Benign Epithelium Research Articles

Case Report of Lipomyoma

Report: Uterine lipoleiomyoma are rare forms of leiomyomas that are often only described in literature as case reports. Lipoleiomyomas could increase in size despite menopause and most commonly occur in postmenopausal women with an incidence rate of 0.03% to 0.2% Clinical symptoms of lipoleiomyoma are very similar to leiomyoma. Radiologic imaging can aid in the diagnosis of lipoleiomyoma with smooth muscle confined to the tumor periphery. In our case, we describe a 53y/o G0P0 perimenopausal patient who complained of abnormal uterine bleeding with irregular menses, urinary retention and difficulty completely emptying her bladder due to the large mass compressing her bladder. She was diagnosed with a large 8.8 cm hyperechoic lesion with internal vascularity arising from the central uterus/ endometrium. Radiology recommended a pelvic MRI for further differentiation of mass. Office hysteroscopy with endometrial biopsy was performed. Pathology confirmed limited inactive endometrium, benign endometrial surface epithelium. The patient requested a hysterectomy through a minimally invasive gynecologic surgery approach. A pelvic MRI was performed that revealed a large, round, circumscribed mass measuring 7.3 X 7.2 X 7.5 cm favoring to represent an intramural lipoleiomyoma. The patient had a robotic assisted laparoscopic hysterectomy which was uncomplicated. Final histopathologic diagnosis was uterine lipomyoma. As benign masses, management for lipoleiomyoma are guided by symptoms, fertility preservation desires, and whether or not a patient is a candidate for surgical intervention. Given the rarity of these cases, the histogenesis is still relatively unknown although various theories exist such as differentiation of embryonic fat cells, metaplastic changes of existing cells into fat cells, and pluripotent cell migration. Although there was not evidence of malignancy in our case report, certain literature has suggested the presence of coexisting malignancies and in an even rarer occasion the presence of liposarcoma from a lipoleiomyoma. More information is needed on these rare cases in order to further lead management and any recommendations regarding cancer screening on top of age related recommendations already in place.

P300/CBP degradation is required to disable the active AR enhanceosome in prostate cancer.

Prostate cancer is an exemplar of an enhancer-binding transcription factor-driven disease. The androgen receptor (AR) enhanceosome complex comprised of chromatin and epigenetic coregulators assembles at enhancer elements to drive disease progression. The paralog lysine acetyltransferases p300 and CBP deposit histone marks that are associated with enhancer activation. Here, we demonstrate that p300/CBP are determinant cofactors of the active AR enhanceosome in prostate cancer. Histone H2B N-terminus multisite lysine acetylation (H2BNTac), which is exclusively reliant on p300/CBP catalytic function, marked active enhancers and was notably elevated in prostate cancer lesions relative to the adjacent benign epithelia. Degradation of p300/CBP rapidly depleted acetylation marks associated with the active AR enhanceosome, which was only partially phenocopied by inhibition of their reader bromodomains. Notably, H2BNTac was effectively abrogated only upon p300/CBP degradation, which led to a stronger suppression of p300/CBP-dependent oncogenic gene programs relative to bromodomain inhibition or the inhibition of its catalytic domain. In vivo experiments using an orally active p300/CBP proteolysis targeting chimera (PROTAC) degrader (CBPD-409) showed that p300/CBP degradation potently inhibited tumor growth in preclinical models of castration-resistant prostate cancer and synergized with AR antagonists. While mouse p300/CBP orthologs were effectively degraded in host tissues, prolonged treatment with the PROTAC degrader was well tolerated with no significant signs of toxicity. Taken together, our study highlights the pivotal role of p300/CBP in maintaining the active AR enhanceosome and demonstrates how target degradation may have functionally distinct effects relative to target inhibition, thus supporting the development of p300/CBP degraders for the treatment of advanced prostate cancer.

Deep learning detects premalignant lesions in the Fallopian tube

Tubo-ovarian high-grade serous carcinoma is believed to originate in the fallopian tubes, arising from precursor lesions like serous tubal intraepithelial carcinoma (STIC) and serous tubal intraepithelial lesion (STIL). Adequate diagnosis of these precursors is important, but can be challenging for pathologists. Here we present a deep-learning algorithm that could assist pathologists in detecting STIC/STIL. A dataset of STIC/STIL (n = 323) and controls (n = 359) was collected and split into three groups; training (n = 169), internal test set (n = 327), and external test set (n = 186). A reference standard was set for the training and internal test sets, by a panel review amongst 15 gynecologic pathologists. The training set was used to train and validate a deep-learning algorithm (U-Net with resnet50 backbone) to differentiate STIC/STIL from benign tubal epithelium. The model’s performance was evaluated on the internal and external test sets by ROC curve analysis, achieving an AUROC of 0.98 (95% CI: 0.96–0.99) on the internal test set, and 0.95 (95% CI: 0.90–0.99) on the external test set. Visual inspection of all cases confirmed the accurate detection of STIC/STIL in relation to the morphology, immunohistochemistry, and the reference standard. This model’s output can aid pathologists in screening for STIC, and can contribute towards a more reliable and reproducible diagnosis.

