Identification of Glandular (Acinar)/Tubule Formation in Invasive Carcinoma of the Breast: A Study to Determine Concordance Using the World Health Organization Definition.

CONTEXT.­: The Nottingham Grading System (NGS) developed by Elston and Ellis is used to grade invasive breast cancer (IBC). Glandular (acinar)/tubule formation is a component of NGS. OBJECTIVE.­: To investigate the ability of pathologists to identify individual structures that should be classified as glandular (acinar)/tubule formation. DESIGN.­: A total of 58 hematoxylin-eosin photographic images of IBC with 1 structure circled were classified as tubules (41 cases) or nontubules (17 cases) by Professor Ellis. Images were sent as a PowerPoint (Microsoft) file to breast pathologists, who were provided with the World Health Organization definition of a tubule and asked to determine if a circled structure represented a tubule. RESULTS.­: Among 35 pathologists, the κ statistic for assessing agreement in evaluating the 58 images was 0.324 (95% CI, 0.314-0.335). The median concordance rate between a participating pathologist and Professor Ellis was 94.1% for evaluating 17 nontubule cases and 53.7% for 41 tubule cases. A total of 41% of the tubule cases were classified correctly by less than 50% of pathologists. Structures classified as tubules by Professor Ellis but often not recognized as tubules by pathologists included glands with complex architecture, mucinous carcinoma, and the "inverted tubule" pattern of micropapillary carcinoma. A total of 80% of participants reported that they did not have clarity on what represented a tubule. CONCLUSIONS.­: We identified structures that should be included as tubules but that were not readily identified by pathologists. Greater concordance for identification of tubules might be obtained by providing more detailed images and descriptions of the types of structures included as tubules.

Cytologic-Histologic Correlation Practices for Nongynecologic Cytology Specimens: A Survey by the College of American Pathologists Cytopathology Committee.

CONTEXT.­: Cytologic-histologic correlation (CHC) is a Clinical Laboratory Improvement Amendments-mandated requirement for gynecologic cytology, but no similar requirement exists for nongynecologic cytology. This study presents the findings from a College of American Pathologists' survey of nongynecologic cytology practice patterns. OBJECTIVE.­: To survey the current CHC practices for nongynecologic cytology. DESIGN.­: Data were analyzed from a survey developed by the committee and distributed to participants in the Nongynecologic Cytopathology Education Program mailing. RESULTS.­: Adoption of CHC for nongynecologic cytology cases is worldwide, with 88.5% of institutions performing CHC on these specimens, a substantial increase from previous years. Performance of CHC varied by institution type, with clinic or regional/local independent laboratories and national/corporate laboratories performing CHC significantly less frequently than hospitals, university hospitals/academic medical centers, and Veterans Administration/Department of Defense hospital institutions. Most CHC was performed concurrently in real time, when the corresponding surgical specimen was reviewed. Selection for real-time concurrent CHC was by the interpreting pathologist, the pathologist diagnosing the surgical biopsy sample or cytopathology case, or both. Sampling was by far the most common reason for discordance. A 2-step difference was the most frequent threshold for discordance between cytology and surgical specimens, but this criterion varied among institutions, with no majority definition. The positive predictive value of a positive cytology finding was calculated rarely in North American institutions but was calculated more frequently in international institutions. CONCLUSIONS.­: CHC practices for nongynecologic cytopathology mirror those found for CHC of gynecologic cytopathology.

Artificial Intelligence Advances in Transplant Pathology.

Transplant pathology plays a critical role in ensuring that transplanted organs function properly and the immune systems of the recipients do not reject them. To improve outcomes for transplant recipients, accurate diagnosis and timely treatment are essential. Recent advances in artificial intelligence (AI)-empowered digital pathology could help monitor allograft rejection and weaning of immunosuppressive drugs. To explore the role of AI in transplant pathology, we conducted a systematic search of electronic databases from January 2010 to April 2023. The PRISMA checklist was used as a guide for screening article titles, abstracts, and full texts, and we selected articles that met our inclusion criteria. Through this search, we identified 68 articles from multiple databases. After careful screening, only 14 articles were included based on title and abstract. Our review focuses on the AI approaches applied to four transplant organs: heart, lungs, liver, and kidneys. Specifically, we found that several deep learning-based AI models have been developed to analyze digital pathology slides of biopsy specimens from transplant organs. The use of AI models could improve clinicians' decision-making capabilities and reduce diagnostic variability. In conclusion, our review highlights the advancements and limitations of AI in transplant pathology. We believe that these AI technologies have the potential to significantly improve transplant outcomes and pave the way for future advancements in this field.

