The Prevalence of Sentinel Lymph Node Positivity and Implications for the Utility of Frozen Section Diagnosis Following Neoadjuvant Systemic Therapy in Patients with Clinically Node-Negative HER2-Positive or Triple-Negative Breast Cancer.

BACKGROUND: Axillary dissection is the standard of care for patients with positive sentinel lymph nodes (SLNs) following neoadjuvant systemic therapy. Frozen section can provide intraoperative information regarding the need for axillary dissection during the index operation. However, there are limited data on the utility of frozen section in patients with clinically node-negative (cN0) HER2-positive or triple-negative breast cancer. METHODS: We conducted a single-institution observational cohort study including patients with non-inflammatory, cN0, HER2-positive or triple-negative breast cancer treated with neoadjuvant systemic therapy between 2015 and 2019. We estimated the prevalence of SLN positivity and the diagnostic test characteristics of SLN frozen section. RESULTS: Overall, 662 patients were eligible for inclusion, and 44 patients had one or more positive SLNs (prevalence: 6.6%, 95% confidence interval [CI] 4.9-8.8). There were 490 (74.0%) patients who had intraoperative frozen section, and 19 (3.9%) tested positive among 33 (6.7%) with positive final pathology. Frozen section sensitivity was 57.6% (95% CI 39.2-74.5), specificity was 100% (95% CI 99.2-100), positive predictive value was 100% (95% CI 82.4-100), and negative predictive value was 97.0% (95% CI 95.1-98.4). The sensitivity of frozen section for detection of micrometastases or isolated tumor cells was 35.3% (95% CI 14.2-61.7). CONCLUSION: In patients with cN0 HER2-positive or triple-negative breast cancer who have been treated with neoadjuvant therapy, positive SLNs are uncommon and frozen section sensitivity is modest. Decisions to defer SLN evaluation to final pathology, which may be reasonable in many settings, can be informed, in part, by these findings.

Self-Reported Management of Inflammatory Breast Cancer Among the American Society of Breast Surgeons Membership: Consensus and Opportunities.

BACKGROUND: Inflammatory breast cancer (IBC) is rare and biologically aggressive. We sought to assess diagnostic and management strategies among the American Society of Breast Surgeons (ASBrS) membership. PATIENTS AND METHODS: An anonymous survey was distributed to ASBrS members from March to May 2023. The survey included questions about respondents' demographics and information related to stage III and IV IBC management. Agreement was defined as a shared response by >80% of respondents. In areas of disagreement, responses were stratified by years in practice, fellowship training, and annual IBC patient volume. RESULTS: The survey was administered to 2337 members with 399 (17.1%) completing all questions and defining the study cohort. Distribution of years in practice was 26.0% 0-10 years, 26.6% 11-20 years and 47.4% > 20 years. Overall, 51.2% reported surgical oncology or breast fellowship training, 69.2% maintain a breast-only practice, and 73.5% treat < 5 IBC cases/year. Agreement was identified in diagnostic imaging, trimodal therapy, and mastectomy with wide skin excision for stage III IBC. Lack of agreement was identified in surgical management of the axilla; respondents with < 10 years in practice or fellowship training were more likely to perform axillary dissection for cN0-N2 stage III IBC. Locoregional management of stage IV IBC was variable. CONCLUSIONS: Among ASBrS members, there is consensus in diagnostic evaluation, treatment sequencing and surgical approach to the breast in stage III IBC. Differences exist in surgical management of the cN0-2 axilla with uptake of de-escalation strategies. Clinical trials are needed to evaluate oncologic safety of de-escalation in this high-risk population.

Neoadjuvant Therapy Versus Upfront Resection for Nonpancreatic Periampullary Adenocarcinoma.

