chronologically evaluate survival of patients with breast cancer in Korea and investigate the observed changes during the last 20 years. We also sought to determine factors that may influence outcomes and changes in the duration of survival over time.

Methods

We retrospectively analyzed a total of 10,988 patients with breast cancer who were treated at our institution between January 1993 and December 2008. We divided the study period into three periods (P1, 1993–1997; P2, 1998–2002; and P3, 2003–2008). We retrospectively reviewed the collected data from the Asan database, including age at diagnosis, clinical manifestations, pathology report, surgical methods, types of adjuvant treatment modalities, type of recurrence, and follow-up period.

Results

At a median follow-up of 8.2 years, we observed that survival outcomes have improved recently. The 5-year breast cancer-specific survival (BCSS) rate also increased from 82.8% in P1 to 92.6% in P3 (p<0.001). The survival rate in patients with tumors at each stage increased in similar patterns in all patients, and, remarkably, there was a significant survival improvement in patients with stage III breast cancer (P1 vs. P3: 5-year BCSS, 57.4% vs. 80.0%, p<0.001). The time period was a significant prognostic factor in multivariate analysis (P1 vs. P2: hazard ratio [HR], 0.83, p=0.035; P1 vs. P3: HR, 0.75, p=0.015).

Conclusion

The study results suggest an improvement in breast cancer survival in Korea, which is consistent with the development of treatments and early detection.

Should all breast cancer patients with four or more positive lymph nodes who underwent modified radical mastectomy be treated with postoperative radiotherapy? A population-based study

Postmastectomy radiotherapy (PMRT) has become a standard adjuvant postoperative therapy for breast cancer patients with four or more positive lymph nodes. However, some studies have demonstrated that some subgroups of the breast cancer patients with four or more positive lymph nodes did not benefit substantially from PMRT. Therefore, it is of great necessity to identify whether all breast cancer patients with four or more positive lymph nodes who underwent modified radical mastectomy be treated with PMRT. In our study, we first established a prognostic model using the Surveillance Epidemiology and End Results (SEER) database between 1998 and 2001. Univariate and multivariate Cox models were used to assess the prognostic factors, and five risk factors individually associated with prognosis including AJCC stage, AJCC T, Grade, ER status, PR status. Prognostic index of PMRT were defined as the number of risk factor (NRF). The NRF scores correlated well with overall survival of PMRT even if the patients were in the sub-poor prognosis group. Then the prognostic model was validated using the SEER database between 2006 and 2009, and the same results were obtained. In conclusion, different from others studies, our study demonstrated that all patients with four or more positive lymph nodes after modified radical mastectomy need to be treated with PMRT ever if the patients belonged to AJCC T4 in a poor prognosis group.

Postmastectomy Radiation Therapy in Women with T1-T2 Tumors and 1 to 3 Positive Lymph Nodes: Analysis of the Breast International Group 02-98 Trial

PURPOSE

To analyze the impact of postmastectomy radiation therapy (PMRT) for patients with T1-T2 tumors and 1 to 3 positive lymph nodes enrolled on the Breast International Group (BIG) 02-98 trial.

METHODS AND MATERIALS

The BIG 02-98 trial randomized patients to receive adjuvant anthracycline with or without taxane chemotherapy. Delivery of PMRT was nonrandomized and performed according to institutional preferences. The present analysis was performed on participants with T1-T2 breast cancer and 1 to 3 positive lymph nodes who had undergone mastectomy and axillary nodal dissection. The primary objective of the present study was to examine the effect of PMRT on risk of locoregional recurrence (LRR), breast cancer-specific survival, and overall survival.

RESULTS

We identified 684 patients who met the inclusion criteria and were included in the analysis, of whom 337 (49%) had received PMRT. At 10 years, LRR risk was 2.5% in the PMRT group and 6.5% in the no-PMRT group (hazard ratio 0.29, 95% confidence interval 0.12-0.73; P = .005). Lower LRR after PMRT was noted for patients randomized to receive adjuvant chemotherapy with no taxane (10-year LRR: 3.4% vs 9.1%; P = .02). No significant differences in breast cancer-specific survival (84.3% vs 83.9%) or overall survival (81.7% vs 78.3%) were observed according to receipt of PMRT.

