Atypia Involving Fibroadenomas: Outcomes and Upgrade Rates

OBJECTIVE

Fibroadenomas (FAs) involved by atypia are rare. Consensus guidelines for management of FAs involved by atypia when diagnosed on image-guided biopsy do not exist because of limited data reporting surgical upgrade rates to ductal carcinoma in situ (DCIS) or invasive malignancy. Therefore, these lesions commonly undergo surgical excision.

METHODS

This single-institution retrospective study identified cases of FAs involved by atypical ductal hyperplasia (ADH), atypical lobular hyperplasia (ALH), and/or lobular carcinoma in situ (LCIS) diagnosed on image-guided biopsy between January 2014 and April 2023 to determine upgrade rates. Cases with incidental atypia adjacent to but not involving FAs were excluded.

RESULTS

Among 1736 FAs diagnosed on image-guided biopsy, 32 cases (1.8%) were FAs involved by atypia including 43.8% (14/32) ALH, 28.1% (9/32) ADH, 18.8% (6/32) LCIS, 6.3% (2/32) LCIS + ALH, and 3.1% (1/32) unspecified atypia. The most common imaging finding was a mass. Most cases, 81.3% (26/32), underwent subsequent surgical excisional biopsy. A single case of ADH involving and adjacent to an FA was upgraded to FA involved by low-grade DCIS on excision for an overall surgical upgrade rate of 3.8%. There were no cases upgraded to invasive malignancy. For those omitting surgical excision, there was no subsequent malignancy diagnosis at the FA biopsy site over a mean follow-up of 73 months.

CONCLUSION

Cases of radiologic-pathologic concordant FAs involved by atypia have a low upgrade rate of 3.8% and should undergo multidisciplinary review. Larger multi-institutional analysis is needed to determine whether guidelines for excision of atypia should apply to atypia involving FAs.

Advanced degrees, gender, and professional rank in surgery, disparities in academic medicine

INTRODUCTION

Women comprise nearly half of all residents in training, yet there is a significant disparity of women in academic leadership. Surgical subspecialties are dominated by men in both percentages of physicians and leadership positions. We sought to examine the association of advanced non-medical degrees with academic rank and gender in academic surgery departments.

METHODS

Faculty from 126 ACGME-accredited academic medical centers were analyzed to identify faculty gender as described in online biographical information, advanced non-medical degrees, academic rank, and additional leadership positions held. Descriptive statistics and logistic regression models were used for statistical analyses.

RESULTS

4536 surgeons were identified, 69.3% men, 27.3% female, and 3.3% unlisted. Female surgeons were more likely to hold advanced non-doctoral degrees than men (18.2% vs. 13.8%, p ​< ​0.002). Among those with advanced degrees, PhDs were held by 3.3% of women and 5.7% of men (p ​< ​0.001). Female surgeons were less likely to hold the rank of Professor than male surgeons (15.8% vs 30.3%, p ​< ​0.001), and more likely to hold the rank of Assistant Professor than male surgeons (51.9% vs 36.1%, p ​< ​0.001). This likelihood remained true when analyzing only surgeons with one or more advanced non-medical degrees. Men were more likely to be Chair of Surgery (3.0%), Division Chief (9.6%), and Research Chair (0.5%); compared to women (1.3%; 4.8%; 0.2%; p ​= ​0.001, <0.001, 0.21 respectively).

CONCLUSIONS

There continues to be a significant male predominance in general surgery. Gender discrepancy is also seen in professional rank and academic title despite women holding more advanced degrees. Advanced degrees are currently considered academic qualifications, but this does not reflect surgical academic leadership roles or rank.

Clinical and Biomarker Findings of Neoadjuvant Pembrolizumab and Carboplatin Plus Docetaxel in Triple-Negative Breast Cancer: NeoPACT Phase 2 Clinical Trial

Importance

Addition of pembrolizumab to anthracycline-based chemotherapy improves pathologic complete response (pCR) and event-free survival (EFS) in triple-negative breast cancer (TNBC). The efficacy of anthracycline-free chemoimmunotherapy in TNBC has not been assessed.

