Performance of fluorescence in situ hybridization in biliary brushings with equivocal cytology: an institutional experience.

INTRODUCTION: Biliary brushing (BB) cytology has a sensitivity of 15%-65% and specificity approaching 100% for detecting malignancy. Fluorescence in-situ hybridization (FISH) using the UroVysion probe set has been advocated to enhance the detection of malignancies with reported sensitivity of 43%-84%. We sought to evaluate the performance of FISH in BB with equivocal cytology at our institution. MATERIALS AND METHODS: Patients with atypical and suspicious BB with concurrent diagnostic FISH performed at our institution from 2014 to 2021 were identified through a query of our pathology database. FISH (using UroVysion probe set containing centromere enumeration probes to chromosomes 3, 7, and 17) was positive if at least 5 cells demonstrated polysomy. Electronic medical records were reviewed for pathology results and outcomes. Patients were classified malignant if they had positive pathology or documented clinical impression of malignancy and benign if they had negative pathology and/or documented benign clinical course for at least 12 months. RESULTS: We identified 254 equivocal BB (238 atypical/16 suspicious) with concurrent FISH results from 191 patients (105 benign, 86 malignant). 12% (22/191) of patients were FISH positive. Twenty-four percent (21/86) of patients with malignancy had positive FISH but were nonspecific for pancreaticobiliary/ampullary adenocarcinomas. Almost all positive FISH were associated with malignancy (21/22; 95%). There was 1 positive FISH in a patient with primary sclerosing cholangitis who had a benign outcome. CONCLUSIONS: The small number of positive FISH results in BB with equivocal cytology raises the question of the optimal criteria for malignancy. Using only polysomy could result in lower sensitivity.

Endometriosis first presenting in pleural fluid cytology.

Most patients with thoracic endometriosis present with catamenial pneumothorax, a rare condition in which recurrent episodes occur within 72 h before or after the start of menstruation. We report a case of thoracic endometriosis presenting with recurrent bloody pleural effusions without pneumothorax diagnosed on pleural fluid cytology. We describe the cytomorphology and immunoprofile of thoracic endometriosis and discuss the differential diagnoses, including neoplastic processes. We also highlight the importance of communication with clinicians for timeliness of diagnosis and treatment, especially when thoracic endometriosis is not suspected.

Comparison of Diagnostic Rates and Concordance with Subsequent Surgical Resections between Conventional Smear and ThinPrep Preparations versus ThinPrep Only in Thyroid Fine Needle Aspiration (T-FNA) Specimens.

BACKGROUND: Thyroid fine needle aspiration (T-FNA) is a mainstay in management of thyroid nodules. However, the preparation of T-FNA specimens varies across institutions. Prior studies have compared diagnostic rates between different specimen preparations of T-FNA specimens and their associated advantages and disadvantages. However, few have compared the rates of all diagnostic categories of The Bethesda System for Reporting Thyroid Cytopathology (TBSRTC) between liquid-based preparations (LBPs) and a combination of LBP and conventional smear (CS) preparations. Our study compares TBSRTC diagnostic rates between these 2 cohorts and correlates cytologic diagnoses with subsequent thyroid resections to evaluate rates of neoplasia (RON) and malignancy (ROM). METHODS: 584 consecutive thyroid FNA specimens were collected and stratified by preparation type (ThinPrep [TP] vs. CS & TP). Diagnostic rates for each TBSRTC diagnostic category were calculated. The institution's electronic medical records database was searched for histologic diagnoses of previously sampled thyroid nodules to evaluate the RON and ROM. RESULTS: Of 584 thyroid FNA specimens, 73 (12.5%) and 511 (87.5%) were evaluated by TP only and CS & TP, respectively, reflecting the predominance of rapid on-site evaluation (ROSE) with CS for T-FNAs at our institution. Of the TP only and CS & TP cohorts, 29 (39.7%) and 98 (19.2%) had subsequent resections, respectively. The frequency of non-diagnostic cases was lower in the CS & TP cohort (12.7% vs. 26%). While the diagnostic rate of follicular lesion of undetermined significance was similar for both cohorts, SFN categorization was only utilized in the CS & TP cohort (1.5% vs. 0%). Although RON and ROM were similar between cohorts in many of the TBSRTC categories, there was a higher RON associated with non-diagnostic specimens in the TP only cohort when the denominator included all non-diagnostic cases. CONCLUSION: The combination of CS and LBP may potentially decrease the non-diagnostic rate of T-FNA specimens as well as the number of passes required for diagnosis, particularly with ROSE. Evaluation of morphologic features highlighted in conventional smears may facilitate diagnostic categorization in the "suspicious for follicular neoplasm" category.

