LncRNA Malat1 suppresses pyroptosis and T cell-mediated killing of incipient metastatic cells

The contribution of antitumor immunity to metastatic dormancy is poorly understood. Here we show that the long noncoding RNA Malat1 is required for tumor initiation and metastatic reactivation in mouse models of breast cancer and other tumor types. Malat1 localizes to nuclear speckles to couple transcription, splicing and mRNA maturation. In metastatic cells, Malat1 induces WNT ligands, autocrine loops to promote self-renewal and the expression of Serpin protease inhibitors. Through inhibition of caspase-1 and cathepsin G, SERPINB6B prevents gasdermin D-mediated induction of pyroptosis. In this way, SERPINB6B suppresses immunogenic cell death and confers evasion of T cell-mediated tumor lysis of incipient metastatic cells. On-target inhibition of Malat1 using therapeutic antisense nucleotides suppresses metastasis in a SERPINB6B-dependent manner. These results suggest that Malat1-induced expression of SERPINB6B can titrate pyroptosis and immune recognition at metastatic sites. Thus, Malat1 is at the nexus of tumor initiation, reactivation and immune evasion and represents a tractable and clinically relevant drug target.

Exploration of cancer associated fibroblasts phenotypes in the tumor microenvironment of classical and pleomorphic Invasive Lobular Carcinoma

As the second most common subtype of breast carcinoma, Invasive Lobular Carcinoma (ILC) microenvironment features have not been thoroughly explored. ILC has different histological subtypes and elucidating differences in their microenvironments could lead to a comprehensive development of cancer therapies. We designed a custom-made cancer associated fibroblast (CAFs) panel and used multiplex immunofluorescence to identify the differences in tumor microenvironment between Classic ILC and Pleomorphic ILC.

Materials and methods

Multiplex immunofluorescence were performed on formalin fixed paraffin embedded tissues using Opal-7 color kit. The antibodies used for phenotyping CAFs were Pan CK (AE1/AE3), CD45, A-SMA, FAP, S100, Thy-1 with optimized dilutions. The images were acquired and analyzed using Vectra 3.0 imaging system and InForm software respectively.

Results

We studied 19 different CAFs colocalized phenotypes in the tumor, stroma and overall tissue compartments between classic and pleomorphic ILC. Total A-SMA+, A-SMA+FAP+S100+ and A-SMA+S100+ CAFs demonstrated higher densities in classic ILC cases while FAP+S100+ and S-100+ CAFs were increased in the pleomorphic subtype samples.

Conclusion

Our study explores multiple CAFs phenotypes between classical and pleomorphic ILC. We showed that CAFs subset differ between Classic ILC and Pleomorphic ILC. A-SMA CAFs are more prevalent in the TME of classic ILCs whereas Pleomorphic ILCs are dominated by CAFs without A-SMA expression. This also iterates the importance of exploring this particular type of breast carcinoma in more detail, paving the way for meaningful translational research.

PTEN in triple-negative breast carcinoma: protein expression and genomic alteration in pretreatment and posttreatment specimens

Background

Recent advances have been made in targeting the phosphoinositide 3-kinase pathway in breast cancer. Phosphatase and tensin homolog (PTEN) is a key component of that pathway.

Objective

To understand the changes in PTEN expression over the course of the disease in patients with triple-negative breast cancer (TNBC) and whether PTEN copy number variation (CNV) by next-generation sequencing (NGS) can serve as an alternative to immunohistochemistry (IHC) to identify PTEN loss.

Methods

We compared PTEN expression by IHC between pretreatment tumors and residual tumors in the breast and lymph nodes after neoadjuvant chemotherapy in 96 patients enrolled in a TNBC clinical trial. A correlative analysis between PTEN protein expression and PTEN CNV by NGS was also performed.

Results

With a stringent cutoff for PTEN IHC scoring, PTEN expression was discordant between pretreatment and posttreatment primary tumors in 5% of patients (n = 96) and between posttreatment primary tumors and lymph node metastases in 9% (n = 33). A less stringent cutoff yielded similar discordance rates. Intratumoral heterogeneity for PTEN loss was observed in 7% of the patients. Among pretreatment tumors, PTEN copy numbers by whole exome sequencing (n = 72) were significantly higher in the PTEN-positive tumors by IHC compared with the IHC PTEN-loss tumors (p < 0.0001). However, PTEN-positive and PTEN-loss tumors by IHC overlapped in copy numbers: 14 of 60 PTEN-positive samples showed decreased copy numbers in the range of those of the PTEN-loss tumors.

Conclusion

Testing various specimens by IHC may generate different PTEN results in a small proportion of patients with TNBC; therefore, the decision of testing one versus multiple specimens in a clinical trial should be defined in the patient inclusion criteria. Although a distinct cutoff by which CNV differentiated PTEN-positive tumors from those with PTEN loss was not identified, higher copy number of PTEN may confer positive PTEN, whereas lower copy number of PTEN would necessitate additional testing by IHC to assess PTEN loss.

Trial registration

NCT02276443.

Predictive Roles of Baseline Stromal Tumor-Infiltrating Lymphocytes and Ki-67 in Pathologic Complete Response in an Early-Stage Triple-Negative Breast Cancer Prospective Trial

High stromal tumor-infiltrating lymphocytes (sTILs) are associated with improved pathologic complete response (pCR) in triple-negative breast cancer (TNBC). We hypothesize that integrating high sTILs and additional clinicopathologic features associated with pCR could enhance our ability to predict the group of patients on whom treatment de-escalation strategies could be tested. In this prospective early-stage TNBC neoadjuvant chemotherapy study, pretreatment biopsies from 408 patients were evaluated for their clinical and demographic features, as well as biomarkers including sTILs, Ki-67, PD-L1 and androgen receptor. Multivariate logistic regression models were developed to generate a computed response score to predict pCR. The pCR rate for the entire cohort was 41%. Recursive partitioning analysis identified ≥20% as the optimal cutoff for sTILs to denote 35% (143/408) of patients as having high sTILs, with a pCR rate of 59%, and 65% (265/408) of patients as having low sTILs, with a pCR rate of 31%. High Ki-67 (cutoff > 35%) was identified as the only predictor of pCR in addition to sTILs in the training set. This finding was verified in the testing set, where the highest computed response score encompassing both high sTILa and high Ki-67 predicted a pCR rate of 65%. Integrating Ki67 and sTIL may refine the selection of early stage TNBC patients for neoadjuvant clinical trials evaluating de-escalation strategies.

Prevalence of rectus diastasis is higher in patients with inguinal hernia

PURPOSE

To determine the prevalence of rectus diastasis (RD) in patients with inguinal hernia.

