Validation of the PREDICT Prognostication Tool in US Patients With Breast Cancer.

BACKGROUND: PREDICT is an online prognostication tool derived from breast cancer registry information on approximately 6,000 women treated in the United Kingdom that estimates the postsurgical treatment benefit of surgery alone, chemotherapy, trastuzumab, endocrine therapy, and/or adjuvant bisphosphonates in early-stage breast cancer. Our aim was to validate the PREDICT algorithm in predicting 5- and 10-year overall survival (OS) probabilities using real-world outcomes among US patients with breast cancer. METHODS: A retrospective study was performed including women diagnosed with unilateral breast cancer in 2004 through 2012. Women with primary unilateral invasive breast cancer were included. Patients with bilateral or metastatic breast cancer, no breast surgery, or missing critical clinical information were excluded. Prognostic scores from PREDICT were calculated and external validity was approached by assessing statistical discrimination through area under time-dependent receiver-operator curves (AUC) and comparing the predicted survival to the observed OS in relevant subgroups. RESULTS: We included 708,652 women, with a median age of 58 years. Most patients were White (85.4%), non-Hispanic (88.4%), and diagnosed with estrogen receptor-positive breast cancer (79.6%). Approximately 50% of patients received adjuvant chemotherapy, 67% received adjuvant endocrine therapy, 60% underwent a partial mastectomy, and 59% had 1 to 5 axillary sentinel nodes removed. Median follow-up time was 97.7 months. The population's 5- and 10-year OS were 89.7% and 78.7%, respectively. Estimated 5- and 10-year median survival with PREDICT were 88.3% and 73.8%, and an AUC of 0.77 and 0.76, respectively. PREDICT performed most poorly in patients with high Charlson-Deyo comorbidity scores (2-3), where PREDICT overestimated OS. Sensitivity analysis by year of diagnosis and HER2 status showed similar results. CONCLUSIONS: In this prognostic study utilizing the National Cancer Database, the PREDICT tool accurately predicted 5- and 10-year OS in a contemporary and diverse population of US patients with nonmetastatic breast cancer.

Adjuvant Therapy in Breast Cancer Patients With Microscopic Residual Disease.

INTRODUCTION: Surgical resection is the gold standard for early-stage breast cancer. Positive surgical margins are associated with poor outcome. Endocrine therapy (ET) is recommended as primary systemic treatment for hormone receptor positive (HR+) breast cancer after surgery. We hypothesized that chemoenocrine therapy (CET) would not be associated with improved survival relative to ET for patients with positive margins. MATERIALS AND METHODS: The National Cancer Database was queried for pathologic stage I HR + HER2-breast cancer patients treated with partial mastectomy and adjuvant whole-breast irradiation between 2004 and 2017. The adjuvant treatment approaches to positive surgical margins were investigated and compared. Overall survival was compared between systemic treatment groups using multivariable cox proportional hazards regression. RESULTS: Among 228,453 patients, a positive surgical margin (microscopic residual disease, R1) was identified in 3561 (1.6%) patients. Compared with complete resections, positive margin was associated with inferior overall survival (hazard ratio [HR] = 1.276, P = 0.003). Among the R1 patients, 78.7% received ET only, 11.7% received CET, 1.2% received chemotherapy only, and 8.5% received no systemic therapy. After controlling for patient, facility, and tumor characteristics, ET provided greatest survival benefit (relative to no therapy, HR = 0.378, P < 0.001) followed by CET (HR = 0.446, P = 0.020). Compared with ET alone, CET is not associated with additional overall survival benefit (HR = 1.179, P = 0.595). CONCLUSIONS: CET appeared not to be associated with an improved overall survival in early stage HR + HER2-breast cancer with microscopic residual disease relative to ET. Positive surgical margins therefore are probably not a relevant clinical factor for adjuvant chemotherapy decision-making.

Mouse-INtraDuctal (MIND): an in vivo model for studying the underlying mechanisms of DCIS malignancy.