Quantitative Image Analysis as an Adjunct to Manual Scoring of ER, PgR, and HER2 in Invasive Breast Carcinoma.

OBJECTIVES: Biomarker expression evaluation for estrogen receptor (ER), progesterone receptor (PgR), and human epidermal growth factor receptor 2 (HER2) is an essential prognostic and predictive parameter for breast cancer and critical for guiding hormonal and neoadjuvant therapy. This study compared quantitative image analysis (QIA) with pathologists' scoring for ER, PgR, and HER2. METHODS: A retrospective analysis was undertaken of 1,367 invasive breast carcinomas, including all histopathology subtypes, for which ER, PgR, and HER2 were analyzed by manual scoring and QIA. The resulting scores were compared, and in a subset of HER2 cases (n = 373, 26%), scores were correlated with available fluorescence in situ hybridization (FISH) results. RESULTS: Concordance between QIA and manual scores for ER, PgR, and HER2 was 93%, 96%, and 90%, respectively. Discordant cases had low positive scores (1%-10%) for ER (n = 33), were due to nonrepresentative region selection (eg, ductal carcinoma in situ) or tumor heterogeneity for PgR (n = 43), and were of one-step difference (negative to equivocal, equivocal to positive, or vice versa) for HER2 (n = 90). Among HER2 cases where FISH results were available, only four (1.0%) showed discordant QIA and FISH results. CONCLUSIONS: QIA is a computer-aided diagnostic support tool for pathologists. It significantly improves ER, PgR, and HER2 scoring standardization. QIA demonstrated excellent concordance with pathologists' scores. To avoid pitfalls, pathologist oversight of representative region selection is recommended.

Performance of Afirma genomic sequencing classifier vs gene expression classifier in Bethesda category III thyroid nodules: An institutional experience.

BACKGROUND: Afirma gene expression classifier (GEC) is an adjunct to thyroid fine needle aspiration shown to improve pre-operative risk assessment and reduce unnecessary surgery of indeterminate thyroid nodules. Genomic sequencing classifier (GSC) is a newer version aiming to improve specificity and positive predictive value (PPV) of Afirma testing. There are limited studies comparing GSC vs GEC. This study was undertaken to compare these classifiers in terms of diagnostic performance and effect on clinical management of indeterminate thyroid nodules. METHODS: The study cohort consisted of patients with thyroid nodules that had a recurrent cytologic diagnosis of atypia of undetermined significance/follicular lesion of undetermined significance (AUS/FLUS) and were tested by either GEC or GSC. Patient demographics, nodule size, and clinical follow-up were recorded. Benign call rate (BCR) of Afirma testing, rate of subsequent surgery (RSS), rate of histology-confirmed malignancy (RHM), as well as diagnostic sensitivity, specificity, PPV, negative predicative value (NPV), and accuracy were calculated and compared between GSC and GEC cohorts. RESULTS: Among 264 AUS/FLUS thyroid nodules, 127 and 137 were tested with GEC and GSC, respectively. Compared to GEC, GSC demonstrated increased BCR (77.3% vs 52%), decreased RSS (31.4% vs 51.2%), greater RHM (29% vs 9.8%) associated with a suspicious Afirma result, as well as improved specificity (82.8% vs 54.5%), PPV (29% vs 9.8%), and diagnostic accuracy (83.9% vs 56.7%), while maintaining high sensitivity and NPV. CONCLUSION: Afirma GSC substantially improved BCR, RSS, RHM, and diagnostic performance, enhancing appropriate triage and thereby helped avoid unnecessary surgery in AUS/FLUS thyroid nodules.

An institutional experience: A retrospective analysis of the effect of transitioning from follicular lesion of undetermined significance to atypia of undetermined significance with subclassified atypia on interobserver concordance, rates of neoplasia, and rates of malignancy.