MATERIAL AND METHODS

Multicenter, cross-sectional study. Patients with inguinal hernia were included in the study group (IH) and those with benign proctologic complaints created the control group (CG). Age, gender, BMI, family history for inguinal hernias, comorbid diseases, alcohol use, smoking, constipation, malignancy, chemotherapy, number of births, multiple pregnancies and prostate hypertrophy history of all patients in both groups were recorded. All patients were evaluated for RD and umbilical hernias by physical examination.

RESULTS

A total of 528 consecutive patients were included in the study (292 IH / 236 CG). Overall prevalence of RD was 35.6% and it was significantly higher in IH than in CG (46.9% vs 21.6%, p < 0.001). Also, umbilical hernia was more frequently detected in the patients with inguinal hernia. Other risk factors for RD were age, BMI, DM, BPH and smoking. The mean inter-rectus distance for 528 patients was 18.1 mm; it was 20.71 ± 10.68 mm in IH and 14.88 ± 8.82 in CG (p < 0.001). It was determined that the increase in age and BMI caused an increase in the inter-rectus distance, and that the presence of DM, inguinal hernia and umbilical hernia increased the inter-rectus distance quantitatively.

CONCLUSIONS

The prevalence of RD seems to be higher in patients with inguinal hernia comparing to that in general population. Increased age, high BMI and DM were found to be independent risk factors for RD development.

Does onlay mesh placement in emergency laparotomy prevent incisional hernia? A prospective randomized double-blind study

PURPOSE

The objective of this study is to assess the effectiveness and safety of onlay mesh closure of emergency midline laparotomy to prevent incisional hernia.

METHODS

This is a prospective randomized double-blind study and was carried out in the General Surgery Clinic, Konya City Hospital, from August 1, 2020 to August, 1, 2021. The study included 108 patients who were randomly grouped in 2 groups: patients with conventional abdominal closure and closure using additional onlay mesh (1:1). The follow-up period was for a year. The primary outcome was the incidence of incisional hernia and secondary outcomes were clinical data like complications, hospital length of stay, re-operations.

RESULTS

It was observed that incisional hernia was present in 14 patients (27.4%) in conventional abdominal closure group and was in 2 patients using mesh (4%), (p = 0.001). Clavien-Dindo 3B complications were in rise in conventional closure group (p = 0.02). Of all complications, burst abdomen was significantly more common in conventional closure group (p = 0.04). The rate of surgically treated complications were higher in conventional closure group (p = 0.02). Clavien-Dindo 3A complications were more common in patients with contaminated wound in mesh group (p = 0.02).

CONCLUSION

The use of mesh while closing the abdomen in emergency midline laparotomy reduces the risk of incisional hernia. Thus, to lower the risks of incisional hernia and its complications, prophylactic mesh can be used in high-risk patients.

Abstract P2-21-07: Exploring spatial correlations in Breast invasive Lobular Carcinoma subtypes using a novel CAF multiplex immunofluorescence panel

Background: Recent advances in immunotherapy led to development of new technologies to identify topographical distributions and correlations in the tumor microenvironment, enabling a better understanding of the tumor immune landscape. Based on the 2019 WHO classification Invasive lobular carcinoma (ILC) has various histological presentations. The pleomorphic variant has been reported to be biologically different to the classical counterpart. Cancer associated fibroblasts (CAFs) secrete cytokines and growth factors aiding in tumor growth. CAFs have been shown to express alpha-smooth muscle actin (α-SMA), Thy1, fibroblast activation protein (FAP), S-100. IHC based studies have shown differences in CAFs subpopulation between ILC and IDC. Here, we explored different CAFs subpopulations between Pleomorphic and Classical ILC using multiplex immunofluorescence (mIF).

Study design: Multiplex immunofluorescence (mIF) was performed on formalin-fixed paraffin-embedded (FFPE) tissue sections [(n=6, classic ILC; n=6 pleomorphic ILC)] stained with Opal 7-color Kit using an automated system. Sections were stained consecutively with Pancytokeratin, CD45, A-SMA, FAP, S100, Thy-1. Slides were scanned using the Vectra 3.0 spectral imaging system (PerkinElmer). Five tumor ROIs were examined with Phenochart (Akoya/PerkinElmer) viewer and subsequent images were analyzed to explore spatial distances of CK+ cells to the CAFs. Data was generated using InForm and Phenoptr softwares (Akoya Labs) as a median value. Statistical analysis data correlation was performed using SPSS version 24.0 (IBM Corp)

Results: Twelve invasive lobular carcinomas cases were evaluated. All cases with classical features were nuclear grade 2 and all pleomorphic cases (n=6) were nuclear grade 3. Six were Luminal B, five were Luminal A and one case was triple negative invasive lobular carcinoma. We studied nineteen different phenotypes of CAFs in the tumor, stroma, and overall tissue compartments. We found statistically significant differences (p-value&lt; 0.05) between the distances of CAFs from the tumor cells in classic and pleomorphic ILC in three phenotypes. The A-SMA+, A-SMA+/S100+ phenotypes were closer to the tumor cells in classic subtype and the S100 only phenotype was closer to the tumor cells in pleomorphic carcinomas. In addition, there were two other phenotypes namely A-SMA+/Thy-1+(closer to tumor cells in classic ILC) and FAP+/S-100+ (closer to tumor cells in pleomorphic ILC), which showed a trend of significance (Table 1)

Discussion: TME studies in invasive breast lobular carcinoma have been primarily based on chromogenic IHC. Multiplex immunofluorescence quantifies cell phenotype’s densities and positions in different tissue compartments (tumor vs stroma vs total tissue). Knowing the proximity of an individual TME cells to the tumor cells, aids in pinpointing possible therapeutic targets. Fibroblast dysregulation in cancers, enhances their pro-tumorigenic and anti-tumorigenic potential. Due to their heterogeneity, they can express a wide array of markers. Identifying the full possibility of CAF subsets is one of the keys to discovering actionable targets. Our results showed Alpha- SMA positive, Alpha-SMA/S-100 positive, Alpha SMA/Thy-1 positive CAFs in closer proximity to the classic ILC tumor cells as compared to pleomorphic ILC. Additionally, S-100 positive and FAP/S-100 positive CAFs showed a closer proximity to tumor cells in the pleomorphic subtype. Based on these results we hypothesize that pleomorphic ILCs are closely associated with pro-tumorigenic CAFs as compared to classic ILCs. Larger datasets are needed to confirm this. In conclusion we utilized an objective approach to quantify, phenotype and spatially correlate each cell in the tumor microenvironment. This has helped identifying CAFs subsets that differs in the spatial correlation to tumor cells in ILC subtypes, which can be potential actionable targets.

Table 1 Phenotypes of Cancer associated fibroblasts and their statistical correlation between classic vs pleomorphic invasive Lobular carcinomas.