BACKGROUND: In contrast to pancreatic ductal adenocarcinoma (PDAC), neoadjuvant therapy (NAT) for periampullary adenocarcinomas is not well studied, with data limited to single-institution retrospective reviews with small cohorts. We sought to compare outcomes of NAT versus upfront resection (UR) for non-PDAC periampullary adenocarcinomas. PATIENTS AND METHODS: Using the National Cancer Database (NCDB), we identified patients who underwent surgery for extrahepatic cholangiocarcinoma, ampullary adenocarcinoma, or duodenal adenocarcinoma from 2006 to 2016. We compared outcomes between NAT versus UR groups for each tumor subtype with 1:3 propensity score matching. Cox regression was used to identify predictors of survival. RESULTS: Among 7656 patients who underwent resection for non-PDAC periampullary adenocarcinoma, the proportion of patients who received NAT increased from 6 to 11% for cholangiocarcinoma (p < 0.01), 1 to 4% for ampullary adenocarcinoma (p = 0.01), and 5 to 8% for duodenal adenocarcinoma (p = 0.08). Length of stay, readmission, and 30-day mortality were comparable between NAT and UR. All tumor subtypes were downstaged following NAT (p < 0.01). The R0 resection rate was significantly higher in patients with extrahepatic cholangiocarcinoma who received NAT, and these patients had improved median overall survival (38 vs 26 months, p < 0.001). After adjustment for clinicopathologic factors and adjuvant chemotherapy, use of NAT was associated with improved survival in patients with cholangiocarcinoma [hazard ratio (HR) 0.69, 95% confidence interval (CI) 0.54-0.89, p = 0.004] but not duodenal or ampullary adenocarcinoma. The survival advantage for cholangiocarcinoma persisted after propensity matching. CONCLUSION: This national cohort analysis suggests, for the first time, that neoadjuvant therapy is associated with improved survival in patients with extrahepatic cholangiocarcinoma.

Clinical Outcomes for BRCA Pathogenic Variant Carriers With Breast Cancer Undergoing Breast Conservation.

Importance: Although most women with BRCA-associated breast cancer choose bilateral mastectomy, current guidelines support breast-conserving therapy as an option. As the indications for genetic testing expand and targeted therapies emerge, understanding the outcomes of breast-conserving therapy in the population of patients choosing breast conservation is important. Objective: To describe the clinical outcomes of women with BRCA-associated breast cancer who were treated with breast-conserving therapy, including the risks of ipsilateral and contralateral cancer events and bilateral mastectomy-free survival. Design, Setting, and Participants: This cohort study conducted at a single-institution academic national comprehensive cancer center included 172 women identified from a prospectively maintained database who had pathogenic BRCA1/2 variants and were treated with breast-conserving therapy from January 1, 1977, to December 31, 2021. Main Outcomes and Measures: Clinical and pathologic characteristics for patients with BRCA1 and BRCA2 were compared, and estimates of overall survival, bilateral mastectomy-free survival, distant disease-free survival, risk of ipsilateral breast cancer, and risk of contralateral cancer were computed. Results: The cohort included 172 women (mean [SD] age, 47.1 [11.7] years), with 42 (24.4%) receiving a diagnosis of breast cancer prior to 40 years of age. Compared with BRCA2 variant carriers (80 [46.5%]), women with BRCA1 variants (92 [53.5%]) were younger at breast cancer diagnosis and tended to have more advanced tumors, which were more likely to be hormone receptor negative and higher grade. At a median follow-up of 11.8 years (IQR, 5.7-18.2 years), estimates of 10-year survival and risk were: overall survival, 88.5% (95% CI, 83.1%-94.2%); bilateral mastectomy-free survival, 70.7% (95% CI, 63.3%-78.9%); risk of an ipsilateral breast cancer event, 12.2% (95% CI, 5.8%-18.2%); and risk of contralateral cancer, 21.3% (95% CI, 13.3%-28.6%). Risks continued to increase after 10 years of follow-up. Conclusions and Relevance: In this cohort study, although women with breast cancer and pathogenic BRCA1/2 variants treated with breast-conserving therapy had above-average risks of ipsilateral and contralateral breast cancer events, most did not have another cancer event and remained bilateral mastectomy free. These findings may be useful for informing patients with BRCA variants choosing breast conservation.

Tumor microenvironmental determinants of high-risk DCIS progression.