INTRODUCTION: The rate of malignancy (ROM) in thyroid fine needle aspirations (FNA) classified under "atypia of undetermined significance (AUS)/follicular lesion of undetermined significance (FLUS), including Hürthle cell type (HLUS)" category of The Bethesda system for reporting thyroid cytopathology (TBSRTC) in literature is highly variable. The 2018 TBSRTC was updated to note a preferred categorization of AUS cases into subcategories. This study evaluates the impact of AUS subclassification on rates of neoplasia (RON), rates of malignancy (ROM), and cytopathologist (CP) concordance. METHODS: 93 thyroid FNAs previously diagnosed as FLUS or HLUS from January 1, 2013 to December 31, 2014 with subsequent surgical resection were identified. Four CPs reclassified these cases using TBSRTC AUS subcategories of follicular cells with architectural and/or cytologic atypia, predominantly Hürthle cells, and atypical lymphocytes. RON and ROM were calculated for each diagnostic subcategory for each CP. RESULTS: The original RON and ROM for FLUS cases were 31.4% and 15.1% and were 77.8% and 22.2% for HLUS cases. 10.8% of cases showed diagnostic concordance amongst the four CPs. The most frequently utilized subcategory was architectural atypia. RON ranges for architectural atypia, cytologic atypia, architectural and cytologic atypia, and predominantly Hürthle cells were 28.1% to 35.7%, 0% to 33.3%, 35.3% to 66.7%, and 57.1% to 87.5%. The range of ROM was 13.9% to 16.7%, 0% to 33%, 0% to 42.9%, and 0% to 25%, respectively. CONCLUSION: RON for AUS predominantly Hürthle cells subcategory was higher than previously reported, which may indicate use for tailored patient management pathways. AUS subclassification can result in significant interobserver variability. Therefore, institutions may consider consensus/quality control sessions to optimize diagnostic concordance.

Low-grade squamous intraepithelial lesion on Papanicolaou test: follow-up rates and stratification of risk for high-grade squamous intraepithelial lesion.

INTRODUCTION: Low-grade squamous intraepithelial lesion (LSIL) Papanicolaou test is associated with moderate risk of high-grade squamous intraepithelial lesion (HSIL) at colposcopic biopsy. High-risk human papillomavirus (hrHPV) cotesting risk stratifies patients with LSIL Papanicolaou test, with higher rates of HSIL for those hrHPV+. hrHPV genotyping is not considered in current LSIL management algorithms. MATERIALS AND METHODS: We performed a 2-year retrospective review of LSIL Papanicolaou tests in patients 25 to 65 years old to assess rates of follow-up and HSIL at biopsy. Patient age, hrHPV cotest and genotype results, prior screening results, and follow-up testing for 3 years were recorded. RESULTS: A total of 71.5% (376 of 526) of patients had at least 1 follow-up colposcopic biopsy; 18% had HSIL on follow-up, including 20% of hrHPV+ and 12% of hrHPV-. HSIL at biopsy was most common when HPV16/18 was present (32%) and when multiple subtypes were detected (46%) versus when non-16, non-18 hrHPV alone was present (16%) or hrHPV was negative (12%). Of those hrHPV-, 5 of 22 (23%) with a prior screening abnormality had HSIL versus 1 of 27 (4%) for those without prior abnormalities. Follow-up occurred more commonly for hrHPV+ cotests (82%) than hrHPV- cotests (54%). No differences in follow-up rate based on hrHPV genotyping was seen. CONCLUSIONS: The highest HSIL rates were seen when HPV16/18 was present (32%). HSIL rates were similar for those hrHPV- (12%) and non-16, non-18 hrHPV+ (16%). Follow-up was more common for those hrHPV+, but genotype results did not impact follow-up rates. Past screening results may impact risk of HSIL for hrHPV- cases.

Malignant risk of indeterminate pediatric thyroid nodules-An institutional experience.

BACKGROUND: Few studies focus on pediatric thyroid nodules categorized under indeterminate diagnostic categories. The current study was conducted to assess the risk of malignancy of indeterminate pediatric thyroid nodules. METHODS: A search of the institutional electronic pathology database from 01/2011 to 09/2018 was performed to identify pediatric (<21 years old) thyroid nodules that were interpreted as follicular lesion of undetermined significance (FLUS), suspicious for follicular neoplasm (SFN), or suspicious for malignancy (SFM) and subsequently managed with surgery, repeat fine-needle aspiration (FNA), or ≥ 6 months of clinical/imaging monitoring. Results of follow-up (F/U) surgical resections and repeat FNA/Afirma tests, and clinical and radiologic data were collected. RESULTS: We identified 46 cases from 42 patients (11-20 years old, 33 females and 9 males), including 30 FLUS, 10 SFN, and 6 SFM. Twenty-five FLUS, ten SFN, and six SFM cases underwent surgery. The histology revealed carcinomas in 36% of FLUS, 20% of SFN, and 100% of SFM categories; follicular adenomas in 32% of FLUS and 80% of SFN categories; and benign nodules in 32% of FLUS category. All five nonsurgically treated FLUS cases were considered benign based on the findings of repeat FNA/Afirma tests (n = 3, 3-22 months F/U) or clinical/radiologic exams (n = 2, 8-12 months F/U). CONCLUSIONS: Based on a limited study cohort, malignancy was identified in 36%, 20%, and 100% of surgically managed pediatric thyroid nodules categorized as FLUS, SFN, and SFM, respectively; suggesting a markedly higher malignant rate than the implied malignant risk for FLUS and SFM categories in adults.