Molecular analysis with pancreaseq® in evaluation and management of pancreatic cysts: A cohort of 28 patients.

Objectives: Herein, we present the PancreaSeq® results of 28 patients and emphasize the usefulness of molecular testing in evaluation of pancreatic cysts. Material and Methods: A total of 10 (35.7%) non-diagnostic, 6 (21.4%) negative, 5 (17.8%) atypical, and 7 (25%) were positive for mucinous cystic neoplasm (MCN) pancreatic cyst aspirates were analyzed with PancreaSeq® at Mayo Clinic, Jacksonville between September 2021 and February 2023. Results: Three non-diagnostic, two negative, three atypical, and two positive for MCN cysts were positive for KRAS and GNAS mutations. They were interpreted as intraductal papillary mucinous neoplasm (IPMN) with low risk for progression to high-grade dysplasia/adenocarcinoma. One negative case was positive for KRAS and GNAS mutation and RNF43 copy number alteration. It was interpreted as IPMN with a low risk of progression. Two non-diagnostic, one negative, and two positive for MCN cysts were positive for KRAS mutation. All were interpreted as IPMN/MCNs with low risk of progression. One positive for MCN case was positive for GNAS mutation and ALK fusion and one positive for MCN case was positive for GNAS mutation, ALK fusion, and RNF43 copy number alteration. Both were interpreted as IPMN and their risk of progression was interpreted as not well understood. One atypical case was positive for KRAS and TP53 mutation and was interpreted as IPMN/ MCNs with a high risk of progression. VHL mutation was present in one non-diagnostic case. It was interpreted as serous cystadenoma and the risk for progression was low. Conclusion: Molecular analysis of pancreatic cysts with PancreaSeq® is useful in accurate diagnosis, especially when cytologic material is non-diagnostic and helps improve patient management.

Evaluating Low HER2 Status in Invasive Breast Carcinoma via HER2 Immunohistochemistry, with HER2 FISH Correlation: A Cohort of 112 Patients.

Introduction: Recent trials demonstrated clinically significant benefits in HER2-nonamplified breast cancer with HER2-low expression using novel anti-HER2 antibody-drug conjugates. Thus, HER2-low breast cancer was proposed as a separate diagnostic entity. Herein, we reclassify HER2-negative cancers according to the new HER2-low category using a modified system and further investigate HER2-very-low expression. Methods: 114 HER2 immunohistochemistry (IHC)-negative invasive breast tumors were identified from the pathology database of Mayo Clinic, Jacksonville, FL, between January 2019 and August 2022. Two blinded breast pathologists (BP) independently rescored HER2 IHC slides at 200x and 400x magnification. Discordant cases between the two BPs were rescored together. The most recent 2018 ASCO/CAP HER2 scoring criteria were used. HER2 (0) was subdivided into HER2 (absent) and HER2 (very low). HER2 FISH testing was performed in all cases. Results: The cohort comprised of 38 (33.3%) HER2 (0) and 76 (66.7%) HER2 (1+) tumors. The first round of rescoring at 200x and 400x magnification resulted in 17 (14.9%) HER2 (absent), 31 (27.2%) HER2 (very low), and 64 (56.2%) HER2 (1+) and 2 (1.8%) HER2 (2+) tumors by BP1 and 20 (17.5%) HER2 (absent), 33 (28.9%) HER2 (very low), and 61 (53.5%) HER2 (1+) tumors by BP2. The combined final rescoring by BP1 and BP2 was as follows: 15 (13.2%) HER2 (absent), 35 (30.7%) HER2 (very low), 63 (55.3%) HER2 (1+), and 1 (0.9%) HER2 (2+) cases. A comparison of the first round of rescoring between two BPs showed substantial agreement with Cohen's kappa value of 0.67. Both comparisons of first rescoring by BP1 and by BP2 to combined final rescoring showed almost perfect agreement with Cohen's kappa value of 0.83.Follow-up FISH studies showed one amplified tumor. Conclusion: Our data support the need for finer granularity, classification, and understanding of HER2-low breast cancers. We also show that reproducibility between trained BP can be obtained, albeit with scoring at high power and low threshold for showing challenging interpretations.