Immunohistochemical findings and clinicopathological features of breast cancers with pathogenic germline mutations in Non-BRCA genes

Deleterious germline mutations in multiple genes confer an increased breast cancer (BC) risk. Immunohistochemical (IHC) expression of protein products of mutated high-risk genes has not been investigated in BC. We hypothesized that pathogenic mutations may lead to an abnormal IHC expression pattern in the tumor cells. BCs with deleterious germline mutations in CHEK2, ATM, PALB2 &PTEN were identified. Immunohistochemistry was performed using Dako staining platform on formalin fixed paraffin embedded tumor tissue. Primary antibodies for PALB2 (ab202970), ATM [2C1(1A10)}, CHK2 (EPR4325), and PTEN (138G6) proteins were used for BCs with respective deleterious mutations. IHC expression was assessed in tumor and adjacent benign breast tissue. Total 27 BCs with 10 CHEK2, 9 ATM, 6 PALB2 & 2 PTEN deleterious germline mutations were identified. IHC staining was performed on 8 CHEK2, 7 ATM, 6 PALB2 & 2 PTEN cases. Abnormal CHEK2 IHC staining was identified in 7/8(88%) BCs. Three distinct CHK2 IHC patterns were noted: 1) Strong diffuse nuclear positivity (5 BC), 2) Null-pattern (2 BC), & 3) Normal breast–like staining in 1 BC Four of 5 (80%) strong CHK2 staining BC had missense CHEK2 mutations. Null-pattern was present with a missense & a frameshift mutation. Normal breast-like CHEK2 IHC staining pattern was present in 1 BC with CHEK2 frameshift mutation. Loss of nuclear/cytoplasmic PTEN IHC expression was noted in 2 in-situ carcinomas. Abnormal PTEN and CHK2 IHC were present in atypical ductal hyperplasia and flat epithelial atypia. ATM and PALB2 IHC expression patterns were similar in tumor cells and benign breast epithelium: mild to moderate intensity nuclear and cytoplasmic staining. We report abnormal CHEK2 IHC expression in 88% of BCs with pathogenic CHEK2 mutations. With PTEN and CHEK2 pathogenic mutations, abnormal IHC patterns are seen in early atypical proliferative lesions. IHC may be applied to identify CHEK2 &PTEN mutated BCs and precursor lesions.

Abstract 7064: BRCA 1/2 haploinsufficiency-associated metabolic dysfunction in benign fallopian tube epithelia

Abstract In 3-17% of women with BRCA1/2 mutations who undergo risk-reducing surgery, pre-neoplastic and neoplastic lesions are found in their fallopian tubes that display differential loss of heterozygosity of BRCA1/2. Precisely how mutations in BRCA1/2 predispose women to develop high grade serous ovarian carcinoma (HGSC) is not completely understood. Although linked to various processes localized in the nucleus, BRCA1/2 may also have essential roles in the cytoplasm, specifically in the regulation of key processes associated with mitochondrial homeostasis and metabolism. Understanding how haploinsufficiency of BRCA1/2 contributes to the potential neoplastic transformation of fallopian tube epithelial cells should reveal new insights into BRCA1/2 function, and ultimately provide novel opportunities for preventative interventions in individuals with this mutation and new treatment opportunities for HGSC associated with BRCA1/2 heterozygosity. We have identified distinct metabolic and mitochondrial deficits in BRCA2 mutation carriers compared to BRCA1 carriers and non-carriers. Fallopian tube epithelial cell lines derived from BRCA2 mutation carriers showed increased levels of mitochondrial respiration and activity followed by BRCA1 mutation carriers and non-carriers. Western blot analysis of mitochondrial proteins regulating glycolysis and oxidative phosphorylation showed differential expression based on mutation status. Transmission electron microscopy of BRCA2 mutation carriers showed increased disrupted mitochondrial networks when compared to wild type, suggesting that mutation status may contribute to increased mitochondrial fission. These observations reveal an entirely new aspect of BRCA1 and BRCA2 biology and further studies will disaggregate the effects of BRCA1 and BRCA2 on mitochondrial function, versus DNA damage repair. Ultimately, this work will provide new insight into the adaptive changes within FT cells which promote neoplastic transformation and inform how high-grade serous carcinoma (HGSC) cells distinctively respond to microenvironmental stimuli. Citation Format: Jovanka Ravix, Iru Paudel, Gauthami Pulivendala, Ramlogan Sowamber, Elizabeth Smith, Matthew Schlumbrecht, David Lombard, Sophia George. BRCA 1/2 haploinsufficiency-associated metabolic dysfunction in benign fallopian tube epithelia [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 7064.

Spatial MS multiomics on clinical prostate cancer tissues.