Due to widespread adoption of screening mammography, there has been a significant increase in new diagnoses of ductal carcinoma in situ (DCIS). However, DCIS prognosis remains unclear. To address this gap, we developed an in vivo model, Mouse-INtraDuctal (MIND), in which patient-derived DCIS epithelial cells are injected intraductally and allowed to progress naturally in mice. Similar to human DCIS, the cancer cells formed in situ lesions inside the mouse mammary ducts and mimicked all histologic subtypes including micropapillary, papillary, cribriform, solid, and comedo. Among 37 patient samples injected into 202 xenografts, at median duration of 9 months, 20 samples (54%) injected into 95 xenografts showed in vivo invasive progression, while 17 (46%) samples injected into 107 xenografts remained non-invasive. Among the 20 samples that showed invasive progression, nine samples injected into 54 xenografts exhibited a mixed pattern in which some xenografts showed invasive progression while others remained non-invasive. Among the clinically relevant biomarkers, only elevated progesterone receptor expression in patient DCIS and the extent of in vivo growth in xenografts predicted an invasive outcome. The Tempus XT assay was used on 16 patient DCIS formalin-fixed, paraffin-embedded sections including eight DCISs that showed invasive progression, five DCISs that remained non-invasive, and three DCISs that showed a mixed pattern in the xenografts. Analysis of the frequency of cancer-related pathogenic mutations among the groups showed no significant differences (KW: p > 0.05). There were also no differences in the frequency of high, moderate, or low severity mutations (KW; p > 0.05). These results suggest that genetic changes in the DCIS are not the primary driver for the development of invasive disease. © 2021 The Authors. The Journal of Pathology published by John Wiley & Sons Ltd on behalf of The Pathological Society of Great Britain and Ireland.

A comparison of local therapy alone with local plus systemic therapy for stage I pT1aN0M0 HER2+ breast cancer: A National Cancer Database analysis.

BACKGROUND: Small invasive breast cancers (BCs) with tumor sizes ≤5 mm (T1a) are associated with an excellent prognosis without systemic therapy. Although HER2 overexpression (HER2+) is associated with a higher risk of recurrence and poorer clinical outcomes, in the absence of HER2 directed therapy, it remains unclear whether adjuvant systemic therapy is necessary in node-negative patients diagnosed with HER2+ invasive BCs ≤5 mm (pT1aN0M0). METHODS: The National Cancer Database was searched to identify patients diagnosed with HER2+ pT1aN0M0 BCs from 2004 to 2017. The cohort was stratified by treatment status: local therapy alone or local plus adjuvant systemic therapy. A 1:1 propensity match was performed. Overall survival (OS) was analyzed using stratified multivariable Cox proportional hazards regression analyses. RESULTS: Of the 8948 patients found, 4026 (45.0%) underwent surgery alone, and 4922 (55.0%) received surgery plus systemic therapy. Patients with either moderately differentiated (odds ratio [OR], 2.053; P < .001) or poorly/undifferentiated tumors (OR, 3.780; P < .001) or with the presence of lymphovascular invasion (OR, 3.351; P < .001) were more likely to have received systemic therapy. Propensity matching generated 1162 pairs of patients who were hormone receptor positive (HR+) and 748 pairs who were hormone receptor negative (HR-). Propensity matching effectively reduced selection bias between study groups. In the matched cohort, the addition of systemic therapy was not associated with superior OS (hazard ratio for HR+, 1.613; P = .107, and hazard ratio for HR- 1.319; P = .369) compared with patients who received local therapy alone. CONCLUSIONS: In pT1aN0M0 HER2+ BC, the addition of adjuvant systemic therapy after surgical excision was not associated with improved OS compared with local therapy alone.

The clinical impact of MRI on surgical planning for patients with in-breast tumor recurrence.