CONCLUSION

Our analysis of the BIG 02-98 trial shows excellent outcomes in women with T1-T2 tumors and 1 to 3 positive lymph nodes found in axillary dissection. Although PMRT improved LRR in this cohort, the number of events remained low at 10 years. In all groups, 10-year rates of LRR were relatively low compared with historical studies. As such, the use of PMRT in women with 1 to 3 positive nodes should be tailored to individual patient risks.

Can Axillary and Supraclavicular Radiotherapy be Avoided after Breast-Conserving Surgery and Axillary Dissection in Women with Multiple Involved Axillary Nodes?: Experience at the European Institute of Oncology

Aims and background

Although some guidelines recommend adjuvant radiotherapy (RT) to the axilla and supraclavicular nodes if 4 or more axillary nodes are involved, the current practice at our Institute is not to irradiate the axilla but to perform complete axillary dissection in which all 3 Berg levels are removed. We performed a retrospective analysis of patients with 4 or more axillary nodes involved and sufficient follow-up to provide indications as to whether our current treatment is adequate.

Methods

We retrospectively analyzed 287 T1–T3 patients with a median follow-up of 5 years and 4 or more involved nodes treated by quadrantectomy and breast RT but no axillary RT; supraclavicular RT was given only when prognostic factors were unfavorable.

Results

A total of 170 (59.2%) patients did not receive supraclavicular RT, while 117 (40.8%) patients received supraclavicular irradiation. No patient received axillary RT. After a median follow-up of 5 years (range, 4–105 months), 4.7% had died and 13.5% had developed distant metastases in the no supraclavicular RT group, compared to 12.0% dead (P = 0.028 log rank) and 24.8% (P = 0.201 log rank) in the supraclavicular RT group. No patients with supraclavicular RT developed supraclavicular metastases compared to 4 in the no supraclavicular RT group. There were no axillary recurrences.

Conclusions

Complete axillary dissection appears adequate treatment in patients with 4 or more involved nodes. The low breast recurrence rate also suggests that breast conservation is adequate treatment in such patients. Supraclavicular RT appears to reduce the number of supraclavicular metastases but confers no survival advantage. Although a small number of cases were examined in this retrospective single-center series, all received highly uniform treatment.

A prognostic score model to determine which breast cancer patients with 1-3 positive lymph nodes after modified radical mastectomy should receive radiotherapy

There is no consensus on the indication for postmastectomy radiotherapy (PMRT) in breast cancer patients with one to three positive lymph nodes. To identify patients for whom PMRT may be indicated, we used a prognostic score model with the SEER database to retrospectively analyze 8049 patients with one to three positive lymph nodes who underwent mastectomy with or without PMRT between 2010 and 2013. Kaplan-Meier analysis showed that PMRT patients had better overall survival (OS) than no-PMRT patients (P < 0.001); however, there was no difference in cancer-specific survival (CSS) (P = 0.530). Multivariate analysis with Cox regression showed that grade (P < 0.001), tumor size (P < 0.001), and progesterone receptor status (P < 0.001) were independent prognostic factors for OS. To diminish bias, we used 1:1 propensity score matching analysis and prognosis score model, which revealed that PMRT patients had better OS and CSS than no-PMRT patients (P < 0.001). In a concrete subgroup analysis of PMRT patients, significant improvements in OS were observed in patients scoring 0, 1, or 2. PMRT patients scoring 2 also had improved CSS. The magnitude of the OS and CSS difference with PMRT correlated with the prognostic score (P < 0.001). These results suggest PMRT in breast cancer patients with one to three positive lymph nodes should be based on patient factors, tumor biology, and prognostic score.