First Report of Management of Sequential Small Cell Transformation and ALK I1171T Mutation as Resistance Mechanisms in a Patient With ALK-EML4 Fused Non-Small Cell Lung Adenocarcinoma With a Novel Combination of Temozolomide and Lorlatinib: A Case Report.

ALK-EML4 fusion-positive lung adenocarcinomas (LUADs) are effectively treated with ALK tyrosine kinase inhibitors, but most patients eventually develop resistance to these drugs owing to ALK-dependent or independent mechanisms. Endothelial to mesenchymal transformation with SCLC development is an ALK-independent mechanism of resistance that has not been previously reported with sequential ALK I1171T mutation while the patient is on treatment for the SCLC. Here, we report the first case of sequential SCLC transformation followed by ALK I1171T mutation in a patient with ALK-EML4 fusion-positive LUAD. After progression on multiple lines of therapy, we describe our experience of managing ALK-mutant LUAD and transformed SCLC with a novel combination of lorlatinib and temozolomide. We also briefly summarize cases of endothelial to mesenchymal transformation ALK-mutant LUAD from the literature.

Two unique cases of metastatic malignant melanoma of the gastrointestinal tract.

INTRODUCTION AND IMPORTANCE: Gastrointestinal tract (GIT) is a common site for malignant melanoma metastasis, with small bowel being the most common. It is usually difficult to diagnose at an early stage because of the anatomical location of the disease. It is also challenging for pathologists to diagnose due to the small amount of biopsy samples. Survival rates of melanoma patients with distant metastasis are very poor. CASE PRESENTATION: This study presents two males, aged 67 and 69 years old, who have metastatic melanoma within the GIT. One was metastasis to the esophagus and another with metastasis to the jejunum presenting as intraluminal masses. Their clinical history and pathologic features of the metastasis are evaluated to give an insight into this disease. CLINICAL DISCUSSION: Gastrointestinal melanoma is hard to detect due to its anatomical location and limited ability to biopsy. Typically, they present at an advanced stage when diagnosed. Approximately 60 % of patients with cutaneous melanoma will have GIT metastasis at the time of autopsy. The small bowel was found to have an affinity for malignant melanoma due to the expression of the CCR9 ligand, CCL25. BRAF mutations are much less observed in GIT mucosal melanomas as compared to cutaneous melanomas. Furthermore, AKAP13-NTRK3 fusion has been reported specifically in the GIT mucosal melanomas. NTRK fusions in general can be observed in metastatic melanomas and have been reported in GIT metastatic melanomas. CONCLUSION: GIT malignant melanomas are difficult to detect due to their anatomical location, with poor prognosis, and have a unique genetic profile.

Metastatic Thyroid Carcinoma to the Kidneys Presenting Initially as Bilateral Renal Masses: A Rare Case Report and Literature Review.

Thyroid cancers exist in multiple forms. Papillary and follicular carcinomas of the thyroid are often referred to as well-differentiated thyroid cancers. Well-differentiated thyroid cancers rarely present as a distant metastatic cancer on initial diagnosis. Papillary thyroid cancer tends to have a good prognosis; however, if distant metastasis of PTC is present, there is usually a poor clinical outcome with a less favorable prognosis. In this study, we report a 90-year-old female who presented with right-sided abdominal discomfort. A renal ultrasound revealed bilateral upper pole renal masses. A percutaneous biopsy was ordered, and the microscopic examination revealed bilateral renal metastasis with a follicular variant of papillary thyroid carcinoma. The patient underwent thyroidectomy and sustained radiation therapy for her bilateral renal metastases. She died 6 years after her initial diagnosis, due to sepsis. This is the second study in literature to report bilateral renal metastasis of follicular variant of papillary thyroid cancer.

A rare case of BK virus non-hemorrhagic cystitis following lung transplant.

BK virus cystitis is known to occur following hematopoietic stem cell transplant (HSCT), but few cases exist in the literature following lung transplant. Because of the rarity of this presentation, patients may have missed diagnoses and prescribed ineffective treatments. We present our case of an atypical presentation of BK virus cystitis appearing as bladder carcinoma in situ in a lung transplant patient.