Mass spectrometry (MS) and MS imaging (MSI) are used extensively for both the spatial and bulk characterization of samples in lipidomics and proteomics workflows. These datasets are typically generated independently due to different requirements for sample preparation. However, modern omics technologies now provide higher sample throughput and deeper molecular coverage, which, in combination with more sophisticated bioinformatic and statistical pipelines, make generating multiomics data from a single sample a reality. In this workflow, we use spatial lipidomics data generated by matrix-assisted laser desorption/ionization MSI (MALDI-MSI) on prostate cancer (PCa) radical prostatectomy cores to guide the definition of tumor and benign tissue regions for laser capture microdissection (LCM) and bottom-up proteomics all on the same sample and using the same mass spectrometer. Accurate region of interest (ROI) mapping was facilitated by the SCiLS region mapper software and dissected regions were analyzed using a dia-PASEF workflow. A total of 5525 unique protein groups were identified from all dissected regions. Lysophosphatidylcholine acyltransferase 1 (LPCAT1), a lipid remodelling enzyme, was significantly enriched in the dissected regions of cancerous epithelium (CE) compared to benign epithelium (BE). The increased abundance of this protein was reflected in the lipidomics data with an increased ion intensity ratio for pairs of phosphatidylcholines (PC) and lysophosphatidylcholines (LPC) in CE compared to BE.

Abstract B065: Biomarker approach to define tumor subtype in pancreatic ductal adenocarcinoma

Abstract Background: Pancreatic ductal adenocarcinoma (PDAC) is one of the most lethal tumors with a predicted five-year survival rate in 2023 of 12%. Building on prior observations that molecular subtypes correlate with survival and response to treatment, our goal has been to understand the patterns of expression and prognostic correlations of three reciprocally expressed proteins previously identified as surrogate biomarkers of PDAC subtypes. Keratin 17 (K17) and Keratin 5 (K5) have both been identified as biomarkers of the basal subtype whereas GATA6, a transcription factor necessary for normal pancreatic development, is a surrogate marker of the classical subtype associated with longer-term survival. Here, we explore the expression of these three diagnostic biomarkers in PDAC and their specificity to tumor cells. Methods: Immunohistochemical analyses of K17 (KDx Diagnostics), GATA6 (R&D Systems), and KT5 (Leica) were performed on archival primary PDAC specimens from Stony Brook University Hospital (n= 30), by routine immunoperoxidase methods on serial sections. IHC stained slides were scanned using an Olympus VS200 slide scanner and images were imported into QuPath for digital analysis. Regions of interest (ROIs) were defined by the presence of tumor cells and were identified by histological assessment of representative sections. Digital scoring was performed on identified ROIs using the integrated "positive cell detection" function in QuPath and classified into three different stain intensities (1+, 2+, 3+). The threshold for each intensity is as follows: 1+, 0.2; 2+, 0.4; 3+, 1.0. According to the number of detections of each intensity, tumor cells were categorized into negative (0 and 1+) or positive (2+ and 3+). The percentage positive of analyzed biomarker expression within the tumor ROI was calculated by dividing the total number of positive cells by the total number of detected cells. Results: K17 was detected in both well and poorly differentiated PDAC components and in a few benign proliferative ducts of chronic pancreatitis but no staining was detected in stromal cells, benign ductal epithelium, or acinar cells. K5 was detected in a smaller proportion of cells from glandular components of the tumor as well as in most diffusely infiltrative single cells, benign ductal, and acinar cells but not in stromal cells. By contrast, GATA6 was detected in the nuclei of most cancer epithelial cells and was also detected in benign ductal cells, acinar cells, and stromal cells. The proportion of K17 expressing cells exceeded that of K5 positive cells in the great majority of ROIs and across cases. Conclusions: Keratin 17 detects a higher proportion of tumor cells than K5 and shows the lowest level of expression in benign cell types. By contrast, GATA6 IHC shows variable patterns of expression related to K17 or K5 expression and is expressed in the highest proportion of tumor cells, including both well-differentiated, diffusely infiltrative components, and benign tissue components. Citation Format: Carson Ho, Michael Horowitz, Lyanne Oblein, Shayan Sarkar, Soma Kobayashi, Karen Bai, Natalia Marchenko, Luisa Escobar-Hoyos, Kenneth Shroyer. Biomarker approach to define tumor subtype in pancreatic ductal adenocarcinoma [abstract]. In: Proceedings of the AACR Special Conference in Cancer Research: Pancreatic Cancer; 2023 Sep 27-30; Boston, Massachusetts. Philadelphia (PA): AACR; Cancer Res 2024;84(2 Suppl):Abstract nr B065.