Ductal carcinoma in situ (DCIS) constitutes an array of morphologically recognized intraductal neoplasms in the mammary ductal tree defined by an increased risk for subsequent invasive carcinomas at or near the site of biopsy detection. However, only 15-45% of untreated DCIS cases progress to invasive cancer, so understanding mechanisms that prevent progression is key to avoid overtreatment and provides a basis for alternative therapies and prevention. This study was designed to characterize the tumor microenvironment and molecular profile of high-risk DCIS that grew to a large size but remained as DCIS. All patients had DCIS lesions >5cm in size with at least one additional high-risk feature: young age (<45 years), high nuclear grade, hormone receptor negativity, HER2 positivity, the presence of comedonecrosis, or a palpable mass. The tumor immune microenvironment was characterized using multiplex immunofluorescence to identify immune cells and their spatial relationships within the ducts and stroma. Gene copy number analysis and whole exome DNA sequencing identified the mutational burden and driver mutations, and quantitative whole-transcriptome/gene expression analyses were performed. There was no association between the percent of the DCIS genome characterized by copy number variants (CNAs) and recurrence events (DCIS or invasive). Mutations, especially missense mutations, in the breast cancer driver genes PIK3CA and TP53 were common in this high-risk DCIS cohort (47% of evaluated lesions). Tumor infiltrating lymphocyte (TIL) density was higher in DCIS lesions with TP53 mutations (p=0.0079) compared to wildtype lesions, but not in lesions with PIK3CA mutations (p=0.44). Immune infiltrates were negatively associated with hormone receptor status and positively associated with HER2 expression. High levels of CD3+CD8- T cells were associated with good outcomes with respect to any subsequent recurrence (DCIS or invasive cancer), whereas high levels of CD3+Foxp3+ Treg cells were associated with poor outcomes. Spatial proximity analyses of immune cells and tumor cells demonstrated that close proximity of T cells with tumor cells was associated with good outcomes with respect to any recurrence as well as invasive recurrences. Interestingly, we found that myoepithelial continuity (distance between myoepithelial cells surrounding the involved ducts) was significantly lower in DCIS lesions compared to normal tissue (p=0.0002) or to atypical ductal hyperplasia (p=0.011). Gene set enrichment analysis identified several immune pathways associated with low myoepithelial continuity and a low myoepithelial continuity score was associated with better outcomes, suggesting that gaps in the myoepithelial layer may allow access/interactions between immune infiltrates and tumor cells. Our study demonstrates the immune microenvironment of DCIS, in particular the spatial proximity of tumor cells and T cells, and myoepithelial continuity are important determinants for progression of disease.

Graft choice in pancreatectomy with vascular resection: equivalent safety in selected patients.

BACKGROUND: Pancreatic cancer is the third leading cause of cancer-related death in the United States, with surgical resection being the only option for long-term survival. The ability to manage vascular involvement has expanded the pool of patients who are able to undergo resection with curative intent. However, not all vascular involvements can be detected preoperatively. This study aimed to investigate the patterns of vascular resection and methods of repair or reconstruction METHODS: This was a single-center retrospective review of adult patients undergoing pancreatectomy with vascular involvement at a tertiary care referral hospital between 2010 and 2022. The primary endpoint was graft thrombosis within 90 days. RESULTS: A total of 147 patients were included in the study. Of note, 21.8% of patients were not suspected of having vascular involvement preoperatively. Moreover, 68.0% of patients required vascular reconstruction, whereas the remaining 32.0% of patients underwent repair (either primary repair or patch angioplasty). Most patients who underwent reconstruction underwent primary end-to-end anastomosis (63.0%), with 19 patients requiring autologous interposition grafts and 16 patients requiring CryoVein interposition grafts. Univariate analysis found no clinical or technical predictors of early or 90-day thrombosis, including graft choice. In addition, 30- and 90-day mortalities occurred in 1 and 7 patients, respectively. CONCLUSION: Pancreatectomy with vascular resection can be performed with low mortality in carefully selected patients. Unsuspected vascular involvement is relatively common (1 in 5). If autologous graft is not readily available, CryoVein is a safe alternative with similar perioperative outcomes.

Magnetic resonance imaging insights from active surveillance of women with ductal carcinoma in situ.