Objective

To assess the efficacy of the anthracycline-free neoadjuvant regimen of carboplatin and docetaxel plus pembrolizumab in TNBC.

Design, Setting, and Participants

This was an open-label phase 2 clinical trial including a single group of patients with stage I to III TNBC enrolled at 2 sites who received neoadjuvant carboplatin and docetaxel plus pembrolizumab every 21 days for 6 cycles. Participants were enrolled from 2018 to 2022.

Intervention or Exposure

Carboplatin (with an area under the free carboplatin plasma concentration vs time curve of 6) and docetaxel (75 mg/m2) plus pembrolizumab (200 mg) every 21 days for 6 cycles. Myeloid growth factor support was administered with all cycles.

Main Outcomes and Measures

Primary end point was pathologic complete response (pCR) defined as no evidence of invasive tumor in breast and axilla. The secondary end points were residual cancer burden, EFS, toxicity, and immune biomarkers. RNA isolated from pretreatment tumor tissue was subjected to next-generation sequencing. Specimens were classified as positive or negative for the 44-gene DNA damage immune response (DDIR) signature and for the 27-gene tumor immune microenvironment (TIM; DetermaIO) signature using predefined cutoffs. Stromal tumor-infiltrating lymphocytes (sTILs) were evaluated using standard criteria. Programmed cell death-ligand 1 (PD-L1) testing was performed using a standard immunohistochemical assay.

Results

Among the eligible study population of 115 female patients (median [range] age, 50 [27-70] years) who enrolled from September 2018 to January 2022, 39% had node-positive disease. pCR and residual cancer burden 0 + 1 rates were 58% (95% CI, 48%-67%) and 69% (95% CI, 60%-78%), respectively. Grade 3 or higher immune-mediated adverse events were observed in 3.5% of patients. sTILs, PD-L1, DDIR, and TIM were each predictive of pCR in multivariable analyses. The areas under curve for pCR were 0.719, 0.740, 0.699, and 0.715 for sTILs, PD-L1, DDIR, and TIM, respectively. Estimated 3-year EFS was 86% in all patients; 98% in pCR group and 68% in no-pCR group.

Conclusions and Relevance

The findings of the phase 2 clinical trial indicate that neoadjuvant carboplatin and docetaxel plus pembrolizumab shows encouraging pCR and 3-year EFS. The regimen was well tolerated, and immune enrichment as identified by various biomarkers was independently predictive of pCR. These results provide data on an alternative anthracycline-free chemoimmunotherapy regimen for patients who are not eligible for anthracycline-based regimens and support further evaluation of this regimen as a chemotherapy de-escalation strategy in randomized studies for TNBC.

Trial Registration

ClinicalTrials.gov Identifier: NCT03639948.

Oncoplastic Breast Reconstruction for Large Pediatric Breast Tumors: A Case Series

ABSTRACT

Large breast fibroadenomas in pediatric females may cause discomfort, asymmetry, and psychological stress, and patients may elect for surgical excision. There are no criteria for reconstruction after the excision of these masses, and the research is limited in describing oncoplastic techniques in pediatric fibroadenoma excision. Nononcoplastic techniques, such as mastectomy with implant or flap reconstruction, have been used for pediatric fibroadenoma excision reconstruction. Oncoplastic techniques using Wise pattern or circumareolar incisions have shown to have efficacious outcomes. In addition, pediatric females undergoing breast surgery risk long-term complications such as continued breast asymmetry due to further breast growth, nipple and breast hypoesthesia, and future breastfeeding difficulty. This case series describes the oncoplastic techniques used for large benign mass excision and reconstruction of 3 pediatric females. A Wise pattern technique was used for all 3 patients, and 2 underwent a free-nipple graft. Oncoplastic techniques for pediatric breast mass excision provide satisfactory aesthetic outcomes with minimal surgical morbidity. Further research assessing the long-term effects of pediatric breast mass excision and reconstruction would be beneficial.