SAT407 Hematospermia In Transgender Woman Revealing Occult Endometriosis

Abstract Disclosure: J.C. Coleman-Belin: None. T. Reisman: None. Background: While hematospermia (visible blood in ejaculate) is most frequently benign, etiology includes idiopathic, infection, prostate disease, iatrogenic, obstruction, systemic disorders, and (rarely) malignancy. The incidence and prevalence of hematospermia in transgender women is unknown. Clinical Course: A 35-year-old transgender woman treated with estradiol valerate and leuprolide presents with persistent hematospermia and two years of intermittent hematuria. She does not report dysuria, urgency, frequency, or gastrointestinal symptoms and is a lifetime nonsmoker. Chlamydia, gonorrhea, and HIV tests are negative. CT scan 4/2021, cytoscopy 5/2021, and MRI prostrate 7/2022 (with and without IV contrast) were unremarkable. Transrectal ultrasound 9/2022 reveals 17cc prostate and posterior cyst with hemorrhagic products. Two ultrasound-guided transperineal biopsy samples obtained from the cystic structure 11/2022 reveal benign prostatic tissue with a small focus of endometrial-type epithelium (positive immunostains for PAX 8 and ER in epithelium and CD10 in stroma). These findings may indicate endometriosis or a Müllerian cyst. Discussion: The prevalence of endometrial tissue in transgender woman has not been described. Risk factors for endometriosis in AMAB* individuals are hypothesized to include prolonged estrogen exposure, cirrhosis, or chronic post-procedural inflammation1. Because transgender women are routinely treated with extended estrogen-containing regimens, it is of interest to determine if the presence of endometrial tissue is more common than previously thought. Guidelines for management of benign endometrial-type epithelium in transgender women are lacking, including whether ectopic endometrial tissue should be excised due to concern for malignant transformation2. Conclusion: Hematospermia in transgender women on GAHT** may indicate occult Müllerian epithelial tissue growth. *AMAB: Assigned Male at Birth **GAHT: Gender-Affirming Hormone Therapy

Artificial Intelligence to Predict the BRAF V595E Mutation in Canine Urinary Bladder Urothelial Carcinomas.

In dogs, the BRAF mutation (V595E) is common in bladder and prostate cancer and represents a specific diagnostic marker. Recent advantages in artificial intelligence (AI) offer new opportunities in the field of tumour marker detection. While AI histology studies have been conducted in humans to detect BRAF mutation in cancer, comparable studies in animals are lacking. In this study, we used commercially available AI histology software to predict BRAF mutation in whole slide images (WSI) of bladder urothelial carcinomas (UC) stained with haematoxylin and eosin (HE), based on a training (n = 81) and a validation set (n = 96). Among 96 WSI, 57 showed identical PCR and AI-based BRAF predictions, resulting in a sensitivity of 58% and a specificity of 63%. The sensitivity increased substantially to 89% when excluding small or poor-quality tissue sections. Test reliability depended on tumour differentiation (p < 0.01), presence of inflammation (p < 0.01), slide quality (p < 0.02) and sample size (p < 0.02). Based on a small subset of cases with available adjacent non-neoplastic urothelium, AI was able to distinguish malignant from benign epithelium. This is the first study to demonstrate the use of AI histology to predict BRAF mutation status in canine UC. Despite certain limitations, the results highlight the potential of AI in predicting molecular alterations in routine tissue sections.

A rare metachronous presentation of periductal stromal sarcoma in a case of recurrent rhabdomyosarcoma – Case report

Periductal stromal sarcoma (PSS) is a an extremely rare low-grade malignant neoplasm arising from breast periductal stroma. It usually occurs in peri and post-menopausal women. Herein, we report a rare case of a 14 year girl, known case of recurrent Rhabdomyosarcoma (RMS) presenting with periductal stromal sarcoma of breast. To the best of our knowledge, this is a first of its kind to be reported in literature. A 14year girl, known case of Recurrent Pleomorphic Rhabdomyosarcoma of retroperitoneum, presented with an abdominal mass and lump in right breast after 10 years. On chemotherapy, abdominal mass regressed and breast lump progressed in size. On further evaluation by histopathological examination and immunohistochemistry, the breast lump turned out to be a periductal stromal sarcoma. Periductal stromal tumors have histological similarities to phyllodes tumors, with the biphasic presence of hypercellular and variably atypical, mitotically active stroma hugging benign epithelium. There are very few case reports on periductal stromal tumors and thus a rare entity. PSS as a metachronous presentation with recurrent RMS is even more rare with the prevalence of multiple soft tissue sarcomas being 0.08%. A clinically suspected metastatic lesion, if accessible for biopsy, warrants a meticulous histopathological examination to ascertain the cell of origin. The therapeutic strategy and prognosis of PSS is unclear, thus a longer follow up is imperative to determine its prognosis and clinical outcome. 2 case reported so far in younger individuals. 1st case of PSS in a Recurrent RMS.

Yes-associated protein-1 overexpression in ocular surface squamous neoplasia; a potential diagnostic marker and therapeutic target.