OBJECTIVE: The objective of this study was to evaluate the clinical utility of breast MRI for patients with known in-breast tumor recurrence (IBTR). The aim was to determine if the addition of breast MRI altered surgical approach or multidisciplinary management. Previous studies have focused on using breast MRI for surgical planning for index breast cancers (BC) or detecting IBTR. However, the clinical impact of obtaining MRI in the setting of known IBTR has not been evaluated. METHODS: A single-institution retrospective chart review was performed to compare surgical approach and multidisciplinary management for patients diagnosed with isolated IBTR who did and did not undergo breast MRI following IBTR diagnosis. RESULTS: IBTR was identified in 69 patients, 46% of whom underwent MRI. There was no difference in the operative approach (p = 0.14) for IBTR patients who did and did not undergo breast MRI Additionally, there was no difference in multidisciplinary care, treatment order, metastatic disease identification, or mortality between cohorts. A relatively small subgroup of patients (n = 3) required change in surgical plan based on MRI results. Patients proceeding with surgery first who also underwent breast MRI experienced a significantly longer time to surgical intervention (p = 0.03). CONCLUSION: Breast MRI following IBTR diagnosis infrequently impacted clinical management, including surgical approach and multidisciplinary care. MRI for local disease assessment at the time of IBTR should be used selectively based on clinical concern.

Guideline-Consistent Treatment for Inflammatory Breast Cancer Provides Associated Survival Benefit Independent of Age.

BACKGROUND: Guideline-consistent treatment (GCT) for inflammatory breast cancer (IBC) includes neoadjuvant chemotherapy (NAC), modified radical mastectomy (MRM), and radiation. We hypothesized that younger patients more frequently receive GCT, resulting in survival differences. METHODS: Using the National Cancer Database (2004-2018), female patients with unilateral IBC (by histology code and clinical stage T4d) were stratified by age (< 50, 50-65, > 65 years). Factors associated with NAC, MRM, radiation, and "GCT" (defined as all three treatments) were identified using multivariable logistic regression. Multivariable Cox proportional hazards regression identified predictors of overall survival. RESULTS: Of 3278 IBC patients, 30% were younger than 50 years, 44% were 50-65 years of age, and 26% were older than 65 years. The youngest group comprised the greatest proportion of non-White patients ([35%] vs. [29%] age 50-65 years and [23%] age > 65 years, p < 0.001) and was most often treated at academic facilities ([33%] vs. [28%] age 50-65 years; and [23%] age > 65, p < 0.001). Patients older than 65 years received NAC, MRM, and radiation less frequently, and only 35% underwent GCT (vs. [57%] age 50-65 years and [52%] age < 50 years; p < 0.001). On multivariable logistic regression, age older than 65 years independently predicted omission of NAC (odds ratio [OR], 0.36), MRM (OR, 0.56), and radiation (OR, 0.56) (all p < 0.001), and patients older than 65 years also were less likely to undergo GCT than patients 50-65 years of age (OR, 0.65; p = 0.001). GCT was associated with superior overall survival in all three age groups ([hazard ratio {HR}, 0.61] age < 50 years, [HR, 0.62] age 50-65 years, [HR, 0.53] age > 65 years; all p < 0.001). CONCLUSION: Advanced age alone should not limit receipt of GCT for IBC. Multimodal care should be performed for IBC patients of all ages to improve oncologic outcomes for this aggressive breast cancer subtype.

Rethinking Routine Surgical Excision for all Radial Sclerosing Lesions of the Breast.

INTRODUCTION: The need for routine surgical excision of a radial sclerosing lesions (RSL) of the breast identified on percutaneous biopsy remains controversial, as contemporary upgrade rates are lower than historically cited. MATERIALS AND METHODS: A prospectively-maintained database of high-risk breast biopsies undergoing multidisciplinary review at a single institution was queried to identify cases of RSL from 2/2015 to 11/2020. Demographic, radiologic, and pathologic variables were summarized using frequencies and analyzed in association with RSL excision status using mixed-effects logistic regression or Fisher's exact tests. RESULTS: 217 RSL were identified, diagnosed at a mean age of 57 y. The median imaging size was 1.3 cm and the majority had estimated >50% of the target removed by core needle biopsy. 32.3% underwent surgical excision of the RSL biopsy site and 2/70 (2.9%) upgraded to ductal carcinoma in situ (DCIS) on final surgical pathology. Upgrade was significantly higher for atypical RSL (P = 0.02). None of the RSL (n = 60) without atypia who had undergone excision were upgraded. For those omitting surgical excision, there was no subsequent breast cancer diagnosis at the RSL site over a mean follow-up of 23 mo. CONCLUSIONS: Surgical excision may be omitted for RSL without atypia as this group has 0% risk of upgrade after multidisciplinary review.