New approaches are needed to determine which ductal carcinoma in situ (DCIS) is at high risk for progression to invasive ductal carcinoma (IDC). We retrospectively studied DCIS patients who declined surgery (2002-2019), and received endocrine therapy (ET) and breast MRI. Baseline MRI and changes at 3 months and 6 months were analyzed by recursive partitioning to stratify IDC risk. Sixty-two patients (63 DCIS; 1 bilateral) with a mean follow-up of 8.5 years were included. Fifty-one percent remained on active surveillance (AS) without evidence of IDC, with a mean duration of 7.6 years. A decision tree based on MRI features of lesion distinctness and background parenchymal enhancement (BPE) at baseline and change after 3 months of ET stratified patients into low, intermediate, and high risk for progression to IDC. MRI imaging features in patients treated with ET and undergoing AS, may help determine which DCIS lesions are at low versus high risk for IDC.

A phase II study of lapatinib and bevacizumab as treatment for HER2-overexpressing metastatic breast cancer.

Preclinical data have demonstrated that the combination of antihuman epidermal growth factor receptor-2 (anti-HER2) and antivascular endothelial growth factor (anti-VEGF)--targeted agents has antitumor activity; these data indicate certain patients with HER2-overexpressing breast cancer may derive clinical benefit from this combination. The purpose of this single-arm phase II study was to determine the efficacy and safety of the dual-targeting combination of lapatinib and bevacizumab. Women with HER2-overexpressing advanced breast cancer received 1,500 mg oral lapatinib daily plus 10 mg/kg IV bevacizumab every 2 weeks. The primary endpoint was progression-free survival (PFS) at week 12; secondary endpoints included overall tumor response rate (ORR), clinical benefit rate (CBR), duration of response, time-to-response, PFS, and safety. Circulating tumor cells (CTC) and circulating endothelial cells (CEC) were measured at baseline and during study treatment as potential response markers. Fifty-two patients with stage IV disease were enrolled. The 12-week investigator-assessed PFS rate was 69.2% (95% confidence interval [CI]: 54.9, 81.3). Median PFS was 24.7 weeks (95% CI: 20.4, 35.1), and the CBR was 30.8% (95% CI: 18.7, 45.1). Of 45 patients with measurable disease, 6 were determined to have a partial response per Response Evaluation Criteria in Solid Tumors (ORR: 13.3%; 95% CI: 5.1, 26.8). The most common adverse events (AEs) included diarrhea, rash, and fatigue; most of these were either grade 1 or 2. Clinical responses were correlated with decreases in CTC and CEC. Lapatinib plus bevacizumab was active in patients with HER2-overexpressing breast cancer. The AE profile of the combination was consistent with the known profiles for these agents.

Everolimus and its role in hormone-resistant and trastuzumab-resistant metastatic breast cancer.

Advances in targeted therapies have improved progression-free and overall survival in women with metastatic breast cancer; however, regardless of efficacy, resistance almost always occurs eventually. Upregulation of the PI3K/AKT/mTOR pathway, which promotes cell growth and proliferation, is a means of escaping responsiveness to hormone therapy in hormone receptor-positive disease, or trastuzumab in HER2-positive disease. Everolimus, an inhibitor of mTOR, has shown promise in early clinical trials in metastatic breast cancer and is currently being studied in larger Phase II and III clinical trials, combined with hormone therapy or trastuzumab with or without cytotoxic chemotherapy. In this article, we discuss the mechanistic and preclinical data for everolimus, efficacy and safety results of clinical trials, and the landscape looking forward.

Assessing the role of robotic proctectomy in obese patients: a contemporary NSQIP analysis.