Citation Format: Harsh Batra, Renganayaki K. Pandurengan, Heladio P. Ibarguen, Salome A McAllen, Qingqing Ding, Aysegul Sahin, Ignacio Wistuba, Edwin Roger Parra, Maria Gabriela Raso. Exploring spatial correlations in Breast invasive Lobular Carcinoma subtypes using a novel CAF multiplex immunofluorescence panel [abstract]. In: Proceedings of the 2022 San Antonio Breast Cancer Symposium; 2022 Dec 6-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2023;83(5 Suppl):Abstract nr P2-21-07.

Immunohistochemical expression of TRPS1 in mammary Paget disease, extramammary Paget disease, and their close histopathologic mimics

BACKGROUND

Trichorhinophalangeal syndrome type 1 (TPRS1) expression has been found to be highly sensitive and specific for breast carcinomas. The frequency of TRPS1 expression in cutaneous neoplasms such as mammary Paget disease (MPD) and extramammary PD (EMPD) is currently unknown. We assessed the utility of TRPS1 immunohistochemistry (IHC) in the evaluation of MPD, EMPD, and their histopathologic mimics, squamous cell carcinoma in situ (SCCIS) and melanoma in situ (MIS).

METHODS

Twenty-four MPDs, 19 EMPDs, 13 SCCISs, and 9 MISs were subjected to immunohistochemical analysis using anti-TRPS1 antibody. The intensity (none, 0; weak, 1⁺ ; moderate, 2⁺ ; strong, 3⁺ ) and proportion (<1%, absent; 1%-25%, focal; 26%-75%, patchy; >75%, diffuse) of TRPS1 expression were recorded. Relevant clinical data were documented.

RESULTS

TPRS1 expression was present in 100% (24/24) of MPDs, with 88% (21/24) of MPDs exhibiting strong, diffuse immunoreactivity. Sixty-eight percent (13/19) of EMPDs showed TRPS1 expression. Intriguingly, EMPDs lacking TRPS1 expression were consistently of perianal origin. TRPS1 expression was seen in 92% (12/13) of SCCISs but was absent in all MISs.

CONCLUSIONS

TRPS1 may be useful to distinguish MPDs/EMPDs from MISs, but its utility is limited in distinguishing them from other pagetoid intraepidermal neoplasms such as SCCISs.

P-125 INCIDENCE OF DIASTASIS RECTI ABDOMINIS SEEMS TO BE HIGHER IN PATIENTS WITH INGUINAL HERNIAS

Aim

To find the incidence of Diastasis Recti Abdominis (DRA) in patients with inguinal hernias.

Materials and Methods

Prospective, multicenter, cross-sectional study. Patients with inguinal hernias constitues the study group (IH), and patients with proctological disorders in the control group (PC). Investigated parameters: age, gender, BMI, family history, systemic comorbidities, alcohol consumption, tobacco use, constipation, malignancies, chemotherapy, number of births, multiple pregnancies, prostate hypertrophy. The measurements were done at 3 cm above the umbilicus. Any separation ≥20 mm was accepted as DRA. The existence of paraumbilical hernia (PUH)was also recorded.

Results

36 female and 212 male patients with a mean age of 51.3± 1.4 in IH, whereas 137 women and 305 men with a mean age of 44.5±15.9 in PC. 48.0% of IH and 21.1% of PC were diagnosed with DRA (p=0.001). Incidences of PU were 16.5% and %5.2 respectively (p=0.01). BMI ≥25, chronic pulmonary disease, multiple pregnancies and prostatic enlargement were associated with DRA. Multivariate analysis revealed that inguinal hernia and multiple pregnancies were independent factors for DRA.

Conclusions

Incidences of DRA and PUH seem to be higher in patients with inguinal hernias in comparison with control subjects.

P-019 BIOELECTRIC IMPEDANCE ANALYSIS TO DETERMINE THE RISK FACTORS FOR INGUINAL HERNIA

Aim

To search the risk factors for inguinal hernia development by performing bioelectrical impedance analysis.

Material & Methods

Prospective, multicenter, cross-sectional study. Patients with inguinal hernias constitues the study group (IH), and patients who admitted with other surgical problems in the control group (SC). Age, gender, and BMI of the patients were recorded. Body composition measurements were done by bioelectrical impedance analysis. The relations between the obtained parameters and inguinal hernia were evaluated.

Results

9 female and 125 male patients with a mean age of 53.4± 15.4 in IH, whereas 44 women and 24 men with a mean age of 44.5±15.9 in (SC). There were statistically significant differences between two groups regarding BMI, total body fat, lean abdominal muscle mass, abdominal fat amount, and visceral fat rates. Male gender, low total body fat rate, low total body fat amount, low lean body mass rate, and low visceral fat rate were determined as risk factors for inguinal hernia in univariate analysis. Only low total body fat rate was found to be an independent risk factor.

Conclusions

Low total body fat rate is an independent risk factor for inguinal hernia development.

Abstract 515: Single-cell transcriptomic analysis of HR+/HER2- breast cancer identifies gene signatures that predict outcomes of luminal A and B subtypes

Introduction: Patients with luminal A and B early-stage ER+/HER2- breast cancer (BrCa) are uniformly treated with adjuvant endocrine therapy (ET) (±chemotherapy). A better understanding of drivers of ET resistance is required as subsequent lethal metastatic disease remains a major clinical problem. Therefore, there is an unmet clinical need to identify biomarkers that select low- and high-risk patients who may benefit from de-escalation of current treatments or alternative therapeutic interventions. In the present study, we hypothesized that while luminal A and B tumors both arise from normal hormone-responsive cells, they are transcriptionally distinct, hence allowing the identification of unique gene signatures that can predict outcomes in each subtype.

Methods: Tumors from 10 early-stage ER+/HER2- BrCa patients were subjected to single-cell RNA-sequencing (scRNA-seq) analysis (10X Genomics); 6/10 tumors were classified as luminal A and 4/10 as luminal B based on combined PAM50 and immunohistochemical classification (Ki67 cut-off=20%). We performed a direct transcriptional comparison between luminal A and B tumors, using well-established signatures and unbiased differential gene expression analysis. To identify unique luminal A and B tumor-specific genes, we compared the gene expression profile of each luminal subtype with 10 non-neoplastic breast tissues. A predictive model (LASSO) was applied to select genes with the highest frequency using a training dataset. This resulted in 5- and 4-gene signatures for luminal A and B, respectively, which were used to calculate risk scores that divided each subtype into low- and high-risk groups. The prognostic value of the above signatures was validated in an independent dataset.

