GATA3: a multispecific but potentially useful marker in surgical pathology: a systematic analysis of 2500 epithelial and nonepithelial tumors. Am J Surg Pathol. 2014;38:13-22. [PMID: 24145643 DOI: 10.1097/pas.0b013e3182a0218f]

Aberrant expression of GATA3 in metastatic adenocarcinoma of the prostate: an important pitfall

AIMS

The distinction of high-grade prostate cancer (PCa) from poorly differentiated urothelial carcinoma (UC) can be somewhat challenging on clinical and morphological grounds alone, yet it is of great importance for prognostication and choice of treatment. GATA3 is a useful immunohistochemical marker to confirm urothelial origin. However, recent works report strong GATA3 immunoexpression in primary high-grade PCa. The aim of this study was to explore GATA3 expression specifically in metastatic PCa.

METHODS AND RESULTS

The pathology databases of four tertiary institutions were queried for cases of metastatic PCa. Available slides and clinical records were reviewed by experienced genitourinary pathologists. Prostatic markers (PSA, PSAP, NKX3.1) and GATA3 immunohistochemistry were performed. A total of 163 metastatic PCa cases were included. At least one prostate marker was positive in each case of non-regional distant metastasis, confirming prostatic origin. GATA3 strong staining was found in four (2.5%) cases: two liver, one bone and one non-regional lymph-node metastases. All four patients had Grade Group 5 PCa at the initial diagnosis. The metastatic prostatic adenocarcinomas were solid, either with no gland formation (n = 3) or with only focal cribriforming (n = 1).

CONCLUSIONS

To our knowledge, this is the first study exploring GATA3 expression specifically in metastatic PCa. Despite being infrequent, GATA3 positivity in high-grade PCa may lead to misdiagnosis, with clinical implications. We recommend a panel of immunohistochemical markers, both prostatic and urothelial, for ruling out UC, either in primary tumour samples or in the event of metastases of unknown primary, when a genitourinary origin is suspected.

Invasive lobular carcinoma metastasis to pancreas mimicking pancreatic signet ring cell carcinoma: A case report and systematic review of the literature

Metastasis to the gastrointestinal tract is a rare instance in the natural history of breast cancer, usually in association with lobular histology and widespread dissemination of disease. We report the case of a 74-year-old woman with a history of invasive lobular carcinoma presenting with a pancreatic metastasis mimicking a primary pancreatic adenocarcinoma; we also present a systematic review of the relevant literature. The presentation of pancreatic metastasis in the setting of breast cancer is unspecific, and histology is of paramount importance for a correct diagnosis; surgical metastasectomy could be of some benefit in the correct clinical setting.

The Application and Pitfalls of Immunohistochemical Markers in Challenging Diagnosis of Genitourinary Pathology

CONTEXT.—

The morphologic features of different entities in genitourinary pathology overlap, presenting a diagnostic challenge, especially when diagnostic materials are limited. Immunohistochemical markers are valuable when morphologic features alone are insufficient for definitive diagnosis. The World Health Organization classification of urinary and male genital tumors has been updated for 2022. An updated review of immunohistochemical markers for newly classified genitourinary neoplasms and their differential diagnosis is needed.

OBJECTIVE.—

To review immunohistochemical markers used in the diagnosis of genitourinary lesions in the kidney, bladder, prostate, and testis. We particularly emphasized difficult differential diagnosis and pitfalls in immunohistochemistry application and interpretation. New markers and new entities in the 2022 World Health Organization classifications of genitourinary tumors are reviewed. Recommended staining panels for commonly encountered difficult differential diagnoses and potential pitfalls are discussed.

DATA SOURCES.—

Review of current literature and our own experience.

CONCLUSIONS.—

Immunohistochemistry is a valuable tool in the diagnosis of problematic lesions of the genitourinary tract. However, the immunostains must be carefully interpreted in the context of morphologic findings with a thorough knowledge of pitfalls and limitations.