Fat Necrosis Mimicking Renal Cell Carcinoma Recurrence Following Cryotherapy, Partial Nephrectomy, and Nephrectomy.

OBJECTIVE: To present our experience with three patients surgically treated for suspected recurrent renal cell carcinoma whose final pathology was consistent with tumefactive fat necrosis. METHODS: Three patients underwent definitive therapy for biopsy proven renal cell carcinoma (cryoablation, partial nephrectomy, and nephrectomy) and later demonstrated evidence of recurrent renal cell carcinoma on follow up imaging. All three patients underwent surgical resection of the suspected recurrences with final pathology consistent with tumefactive fat necrosis. RESULTS: The three patients were 60, 74, and 39-years old, respectively. The previous definitive therapies for renal cell carcinoma were percutaneous ablation, RAPN, and nephrectomy. Each patient had previous surgical pathology that confirmed prior renal cell carcinoma. Signs of recurrence on diagnostic imaging occurred 2 years, 23 months, and 8 months post-definitive therapy. CONCLUSION: In patients with a history of renal cell carcinoma, consideration of fat necrosis should be taken into account upon seeing imaging concerning for tumor recurrence. Continued analysis of cases with such a diagnosis will be beneficial in recognizing this possibility to avoid unnecessary surgery or therapy when possible.

PLEKHA7, an Apical Adherens Junction Protein, Suppresses Inflammatory Breast Cancer in the Context of High E-Cadherin and p120-Catenin Expression.

Inflammatory breast cancer is a highly aggressive form of breast cancer that forms clusters of tumor emboli in dermal lymphatics and readily metastasizes. These cancers express high levels of E-cadherin, the major mediator of adherens junctions, which enhances formation of tumor emboli. Previous studies suggest that E-cadherin promotes cancer when the balance between apical and basolateral cadherin complexes is disrupted. Here, we used immunohistochemistry of inflammatory breast cancer patient samples and analysis of cell lines to determine the expression of PLEKHA7, an apical adherens junction protein. We used viral transduction to re-express PLEKHA7 in inflammatory breast cancer cells and examined their aggressiveness in 2D and 3D cultures and in vivo. We determined that PLEKHA7 was deregulated in inflammatory breast cancer, demonstrating improper localization or lost expression in most patient samples and very low expression in cell lines. Re-expressing PLEKHA7 suppressed proliferation, anchorage independent growth, spheroid viability, and tumor growth in vivo. The data indicate that PLEKHA7 is frequently deregulated and acts to suppress inflammatory breast cancer. The data also promote the need for future inquiry into the imbalance between apical and basolateral cadherin complexes as driving forces in inflammatory breast cancer.

Oncotype DX and Prosigna in breast cancer patients: A comparison study.

BACKGROUND: Oncotype Dx® (ODX) is the most used prognostic and predictive assay for ER + breast cancer (BCa) and is categorized into low (< 18), intermediate (18 to 30), or high (≥31) risk of recurrence. Prosigna® is a prognostic signature to estimate distant recurrence-free survival for stage I/II, ER+ cancer in postmenopausal women treated with adjuvant therapy. The goal of the study is to assess the agreement between ODX and Prosigna®. MATERIALS AND METHODS: 100 previously ODX classified peri and postmenopausal, early-stage (I or II) BCa patients were retrieved and Prosigna assay was performed on archived tumor blocks on a NanoString nCounter® DX Analysis System. RESULTS: ODX assay was assigned as follows: 57% low, 39% intermediate, and 4% high. There were 8% two-step disagreements (high to low or vice versa) between ODX and Prosigna®; and 42% one-step disagreement (low to intermediate or vice versa). 78% were classified by Prosigna as luminal A and 22% as luminal B. The majority of luminal A cases (67/78; 85.9%) had low ROR score whereas ODX classified almost two-thirds (50/78~ 64%) as low RS. An insignificant percentage of luminal B cases (1/22 - 4.5%) were classified as high RS by ODX, and a modest percentage were classified as high ROR by Prosigna (15/22 ~68%). According to our follow up results, recurrence was detected in three cases. In all three cases; Prosigna was a better indicator of recurrence. CONCLUSIONS: The agreement between ODX and Prosigna® is low, and this has management implications, especially when chemotherapy is needed.