Results: The integrated scRNA-seq analysis of luminal A and B tumors revealed transcriptionally distinct tumor cell clusters while tumor microenvironment (TME) clusters were well intermixed. Luminal B tumors had higher cell cycle and BrCa-specific scores, low ER pathway-gene expression scores, and increased 8q amplifications. IFNγ, OXPHOS, p53, hypoxia and MYC targets were the most upregulated pathways in the luminal B subtype. The TME of luminal B tumors was comprised of lower CD4+ and CD8+ T cell but higher Treg levels. Comparison with normal breast tissues revealed that early-stage ER+ BrCa arises from hormone-responsive epithelial cells and provided a number of tumor-specific genes that were used to generate prognostic signatures. These signatures were capable of differentiating high- from low-risk patients within each subtype and predicting survival outcomes in two large-scale training and validation cohorts.

Conclusions: We developed a novel prognostic tool that can be used to determine duration of adjuvant ET and/or new therapeutic strategies for high-risk luminal A and B patients in the early-stage ER+/HER2- setting.

Citation Format: Sofia Mastoraki, Jerome Lin, Xiayu Rao, Sophie R. Liu, Harsh Batra, Maria G. Raso, Edwin R. Parra Cuentas, Akshara S. Raghavendra, Komal S. Rasaputra, Min Yi, Jing Wang, Aysegul Sahin, Debasish Tripathy, Kelly K. Hunt, Nicholas E. Navin, Khandan Keyomarsi. Single-cell transcriptomic analysis of HR+/HER2- breast cancer identifies gene signatures that predict outcomes of luminal A and B subtypes [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr 515.

Abstract 1798: Mechanisms of acquired resistance to palbociclib reveals pathways of response to abemaciclib

Background: CDK4/6 inhibitors (CDK4/6i) plus endocrine therapy (ET) delay progression and improve survival in patients with hormone receptor positive (HR+), HER2 negative metastatic breast cancer (MBC). However, most patients develop resistance to CDK4/6i leading to disease progression, thus new therapies to overcome resistance are needed. CDK4/6i [palbociclib (palbo), ribociclib (ribo), and abemaciclib (abema)] have the same nominal targets but vary in their target specificity and are pharmacologically distinct. Clinical benefit was observed in patients treated with abema after progression on a prior CDK4/6i suggesting that palbo/ribo refractory tumors retain abema sensitivity. We hypothesize that mechanisms driving acquired resistance to palbo and abema are distinct, and palbo-resistant models may be responsive to abema.

Models: 1) MCF-7 and T47D palbo and abema resistant cells, 2) patient derived xenografts (PDX) established from patients who progressed on ET alone (ET-resistant) or palbo + ET (palbo-resistant), 3) organoids derived from the palbo-resistant PDX, and 4) a HR+/HER2- MBC patient cohort who received abema after progression on palbo therapy.

Results: RNA-sequencing and proteomic analysis revealed that palbo and abema resistant cells exhibit more than 30 differentially altered pathways. EMT, IL6/STAT3, and CSC pathways were upregulated only in palbo-resistant cells, but not in abema-resistant cells. Palbo-resistant cells also showed upregulation of G2M/Mitotic spindle and downregulation of ER pathways, whereas abema-resistant cells displayed downregulation of G2M/Mitotic spindle and upregulation of ER pathways. Mechanistic analysis revealed that palbo-resistant cells are responsive to abema with a delay in doubling time and a reduction of the proliferation marker pHH3. Further, cells accumulated in the G2M-phase with concomitant high phospho-(Y15)-CDK1 and cyclin B levels. Organoid cultures generated from palbo-resistant PDX were sensitive to abema. Likewise, abema significantly delayed the tumor growth of palbo-resistant PDX, correlating in vivo with ex vivo treatments. Moreover, we assessed response to abema after progression on palbo in the ET-resistant PDX model (CDK4/6 sensitive) demonstrating a continued survival benefit from abema treatment compared to palbo. Clinical outcome analyses of a MBC patient cohort treated with abema following prior CDK4/6i showed a median progression free survival (PFS) of 6.3 months in those treated sequentially vs a PFS of 4.0 months in non-sequential treated patients.

Conclusion: Differential mechanism underlying palbo and abema acquired resistance can be exploited to overcome CDK4/6i resistance. These results provide rationale for clinical trials evaluating the benefit of abema treatment following progression on a prior CDK4/6i.

Citation Format: Juliana Navarro-Yepes, Nicole M. Kettner, Tuyen Bui, Akshara S. Raghavendra, Xiayu Rao, Jing Wang, Aysegul Sahin, Senthil Damodaran, Debasish Tripathy, Kelly K. Hunt, Khandan Keyomarsi. Mechanisms of acquired resistance to palbociclib reveals pathways of response to abemaciclib [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr 1798.

AB1387 THE EFFECTS OF PREGNANCY AND FERTILITY ON DRUG USAGE AND PREFERENCES IN RHEUMATOLOGICAL DISEASES: A SINGLE CENTER EXPERIENCE

Background

Rheumatological diseases usually affect women of reproductive age. Although the effects of these diseases on pregnancy vary; Joint and organ damage that may occur should be prevented, maternal and fetal effects of the treatment should be evaluated (1).

Objectives

The aim of this study to determine the effects of rheumatological diseases and drugs used on pregnancy and fertility.

Methods

Between January 2014 and January 2021, women between the ages of 18-45 who were diagnosed and treated at Cumhuriyet University Medical Faculty Rheumatology-Internal Medicine Department were retrospectively analyzed.

Results

The median age of the patients is 37 (min 19-max 45) years. 517 patients (51,7%) were pregnant after diagnosis, 39 patients (3,9%) had abortion after diagnosis, 957 patients (95,7%) had live birth, 69 patients (6,9%) had curettage, 43 patients (4,3%) could not have children. The median of pregnancies before diagnosis is 2 (min 1-max 11) the median of pregnancies after diagnosis is 1 (min 1-max 6) the median of abortions before diagnosis is 2 (min 1-max 7) the median of abortions after diagnosis is 1 (min. 1-max 4) the median of curettage is 1 (min 1-max 3) the median of live births is 2 (min 1-max 5). The distribution of patients according to drug use and drug used during pregnancy is shown in Figure 1. The distribution of the patients according to the diagnosis and the factors affecting pregnancies after diagnosis, abortions after diagnosis, curettage and live birth is shown in Table 1.

Table 1.

The distribution of the patients according to the diagnosis and the factors affecting pregnancies after diagnosis, abortions after diagnosis, curettage and live birth.