Yes-associated protein-1 (YAP-1) is a Hippo system transcription factor, which serves as an oncogene in squamous cell carcinoma, and several solid tumors when the Hippo pathway is dysregulated. Yet, the activity of YAP-1 in ocular surface squamous neoplasia (OSSN) has not been determined. Here, we investigate the relationship between YAP-1 overexpression and OSSN. Using a cross-sectional study design, we recruited 227 OSSN patients from the University Teaching Hospitals in Lusaka, Zambia. Immunohistochemistry was used to assess YAP-1 protein overexpression in tumor tissue relative to surrounding benign squamous epithelium. OSSN patient samples (preinvasive, n = 62, 27% and invasive, n = 165, 73%) were studied. One hundred forty-nine invasive tumors contained adjacent preinvasive tissue, bringing the total number of preinvasive lesions examined to 211 (62 + 149). There was adjacent benign squamous epithelium in 50.2% (114/227) of OSSN samples. Nuclear YAP- 1 was significantly overexpressed in preinvasive (Fisher's (F): p <.0001, Monte Carlo (MC): p <.0001) and invasive (F: p <.0001, MC: p <.0001) OSSN in comparison to adjacent benign squamous epithelium when analyzed for basal keratinocyte positive count, staining intensity, expression pattern, and Immunostaining intensity-distribution index. YAP-1 expression did not differ between preinvasive and invasive OSSN (p >.05), keratinizing and non- keratinizing cancer (p >.05), or between T1/T2 and T3/T4 stages in invasive tumors (p >.05). However, grade 2 and 3 tumors had significantly stronger nucleus YAP-1 overexpression intensity than grade 1 tumors (F: p = .0078, MC: p = .0489). By immunohistochemistry, we identified significant overexpression (upregulation of YAP-1 protein expression) in preinvasive and invasive OSSN lesions compared to neighboring benign squamous epithelium. YAP-1 expression was significantly higher in poorly and moderately differentiated invasive squamous cancer than in well-differentiated carcinomas. Overexpression of YAP-1 within the margin of preinvasive and invasive OSSN, but not in the neighboring normal epithelium, indicates that it plays a role in the development and progression of OSSN.

A Neuroenteric Cyst of the Cavernous Sinus: A Case Report.

Background Neuroenteric cysts (NECs) are benign lesions mostly found as intradural extramedullary lesions in the cervicothoracic spinal cord. NECs in the cavernous sinus are very rare. To the best of our knowledge, this is only the second reported case and the first in an adult. Presentation We present a left cavernous sinus NEC in a 75-year-old female with gradually worsening headache and facial pain unresponsive to medical treatment. Imaging revealed a cystic mass lesion in the left cavernous sinus encasing the distal petrosal and cavernous segment of the internal carotid artery. Initial differential diagnoses included more common pathologies located near the cavernous sinus, including cystic schwannoma, craniopharyngioma, and dermoid and epidermoid tumors. The patient underwent a left pterional craniotomy with an extradural transcavernous approach for surgical exploration and possible resection of this mass lesion. Histopathology revealed an NEC lined with benign respiratory-type epithelium. Postoperative imaging revealed gross total tumor resection. The patient remained neurologically intact with complete resolution of facial pain. Conclusion We present a rare pathology that can easily be misinterpreted as other types of lesions. NECs should be kept in mind for differential diagnosis of cavernous sinus cystic lesions. The surgical aim should be maximal safe excision.

Abstract A051: The spatial landscape of clonal somatic copy number alterations in benign and malignant prostate epithelia

Abstract Defining the transition from benign to malignant tissue is fundamental to improve early diagnosis of cancer. We provide an unsupervised approach (SpatialInferCNV) to study spatial genome integrity, in situ, to gain molecular insight into clonal relationships. We employed spatially resolved transcriptomics (Visium, 10x Genomics) to infer spatial copy number variations in &amp;gt;120 000 spatial regions across multiple organs, tissues and tumors, including three whole axial prostates. We used this information to deduce clonal relationships between regions harboring 5-20 cells. We perform an in-depth spatial analysis of prostate cancer that includes an unprecedented interrogation of up to 50,000 tissue domains in a single patient. For these domains we inferred genome-wide information, which facilitated data driven clustering in a tissue wide fashion at high resolution. We observed that genome-wide somatic copy number alterations revealed distinct clonal patterns benign tissue and nearby tumours. In a tissue section from patient 1 (section H2_1), we observed that many CNVs occurred in clone C, most notably in chromosomes 8 and 10 encoding a MYC amplification and a PTEN deletion. This clone constituted a region of exclusively benign acinar cells branching off a duct lined by largely diploid cells in clones A and B. The unobserved ancestor to clone C then gave rise to a further unobserved clone, and then clones E, F and G. Our results suggest a model for how genomic instability arises in histologically benign tissue that may represent early events in prostate cancer evolution. Furthermore the spatial information allowed us to identify small clonal units not evident from morphology and hence would be overlooked by pathologists. We present the first comprehensive, large-scale, atlas of genomic evolution at high spatial resolution in prostate cancer. Our study adds an important new approach to the armamentarium of cancer molecular pathology. We highlight the power of an unsupervised approach to capture the molecular and spatial continuums in a tissue context and challenge the rationale for focal therapy in prostate cancer. Citation Format: Andrew Erickson, Mengxiao He, Emelie Berglund, Maja Marklund, Reza Mirzazadeh, Niklas Schultz, Linda Kvastad, Alma Andersson, Ludvig Bergenstråhle, Joseph Bergenstråhle, Ludvig Larsson, Leire Alonso Galicia, Alia Shamikh, Elisa Basmaci, Teresita Díaz De Ståhl, Timothy Rajakumar, Dimitrios Doultsinos, Kim Thrane, Andrew L. Ji, Paul A. Khavari, Firaz Tarish, Anna Tanoglidi, Jonas Maaskola, Richard Colling, Tuomas Mirtti, Freddie C. Hamdy, Dan J. Woodcock, Thomas Helleday, Ian G. Mills, Alastair D. Lamb, Joakim Lundeberg. The spatial landscape of clonal somatic copy number alterations in benign and malignant prostate epithelia [abstract]. In: Proceedings of the AACR Special Conference: Advances in Prostate Cancer Research; 2023 Mar 15-18; Denver, Colorado. Philadelphia (PA): AACR; Cancer Res 2023;83(11 Suppl):Abstract nr A051.