Utility of p16 and HPV testing in oropharyngeal squamous cell carcinoma: An institutional review.

In the US, 60% to 80% of oropharyngeal squamous cell carcinomas (OPSCCs) are associated with human papillomavirus (HPV). However, until recently, no consensus existed about when and how to test for HPV in patients with head and neck cancers. We aimed to evaluate the use of p16 and HPV testing at our institution because p16 immunohistochemistry is reportedly a reliable surrogate marker for HPV detection in OPSCCs. METHODS: We identified all cases at our institution of primary or metastatic squamous cell carcinoma (SCC) of the head and neck with a concurrent p16 immunostain analysis from January 1, 2013, through August 31, 2018. Patient demographic data, tumor characteristics, p16 result, and any HPV result (in situ hybridization and E6 and E7 RNA test) were captured. RESULTS: We identified 104 patients. Most primary tumors (53/57 [93.0%]) and metastases (40/47 [85.1%]) were positive for p16. Thirty-seven cases (35.6%) had reflex high-risk HPV (HR HPV) testing performed. Of the 35 p16-positive cases, 6 had discrepant HR HPV results (p16+ /HPV- ). We identified 47 p16 immunostains that were performed on lymph nodes with primary tumors of unknown origin. Most were cytology cases (34/47 [72.3%]), and most were p16 positive (40/47 [85.1%]). Neither tumor differentiation nor tumor keratinization was predictive of p16 positivity. Tumors with basaloid differentiation were universally p16 positive. CONCLUSION: p16 immunohistochemistry accurately identifies HPV-positive OPSCC. Cytology specimens have an important role in characterizing SCC of unknown origin. HR HPV testing is not routinely required, and results may be discrepant with p16 findings.

Comparison of endoscopic ultrasound-guided fine-needle biopsy versus fine-needle aspiration for genomic profiling and DNA yield in pancreatic cancer: a randomized crossover trial.

BACKGROUND: National guidelines recommend genomic profiling of tumor tissue to guide precision therapy. We compared the specimen adequacy for genomic profiling and yield of DNA between endoscopic ultrasound (EUS)-guided fine-needle biopsy (FNB) and EUS-guided fine-needle aspiration (FNA). METHODS: In our tandem, randomized controlled trial, consecutive patients undergoing EUS for evaluation of pancreatic masses underwent both conventional EUS-FNA with a 25-gauge needle and paired EUS-FNB (19 or 22-gauge needle), with the order randomized (EUS-FNA first followed by EUS-FNB, or vice versa). A minimum of one pass with each needle was obtained for histology. Second and third passes were performed to collect DNA. Specimens were evaluated by a cytopathologist blinded to the needle type. Specimen adequacy for genomic profiling was calculated based on FoundationOne clinical diagnostic (CDx) adequacy requirements. We compared the adequacy for genomic profiling DNA (quantity) and histology yields with both needles. RESULTS: Analysis included 50 patients (25 men; mean age 68 [standard deviation (SD) 13] years), with a mean lesion size of 38 (SD 17) mm; 37 lesions (74 %) were pancreatic ductal adenocarcinoma (PDAC). The mean DNA concentrations in PDAC by FNB and FNA needles were 5.930 (SD 0.881) µg/mL vs. 3.365 (SD 0.788) µg/mL, respectively (P = 0.01). The median standardized histology score per pass with EUS-FNB was 5 (sufficient for histology) and for EUS-FNA was 2 (enough for cytology). Specimen adequacy for genomic profiling and yield of DNA was significantly higher with FNB than with FNA needles. CONCLUSIONS: In this study, adequacy for genomic profiling, DNA, and histology yield were considerably superior using an EUS-FNB needle compared with an EUS-FNA needle.

Impact of a genomic classifier on indeterminate thyroid nodules: an institutional experience.