Use of Ultrasound and Ki-67 Proliferation Index to Predict Breast Cancer Tumor Response to Neoadjuvant Endocrine Therapy

BACKGROUND

Prediction of tumor shrinkage and pattern of treatment response following neoadjuvant endocrine therapy (NET) for estrogen receptor positive (ER+), Her2 negative (Her2-) breast cancers have had limited assessment. We examined if ultrasound (US) and Ki-67 could predict the pathologic response to treatment with NET and how the pattern of response may impact surgical planning.

METHODS

A total of 103 postmenopausal women with ER+, HER2- breast cancer enrolled on the FELINE trial had Ki-67 obtained at baseline, day 14, and surgical pathology. A total of 70 patients had an US at baseline and at the end of treatment (EOT). A total of 48 patients had residual tumor bed cellularity (RTBC) assessed. The US response was defined as complete response (CR), partial response (PR), stable disease (SD), and progressive disease (PD). CR or PR on imaging and ≤70% residual tumor bed cellularity (RTBC) defined a contracted response pattern.

RESULTS

A decrease in Ki-67 at day 14 was not predictive of EOT US response or RTBC. A contracted response pattern was identified in one patient with CR and in sixteen patients (33%) with PR on US. Although 26 patients (54%) had SD on imaging, 22 (85%) had RTBC ≤70%, suggesting a non-contracted response pattern of the tumor bed. The remaining four (15%) with SD and five with PD had no response.

CONCLUSION

Ki-67 does not predict a change in tumor size or RTBC. NET does not uniformly result in a contracted response pattern of the tumor bed. Caution should be taken when using NET for the purpose of downstaging tumor size or converting borderline mastectomy/lumpectomy patients.

Relationship Between Gender, Training Level and Goal Orientation Achievement Motivation: Implications for Learners and Faculty

PURPOSE

Achievement goal orientation (GO) theory describes Mastery (M), one's intrinsic drive for competency for the sake of competency, and performance approach (PAP), a drive for competency by displaying competency, which are both adaptive. In learners motivated by performance avoid (PAV), showing competency by avoiding appearing incompetent dominates (maladaptive). The aim of this study was to determine differences in GO by gender and training (PGY) level.

METHODS

A prospective, multi-institutional cohort of general surgery trainees participated in a cross-sectional study (2020-2021). Participants completed a 10-item instrument (the Goal Orientation in Surgical Trainees, GO-ST) measured on a 5-pointLikert scale (1 = never,3 = weekly,5 = daily). Student's t-tests and ANOVA F-test were used as appropriate.

RESULTS

A total of 144/164 trainees participated (87.8%). The sample was 40.0%(n = 56) female and 57.9%(n = 81) male; 21.3%(n = 30) were PGY1, 22.0%(n = 31) PGY2, 24.8%(n = 35) PGY3, 18.4%(n = 26) PGY4, 13.5%(n = 19) PGY5. There were no significant differences in mean scale scores by gender for Mastery (3.3 vs 3.5; p = 0.17), or PAP (3.7 vs 3.5; p = 0.10), but mean PAV scores were significantly higher for females (3.6 vs 3.3; p = 0.04). While there were no significant differences in mean Mastery and PAP scale scores by training level (p = 0.44; p = 0.31), there was a significant difference in PAV scores (p < 0.01). The frequency of PAV feelings decreased over 5 years.

CONCLUSIONS

Only PAV motivation differed by gender and training level. Understanding the psychology of motivation with this framework can aid both residents and programs in re-focusing on more adaptive learning strategies and supporting trainees in their transition to master surgeons.