Is bioimpedance spectroscopy a useful tool for objectively assessing lymphovenous bypass surgical outcomes in breast cancer-related lymphedema?

PURPOSE: We sought to determine if bioimpedance spectroscopy (BIS) measurements can accurately assess changes in breast cancer-related lymphedema (BCRL) in patients undergoing lymphovenous bypass (LVB). METHODS: Patients undergoing LVB for BCRL refractory to conservative treatment from 1/2015 to 12/2018 were identified from an IRB-approved prospectively maintained database at a single institution. All breast cancer patients were assessed with baseline BIS measurements prior to any oncologic surgery and serial BIS during follow-up office visits including before and after LVB. Clinicopathologic information, LVB operative details, and pre- and post-LVB operative BIS measurements were collected. Analysis focused on clinically significant BIS change, defined as two standard deviations (SD), and comparing LVB anastomosis to BIS changes. RESULTS: During the study timeframe, nine patients underwent LVB for treatment of BCRL. The majority (78%) received radiation, taxane chemotherapy, and underwent axillary dissection. An average of 5.6 LVB anastomoses were performed per patient. The average change in BIS following LVB was a 3SD reduction, indicating a clinically significant change. This improvement was stable over time, with persistent 2SD reduction at 22 months postoperatively. The number of LVB anastomoses performed did not significantly correlate with the degree of BIS change. CONCLUSIONS: This is the first study to utilize BIS measurements to assess response to LVB surgical intervention for BCRL. BIS measurements demonstrated clinically significant improvement after LVB, providing objective evidence in support of this surgical treatment for BCRL. BIS changes should be reported as key objective data in future studies assessing BCRL interventions, including response to LVB.

Is axillary imaging for invasive lobular carcinoma accurate in determining clinical node staging?

PURPOSE: Preoperative evaluation of clinical N-stage (cN) is difficult in breast cancer patients with invasive lobular carcinoma (ILC). Our goal was to assess the predictive value of axillary imaging in ILC by comparing imaging cN and pathologic N-stage (pN). METHODS: A single-institution retrospective review was performed for newly diagnosed stage I-III ILC patients undergoing preoperative breast imaging from 2011 to 2016. Clinicopathologic factors; mammogram, MRI, and ultrasound findings; and surgical pathology data were reviewed. Sub-analysis for pN2-N3 patients was performed to determine imaging sensitivity for patients with a larger nodal disease burden. Statistical analysis included sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) of each imaging modality. RESULTS: Of the total 349 patients included, 70.5% were cN0, and 62% were pN0 (p = 0.03). For all patients, mammogram sensitivity was 7%, specificity 97%, PPV 50%, NPV 72%; ultrasound sensitivity was 26%, specificity 86%, PPV 52%, NPV 67%; MRI sensitivity was 7%, specificity 98%, PPV 80%, NPV 51%. For pN2/N3 patients, 38% were identified as cN0. Mammogram sensitivity was 10%; ultrasound 42%; MRI 65%. Pathology evaluation of N2/N3 patients indicated LN were replaced with ILC but maintained normal architecture. The average largest pathologic tumor deposit (1.5 ± 0.8 cm) correlated with average largest imaging LN size (1.4 ± 0.6 cm) (p = 0.58). CONCLUSION: A statistically significant difference between clinical and pathologic N-stage exists for ILC patients. MRI was most sensitive for identification of pN2-N3 patients and should be considered part of routine axillary imaging evaluation for ILC patients.

Multidisciplinary Review of Intraductal Papilloma of the Breast can Identify Patients who may Omit Surgical Excision.