Radiation-Induced Skin Changes after Postmastectomy Radiation Therapy: A Pilot Study on Indicators for Timing of Delayed Breast Reconstruction.

BACKGROUND: Delayed autologous breast reconstruction is commonly recommended in patients requiring postmastectomy radiation. This study examines gross and histologic changes in the breast skin of patients who have undergone postmastectomy radiation to help determine when radiation-induced skin changes begin to stabilize. METHODS: A prospective pilot study was conducted on eight patients with invasive breast cancer who required mastectomy and radiotherapy. At the time of mastectomy and 2, 4, 6, 8, and 12 months after completion of radiotherapy, a punch biopsy was taken from the radiated mastectomy skin of each patient. Serial standardized photographs were taken before and after radiotherapy to evaluate the degree of hyperpigmentation and graded by three blinded plastic surgeons. Skin biopsies were processed for histologic assessment of inflammation, elastin organization, and vascularity. RESULTS: Grading of patient photographs revealed an increase in hyperpigmentation after radiotherapy compared with baseline with a gradual improvement over time. SMAD3 immunostaining demonstrated a trend toward an increase in inflammation over 12 months. The elastin distribution within samples showed an increase in fiber disorganization, thickening, and clumping, with no improvement throughout the study period. The average number of vessels per high powered field decreased steadily through the duration of the study. CONCLUSION: Histologic changes in dermal inflammation, elastin organization, and vascularity do not appear to correspond with the gradual improvement of hyperpigmentation, resulting from postmastectomy radiation. These histologic changes persist beyond the 12 month observation period and will require clinical correlation to determine the potential impact on postoperative outcomes.

Ethnic disparity in breast cancer survival in southern Thai women.

BACKGROUND: Breast cancer has the highest incidence in women of all cancers and its burden is expected to continue to increase worldwide, especially in middle-income countries such as Thailand. The southern region of Thailand is unique in that it is comprised of 30% Muslims, whereas the rest of Thailand is 95% Buddhist. Breast cancer incidence and survival differ between these religious groups, but the association between clinical subtype of breast cancer and survival has not yet been assessed. METHODS: Here we characterized differences in breast cancer survival with consideration to clinical subtype by religious group (Muslim Thai and Buddhist Thai women). We compared distributions of age, stage and clinical subtype and assessed overall survival by religion. RESULTS: Our findings show that Muslim Thai women with breast cancer are diagnosed at a younger age, at later stages and have shorter overall survival times compared to Buddhist Thai women with breast cancer. We also observe a higher proportion of triple negative tumors characterized in Muslim Thai women. CONCLUSIONS: Our findings confirm previous studies that have shown lower survival rates in Muslim Thai women compared to Buddhist women with breast cancer and offer novel information on subtype distribution. To date, this is the first study assessing clinical subtypes in southern Thailand by religious status. IMPACT: Our findings are critical in providing information on the role of clinical subtype in cancer disparities and provide evidence from the Southeast Asian region for global studies on breast cancer survival.

Implementing noninvasive follicular thyroid neoplasm with papillary-like nuclear features may potentially impact the risk of malignancy for thyroid nodules categorized as AUS/FLUS and FN/SFN.