Clinical and biomarker results of neoadjuvant phase II study of pembrolizumab and carboplatin plus docetaxel in triple-negative breast cancer (TNBC) (NeoPACT)

513

Background: Addition of pembrolizumab to anthracycline-taxane-platinum chemotherapy improves pathologic complete response (pCR) and event free survival (EFS) in TNBC. Aim of this study was to assess the efficacy of the anthracycline free neoadjuvant regimen of pembrolizumab plus carboplatin plus docetaxel (Cb+D) in TNBC. Methods: In this multicenter study, eligible patients with stage I-III TNBC received carboplatin (AUC 6) + docetaxel (75 mg/m2) + pembrolizumab (200 mg) every 21 days x 6 cycles. The primary endpoint was pCR (no evidence of invasive tumor in breast and axilla). Secondary endpoints were residual cancer burden (RCB), EFS, toxicity, and immune response biomarkers. RNA isolated from pretreatment tumor tissue was subjected to next generation sequencing. Samples were classified as DNA Damage Immune Response (DDIR) signature and DetermaIO signature positive/negative using predefined cutoffs. Evaluation of stromal tumor infiltrating lymphocytes (sTILs) was performed using standard criteria. Results: 117 patients were enrolled from September 2018 to January 2022. 18% were African American, 39% had node positive disease, 88% had stage II/III disease and 15% had ER/PR 1-10%. Pathologic response information is available for 105 patients. pCR and RCB 0+1 rates were 60% (95% CI 51%-70%) and 71% (95% CI 62%-80%), respectively. Treatment related adverse events led to discontinuation of any trial drug in 12% of patients. Immune adverse events were observed in 28% of patients (Grade ≥3=6%). 47% of patients had sTILs ≥30%, 48% were DetermaIO positive, and 61% DDIR positive. The table describes the impact of these biomarkers on pCR and RCB. The areas under the prediction curve (AUC) for pCR were 0.660, 0.709, and 0.719 for DDIR, sTILs, and DetermaIO respectively. At a median follow up of 21 months, 2-year EFS is 88% in all patients; 98% in pCR group and 82% in no pCR group. Conclusions: Neoadjuvant pembrolizumab plus Cb+D regimen yields pCR of 60% and 2-year EFS of 88% in the absence of adjuvant pembrolizumab. The regimen was well tolerated, and no new toxicity signals were noted. Immune enrichment identified by sTILs or DetermaIO signature was associated with high pCR rates approaching or exceeding 80%. PD-L1 and additional biomarker analyses are ongoing. Clinical trial information: NCT03639948. [Table: see text]

Abstract P5-01-03: Mouse-intraductal (MIND): An in vivo model for studying the underlying mechanisms of DCIS malignancy

Background: 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. Methods: To address this gap, we developed an in vivo model, Mouse-INtraDuctal (MIND), by which patient-derived DCIS epithelial cells are injected intraductally and allowed to progress naturally in mice. The source of DCIS samples reflected clinical practice as predominantly high grade (70%), but also included intermediate grade (27%) and low grade (3%). Thirty-seven patient samples were injected into 202 mouse mammary glands and evaluated for invasive progression at a median duration of 9 months. The expression of clinically relevant biomarkers (ER, PR, Ki-67, HER2 and p53) on patient DCIS FFPE sections and xenografts’ extent of in vivo growth were evaluated for their utility in predicting DCIS invasive progression in the xenografts. Targeted DNA sequencing using Tempus XT oncology assay was used on patient DCIS in order to find a unique pattern of cancer related gene mutations that predicted DCIS invasiveness in the xenografts. Results: 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 noninvasive. Among the 20 samples that showed invasive progression in the MIND model, 9 patient samples injected into 54 xenografts exhibited a mixed pattern in which some xenografts showed invasive progression while others remained noninvasive. The mean duration of follow-up was not significantly different among the progressed, non-progressed or mixed groups (ANOVA; p-value=0.44). Among the clinically relevant biomarkers, only elevated progesterone receptor expression in patient DCIS and extent of in vivo growth in xenografts predicted an invasive outcome in the xenografts. Tempus XT oncology assay was used on 16 patient DCIS FFPE sections including eight patient DCIS that showed invasive progression (P), five patient DCIS that remained non-invasive (NP) and three patient DCIS that showed a mixed pattern (M) in the xenografts. Variant severity was called using SnpSift which is a program for identifying phenotype-relevant variants and predicts the severity of SNPs based on their effect on gene expression and function. COSMIC database was also used to identify mutations with pathogenic scores &gt;0.5. Analysis of the frequency of cancer related pathogenic mutations showed no significant differences (P=27, NP=79, M=43, Kruskal-Wallis: P value=&gt;0.05). There were also no differences in the frequency of low, moderate or high severity mutations (P= 25 highly severe, 120 moderately severe and 50 low-severity; NP=9 highly severe, 58 moderately severe and 28 low severity; M=3 highly severe, 33 moderately severe and 14 low severity; Kruskal-Wallis; P value &gt;0.05). Conclusions: Highly severe and pathogenic variants in the patient’s DCIS were not associated with whether the DCIS developed into invasive lesions or remained non-invasive in the MIND models. These results are in agreement with previous studies that showed no significant differences in frequency of non-synonymous mutations and CNAs when comparing pure DCIS with synchronous IDC-DCIS. The MIND models are in immunocompromised mice, so the contribution of the immune system to DCIS progression may not recapitulate cancer progression in an immunocompetent state. However, the MIND model suggests that genetic changes in the DCIS are not the primary driver for the development of invasive disease.