BACKGROUND: The purpose of this study was to define contemporary management recommendations regarding who would benefit from surgical excision of intraductal papilloma (IDP). METHODS: A prospective database from a single institution identified patients with IDP on percutaneous biopsy from February 2015 to September 2020. Categorical patient demographic, biopsy, and pathologic variables were analyzed using Fisher's exact test and continuous demographic and imaging variables using the Mann-Whitney U test. RESULTS: IDP was present in 416 biopsies, at a median age of 56 years. The median size was 0.9 cm, and the majority had greater than 50% of the target excised by biopsy. Surgical excision was performed for 124 of 416 biopsies (29.8%). Upgrade to malignancy was identified in 14 (11.3%): 8 to ductal carcinoma in situ (DCIS) and 6 to invasive cancer. Upgrade was significantly associated with concurrent ipsilateral breast cancer (p = 0.027), larger imaging size (p = 0.045), <50% excised with biopsy (p = 0.02), and atypia involving IDP (p = 0.045). Age, clinical presentation, and concurrent contralateral cancer were not significantly associated with upgrade. Lowest upgrade risk (0%) was in pure IDP ≤1 cm with >50% removed by biopsy. Of 401 biopsies that either did not upgrade or undergo excision, 7 (1.7%) developed subsequent breast cancer over a median follow-up of 23.5 months (interquartile range [IQR] 11,41), none at IDP site. CONCLUSIONS: After multidisciplinary review, the management of IDP can be stratified into low- and high-risk for upgrade groups using key criteria. Low-risk group may omit surgical excision, because those patients have 0% risk of upgrade over the limited short-term follow-up.

Does the Addition of Breast MRI Add Value to the Diagnostic Workup of Invasive Lobular Carcinoma?

BACKGROUND: Invasive lobular carcinoma (ILC) has unique histologic growth pattern. Few studies have focused on the value of breast magnetic resonance imaging (MRI) specifically for ILC. We hypothesized that MRI adds value to the diagnostic workup in ILC by better defining the extent of disease and identifying additional foci of malignancy, which can change the surgical plan. MATERIALS AND METHODS: This was a single-institution retrospective review of women diagnosed with ILC from 1/2012 to 7/2019 who underwent preoperative MRI. Patient, tumor characteristics, and initial surgical plan were reviewed. MRI had added value if ILC size correlated best to final pathologic size or if additional malignancy was identified. MRI was considered harmful if additional biopsies were benign or if the size was overestimated. RESULTS: ILC was identified in 166 breasts in 165 women. Original surgical plan was for lumpectomy in 86 (52%), mastectomy in 49 (30%), and undecided in 31 (18%). MRI changed the plan in 25 (19%) with 24 (96%) changing from lumpectomy to mastectomy. Additional biopsy was performed in 28% after MRI, the majority (n = 41, 72%) were benign or high risk and 16 (28%) identified additional malignancy. MRI was not a better size estimate than mammogram/ultrasound. Re-excision rate after lumpectomy was 6.8% (5/73). MRI added value in 48 (28.9%) and was harmful in 48 (28.9%). CONCLUSIONS: Using breast MRI in the diagnostic workup of ILC has both positive and negative implications on surgical treatment planning. A shared decision-making conversation is warranted before proceeding with MRI to maximize value and minimize harms associated with this diagnostic tool.

Secondary angiosarcoma following catheter-based brachytherapy.

Secondary angiosarcoma of the breast following catheter-based brachytherapy after lumpectomy is rare. We describe a case of a patient with breast cancer treated with partial mastectomy and sentinel node biopsy followed by accelerated partial breast irradiation (APBI), who developed skin changes 6 years after completion of therapy. Punch biopsy confirmed the diagnosis of secondary angiosarcoma. This case is even more unique in that the location of the skin changes was remote to the lumpectomy site. There is a critical need to recognize secondary angiosarcoma presentation after APBI and determine the rate of occurrence compared with traditional external beam irradiation.

Ipsilateral and Concurrent Breast Cancer and Atypical Ductal Hyperplasia: Does Atypia Also Need Surgical Excision?