(098) The Value to Patients of Immunohistochemical Staining of the Vestibule with CD117 and PGP9.5

Abstract Introduction Neuroproliferative vestibulodynia (NPV), associated with severe entrance dyspareunia, is diagnosed by an abnormally high density of nerves and mast cells as established by Bornstein. This cellular pathology cannot be appreciated even on vulvoscopic examination, making diagnosis only clinically suspected after exclusion of all other forms of vestibulodynia. Once NPV is suspected, a recommended treatment is complete vestibulectomy. Surgical specimen are sent to pathology for routine staining with hematoxylin and eosin (H&amp;E) which cannot confirm the suspected diagnosis of NPV. Objective We wished to assess value to the patient of being made aware of pathologic findings in excised vestibular specimen stained by CD117 and PGP9.5. Methods Since 2019, patients suspected of having NPV who underwent complete vestibulectomy had both routine H&amp;E and specially ordered CD117 and PGP9.5 staining of their excised specimen. Patients were asked post-operatively the benefits of this information. Results 56 specimens were studied. Tissue sizes varied from 5-11 cm long x 0.5 – 4 cm wide x 0.1 – 0.7 cm thick. Based on H&amp;E staining, all patients were found to have benign squamous vestibular epithelium with chronic inflammatory infiltrate at the superficial sub-epithelial stroma (Fig 1). The inflammatory infiltrate was composed of mature appearing lymphocytes in 87%, and a mixture of lymphocytes and plasma cells in 13%. Eosinophils were noted in 25% of cases. No ulcers, dysplastic or malignant cells were noted in any specimen. The diagnosis of NPV was confirmed by CD117 and PGP9.5 staining (Figs 2, 3) with excess mast cells, (&amp;gt; 8 cells per high power field x400) noted in all cases. Every patient in this cohort valued the pathologic information regarding the positive CD117 and PGP9.5 staining as final confirmation of their NPV diagnosis. This was particularly meaningful for those patients who had experienced medical gaslighting. Patients consistently used the term “validating”, saying the pathology report provided “tangible evidence” of a “physical problem wrong” when they had been told their “pain didn’t exist”. One woman said, “having that knowledge was priceless. It's one thing to have a belief that I had neuroproliferative vestibulodynia. It's another thing to KNOW. To have that indisputable proof is one of the most gratifying and emotional moments in my healing journey. It shows that there was something wrong. It wasn't all in my head. I didn't need to ‘just relax’.” Conclusions The clinical diagnosis of NPV is based on excluding other forms of vestibulodynia. The pathologic diagnosis of NPV is not based on routine pathology staining but on specialized IHC staining with CD117 and PGP9.5. If a patient is ignored, misdiagnosed, or invalidated by a provider, the patient loses self-confidence and faith in their own abilities. Clinicians need to be aware that not having visible signs when a patient complains of symptoms does not mean the dysfunction does not exist. Providing pathologic evidence of the root cause of entrance dyspareunia plays a significant role in the healing process. Disclosure No

(187) Routine Staining of Excised Vestibular Specimens with Hematoxylin and Eosin and Immunohistochemical Staining with CD117 and PGP9.5: Added Value to Patients

Abstract Introduction Neuroproliferative vestibulodynia (NPV) is associated with increased density of mast cells in the epithelial basement membrane and nerve endings in the sub-epithelial stroma. As cellular pathology cannot be visualized on physical examination, diagnosis is difficult, and often delayed. Patients with entrance dyspareunia are suspected to have NPV only after excluding other forms of vestibulodynia. Surgical specimens from complete vestibulectomy with vaginal advancement flap reconstruction are sent to pathology for routine staining with hematoxylin and eosin (H&amp;E). Since 2019 we have also ordered immunohistochemical staining with CD117 and PGP9. Objective We wished to compare the pathologic findings in excised vestibular specimen examined by routine H&amp;E staining versus by CD117 and PGP9.5, and to assess the significance to the patient of having both pathologic examinations performed. Methods Patients with suspected neuroproliferative vestibulodynia who underwent complete vestibulectomy with vaginal advancement flap reconstruction had both routine H&amp;E staining and CD117/PGP9.5 staining of the excised specimen. Patients were asked post-operatively if and how this information benefitted them. Results Fifty-six patients formed the study group. Based on H&amp;E staining, all patients were diagnosed with benign squamous vestibular epithelium with chronic inflammation. Gross examination showed tissue sizes varying from 5-11 cm long x 0.5 – 4 cm wide x 0.1 – 0.7 cm thick. Microscopic examination showed chronic inflammatory infiltrate at the superficial sub-epithelial stroma (Fig 1). This was composed of mature appearing lymphocytes in 87%, and a mixture of lymphocytes and plasma cells in 13%. Eosinophils were noted in 25% cases. P16 immunohistochemical staining, performed to rule out HPV when appropriate, was negative in all cases. Focal parakeratosis was noted in 7% cases. No ulcers, dysplastic or malignant cells were noted in any specimen. Based on CD117 and PGP9.5 staining, the diagnosis of NPV was established (Figs 2, 3). Positive results consistent with excess mast cells, greater than 8 cells per high power field x400, were noted in 100% of cases. All patients (100%) valued the pathologic information, especially regarding the positive CD117 and PGP9.5 staining as final confirmation of their NPV diagnosis, in particular after experiencing medical gaslighting. They consistently used the term “validating”, providing “tangible evidence” of a “physical problem wrong with me” when they had been told their “pain didn’t exist”. “Having that ‘knowledge’ was priceless. It's one thing to have a belief that I had neuroproliferative vestibulodynia. It's another thing to KNOW. To have that indisputable proof is one of the most gratifying and emotional moments in my healing journey. It shows that there was something wrong. It wasn't all in my head. I didn't need to ‘just relax’.” Conclusions The clinical diagnosis of NPV is based on excluding other forms of vestibulodynia. The pathologic diagnosis of NPV is not based on routine pathology staining but on immunohistochemical staining with CD117 and PGP9.5. If a patient is ignored, misdiagnosed, or invalidated by a provider, the patient loses self-confidence and faith in their own abilities. Providing pathologic evidence of the root cause of entrance dyspareunia plays a significant role in the healing process. Disclosure No