INTRODUCTION: Indeterminate thyroid cytology (ITC) occurs in 20% to 25% of cases, and the associated risk of malignancy ranges from 5% to 30%. The genomic classifier ThyroSeq (CBLPath/UPMC, Rye Brook, NY), a targeted next-generation sequencing technology, could classify ITC nodules as malignant and nonmalignant. We sought to characterize our institutional experience with ThyroSeq testing. MATERIALS AND METHODS: We retrospectively identified all patients seen from January 2015 through November 2019 who had ITC nodules analyzed with ThyroSeq. Relevant clinical, pathologic, and resection data were reviewed. RESULTS: Of the 133 cases identified, diagnostic categories included atypia (or follicular lesion) of undetermined significance) (n = 65 [48.9%]), suspicious for follicular neoplasm (SFN) (n = 48 [36.1%]), and suspicious for Hürthle cell neoplasm (n = 20 [15.0%]). About half of the papillary thyroid carcinoma (PTC) cases (n = 9 [56.3%]) and more than one-third of the noninvasive follicular thyroid neoplasm with papillary-like nuclear features (NIFTP) cases (n = 3/8 [37.5%]) were classified as SFN. Most patients (n = 87 [65.4%]) did not undergo resection; of these, 73 (83.9%) were negative for all molecular alterations. Of the 54 cases with molecular alterations, isolated RAS or RAS-like variants were most common (n = 35 [64.8%]); 9 (25.7%) were identified in PTC and 8 (22.9%) in NIFTP. NRAS was the most common alteration (n = 20 [37.0%]), followed by HRAS (n = 6 [11.1%]), which was mostly detected in NIFTP cases (n = 4 of 6 [66.7%]). CONCLUSION: Resection was avoided in 73 patients (54.9%) because of negative ThyroSeq results. ThyroSeq v2 and v3 offered a more accurate categorization of ITC nodules, improved patient management, and reduced unnecessary surgical procedures.

Thoracic endometriosis presenting as a catamenial hemothorax with discordant video-assisted thoracoscopic surgery.

Thoracic endometriosis is uncommon and may be overlooked, resulting in a delay in diagnosis. We describe the case of a 47-year-old woman presenting with acute onset pleuritic pain and hemothorax secondary to this rare entity. The diagnosis of thoracic endometriosis is driven by a compatible clinical history coupled with supportive imaging and immunohistochemical findings. Imaging features lack specificity, however, computed tomography and magnetic resonance imaging play an important role in identifying pleural/diaphragmatic involvement and excluding other more common diseases. Immunohistochemical pleural fluid analysis can confirm the presence of hormone receptor-positive endometrial glands and stroma. We illustrate a few potential diagnostic pitfalls, specifically the inconsistency in diagnostic yield of video-assisted thoracoscopic surgery/thoracentesis and the variable temporal association of patients' symptoms and pathology with menstruation. Prompt identification of thoracic endometriosis is important as it enables early institution of therapy and limits future complications.

HER2 testing across practices-Have we come to a consensus on the ideal method of testing? A systematic literature review.

Human epidermal growth factor (HER2) is an oncogene that codes for HER2 protein. The gene is amplified, and protein is overexpressed in 20% of patients and carries a poor prognosis. HER2-positive tumors tend to be more aggressive and highly proliferative. In 2006, trastuzumab, a monoclonal antibody targeting HER2, was approved for use with chemotherapy as an adjuvant treatment for women with HER2-positive breast cancer. The drug has shown improved survival rates for women with HER2-positive breast cancer. As promised for survival in HER2-positive patients continues with new research, and as novel drug approvals emerge, HER2 assessment plays a significant role in adjuvant and in metastatic setting. HER2 assays approved by the US Food and Drug administration include immunohistochemistry (IHC), fluorescence in situ hybridization (FISH), and bright field dual in situ hybridization (DISH). Accuracy of HER2 testing across laboratories has an impact on treatment as false-negative testing can deprive the patients of trastuzumab therapy. The current review will focus on the variability of HER2 testing across laboratories and the potential impact on treatment.

Durable Complete Response With Immune Checkpoint Inhibitor in Breast Cancer With High Tumor Mutational Burden and APOBEC Signature.