†FMF‡RA¶AS§PSASarcoidosisGranulomatous MastitisMyositisVasculitisBehçet’s DiseaseStill’s SyndromeGoutFibromyalgia††SLESjögren’s SyndromeSystemic Sclerosis‡‡APSAvaliable (%n)224 %22.4197 %19.7274 %27,459 %5,91 %0,1117 %0,7169 %16,93 %0,32146 %14,6105 %10,56037 %3,729 %2,9%0,1%0,1%0,2%6Not Avaliable (%n)776803 %80,3726 %72,6941 %94,1999 %99,9999 %99,9999 %99,9993 %99,3831 %83,1997 %99,7998 %99,8854 %99,9895 %89,5940 %94963 %96,3971 %97,1%77,6Total (%n)1000 %1001000 %1001000 %1001000 %1001000 %1001000 %1001000 %1001000 %1001000 %1001000 %1001000 %1001000 %1001000 %1001000 %1001000 %1001000 %100Use of colchicineUse of anakinraUse of methorexateUse of leflunomide(*OR %95 confidence range)(*OR %95 confidence range)(*OR %95 confidence range)(*OR %95 confidence range)**p value**p value**p value**p valueNumber of pregnancy after diagnosis*OR:1,58 (1,22-2,034)*OR:6,69 (1,51-29,60)*OR: - 0,73 (0,51-0,93)*OR: - 0,53 (0,30-0,93)**p: ‹0,001**p: ‹0,004**p: 0,05**p: 0,035‡‡APS (*OR %95 confidence range)††SLE (*OR %95 confidence range)**p value**p valueNumber of abortion*OR: 3,7 (1,68-8,43)*OR: 7,5 (2,78-20,25)after diagnosis**p: ‹0,001**p: 0,001‡‡APS (*OR %95 confidence range)**p valueNumber of curettage*OR: 5,5 (1,94-15,84) **p: 0,001Number of live birth*OR: - 0,20 (0,05-0,75) **p: 0,017

*OR: Odds Ratio

**p‹0,05 significant

†FMF: Family Mediterranean Fever

‡RA: Rheumatoid Arthritis

¶AS: Ankylosing Spondylitis

§PSA: Psoriatic Arthritis

††SLE: Systemic Lupus Erythematosus

‡‡APS: Anti Phospholipid Syndrome

Figure 1.

Distribution of patients according to drug use and drugs used during pregnancy

Conclusion

Women with rheumatic diseases should be in remission before pregnancy and should be followed closely throughout their pregnancy and treated with pregnancy-safe drugs. Preparations that can cause infertility in women during the reproductive period should not be used as much as possible. Patients should be informed in detail about the effects of their disease and the drugs used on pregnancy.

References

[1]Peterson E. A., Lynton J., Bernard A., Santillan M. K., Bettendorf B., Rheumatologic Medication Use During Pregnancy, Obstetrics & Gynecology: May 2020 - Volume 135 - Issue 5 - p 1161-1176doi: 10.1097/AOG.0000000000003755.

Acknowledgements

We would like to thank to Biostatistics Faculty Member Dr. Ziynet Çinar.

Disclosure of Interests

None declared

Clinical Outcomes Using Magnetic Seeds as a Non-wire, Non-radioactive Alternative for Localization of Non-palpable Breast Lesions

BACKGROUND

Nonpalpable breast lesions require precise preoperative localization to facilitate negative margins with breast-conserving therapy. The traditional use of wires has several challenges including patient discomfort, wire migration, and coordination of schedules between radiology and the operating room. Radioactive seed localization overcomes some of these challenges, but radiation safety requirements have limited adoption of this technology. The authors examined their institutional experience with Magseed as an alternative technology for localization and compared outcomes with those of wire and radioactive seed localization.

METHODS

An institutional review board (IRB)-approved retrospective study was performed to evaluate patients who underwent excisional biopsy or segmental mastectomy after wire-guided localization (WGL), radioactive seed localization (RSL), or Magseed localization (ML). The clinical and pathologic factors of the three groups were assessed with a negative margin rate as the primary outcome measure.

RESULTS

Of the 1835 patients in the study, 825 underwent WGL, 449 underwent RSL, and 561 underwent ML. For the patients with either multiple lesions or a large lesion that required bracketing, multiple localization devices were placed in 31% of the WGL patients, 28% of the RSL patients, and 23% of the ML patients (p = 0.006). Negative margins were achieved in 91% of the WGL patients, 89% of the RSL patients, and 89% of the ML patients (p = 0.4).

CONCLUSION

Localization of non-palpable breast lesions using Magseed is a safe and effective alternative to WGL and RSL that overcomes radiation safety limitations and increases radiology and surgery scheduling efficiency.

High-Grade Spindle Cell Lesions of the Breast: Key Pathologic and Clinical Updates

Most of the high-grade spindle cell lesions of the breast are malignant phyllodes tumors (MPTs), spindle cell carcinomas (SpCCs), and matrix-producing metaplastic breast carcinomas (MP-MBCs). MPTs have neoplastic spindle stromal cells and a classic leaf-like architecture with subepithelial stromal condensation. MPTs are often positive for CD34, CD117, and bcl-2 and are associated with MED12, TERT, and RARA mutations. SpCCs and MP-MBCs are high-grade metaplastic carcinomas, whereas neoplastic epithelial cells become spindled or show heterologous mesenchymal differentiation, respectively. The expression of epithelial markers must be evaluated to make a diagnosis. SAS, or rare metastatic spindle cell tumors, are seen in the breast, and clinical history is the best supporting evidence. Surgical resection is the standard of care.

Abstract P4-07-13: An exploratory case-control study of perineural invasion in breast cancer

Background: There is great interest in determining prognostic indicators in cancer as they enable more informed treatment decisions and patient counseling. Perineural invasion (PNI) has been established as a poor prognostic indicator in many types of cancer, however its significance in breast cancer is not clear. Research Objectives: The objective of this study was to explore the prognostic importance of PNI in breast cancer and identify clinicopathologic variables associated with PNI in breast cancer. Methods: A prospectively maintained database was used to identify patients treated at a single institution for stage I-III unilateral breast cancer from 2006-2014. PNI-positive cases included all patients whose tumors were reported to contain PNI in either the needle biopsy specimen or the surgical pathology, and each case was matched with two PNI-negative control patients on age, clinical stage, ER, PR, and HER2 status. A total of 492 patients were included in the analysis, including 164 PNI-positive patients and 328 control patients. Distributions of age, race, lymphovascular invasion, multifocality, clinical tumor size and pathologic tumor size were compared using Fisher’s exact test (categorical variables) or Wilcoxon rank-sum test (continuous variables). The method of Kaplan and Meier was used to estimate the distribution of overall survival, disease-free survival, and time to locoregional recurrence from the diagnosis date. All statistical tests used a significance level of 5%. No adjustments for multiple testing were made. Results: The median follow up was 6.26 years (6.3 years versus 6.2 years for PNI-positive and controls, respectively). The number of reported PNI-positive cases increased over the study period, with 76 cases reported during the 6-year period 2006-2011 and 88 cases reported during the last two years, 2013-2014. There was no statistical difference noted in overall survival, disease-free survival, or time to recurrence by clinical stage for PNI-positive patients compared to controls. It was noted that clinical stage 3 disease showed a trend toward poorer disease-free survival in PNI-positive patients although this did not reach statistical significance. Median pathologic tumor size was significantly higher in the PNI-positive patients compared to controls (2.2 cm versus 1.6 cm, respectively, p&lt;0.0001). In the subset of patients treated with neoadjuvant chemotherapy, median tumor size was also significantly higher in the PNI-positive patients compared to controls (2.8 cm versus 1.5 cm, p=0.0087). Pathologic node-positive status was more likely in the PNI-positive patients (47% versus 41%, p=0.019). Analysis of non-matched variables including race, lymphovascular invasion, multifocality and nuclear grade showed no statistically significant difference between the PNI and control groups.Conclusion: Perineural invasion was not found to be a statistically significant prognostic indicator of survival or locoregional recurrence. PNI is associated with larger pathologic tumor size, and this finding persists among patients treated with neoadjuvant chemotherapy. PNI is also associated with lymph node metastasis. This analysis is limited by small sample sizes and likely under reporting of PNI. Additional research is needed to evaluate the significance of PNI in breast cancer.