BACKGROUND: Noninvasive encapsulated follicular variant of papillary thyroid carcinoma (PTC) has recently been reclassified as noninvasive follicular thyroid neoplasm with papillary-like nuclear features (NIFTP). Implementation of the new terminology may alter the implied risk of malignancy (ROM) across the six categories of The Bethesda System for Reporting Thyroid Cytopathology (TBSRTC). METHODS: The study cohort consisted of thyroid fine needle aspiration (FNA) cases which were assessed between January 2011 and June 2016 and led to surgical resections. For each case, patient demographics as well as cytologic and corresponding histologic diagnoses were recorded. The surgical specimens diagnosed as follicular variant of PTC (FVPTC) were re-reviewed to identify cases that met the diagnostic criteria for NIFTP. The ROM with and without exclusion of NIFTP from malignant categorization, as well as the relative change in ROM were calculated for individual categories of TBSRTC. RESULTS: A total of 908 FNA cases with surgical follow-up were retrieved and PTC was identified in 252 (27.8%) surgical specimens. Twenty-nine of 252 (11.5%) were initially classified as FVPTC, of which 17 (6.7%) were reclassified as NIFTP. The cytologic interpretations for the majority of NIFTP cases were atypia of undetermined significance/follicular lesion of undetermined significance (AUS/FLUS, n = 8) or follicular neoplasm/suspicious for neoplasm/(FN/SFN, n = 4). Excluding NIFTP from malignant categorization resulted in a relative decrease in ROM in AUS/FLUS (25.8%) and FN/SFN (22.3%) categories. CONCLUSION: Our institutional data demonstrates that eliminating NIFTP from malignant categorization may result in a reduction of the implied ROM for AUS/FLUS and FN/SFN categories.

Characteristics of a Breast Pathology Consultation Practice.

CONTEXT: - Intradepartmental consultation is a routine practice commonly used for new diagnoses. Expert interinstitutional case review provides insight into particularly challenging cases. OBJECTIVE: - To investigate the practice of breast pathology consultation at a large tertiary care center. DESIGN: - We reviewed breast pathology cases sent for private consultation and internal cases reviewed by multiple pathologists at a tertiary center. Requisitions and reports were evaluated for diagnostic reason for consultation, rate of multiple pathologist review at the tertiary center, use of immunohistochemistry, and, for private consultation cases, type of sender and concordance with the outside diagnosis. RESULTS: - In the 985 private consultation cases, the most frequent reasons for review were borderline atypia (292 of 878; 33.3%), papillary lesion classification (151 of 878; 17.2%), evaluating invasion (123 of 878; 14%), subtyping carcinoma (75 of 878; 8.5%), and spindle cell (67 of 878; 7.6%) and fibroepithelial (65 of 878; 7.4%) lesion classification. Of 4981 consecutive internal cases, 358 (7.2%) were reviewed, most frequently for borderline atypia (90 of 358; 25.1%), subtyping carcinoma (63 of 358; 17.6%), staging/prognostic features (59 of 358; 16.5%), fibroepithelial lesion classification (45 of 358; 12.6%), evaluating invasion (37 of 358; 10.3%), and papillary (20 of 358; 5.6%) and spindle cell (18 of 358; 5.0%) lesion classification. Of all internal cases, those with a final diagnosis of atypia had a significantly higher rate of review (58 of 241; 24.1%) than those with benign (119 of 2933; 4.1%) or carcinoma (182 of 1807; 10.1%) diagnoses. Immunohistochemistry aided in diagnosis of 39.7% (391 of 985) and 21.2% (76 of 359) of consultation and internally reviewed cases, respectively. CONCLUSIONS: - This study confirms areas of breast pathology that represent diagnostic challenge and supports that pathologists are appropriately using expert consultation.

Cytologic and Immunohistochemical Evaluation of Low-Grade Spindle Cell Lesions of the Gastrointestinal Tract.

Spindle cell lesions of the gastrointestinal tract are relatively uncommon compared with the frequency of their epithelial counterparts. Although gastrointestinal stromal tumors and leiomyomas are the most commonly encountered spindle cell lesions in the stomach and esophagus, respectively, there are other less common diagnostic entities that should be considered for accurate diagnoses as well as appropriate patient treatment and clinical follow-up. Given the morphologic overlap of low-grade spindle cell lesions on cytologic preparations, ancillary studies play a key role in differentiating these lesions from one another.

Metastatic ductal carcinoma of the breast to the thyroid gland diagnosed with fine needle aspiration: A case report with emphasis on morphologic and immunophenotypic features.