The role of fine-needle aspiration biopsy in the diagnosis of malignant tumors

Cytopathology and histopathology play a key role in the process of diagnosing oncological diseases and premalignant conditions. Fine-needle aspiration (FNA) is one of the techniques used for obtaining biopsy of a wide variety of body tissues, causing patients minimal discomfort. Therefore, it is often considered to be the best strategy for investigating and diagnosing some precancerous or potential malignant lesions. Being successful as a means of confirming the clinical suspicion of metastatic recurrence in the cases of an already known cancer, the interest has further focused on the preliminary diagnosis of various types of benign or malignant tumors. In cases of inoperable tumors, this technique is useful for formulating the final diagnosis. FNA biopsy proved its effectiveness as a highly accurate, cost-effective, and safe technique, with potential high diagnostic yield. Immunohistochemistry, used as an additional tool to classical histopathological examination, remains a very practical and reliable technique that promises good results especially in determining the site of origin within metastatic disease.

The International System for Reporting Serous Fluid Cytopathology-An Updated Review

The International System (TIS) for reporting serous fluid cytopathology was published in December 2020 as a joint project by the International Academy of Cytology and the American Society of Cytopathology. The purpose was to standardize the diagnostic criteria and nomenclature used in reporting serous fluid samples, thereby improving the reproducibility of reports and improving communication between pathologists and clinicians. TIS defines a five-tier system consisting of nondiagnostic, negative for malignancy, atypia of uncertain significance, suspicious for malignancy and malignant categories. This review provides an updated summary of the reporting system, risk of malignancy, potential diagnostic pitfalls, and a practical diagnostic approach to serous fluid specimens.

Gene of the month: GATA3

GATA binding protein 3 (GATA3) is a zinc-finger pioneer transcription factor involved in diverse processes. GATA3 regulates gene expression through binding nucleosomal DNA and facilitating chromatin remodelling. Post-translational modifications modulate its activity. During development, GATA3 plays a key role in cell differentiation. Mutations in GATA3 are linked to breast and bladder cancer. GATA3 expression is a feature of the luminal subtype of bladder cancer and has implications for immune status and therapeutic response. It also has clinical relevance in squamous cell carcinomas and soft tissue sarcomas. This paper reviews the structure and function of GATA3, its role in cancer and its use and pitfalls as an immunohistochemical marker.

Carcinoma of unknown primary (CUP): an update for histopathologists

Carcinoma of unknown primary (CUP) is a heterogeneous group of metastatic cancers in which the site of origin is not identifiable. These carcinomas have a poor outcome due to their late presentation with metastatic disease, difficulty in identifying the origin and delay in treatment. The aim of the pathologist is to broadly classify and subtype the cancer and, where possible, to confirm the likely primary site as this information best predicts patient outcome and guides treatment. In this review, we provide histopathologists with diagnostic practice points which contribute to identifying the primary origin in such cases. We present the current clinical evaluation and management from the point of view of the oncologist. We discuss the role of the pathologist in the diagnostic pathway including the control of pre-analytical conditions, assessment of sample adequacy, diagnosis of cancer including diagnostic pitfalls, and evaluation of prognostic and predictive markers. An integrated diagnostic report is ideal in cases of CUP, with results discussed at a forum such as a molecular tumour board and matched with targeted treatment. This highly specialized evolving area ultimately leads to personalized oncology and potentially improved outcomes for patients.

Comparative expression of TRPS1, GATA3, SOX10, mammaglobin, and GCDFP-15 in effusion specimens with breast carcinoma

BACKGROUND

Traditional immunohistochemistry (IHC) for breast carcinomas has shown low detection rates of metastatic breast carcinoma (MBC) in effusions. Although GATA3 has enhanced diagnostic accuracy in this realm, its limited utility in detecting triple-negative breast carcinoma (TNBC) has been highlighted. TRPS1 has been introduced as a potentially sensitive and specific marker in detecting MBC on histologic samples. We investigate the utility of TRPS1 as a marker for MBC in effusion specimens and compare its performance to SOX10, GATA3, mammaglobin (MG), and GCDFP-15.