Citation Format: Aditi Rastogi, Jerome Lin, Yan Hong, Darlene Limback, Hanan S. Elsarraj, Haleigh Harper, Haley Haines, Hayley Hansford, Michael Ricci, Carolyn Kaufman, Emily Wedlock, Mingchu Xu, Jianhua Zhang, Lisa May, Terri Cusick, Marc Inciardi, Mark Redick, Jason Gatewood, Onalisa Winblad, Allison Aripoli, Ashley Huppe, Christa Balanoff, Jamie Wagner, Amanda Amin, Kelsey E. Larson, Lawrence Ricci, Ossama Tawfik, Hana Razek, Ruby O Meierotto, Rashna Madan, Andrew K. Godwin, Jeffrey Thompson, Susan G. Hilsenbeck, Andy Futreal, Alastair Thompson, E. Shelley Hwang, Fang Fan, Nicholas Navin, Fariba Behbod, Grand Challenge PRECISION Consortium. Mouse-intraductal (MIND): An in vivo model for studying the underlying mechanisms of DCIS malignancy [abstract]. In: Proceedings of the 2021 San Antonio Breast Cancer Symposium; 2021 Dec 7-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2022;82(4 Suppl):Abstract nr P5-01-03.

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.

Abstract PD5-09: Mouse-intraductal (MIND): The first in vivo model to recapitulate the full spectrum of human DCIS pathology

Introduction. Due to advances in imaging technology and an increase in mammographic screening, there has been a significant increase in the diagnosis rate of ductal carcinoma in situ (DCIS). At the present time, nearly all women undergo surgical removal of DCIS, often followed by adjuvant radiation and in some cases anti-hormonal therapy. Currently, there are no means by which to diagnose DCIS accurately, or to predict which patients benefit from aggressive therapy. Thus, the recommendation for surgery persists, despite studies which support that not all DCIS will subsequently progress to invasive disease. In this context, animal models can be particularly useful in studying DCIS progression. Here, we present the first in vivo model of DCIS, referred to as Mouse-INtraDuctal (MIND), in which patient-derived DCIS epithelial cells are injected intraductally and allowed to progress naturally in mice. Methods. We performed intraductal injection of DCIS epithelial cells derived from 30 patient samples into 194 total glands. Of the 194, 146 xenografts showed in vivo growth, for a 75% take rate). Among the DCIS samples injected into mice, 18 (103 mouse mammary glands) were followed for a median of 9 months . Among those, 50% (9) showed invasive progression while 50% (9) remained non-invasive. DCIS invasive progression was evaluated by performing immunofluorescene staining using anti-smooth muscle actin (SMA) antibody and confirmed by the loss of SMA around the xenografted DCIS like lesions on 3 consequetive sections of FFPE tissues. Results. Progressed xenografts exhibited invasive progression, evident by the loss of SMA, as early as 6 months following transplantation. Similar to human DCIS, the cancer cells initially formed in situ lesions inside the mouse mammary ducts and mimicked all histologic subtypes including micropapillary, papillary, cribriform, solid and comedo. Among the biomarkers tested, including ER, PR, Ki67, HER2, p53, histology, nuclear and tumor grade, only low ER & PR expression and extent of DCIS growth in xenografts significantly correlated with invasive progression. A high depth targeted sequencing platform (T200) on DNA isolated from LCM captured DCIS of patient and xenograft pairs identified shared (i.e., EGFR) as well as unique (STK11, RUNX1, PIK3CA) mutations in patient/xenograft pairs. Notably, we also observed private mutations that were not shared within the same patient/xenograft pairs. These results indicate the presence of DCIS clonal heterogeneity and that DCIS xenografts may represent one or more clonal subpopulations of patient DCIS. Conclusion. The MIND model represents the first realistic in vivo model that recapitulates human DCIS progression in a manner that represents the inter- and intra-tumoral heterogeneity of human disease. These innovative mouse models will be invaluable for the discovery of molecular signatures of invasive DCIS by allowing comparison of xenografts with variable propensity for invasive progression. These models will enable the discovery of extrinsic factors that regulate DCIS malignancy as well as testing of pharmaceutical and natural compounds for prevention of DCIS progression to invasive disease.