Peptidomic changes in human serous colorectal cancer patients.

Colorectal cancer (CRC) is the third most common cancer worldwide and one of the leading causes of cancer-related death. Peptidomics, considered a novel branch of proteomics, has an increasing range of applications in the screening, diagnosis, prognosis, and even monitoring of cancer. However, there is little information for peptidomics analysis in CRC. In this study, a comparative peptidomic profiling was analyzed in 3 CRC tissue samples and 3 adjacent intestinal epithelial tissue samples by liquid chromatography-tandem mass spectrometry (LC-MS/MS). Among the total 133 nonredundant peptides identified, 59 were significantly differentially expressed in the CRC samples and benign colonic epithelium conditions [fold change (FC) >2, P<0.05]. Totals of 25 up-regulated and 34 down-regulated peptides were detected, respectively. Gene Ontology (GO) analysis and Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis were applied to predict the possible functions of these relevant precursor proteins. To clearly identify the potential interaction network of peptide precursors, the Search Tool for the Retrieval of Interacting Genes/Proteins (STRING) was used to determine protein interactions and a possible central role in CRC. Our results for the first time revealed the differentially expressed peptides between the serous CRC tissue and the adjacent intestinal epithelial tissue samples, and these prominently variable peptides might have an important potential role in occurrence and development of CRC.

Decreased expression of prolyl hydroxylase 1 is associated with poor prognosis in colorectal cancers

BackgroundProlyl hydroxylase 1 (PHD1) is a prognostic marker in several cancers.Aims and scopesThis study was undertaken to elucidate the clinical relevance of PHD1 in colorectal cancer (CRC) prognosis.Materials and methodsWe compared PHD1 expression on a tissue microarray (TMA) containing samples from 1800 CRCs with corresponding clinicopathological tumor variables and patient survival.ResultsWhile PHD1 staining was always high in benign colorectal epithelium, high PHD1 staining was detectable in only 71.8% of CRCs. Low PHD1 staining was associated with advanced tumor stage (p = 0.0101) and shortened overall survival in CRC patients (p = 0.0011). In a multivariable analysis including tumor stage, histological type and PHD1 staining revealed tumor stage and histological type (p < 0.0001 each), but also PHD1 staining (p = 0.0202) to be independent prognostic markers for CRC.ConclusionsIn our cohort, loss of PHD1 expression independently identified a subset of CRC patients with poor overall survival and might, thus, be a promising prognostic marker. PHD1 targeting may even allow for specific therapeutic approaches for these patients.

Inceptor correlates with markers of prostate cancer progression and modulates insulin/IGF1 signaling and cancer cell migration

ObjectiveThe insulin/insulin-like growth factor 1 (IGF1) pathway is emerging as a crucial component of prostate cancer progression. Therefore, we investigated the role of the novel insulin/IGF1 signaling modulator inceptor in prostate cancer. MethodsWe analyzed the expression of inceptor in human samples of benign prostate epithelium and prostate cancer. Further, we performed signaling and functional assays using prostate cancer cell lines. ResultsWe found that inceptor was expressed in human benign and malignant prostate tissue and its expression positively correlated with various genes of interest, including genes involved in androgen signaling. In vitro, total levels of inceptor were increased upon androgen deprivation and correlated with high levels of androgen receptor in the nucleus. Inceptor overexpression was associated with increased cell migration, altered IGF1R trafficking and higher IGF1R activation. ConclusionsOur in vitro results showed that inceptor expression was associated with androgen status, increased migration, and IGF1R signaling. In human samples, inceptor expression was significantly correlated with markers of prostate cancer progression. Taken together, these data provide a basis for investigation of inceptor in the context of prostate cancer.