Increasing data support the importance of preexisting host immune response and neoantigen burden for determining response to immune checkpoint inhibitors (ICIs). In lung cancer and melanoma, tumor mutational burden (TMB) has emerged as an independent biomarker for ICI response. However, the significance of TMB in breast cancer, particularly in the context of PD-L1 negativity, remains unclear. This report describes a patient with HER2-negative breast cancer with high TMB and an apolipoprotein B mRNA editing enzyme, catalytic polypeptide-like (APOBEC) trinucleotide signature; her disease was refractory to multiple lines of treatments but achieved durable complete response using ICIs and capecitabine. Additional analysis of the tumor revealed a low amount of stromal tumor-infiltrating lymphocytes (sTILs) and PD-L1 negativity, reflecting a poor preexisting host immune response. In collaboration with Foundation Medicine, comprehensive genomic profiling from 14,867 patients with breast cancer with the FoundationOne test was evaluated. Using the cutoff of ≥10 mutations/megabase (mut/Mb) for high TMB, PD-L1 positivity and TMB-high populations were not significantly overlapping (odds ratio, 1.02; P=.87). Up to 79% of TMB-high tumors with >20 mut/Mb were PD-L1-negative. Our study highlights that despite having low TILs and PD-L1 negativity, some patients may still experience response to ICIs.

Folate receptor alpha expression associates with improved disease-free survival in triple negative breast cancer patients.

Triple negative breast cancer (TNBC) comprises 15-20% of all invasive breast cancer and is associated with a poor prognosis. As therapy options are limited for this subtype, there is a significant need to identify new targeted approaches for TNBC patient management. The expression of the folate receptor alpha (FRα) is significantly increased in patients with TNBC and is therefore a potential biomarker and therapeutic target. We optimized and validated a FRα immunohistochemistry method, specific to TNBC, to measure FRα expression in a centrally confirmed cohort of 384 patients with TNBC in order to determine if expression of the protein is associated with invasive disease-free survival (IDFS) and overall survival (OS). The FRα IHC demonstrated exceptional performance characteristics with low intra- and interassay variability as well as minimal lot-to-lot variation. FRα expression, which varied widely from sample to sample, was detected in 274 (71%) of the TNBC lesions. In a multivariable model adjusted for baseline characteristics, FRα expression was associated with improved IDFS (HR = 0.63, p = 0.01) but not with OS. The results demonstrate the potential of targeting the FRα in the majority of TNBC patients and suggest that variable expression may point to a need to stratify on FRα expression in clinical studies.

Patient Discomfort in Relation to Thyroid Nodule Fine-Needle Aspiration (FNA) Performed with or without Parenteral and/or Topical Anesthetic.

OBJECTIVE: There is much reported variation in the impact of local anesthesia on thyroid fine-needle aspiration (FNA) related discomfort. We compare patients undergoing thyroid FNA with subcutaneous injection or topical anesthetic to no anesthetic. METHODS: We conducted a retrospective review of 585 sequential ultrasound guided thyroid FNA procedures in Mayo Clinic. Group 1 (n = 200), no anesthetic; Group 2 (n = 185), subcutaneous injection anesthetic; and Group 3 (n = 200), topical anesthetic. Patient demographics, number of FNA passes, needle gauge, and cytopathology were recorded plus a discomfort score (0 to 10) before and immediately post procedure in all 3 groups and peak discomfort during the FNA in Groups 1 and 2. RESULTS: There were no differences among the 3 groups in age, sex, FNA sufficiency rate, cytopathology, and FNA passes number. There was no significant difference between Groups 1 and 2 in peak discomfort score during the FNA: 0 (45%, 42.2%), 1 to 2 (19%, 24.9%), 3 to 5 (23.5%, 20.5%), 6 to 8 (9.5%, 10.8%), 9 to 10 (3%, 1.6%), respectively. Discomfort score post procedure: 0 (78.5%, 77.8%, 53.5%), 1 to 2 (13%, 13%, 36.5%), 3 to 5 (7%, 7%, 9%), 6 to 8 (1.5%, 2.2%, 1%), 9 to 10 (0%, 0%, 0%) for groups 1, 2, and 3, respectively. There were no significant differences among the 3 groups for a discomfort score ≥3. CONCLUSION: FNA associated patient discomfort was comparable during and after the procedure regardless of the use of anesthetic or the type utilized. Approximately 90% of patients experienced mild to moderate discomfort during the procedure. And 90% reported no more than a level 2 discomfort post procedure. ABBREVIATIONS: End = endocrinology; FNA = fine-needle aspiration; MCF = Mayo Clinic Florida; MCR = Mayo Clinic Rochester.