Citation Format: Fariba Behbod, Yan Hong, Darlene Limback, Hannan S Elsarraj, Haleigh Harper, Haley Haines, Hayley Hansford, Michael Ricci, Carolyn Kaufman, Mingchu Xu, Jianhua Zhang, Lisa May, Therese Cusick, Marc inciardi, Mark Redick, Jason Gatewood, Alison Aripoli, Ashley Huppe, Onalisa Winblad, Christa Balanoff, Jamie Wagner, Amanda L Amin, Kelsey E. Larson, Lawrence Ricci, Ossama Tawfik, Hana Razek, Ruby O Meierotto, Rashna Madan, Andrew K Godwin, Jeffrey Thompson, Andy Futreal, Alastair Thompson, Shelley Hwang, Fang Fan, On behalf of the Grand Challenge PRECISION consortium. Mouse-intraductal (MIND): The first in vivo model to recapitulate the full spectrum of human DCIS pathology [abstract]. In: Proceedings of the 2020 San Antonio Breast Cancer Virtual Symposium; 2020 Dec 8-11; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2021;81(4 Suppl):Abstract nr PD5-09.

Randomized Phase II Trial of Anthracycline-free and Anthracycline-containing Neoadjuvant Carboplatin Chemotherapy Regimens in Stage I-III Triple-negative Breast Cancer (NeoSTOP)

PURPOSE

Addition of carboplatin (Cb) to anthracycline chemotherapy improves pathologic complete response (pCR), and carboplatin plus taxane regimens also yield encouraging pCR rates in triple-negative breast cancer (TNBC). Aim of the NeoSTOP multisite randomized phase II trial was to assess efficacy of anthracycline-free and anthracycline-containing neoadjuvant carboplatin regimens.

PATIENTS AND METHODS

Patients aged ≥18 years with stage I-III TNBC were randomized (1:1) to receive either paclitaxel (P) weekly × 12 plus carboplatin AUC6 every 21 days × 4 followed by doxorubicin/cyclophosphamide (AC) every 14 days × 4 (CbP → AC, arm A), or carboplatin AUC6 + docetaxel (D) every 21 days × 6 (CbD, arm B). Stromal tumor-infiltrating lymphocytes (sTIL) were assessed. Primary endpoint was pCR in breast and axilla. Other endpoints included residual cancer burden (RCB), toxicity, cost, and event-free (EFS) and overall survival (OS).