Metastases to the thyroid are uncommon [<0.2% of thyroid fine needle aspirations (FNA)]. Of metastases to the thyroid, breast carcinoma is relatively common. The diagnosis of metastasis to the thyroid has important therapeutic and prognostic implications. To our knowledge, a morphologic and immunophenotypic comparison of metastatic ductal carcinoma of the breast and primary thyroid carcinomas has not been reported. Here, we report the case of a 37-year-old female with a history of metastatic ductal carcinoma of the breast (modified Bloom-Richardson grade 2; ER+, PgR+, HER2+) diagnosed 6 years prior. She developed hoarseness, prompting a CT scan. Multiple thyroid nodules were found, including a 1.5 cm hypoechoic, solid, irregularly-shaped nodule. On FNA, cells were arranged singly and in crowded groups, varied in size and degree of pleomorphism, and exhibited rare nuclear grooves, inconspicuous nucleoli, and rare intracytoplasmic lumina with no nuclear pseudoinclusions or colloid (Figs. 1A and B). These findings raised the differential of papillary thyroid carcinoma (Fig. 1C), follicular neoplasm (Fig. 1D), medullary carcinoma (Fig. 1E), parathyroid (Fig. 1F), and metastatic breast carcinoma. Immunostaining for GATA-3 (+), ER (+), PAX-8 (-), and TTF-1 (-) was consistent with metastatic breast carcinoma (Fig. 2). We conclude that metastatic breast carcinoma to the thyroid may morphologically mimic primary thyroid carcinoma on FNA; a panel of immunomarkers, such as GATA-3, hormonal marker(s), PAX-8, and TTF-1, may be useful in some cases. GATA-3 immunostaining for metastatic breast carcinoma was helpful in our case and has not been previously reported in a thyroid metastasis sampled by FNA. Diagn. Cytopathol. 2016;44:530-534. © 2016 Wiley Periodicals, Inc.

Breast Cancer and African Ancestry: Lessons Learned at the 10-Year Anniversary of the Ghana-Michigan Research Partnership and International Breast Registry.

Women with African ancestry in western, sub-Saharan Africa and in the United States represent a population subset facing an increased risk of being diagnosed with biologically aggressive phenotypes of breast cancer that are negative for the estrogen receptor, the progesterone receptor, and the HER2/neu marker. These tumors are commonly referred to as triple-negative breast cancer. Disparities in breast cancer incidence and outcome related to racial or ethnic identity motivated the establishment of the International Breast Registry, on the basis of partnerships between the Komfo Anokye Teaching Hospital in Kumasi, Ghana, the University of Michigan Comprehensive Cancer Center in Ann Arbor, Michigan, and the Henry Ford Health System in Detroit, Michigan. This research collaborative has featured educational training programs as well as scientific investigations related to the comparative biology of breast cancer in Ghanaian African, African American, and white/European American patients. Currently, the International Breast Registry has expanded to include African American patients throughout the United States by partnering with the Sisters Network (a national African American breast cancer survivors' organization) and additional sites in Ghana (representing West Africa) as well as Ethiopia (representing East Africa). Its activities are now coordinated through the Henry Ford Health System International Center for the Study of Breast Cancer Subtypes. Herein, we review the history and results of this international program at its 10-year anniversary.

Cytologic Features and Immunocytochemical Profiles of Malignant Effusions with Metastatic Papillary Thyroid Carcinoma: A Case Series from a Single Institution.

OBJECTIVE: Malignant effusions due to papillary thyroid carcinoma (PTC) are rare, but portend a poor prognosis. PTC metastases, although rare, most frequently occur in the lungs and bone. Therefore, differentiating thyroid etiology of malignant effusions from other sites becomes clinically significant in patient management. This study examines morphologic and immunocytochemical findings in 5 cases of malignant effusions with PTC involvement. STUDY DESIGN: The electronic database at the University of Michigan was searched from January 1, 1995 to December 31, 2014 for malignant pleural effusions with PTC involvement. Clinicopathologic data were obtained from electronic medical records. Cytologic slides were reviewed. RESULTS: Five cases of malignant effusions due to PTC were identified. Characteristic cytologic features of PTC, including ovoid nuclei, irregular nuclear contours, and psammomatous calcifications, were seen. However, the predominant cytologic feature observed was moderate amounts of delicate to vacuolated cytoplasm within the tumor cells. A review of immunocytochemistry demonstrated that all 5 cases showed patchy to diffuse TTF-1 positivity and diffuse positivity for Pax-8. Thyroglobulin only showed focal to patchy positivity in 3 of 5 cases. CONCLUSION: Given the morphologic features found in our case series, an immunocytochemical workup for the evaluation of involvement of an effusion by a thyroid primary is crucial for accurate diagnosis and appropriate clinical treatment.