BACKGROUND: Standard-of-care management of atypical ductal hyperplasia (ADH) is surgical excision. Multiple studies have identified features of ADH in patients at low risk for upgrade who may benefit from omission of surgical excision. Patients with an ipsilateral breast cancer have been excluded from studies investigating observation for the management of ADH. METHODS: This was a retrospective review of women with both a breast cancer and an ipsilateral separate site of ADH diagnosed on percutaneous biopsy, who underwent excision of both sites from 2008 to 2018. Radiographic and pathologic features of ADH and cancer were analyzed, including imaging size, biopsy modality, distance between sites, cancer subtype, grade, prognostic markers, ADH foci, and presence of necrosis or micropapillary features. Final pathology at the ADH site was used to determine upgrade. Multivariable logistic regression was performed to identify variables significantly associated with ADH upgrade to malignancy. RESULTS: Among 62 women meeting the inclusion criteria, 11 (17.7%) upgraded to malignancy [9 ductal carcinoma in situ (DCIS), 2 invasive cancer] at the site of ADH. Upgrade was significantly higher with ipsilateral DCIS (p = 0.03), ultrasound biopsy at the ADH site (p = 0.01), and ADH with necrosis (p = 0.04). The group at lowest risk for upgrade had stereotactic biopsy and ADH without necrosis (0% upgrade). CONCLUSION: The presence of breast cancer does not significantly increase the likelihood for upgrade at a separate site of ipsilateral concurrent ADH above contemporary reported upgrade rates of ADH alone (10-30%). When considering breast conservation for breast cancer, omitting excision of the site of ADH can be considered when low-risk features are present.

Primary tumor resection in de novo stage IV breast cancer patients.

Breast and axillary surgery in Stage IV disease is outside current national guidelines but has been a topic of ongoing debate. A single institution retrospective study identified women with de novo stage IV BC from 2011-2016 to evaluate the rate and goals of primary site surgery. Only 10.2% (n = 27/265patients) had primary site surgery. The goal of surgery was most often treatment intent (n = 23, 85.1%) not palliation (n = 4, 14.8%). There was no 30-day mortality and low (n = 1, 3.7%) 30-day morbidity. Multi-disciplinary patient care pathways based on modern evidence may help identify patients potentially suitable for primary site surgery.

Reducing Breast Cancer-Related Lymphedema (BCRL) Through Prospective Surveillance Monitoring Using Bioimpedance Spectroscopy (BIS) and Patient Directed Self-Interventions.

BACKGROUND: Breast cancer-related lymphedema (BCRL) is a chronic progressive disease that results from breast cancer treatment and nodal surgery. NCCN guidelines support baseline measurements with prospective assessment for early diagnosis and treatment. We sought to determine if baseline measurement with bioimpedance spectroscopy (BIS) and serial postoperative evaluations provide early detection amenable to conservative interventions that reduce BCRL. METHODS: Breast cancer patients with unilateral disease high-risk for BCRL from a single institution were evaluated from November 2014 to December 2017. High risk was defined as axillary lymph node dissection with radiation and/or taxane chemotherapy. Patients received preoperative baseline BIS measurements followed by postoperative measurements with at least two follow-ups. Patients with BIS results that were 2 standard deviations above baseline (10 + points) started home conservative interventions for 4-6 weeks. Postintervention measurements were taken to assess improvement. RESULT: A total of 146 patients high-risk for BCRL were included. Forty-nine patients (34%) developed early BCRL and started self-directed treatment. Forty patients (82%) had elevated BIS measurements return to normal baseline range. Nine (6%) patients had persistent BCRL requiring referral for advanced therapy. Patients with persistent BCRL had significant nodal burden on surgical pathology; eight (89%) had N2/N3 disease. Six (76%) with BCRL refractory to conservative measures died of their breast cancer. CONCLUSION: Our results demonstrated that early conservative intervention for breast cancer patients high risk for BCRL who were prospectively monitored by utilizing BIS significantly lowers rates of BCRL. These findings support early prospective screening and intervention for BCRL. Early detection with patient-directed interventions improves patient outcomes and decreases the risk of persistent BCRL.