METHODS

A database search identified malignant effusions involved by MBC between 2013 and 2021. Cases from unique patients with sufficient cellularity were evaluated for TRPS1, GATA3, SOX10, MG, and GCDFP-15 IHC. The intensity and extent of tumor cells (TC) were scored by two pathologists. Any discrepancies were jointly reviewed for consensus.

RESULTS

GATA3 showed the highest rate of positivity (98.2%), followed by TRPS1 (89.5%), MG (43.9%), GCDFP-15 (21.1%), and SOX10 (3.5%). All GATA3-positive cases showed intermediate to high expression. Comparatively, TRPS1 showed more variability in staining extent and intensity. In 13 (22.8%) cases, TRPS1 showed extensive background staining of inflammatory and mesothelial cells. Of six TNBCs, GATA3, and TRPS1 were positive in six (100%) and four (66.7%) cases, respectively.

CONCLUSIONS

While TRPS1 shows a lower detection rate for MBC than GATA-3, using a combination of these markers can enhance effusion cytology's performance in detecting MBC. However, variability in TRPS1 staining intensity and high background TRPS1 staining of inflammatory and mesothelial cells can increase difficulty in its evaluation.

Nipple Lesions of the Breast: An Update on Morphologic Features, Immunohistochemical Findings and Differential Diagnosis

Because of the unique anatomic structure of the nipple, a few specific breast lesions occur only at this site. Large lactiferous sinuses may be involved by inflammatory conditions such as squamous metaplasia of lactiferous ducts and ductal ectasia or be the site of uncommon superficial epithelial neoplasms such as nipple adenoma or syringomatous tumor of the nipple. Paget disease of the nipple may be secondary to intraepidermal extension of ductal carcinoma in situ in the underlying lactiferous ducts or develop from malignant transformation of Toker cells. Invasive breast cancer may also arise primarily in the nipple. Most of these conditions present as a palpable mass and/or skin changes with or without nipple discharge. Due to the delicate location and often relatively small size of nipple lesions, biopsy specimens are often superficial and fragmented, and the interpretation is challenging. Knowledge of the morphologic and immunophenotypic features of nipple lesions is essential in making the correct diagnosis. Information on the molecular alterations underpinning nipple neoplasms is currently very limited.

HepPar1 and GATA-3 Expression in Neuroendocrine Neoplasms: A Potential Trap for Pathologic Diagnosis

OBJECTIVE

To investigate the expression and clinical significance of HepPar1 and GATA-3 in neuroendocrine neoplasms (NENs).

MATERIALS AND METHODS

The expression of HepPar1 and GATA-3 in 144 cases of NENs was detected using immunohistochemistry, and the relevant literature was reviewed.

RESULTS

HepPar1 was localized in the cytoplasm, and the positive rate of HepPar1 was 6.25% (9/144) in 144 NENs, 9 of which were derived from gastrointestinal and pancreatic NENs, including 4 cases of neuroendocrine tumor, grade 1 (NET G1), 4 cases of NET G2, and 1 case of NET G3. GATA-3 was localized in the nucleus; the positive rate of GATA-3 was 7.62% (11/144), which was derived from 5 cases of gastrointestinal and pancreatic NENs, 2 cases of the lung, 2 cases of the liver, 1 case of the testis, and 1 case of the mediastinum. HepPar1 and GATA-3 were coexpressed in 4 cases: 2 cases of gastric NET G1, 1 case of gastric NET G2, and 1 case of pancreatic NET G3 with liver metastasis.

CONCLUSIONS

HepPar1 and GATA-3 can be expressed in NENs, which are potential traps for the pathologic and differential diagnosis of tumors.