Abstract P6-04-16: ART: Automated Region segmentation of Tumor on HER2-stained breast cancer tissue

Abstract Background Computational pathology-based methods, eg, Quantitative Continuous Scoring (QCS) [Gustavson, SABCS 2020], are built to provide objective and quantitative methods to assess HER2 expression in breast cancer (BC). For accurate HER2 quantification, it is important to exclude non-invasive epithelium from analysis since HER2 overexpression could be more frequent in ductal carcinoma in situ (DCIS) and pleomorphic lobular carcinoma in situ (PLCIS) than in invasive BC [Lari, J Cancer 2011]. Generally, computational pathology-based approaches require experts to delineate the invasive BC regions of interest for analysis and exclude all benign/non-invasive epithelium. Developing a tool that delineates the invasive BC regions automatically without human intervention to avoid subjectivity of manual annotation by pathologists is ideal. We developed a novel, deep-learning–based system, called DualScaleNet, to perform Automated Region segmentation of Tumor (ART) by automatically identifying the invasive BC regions and excluding benign/non-invasive epithelium on HER2-stained digitized images. Identification and diagnosis of these regions, especially the in situ tumors are a challenge as they can mimic benign and invasive lesions causing wrong HER2 evaluation. Additional stains (eg, p63 for myoepithelial cells or laminin for basement membrane) are often required for diagnosis [Pinder, Mod Pathol 2010] but were not available for this study. Methods DualScaleNet works simultaneously on HER2-stained immunohistochemistry (IHC) image patches at 2 different resolutions. The target branch uses a higher resolution RGB image (0.5 μm/pixel) to learn accurate local details; the context branch uses a lower resolution image (4.0 μm/pixel) to incorporate more context in visual learning. The algorithm generates 4 output image layers representing probabilities of 4 classes: invasive tumor, ductal/lobular carcinoma in situ, benign epithelium, and other tissue. The final segmentation result is generated by assigning each image pixel the class with the largest probability value. The algorithm was trained using ground truth (GT) annotations generated by 5 pathologists using 6157 square field of views (FOVs), 200-500 μm in size. These FOVs were collected from 850 whole slide images (WSI), spanning 9 commercial BC sample cohorts stained with different HER2 assays and scanned by several versions of the Aperio AT2 scanner. The samples included a mixture of biopsies and resections and covered different BC histologies and HER2 staining intensities. To evaluate the reproducibility of tumor area detection by human pathologists, an interpathologist comparison in detection of invasive tumor regions was performed using 225 FOVs annotated by multiple pathologists. Results Analysis generated an average Dice/F1 Score of 81.6% among different pathologists for invasive cancer. On the same sample set (independent of the ART training set), the invasive cancer detection by the ART algorithm was on par with human pathologists, achieving a similar average Dice/F1 score of 80.7%. Conclusions Novel deep learning-based ART algorithm provides accurate segmentation of invasive cancer on HER2-stained IHC images. The performance was verified against the GT annotations provided by multiple pathologists. Since the algorithm is trained using annotations from multiple pathologists, it is not possible to generate higher accuracy with computational pathology than is achievable between independent pathologists. Importantly, the same WSI read by the ART will consistently output the exact same tumor region identification result thus removing the inherent human subjectivity and variability, while improving the turnaround time for analysis. This development serves as the necessary foundation upon which a computational pathology-based diagnostic can be built. Citation Format: Ansh Kapil, Anatoliy Shumilov, Philipp Wortmann, Sihem Khelifa, Jessica Chan, Michel Vandenberghe, Craig Barker, Mark Gustavson, Danielle Carroll, Hadassah Sade, Günter Schmidt. ART: Automated Region segmentation of Tumor on HER2-stained breast cancer tissue [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 P6-04-16.

The clinicopathological challenges of symptomatic and incidental pulmonary hamartomas diagnosis.

Pulmonary hamartomas (PHs) are the most common benign lung tumors. Usually, they are asymptomatic and incidentally discovered during assessment for other diseases or during the autopsy exam. In this context, we have performed a retrospective analysis of surgical resections in a 5-year series of patients diagnosed with PHs in the Clinic of Pulmonary Diseases, Iaşi, Romania, aiming to evaluate their clinicopathological features. A total of 27 patients with PH (40.74% males and 59.26% females) were evaluated. 33.33% of patients were asymptomatic, while the others exhibited variable symptoms, such as chronic cough, dyspnea, chest pain or weight loss. In most cases, PHs presented as solitary nodules, predominantly disposed in the right upper lobe (40.74% of cases), followed by the right lower lobe (33.34%), and left lower lobe (18.51%). The microscopic examination revealed a mixture of mature mesenchymal tissue, such as hyaline cartilage, adipose tissue, fibromyxoid tissue, and smooth muscle bundles, in variable proportions, associated with clefts of entrapped benign epithelium. A dominant adipose tissue component was observed in one case. PH was associated with a history of extrapulmonary cancer diagnosis, in one patient. Although considered benign lung tumors, PHs diagnosis and therapy may be challenging. Having in mind the possibility of recurrence or their occurrence as a part of specific syndromes, PHs should be thoroughly investigated for an appropriate patients' management. Their complex significance and the correlation with other types of lesions, including malignancies, may be further studied, by more extensive studies of surgical and necroptic cases.