RESULTS

One hundred patients were randomized; arm A (n = 48) or arm B (n = 52). pCR was 54% [95% confidence interval (CI), 40%-69%] in arm A and 54% (95% CI, 40%-68%) in arm B. RCB 0+I rate was 67% in both arms. Median sTIL density was numerically higher in those with pCR compared with those with residual disease (20% vs. 5%; P = 0.25). At median follow-up of 38 months, EFS and OS were similar in the two arms. Grade 3/4 adverse events were more common in arm A compared with arm B, with the most notable differences in neutropenia (60% vs. 8%; P < 0.001) and febrile neutropenia (19% vs. 0%; P < 0.001). There was one treatment-related death (arm A) due to acute leukemia. Mean treatment cost was lower for arm B compared with arm A (P = 0.02).

CONCLUSIONS

The two-drug CbD regimen yielded pCR, RCB 0+I, and survival rates similar to the four-drug regimen of CbP → AC, but with a more favorable toxicity profile and lower treatment-associated cost.

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.

Results of randomized phase II trial of neoadjuvant carboplatin plus docetaxel or carboplatin plus paclitaxel followed by AC in stage I-III triple-negative breast cancer (NCT02413320)

516

Background: Addition of neoadjuvant carboplatin (Cb) to paclitaxel (T) followed by doxorubicin + cyclophosphamide (AC) improves pathologic complete response (pCR) rate compared to T/AC in TNBC. An anthracycline-free regimen of Cb plus docetaxel (D) also yields high pCR rates in TNBC, and patients achieving pCR with this regimen demonstrate excellent 3-year outcomes without adjuvant anthracycline. This study was designed to compare the efficacy of neoadjuvant regimens CbT→AC and CbD in TNBC. Methods: In this multicenter study, eligible patients with stage I–III TNBC were randomized (1:1) to either paclitaxel 80 mg/m2 every week X 12 + carboplatin (AUC 6) every 3 weeks X 4, followed by doxorubicin 60 mg/m2 + cyclophosphamide 600 mg/m2 every 2 weeks X 4 (CbT→AC, Arm A), or to carboplatin (AUC 6) + docetaxel (75 mg/m2) every 21 days X 6 cycles (CbD, Arm B). The primary endpoint was pCR (no evidence of invasive tumor in the breast and axilla). The two regimens were compared for differences in pCR, residual cancer burden (RCB), treatment delivery, and toxicity. Results: Between 2015 and 2018, 100 patients were randomized; 48 to Arm A and 52 to Arm B. Median age was 52 years, median tumor size was 2.7 cm, 30% were lymph node-positive and 17% carried a BRCA1/2 mutation. Baseline demographic and tumor characteristics were balanced between two arms. pCR was 55% (95%CI: 41%-59%) in Arm A and 52% (95%CI: 39%-65%) in Arm B, p =0.84. RCB 0+1 rate was 67% in both arms. Grade 3/4 adverse events were more common in Arm A compared to Arm B (73% vs 21%, p < 0.0001), with most notable differences in rates of G3/4 neutropenia (Arm A = 60%, Arm B = 8%, p = 0.0001), febrile neutropenia (Arm A = 18%, Arm B = 0%, p = 0.0001), and G3/4 anemia (Arm A = 46%, Arm B = 4%, p = 0.0001). 81% of Arm A patients completed all 4 doses of AC and 4 doses of Cb, and 71% completed > 9 doses of T. 90% of Arm B patients completed all 6 doses of CbD (p = 0.034). Conclusions: The non-anthracycline platinum regimen of CbD yields pCR and RCB 0+1 rates similar to 4-drug regimen of CbTàAC, but with a more favorable toxicity profile and higher treatment completion rate. The CbD regimen should be further explored as a way to de-escalate therapy in TNBC. Clinical trial information: NCT02413320.