Utility of estrogen receptor, progesterone receptor, and HER-2/neu analysis of multiple foci in multifocal ipsilateral invasive breast carcinoma.

OBJECTIVES: To determine the frequency of estrogen receptor (ER), progesterone receptor (PR), and HER-2/neu (HER2) testing multiple foci of ipsilateral invasive breast carcinoma at our institution and to evaluate resulting change in treatment recommendation. METHODS: We identified 165 consecutive cases of multifocal invasive breast cancer over a 10-year period (2005-2014). Clinicopathologic features and treatment recommendation were assessed by slide and chart review. RESULTS: Seventy (42.4%) of 165 patients had two or more foci tested. In the first 6 years (2005-2010), frequency of testing two or more foci was 31.6% and increased to 70.6% in 2014. Seven (10%) of 70 had a clinically significant difference in ER/PR and/or HER2 status, five (7.1%) with a difference in HER2, one (1.4%) in ER/PR, and one (1.4%) in both ER/PR and HER2. All cases with difference in status had different histology and/or the largest focus was the most positive one. CONCLUSIONS: Our findings support current recommendations to evaluate additional smaller tumor foci in multifocal invasive breast cancer if the focus is of different grade or histology. Additional features, including specific histology, grade, and ER, PR, and HER2 status of the largest focus, should also be considered when selecting cases for which testing of additional foci may be of benefit.

Young investigator challenge: The utility of GATA3 immunohistochemistry in the evaluation of metastatic breast carcinomas in malignant effusions.

BACKGROUND: It is not uncommon to encounter challenges in the immunohistochemical confirmation of metastatic breast cancer given the limited sensitivities of mammaglobin and gross cystic disease fluid protein 15 (GCDFP-15/BRST-2) and the significant proportion of triple-negative breast carcinomas (ie, tumors that are negative for estrogen receptor [ER], and progesterone receptor [PgR], and human epidermal growth factor 2 [HER2]). GATA binding protein 3 (GATA3) has emerged as a potentially useful immunohistochemical adjunct during the evaluation of metastatic breast carcinomas in cytology specimens. The objective of the current study was to examine GATA3 expression in the context of malignant effusions secondary to both mammary and extramammary malignancies. METHODS: In total, 306 malignant effusions (from 62 metastatic breast carcinomas and 244 extramammary malignancies) were examined using GATA3 immunohistochemistry. Effusions with metastatic breast carcinoma were also examined using immunohistochemistry for additional breast markers (ER, PgR, HER2, mammaglobin, and GCDFP-15/BRST-2). RESULTS: GATA3 immunohistochemistry highlighted the tumor cells in 58 of the 62 samples (93.5%) from patients with metastatic breast carcinoma, which was higher than the observed sensitivity of immunohistochemistry for ER (63.8%), PgR (41.4%), HER2 (15.5%), mammaglobin (22.4%), and GCDFP-15/BRST-2 (5.2%). GATA3 expression also was observed in a subset of malignant effusions secondary to extramammary primaries, specifically, in 28 of 244 specimens (11.5%). CONCLUSIONS: GATA3 is a highly sensitive marker for the detection of metastatic breast carcinomas in effusion specimens. However, this marker is not entirely specific for malignancies of breast origin. Thus, GATA3 should be used in conjunction with additional immunohistochemical markers during the cytologic evaluation of malignant effusions.

Metastases to the Pancreas Encountered on Endoscopic Ultrasound-Guided, Fine-Needle Aspiration.

Metastatic lesions in the pancreas are very uncommon and may be difficult to differentiate from the more commonly encountered primary neoplasms derived from the exocrine and endocrine pancreas because of the significant overlap in clinical presentation, imaging, and cytologic features. Metastasis to the pancreas may occur years after treatment of the primary neoplasm and is often not considered on initial evaluation because of the rarity of such events. The possibility of a metastasis to the pancreas should be entertained in patients with any prior history of malignancy because a proper diagnosis is essential in identifying surgical candidates, or avoiding potentially unnecessary surgery and facilitating triage to more appropriate nonoperative therapy. Herein, we describe intrapancreatic metastases secondary to renal cell carcinoma, melanoma, and lung carcinoma, as documented by cytologic examination of endoscopic ultrasound-guided fine-needle aspiration of the pancreatic masses.