Robotic proctectomy has become increasingly popular for both benign and malignant indications. The purpose of this study was to determine if the robotic approach has a distinct advantage over laparoscopy in obese patients, which has been suggested by previous subgroup analyses. We performed a retrospective review of 2016-2018 National Surgery Quality Improvement Program (NSQIP) data to compare outcomes between patients who underwent robotic versus laparoscopic proctectomy, stratified by Body Mass Index (BMI) subgroups. We also compared outcomes of converted minimally invasive proctectomy to planned open operations. Four thousand four hundred eighteen (69.3%) patients underwent laparoscopic proctectomy, and 1956 (30.7%) patients underwent robotic proctectomy. Robotic proctectomy was associated with a significantly lower conversion rate compared to laparoscopic proctectomy (5.1% vs 12.3%; p = 0.002), and this relationship was maintained on an adjusted model. Obese (BMI > 30) patients were more likely to require conversion in both laparoscopic and robotic groups with the greatest difference in the conversion rate in the obese subgroup. Patients who underwent conversion had higher composite morbidity compared to patients who underwent planned open operations (50.8% vs 41.3%; p < 0.001). And among patients with rectal cancer, robotic proctectomy was associated with a greater incidence of positive radial tumor margins compared to laparoscopic proctectomy (8.0% vs 6.4%; p = 0.039), driven primarily by the obese subgroup. Our study demonstrates that robotic proctectomy is associated with a 7% lower conversion rate compared to laparoscopy and that obese patients are more likely to require conversion than non-obese patients. Among obese patients with rectal cancer, we identified an increased risk of positive radial margins with robotic compared to laparoscopic proctectomy.

Identifying Good Candidates for Active Surveillance of Ductal Carcinoma In Situ: Insights from a Large Neoadjuvant Endocrine Therapy Cohort.

Ductal carcinoma in situ (DCIS) is a biologically heterogenous entity with uncertain risk for invasive ductal carcinoma (IDC) development. Standard treatment is surgical resection often followed by radiation. New approaches are needed to reduce overtreatment. This was an observational study that enrolled patients with DCIS who chose not to pursue surgical resection from 2002 to 2019 at a single academic medical center. All patients underwent breast MRI exams at 3- to 6-month intervals. Patients with hormone receptor-positive disease received endocrine therapy. Surgical resection was strongly recommended if clinical or radiographic evidence of disease progression developed. A recursive partitioning (R-PART) algorithm incorporating breast MRI features and endocrine responsiveness was used retrospectively to stratify risk of IDC. A total of 71 patients were enrolled, 2 with bilateral DCIS (73 lesions). A total of 34 (46.6%) were premenopausal, 68 (93.2%) were hormone-receptor positive, and 60 (82.1%) were intermediate- or high-grade lesions. Mean follow-up time was 8.5 years. Over half (52.1%) remained on active surveillance without evidence of IDC with mean duration of 7.4 years. Twenty patients developed IDC, of which 6 were HER2 positive. DCIS and subsequent IDC had highly concordant tumor biology. Risk of IDC was characterized by MRI features after 6 months of endocrine therapy exposure; low-, intermediate-, and high-risk groups were identified with respective IDC rates of 8.7%, 20.0%, and 68.2%. Thus, active surveillance consisting of neoadjuvant endocrine therapy and serial breast MRI may be an effective tool to risk-stratify patients with DCIS and optimally select medical or surgical management. Significance: A retrospective analysis of 71 patients with DCIS who did not undergo upfront surgery demonstrated that breast MRI features after short-term exposure to endocrine therapy identify those at high (68.2%), intermediate (20.0%), and low risk (8.7%) of IDC. With 7.4 years mean follow-up, 52.1% of patients remain on active surveillance. A period of active surveillance offers the opportunity to risk-stratify DCIS lesions and guide decisions for operative management.

Modulation of the immune microenvironment of high-risk ductal carcinoma in situ by intralesional pembrolizumab injection.

Ductal carcinoma in situ (DCIS) is a risk factor for the subsequent development of invasive breast cancer. High-risk features include age <45 years, size >5 cm, high-grade, palpable mass, hormone receptor negativity, and HER2 positivity. We have previously shown that immune infiltrates are positively associated with these high-risk features, suggesting that manipulating the immune microenvironment in high-risk DCIS could potentially alter disease progression. Patients with high-risk DCIS were enrolled in this 3 × 3 phase 1 dose-escalation pilot study of 2, 4, and 8 mg intralesional injections of the PD-1 immune checkpoint inhibitor, pembrolizumab. Study participants received two intralesional injections, three weeks apart, prior to surgery. Tissue from pre-treatment biopsies and post-treatment surgical resections was analyzed using multiplex immunofluorescence (mIF) staining for various immune cell populations. The intralesional injections were easily administered and well-tolerated. mIF analyses demonstrated significant increases in total T cell and CD8+ T cell percentages in most patients after receiving pembrolizumab, even at the 2 mg dose. T cell expansion was confined primarily to the stroma rather than within DCIS-containing ducts. Neither cleaved caspase 3 (CC3) staining, a marker for apoptosis, nor DCIS volume (as measured by MRI) changed significantly following treatment. Intralesional injection of pembrolizumab is safe and feasible in patients with DCIS. Nearly all patients experienced robust total and CD8+ T cell responses. However, we did not observe evidence of cell death or tumor volume decrease by MRI, suggesting that additional strategies may be needed to elicit stronger anti-tumor immunity.