Table 1.Patient CharacteristicsVariableLevelsPNI (%)Control (%)P-ValueAge≤ 5047 (28.7)94 (28.7)p = 1.00&gt; 50117 (71.3)234 (71.3)RaceAsian10 (6.1)24 (7.3)p = 0.22Black9 (5.5)30 (9.2)Hispanic22 (13.4)51 (15.6)White122 (74.4)214 (65.2)Lymphovascular invasionY53 (32.3)80 (24.4)p = 0.07Lymphovascular invasionN111 (67.7)248 (75.6)p = 0.07MultifocalityN123 (75.0)206 (69.8)p = 0.28Y41 (25.0)89 (30.2)Nuclear Grade129 (18.4))47 (14.8)p = 0.28288 (55.7)166 (52.4)341 (25.9)104 (32.8)Clinical StageIA55 (33.5)110 (33.5)p = 1.00IIA59 (36.0)118 (36.0)IIB23 (14.0)46 (14.0)IIIA6 (3.7)12 (3.7)IIIB14 (8.5)28 (8.5)IIIC7 (4.3)14 (4.3)Pathologic N StageNx2 (1.2)1 (0.3)p = 0.019N083 (51.5)193 (59.0)N149 (30.4)88 (26.9)N217 (10.6)22 (7.0)N310 (6.2)23 (7.0)ERNeg11 (6.7)22 (6.7)p = 1.00Pos153 (93.3)306 (93.30PRNeg19 (11.6)38 (11.6)p = 1.00Pos145 (88.4)290 (88.4)HER2Neg155 (94.5)310 (94.5)p = 1.00Pos9 (5.5)18 (5.5)Neoadjuvant ChemotherapyN121 (73.3)240 (73.2)p = 1.00Y44 (26.7)88 (26.8)Clinical tumor sizeRange (cm)0.15 - 9.800.50-10.00p = 0.0013Median (cm)2.453.00Pathologic tumor sizeRange (cm)0.02-15.000.00 - 20.00p &lt; 0.0001Median (cm)2.201.60Pathologic tumor size after neoadjuvant chemotherapyRange (cm)0.02-120.00-20p = 0.0087Median (cm)2.751.47

Citation Format: Solange Erlyn Cox, Roland Bassett, Min Yi, Aysegul Sahin, Mediget Teshome, Kelly Hunt, Catherine Akay. An exploratory case-control study of perineural invasion in breast cancer [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 P4-07-13.

Study of Aqueous Ecballium Elaterium as Fibrinolytic in The Rabbit Model of Intrapleural Empyema

Aims

We aimed to investigate of intrapleural use of ecballium elaterium (EE) in a rabbit model empyema.

Methods

An empyema was induced in 21 rabbits after inoculation of Staphylococcus aureus. Glucose levels, pH, lactate dehydrogenase levels, and amounts of pleural drainage were evaluated in addition to pleural and empyema scores. The rabbits were divided into three groups, each 7, the isotonic solution, the streptokinase, and the ecballium group.

Results

At autopsy, there was no difference in pH, glucose, and LDH levels in three groups. The mean pleural drainage was greater in the ecballium group. A significant difference was detected between groups in terms of drainage amounts and pleural and empyema scores (P < 0.05). A significant difference in pleural and empyema scores was detected in the ecballium and streptokinase groups (P < 0.05). EE group had significant differences in drainage amounts and plural and empyema scores regard to the control group (P < 0.05). No significance was found between streptokinase and EE groups.

Conclusion

We conclude that intrapleural use of EE is at least as effective as streptokinase for the treatment of empyema.

The opioid peptide biphalin modulates human corneal epithelial wound healing in vitro

PURPOSE

Analgesic drugs, including nonselective opioids and non-steroidal anti-inflammatory drugs, should be used with great precautions to relieve pain after trauma to the corneal epithelium because of their unfavorable effects on wound healing. Biphalin is a synthetic opioid peptide that has been demonstrated to possess a strong analgesic effect on rodents. The purpose of this study is to investigate the effects of biphalin on human corneal epithelial wound healing.

METHODS

An immortalized human corneal epithelial cell (HCEC) culture was used to analyze the effects of biphalin on wound healing. The toxicity of biphalin at various concentrations was measured by the MTT assay. The effects of 1μM and 10μM biphalin on wound closure, cell migration and proliferation were tested in an in vitro scratch assay of HCECs. Naloxone, a non-selective competitive opioid receptor antagonist, was also used to inhibit the effects of biphalin in all experiments.

RESULTS

Biphalin did not cause any toxic effect on HCECs at concentrations lower than 100μM at various incubation time points. Biphalin significantly increased wound healing at 1μM concentration in an in vitro scratch assay of HCECs (P<0.05). It also significantly increased migration of HCECs (P<0.01). There was no significant difference between the biphalin and control groups of HCECs in the Ki67 proliferation assay.

CONCLUSION

Biphalin, which is a synthetic opioid peptide, promotes corneal epithelial wound healing by increasing cell migration. This role should be evaluated in further in vivo and clinical studies.

Cytoplasmic Cyclin E Expression Predicts for Response to Neoadjuvant Chemotherapy in Breast Cancer

BACKGROUND

Pathologic complete response (pCR) has been shown to be associated with favorable outcomes in breast cancer. Predictors of pCR could be useful in guiding treatment decisions regarding neoadjuvant therapy. The objective of this study was to evaluate cyclin E as a predictor of response to neoadjuvant chemotherapy in breast cancer.