Comparison of terminal duct lobular units in the nipple areolar complex by tumor subtypes-the implication for nipple sparing mastectomy

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Background: Nipple-sparing mastectomy (NSM) has gained popularity for surgical treatment of breast cancer. Terminal duct lobular units (TDLU) have been shown to be present in 25% of nipple areolar complex (NAC). Pathologic tumor subtype influence on presence of TDLU in the NAC has not been assessed. In addition, criteria for technically performing the dissection below the NAC have not been established. We sought to evaluate TDLU characteristics by tumor subtype and determine NSM dissection criteria below the NAC. Methods: A retrospective review was performed of 120 total and skin sparing mastectomies, 30 of each breast cancer subtype, from 1/2013 to 1/2015. The NAC of each mastectomy was assessed for number of TDLU and distance from TDLU to the skin. Results: Thirty of the 120 mastectomies (25%) had TDLU present below the NAC. Of the 30 with TDLU, there was no statistically significant difference in number of TDLU present based on tumor grade (gd) (gd 1 vs 2, p = .67; gd 1 vs 3, p = .24). Compared to luminal A, luminal B showed statistical significance (p < .05) for number of TDLU at the NAC whereas Her 2 and triple negative breast cancer (TNBC) were not statistically significant (p = .09 and .10). In mastectomies with TDLU present, gd 2 (p < .05) and gd 3 (p = .05) had a closer skin distance than gd 1. When compared by tumor subtype, there was no difference in TDLU to skin distance (table). Conclusions: NSM has been adopted as a safe oncologic approach to breast cancer treatment. Although presence of TDLU in luminal B subtype was statistically significant, this may not be clinically significant, as there were only 2 of 30 cases with TDLU. Our study indicates that a careful dissection at the level of the dermis below the NAC is necessary, as 25% of women will have TDLU present. This will provide an appropriate oncologic outcome similar to total and skin sparing mastectomy. Tumor subtype does not appear to be exclusion criteria for NSM. However, more aggressive dissection may be necessary to clear all TDLU from below the NAC in higher gd cancers. [Table: see text]

Gastric tonometry and direct intraabdominal pressure monitoring in abdominal compartment syndrome

BACKGROUND/PURPOSE

Abdominal compartment syndrome (ACS) may complicate abdominal closure in patients with abdominal wall defects, abdominal trauma, intraperitoneal bleeding, and infection. Increased intraabdominal pressure (IAP) leads to respiratory compromise, organ hypoperfusion, and a high mortality rate. This study evaluates the efficacy of continuous direct monitoring of IAP and gastric tissue pH in detecting impending ACS.

METHODS

Ten mongrel puppies weighing 2.8 to 6.4 kg underwent general endotracheal anesthesia, placement of an intraabdominal inflatable balloon to simulate ACS and a Swan-Ganz catheter to measure direct IAP. A gastric tonometer, nasogastric tube, foley catheter, and arterial catheter also were inserted. Half-hourly inflation's of the intraabdominal balloon were used to simulate the development of ACS. Direct intraabdominal (IAP), gastric (GP), bladder (BP), and peak airway pressures (PAP) were measured. Gastric tonometry fluid and arterial blood gas levels were obtained during inflation, and the gastric tissue pH level was calculated. Data were statistically analyzed using Pearson's correlation coefficients.

RESULTS

Baseline pressures were 2 to 5 cm H(2)O in the stomach and bladder catheters, 1 to 3 mm Hg in the intraabdominal catheter, and correlated with a gastric tissue pH level of 7.4. Significantly high correlation coefficients (cc) were observed between IAP versus BP (cc, 0.77; P <.002). IAP versus GP (cc, 0.79; P <.002) and IAP versus PAP (c, 0.83; P <.0004). A high negative correlation coefficient was noted between gastric pH and IAP (cc, 0.61; P <.026). The pH level dropped to 7.0 with BP and GP of 20 cm H(2)O and IAP of 10 mm Hg, to 6.8 at 30 cm H(2)O and 20 mm Hg, and 6.5 at 40 cm H(2)O and 30 mm Hg, respectively. However, correlation coefficients between gastric tissue pH and BP, GP, or PAP were not significant.

CONCLUSIONS

These data suggest that continuous direct intraabdominal pressure monitoring is a simple and effective method that correlates well with indirect bladder or gastric pressure measurement. Changes in gastric tissue pH in association with increased intraabdominal pressure may be an early indicator of impending abdominal compartment syndrome. These observations indicate that these techniques may be more sensitive than current methods of indirect measurement, which may be associated with delayed recognition of ACS.