Unifying the Hepatopancreatobiliary Surgery Fellowship Curriculum via Delphi Consensus.

BACKGROUND: Hepatopancreatobiliary (HPB) Fellowship training in the Americas consists of 3 distinctive routes with variable curricula: Surgical Oncology Fellowship via the Society of Surgical Oncology (SSO), Abdominal Transplant Surgery Fellowship via the American Society of Transplant Surgeons (ASTS), and HPB Fellowship via the Americas Hepato-Pancreato-Biliary Association (AHPBA). Our objective was to establish a pan-American consensus among HPB surgeons, surgical oncologists, abdominal transplant surgeons, and general surgery residency program directors (GSPDs) on a core knowledge curriculum for HPB fellowship, and to identify topics appropriate for general surgery residency and subspecialty beyond HPB fellowship. STUDY DESIGN: A 3-round modified Delphi process was used. Baseline statements were developed by the Education and Training Committee of the AHPBA, in collaboration with representatives of the SSO, ASTS, and GSPDs. The expert panel, consisting of members of the 3 societies together with GSPDs, rated the statements on a 5-point Likert scale and suggested editing or adding new statements. A statement was included in the final curriculum when Cronbach's alpha value was ≥ 0.8 and ≥ 80% of the panel agreed on inclusion. RESULTS: The response rate was 100% for the first round, and 98% for the second and third rounds. Eighty-nine of 138 proposed statements were included in the final HPB fellowship curriculum. Curricula for general surgery residency and subspecialty beyond HPB fellowship included 50 and 29 statements, respectively. CONCLUSIONS: A multinational consensus on core knowledge for an HPB fellowship curriculum was achieved via the modified Delphi method. This core curriculum may be used to standardize HPB fellowship training across different pathways in the Americas.

Retransplantation After Living Donor Liver Transplantation: Data from the Adult to Adult Living Donor Liver Transplantation Study.

BACKGROUND: The use of living donor liver transplantation (LDLT) for primary liver transplantation (LT) may quell concerns about allocating deceased donor organs if the need for retransplantation (re-LT) arises because the primary LT did not draw from the limited organ pool. However, outcomes of re-LT after LDLT are poorly studied. The purpose of this study was to analyze the Adult to Adult Living Donor Liver Transplantation Study (A2ALL) data to report outcomes of re-LT after LDLT, with a focus on long-term survival after re-LT. METHODS: A retrospective review of A2ALL data collected between 1998 and 2014 was performed. Patients were excluded if they received a deceased donor LT. Demographic data, postoperative outcomes and complications, graft and patient survival, and predictors of re-LT and patient survival were assessed. RESULTS: Of the 1065 patients who underwent LDLT during the study time period, 110 recipients (10.3%) required re-LT. In multivariable analyses, hepatitis C virus, longer length of stay at LDLT, hepatic artery thrombosis, biliary stricture, infection, and disease recurrence were associated with an increased risk of re-LT. Patient survival among re-LT patients was significantly inferior to those who underwent primary transplant only at 1 (86% versus 92%), 5 (64% versus 82%), and 10 years (44% versus 68%). CONCLUSIONS: Approximately 10% of A2ALL patients who underwent primary LDLT required re-LT. Compared with patients who underwent primary LT, survival among re-LT recipients was worse at 1, 5, and 10 years after LT, and re-LT was associated with a significantly increased risk of death in multivariable modeling (hazard ratios, 2.29; P < 0.001).