METHODS

Patients (n = 285) with stage II-III breast cancer were enrolled in a prospective study and received neoadjuvant chemotherapy with anthracyclines, taxanes, or combination of the two. Pretreatment biopsies from 190 patients and surgical specimens following chemotherapy from 192 patients were available for immunohistochemical analysis. Clinical and pathologic responses were recorded and associated with presence of tumor infiltrating lymphocytes, cyclin E, adipophilin, programmed cell death-ligand 1, and elastase staining and other patient, tumor and treatment characteristics.

RESULTS

The pCR rate was significantly lower in patients with cytoplasmic cyclin E staining compared with those who had no cyclin E expression (16.1% vs 38.9%, P = 0.0005). In multivariable logistic regression analysis, the odds of pCR for patients who had cytoplasmic negative tumors was 9.35 times (P value < 0.0001) that compared with patients with cytoplasmic positive tumors after adjusting for ER, PR, and HER2 status. Cytoplasmic cyclin E expression also predicts long-term outcome and is associated with reduced disease free, recurrence free, and overall survival rates, independent of increased pretreatment tumor infiltrating lymphocytes.

CONCLUSIONS

Cyclin E independently predicted response to neoadjuvant chemotherapy. Hence, its routine immunohistochemical analysis could be used clinically to identify those breast cancer patients expected to have a poor response to anthracycline/taxane-based chemotherapy.

AB0893-HPR TREATMENT SATISFACTION, EXPECTATIONS, PATIENT PREFERENCES, AND CHARACTERISTICS IN PATIENTS WITH RHEUMATOID ARTHRITIS (RA): TURKISH COHORT RESULTS OF THE SENSE STUDY

Background:

Suboptimal control of RA may lead to severe and progressive articular damage, loss of function, and deterioration of the quality of life (QoL).

Objectives:

To assess treatment satisfaction, sociodemographic, clinical, health care resource utilization, and QoL characteristics of patients with sub-optimally controlled RA and treated with conventional synthetic and/or biologic DMARDs.

Methods:

This study was an international, multicenter, cross-sectional, non-interventional study. Adult RA patients with moderate to severe disease activity (DAS28>3.2) were enrolled. Patient satisfaction was evaluated with Treatment Satisfaction Questionnaire for Medication (TSQM, version 1.4) with a scale ranging from 0 (indicating poor satisfaction) to 100 (indicating perfect satisfaction). Patients were questioned regarding treatment adherence, patient preferences, and expectations. Workability was evaluated using Work Productivity and Activity Impairment Questionnaire-Rheumatoid Arthritis (WPAI-RA, version 2.0). Short Form 36 (V2) survey were performed to all patients.

Results:

One hundred sixty-four patients were included in the study and most (78.0%) were female. The median age was 57.0 years, ranging between 22.0 and 84.0 years. Half of the patients (50.6%) were primary school graduates and 6.1% were unemployed due to RA and seeking work. Median time since RA diagnosis was 8.0 years and mean (±SD) DAS28-CRP score was 4.8 (±1.0). Mean total activity impairment was 54.9% (±27.4). In the past 3 months from enrollment, the mean number of healthcare professional and emergency room visits were 1.8 (±1.1) and 1.8 (±1.3), respectively. Mean number and length of hospitalizations in the previous 3 months were 1.1 (±0.3) times and 8.3 (±7.2) days, respectively. Mean TSQM scores were 53.5 (±21.4) for effectiveness, 86.0 (±26.7) for side effects, 67.8 (±16.5) for convenience, and 57.7 (±22.0) for global satisfaction. The leading expectation was ‘lasting relief of RA symptoms’ (mean score: 5.8). Preferred time until the effect of onset was ‘up to 1 week’ for 76.2% of the patients. Most of the patients (57.9%) preferred oral administrations and the most preferred frequency of administration was ‘once per day’ (46.3%). Mean physical and mental component summary scores for Short Form 36 (V2) survey were 37.9 (±8.3) and 40.1 (±10.7).

Conclusion:

Two-thirds of the patients with RA who have suboptimal responses are not satisfied with their treatments. Moreover, oral and once-daily treatment approaches stand out in patient preferences. Finally, suboptimal control leads to deterioration in clinical characteristics, workability, and QoL of patients with RA.

Acknowledgements:

The design, study conduct, and financial support for the study were provided by AbbVie. AbbVie participated in the interpretation of data, review, and approval of the publication. All authors have received research funding for this study. The authors wish to thank B. Murat Ozdemir of Monitor CRO for medical editing and reviewing services of this manuscript. AbbVie provided funding to Monitor CRO for this work.

Disclosure of Interests:

Umut Kalyoncu Speakers bureau: AbbVie, Pfizer, UCB, Novartis, and Janssen, Consultant of: AbbVie, Pfizer, UCB, Novartis, and Lilly, Grant/research support from: AbbVie, Pfizer, and Janssen, Adem Kucuk Speakers bureau: AbbVie, Gokhan Sargin: None declared, Fatih Ozdener Speakers bureau: UCB, Nutricia Advanced Medical Nutrition, Grant/research support from: Nutricia Advanced Medical Nutrition, Servet Yolbaş Speakers bureau: AbbVie, UCB, Pfizer, and MSD, Berna Yurttas: None declared, Sezin Turan: None declared, Gezmiş Kimyon Speakers bureau: AbbVie, Amgen, Pfizer, Novartis, UCB, MSD, Johnson and Johnson, and Celltrion, Consultant of: Amgen, and Pfizer, ALI SAHIN Speakers bureau: Roche, Pfizer, and AbbVie, Consultant of: Roche and Pfizer, Sedat Yilmaz Speakers bureau: UCB, Pfizer, AbbVie, MSD, Novartis, and Celltrion, Consultant of: Pfizer and Novartis, Ridvan Mercan Speakers bureau: AbbVie, Novartis, MSD, Pfizer, UCB, Roche, Amgen, and Celltrion, Consultant of: Novartis, MSD, Pfizer, and Celltrion, Hakan Emmungil Speakers bureau: AbbVie, Pfizer, Novartis, and MSD, Muhammet Çinar Speakers bureau: AbbVie, Pfizer, Celltrion, UCB, Amgen, Novartis, and MSD, Grant/research support from: AbbVie, Pfizer, Celltrion, UCB, Amgen, Novartis, and MSD, İlhan Sezer Speakers bureau: AbbVie, Pfizer, MSD, Novartis, Celltrion, UCB, Amgen, and Abdi Ibrahim, Consultant of: AbbVie, Pfizer, MSD, Novartis, Celltrion, UCB, Amgen, and Abdi Ibrahim, Grant/research support from: AbbVie, Pfizer, MSD, Novartis, Celltrion, UCB, Amgen, and Abdi Ibrahim, Timuçin Kaşifoğlu Speakers bureau: AbbVie, Amgen, Roche, MSD, Novartis, Pfizer, and UCB, Consultant of: AbbVie, Amgen, Roche, MSD, Novartis, Pfizer, and UCB, Fulya Cosan Speakers bureau: AbbVie, Pfizer, Novartis, UCB, and MSD, Taskin Senturk: None declared, Nevsun Inanc Speakers bureau: AbbVie, UCB, Novartis, Pfizer, Roche, Lilly and MSD, Consultant of: Roche and Pfizer, Grant/research support from: Roche and Pfizer

Genomic, Transcriptomic, and Proteomic Profiling of Metastatic Breast Cancer

PURPOSE

Metastatic breast cancer (MBC) is not curable and there is a growing interest in personalized therapy options. Here we report molecular profiling of MBC focusing on molecular evolution in actionable alterations.

EXPERIMENTAL DESIGN

Sixty-two patients with MBC were included. An analysis of DNA, RNA, and functional proteomics was done, and matched primary and metastatic tumors were compared when feasible.

RESULTS

Targeted exome sequencing of 41 tumors identified common alterations in TP53 (21; 51%) and PIK3CA (20; 49%), as well as alterations in several emerging biomarkers such as NF1 mutations/deletions (6; 15%), PTEN mutations (4; 10%), and ARID1A mutations/deletions (6; 15%). Among 27 hormone receptor-positive patients, we identified MDM2 amplifications (3; 11%), FGFR1 amplifications (5; 19%), ATM mutations (2; 7%), and ESR1 mutations (4; 15%). In 10 patients with matched primary and metastatic tumors that underwent targeted exome sequencing, discordances in actionable alterations were common, including NF1 loss in 3 patients, loss of PIK3CA mutation in 1 patient, and acquired ESR1 mutations in 3 patients. RNA sequencing in matched samples confirmed loss of NF1 expression with genomic NF1 loss. Among 33 patients with matched primary and metastatic samples that underwent RNA profiling, 14 actionable genes were differentially expressed, including antibody-drug conjugate targets LIV-1 and B7-H3.

CONCLUSIONS

Molecular profiling in MBC reveals multiple common as well as less frequent but potentially actionable alterations. Genomic and transcriptional profiling demonstrates intertumoral heterogeneity and potential evolution of actionable targets with tumor progression. Further work is needed to optimize testing and integrated analysis for treatment selection.

Crossing mesh tails in the Lichtenstein repair method for medial (direct) inguinal hernia: recurrence and chronic pain rates after five years

PURPOSE

This study aimed to determine whether crossing of the mesh's lateral tails is beneficial in Lichtenstein repairs for medial (direct) inguinal hernias.

METHODS

We allocated 116 patients with unilateral medial (direct) inguinal hernias into two groups: mesh tail crossing (group C) or no mesh tail crossing (group N). In group C, the lateral tails were sutured together at the inguinal ligament, whereas the lateral tails were sutured in a parallel position in group N. Visual analog scale (VAS) scores were postoperatively recorded in person at the 1st, 7th, 30th, and 90th days and at the 1st year. The Short-Form Health Survey (SF-36) scores were calculated postoperatively at one month and one year. Examinations to detect hernia recurrence were performed at the end of the 1st year. Follow-ups at the 5th year were performed via phone calls to obtain the Sheffield pain scale and VAS values and to determine the possibility of hernia recurrence.

RESULTS

VAS and SF-36 scores at the 1st, 7th, 30th, and 90th days and 1st year were all higher in group C than in group N. In group C, one patient experienced moderate pain, and one experienced severe pain. In the 5th year, VAS and Sheffield pain scores were significantly higher in group C than in group N.

CONCLUSIONS

During Lichtenstein repair for medial (direct) inguinal hernias, crossing of the mesh tails may increase the frequency of postoperative chronic inguinal pain.

Abstract PS18-37: Loss of Trop2 protein in metaplastic carcinoma of breast by IHC

Background: Trop2 (trophoblast cell surface antigen) is a transmembrane calcium transducer which has been associated with tumor growth, aggressiveness and metastasis. Compared to normal tissue, Trop2 is expressed at much higher levels in many epithelial tumors, which makes it an excellent target for ADCs (antibody-drug conjugates). Sacituzumab govitecan-hziy, an ADC that combines Trop-2 antibody with a SN-38 payload has been recently approved for treatment of refractory metastatic triple-negative breast cancer, and several other TROP2 targeted therapies are in development. To better understand Trop 2 expression in breast tumor that may help to identify patients who could benefit most from Trop2-targeted therapy, we aimed to screen Trop2 protein in multiple types of breast tumor. Design: Using chromogenic immunohistochemistry (IHC), Trop2 protein was examined in 42 formalin fixed paraffin embedded (FFPE) specimens from surgically resected breast tumors, including 21 TNBC, 16 HR+, 4 HER2+ (3 HR+/HER2+ and 1 HR-/HER2+), and 1 sarcoma. Sections were stained on an automated staining system (BOND-MAX; Leica Microsystems) using anti-TROP2 antibody (clone ERP20043, Abcam, cat# 214488). Membrane staining was assessed. The percentage of positivity (0% to 100%) and the staining intensity (0 = no staining, 1+ = weak staining, 2+ = moderate staining, and 3+ = strong staining) were evaluated and multiplied to generate H-score (0-300). Results: Among of 41 breast carcinoma cases, 38 (92.6%) cases expressed Trop2 protein in tumor cells, with a median H-score of 162.5, including 18/21 TNBC, 16/16 HR+, 4/4 HER2+ cases. Trop2 was expressed in several breast cancer histopathology subtypes, including 32 invasive ductal carcinomas (H score ranged from 29 - 290), 2 invasive lobular carcinomas (H score 140 and 145), 1 invasive papillary carcinoma (H score 70), 1 invasive micropapillary carcinoma (H score 210), 1 invasive squamous cell carcinoma (H score 245) and 1 metaplastic carcinoma with mesenchymal differentiation (cartilaginous sarcomatoid type) (H score 17). Three breast carcinomas were negative for Trop2 (H score 0). All three cases are metaplastic carcinomas, including two spindle cell carcinomas and one with mesenchymal differentiation, which are TNBC. Only two of 5 (40%) metaplastic carcinomas tested expressed Trop2 (p = 0.0034). One breast sarcoma was tested and had no TROP2 expression. Conclusion: Trop2 is commonly expressed in breast cancer. However, metaplastic carcinoma of breast has shown a trend of Trop2 protein loss. Further validation on Trop2 loss in metaplastic carcinoma might help with identifying breast cancer patients less likely to benefit from Trop2-targeted therapy.

Citation Format: Fei Yang, Yasmeen Rizvi, Erkan Yuca, Ming Zhao, Kurt Evans, Xiaofeng Zheng, Aysegul Sahin, Funda Meric-Bernstam. Loss of Trop2 protein in metaplastic carcinoma of breast by IHC [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 PS18-37.