GATA3 Expression in HPV-associated and HPV-independent Vulvar Squamous Cell Carcinomas: Patterns of Expression and Prognostic Significance

Substantial diminution or loss of GATA3 expression is reportedly frequent in human papillomavirus-independent (HPVI), p53-mediated vulvar intraepithelial neoplasia. Herein, we study GATA3 expression in vulvar squamous cell carcinoma (VSCC) and assess its clinicopathologic significance. Eighty-six cases of VSCC diagnosed at a single institution were immunohistochemically assessed for their expression of GATA3, as well as any possible relationships with patient outcomes and other clinicopathologic parameters. Given that GATA3 expression pattern in the normal vulvar epidermis is typically strong basal staining with a uniform upward extension until at least the mid epidermal layers, VSCCs were scored using a previously reported tripattern system: pattern 0 (>75% tumor staining), pattern 1 (25% to 75% staining), and pattern 2 (<25% staining). Severe loss of GATA3 expression (pattern 2) was present in both human papillomavirus-associated (HPVA) and HPVI VSCC but was significantly more common in HPVI cases ( P <0.001). Among 52 HPVA VSCCs, 16 (30.7%), 15 (28.8%), and 21 (40.3%) cases showed patterns 0, 1, 2 staining whereas among 34 HPVI VSCCs, the respective frequencies were 1 (2.9%), 5 (14.7%), and 28 (82.3%). None of the 30 p53 abnormal VSCCs showed pattern 0 staining (0%). Five (16.6%) and 25 (83.3%) showed patterns 1 and 2 staining, respectively. On univariate analysis, the pattern 2 cohort showed a significantly worse overall survival (OS) and disease-free survival (DFS) than the pattern 0 or 1 cohort ( P =0.011 and 0.024, respectively), but this finding was not independent of stage on multivariate analysis ( P =0.34; hazard ratio: 1.82; 95% CI: 0.55-6.06). Subgroup analysis of the p53 wild-type cases showed significantly worse OS for pattern 2 than the pattern 0 or 1 cohorts, independent of stage ( P =0.04; hazard ratio: 6.5; 95% CI: 1.08-39.8). Subgroup analysis of p53 abnormal cases, however, showed no difference in OS and DFS among the 3-tiered GATA3 cohorts. In summary, loss of GATA3 may be seen in both HPVA and HPVI VSCCs but is significantly more common in HPVI SCCs. Loss or substantial diminution of GATA3 expression (pattern 2) is a negative prognostic factor in vulvar SCCs, but only in the p53 wild-type subset, where its negative prognostic significance appears to be independent of stage.

TRPS1, a New Promising Marker for Assessment of Distant Metastatic Breast Cancer

This article reviewed the identification of breast cancer in the distant metastatic setting through traditional immunohistochemical markers, such as mammaglobin and GATA3, compared with the novel immunohistochemical stain, Trichorhinophalangeal syndrome-1 (TRPS1). We review previous studies evaluating TRPS1 staining, which were conducted using cytology specimens, as well as our recently conducted study evaluating this stain using surgical tissue samples, both from primary and distant metastatic invasive breast carcinoma. In summary, although no immunohistochemical stain is 100% specific or sensitive, in the metastatic setting where tissue available for ancillary studies is limited, TRPS1 was a reliable and even a standalone marker for breast origin, particularly in cases of triple-negative breast cancer.

Transcriptional repressor GATA binding 1 (TRPS1) immunoexpression in normal skin tissues and various cutaneous tumors

BACKGROUND

Transcriptional repressor GATA binding 1 (TRPS1) is a transcription factor recently shown to play a role in the development of breast and liver cancer. Here, we evaluate TRPS1 immunoexpression in normal skin tissues and various cutaneous tumors.

METHODS

TRPS1 immunohistochemistry was performed in 109 cases of primary cutaneous tumors and 19 cases of metastatic carcinomas. TRPS1 expression was also evaluated in the normal skin tissues.

RESULTS

The normal epidermis was TRPS1-. In contrast, the eccrine apparatus, epithelial compartment of the hair follicles, hair papilla, sebaceous glands, and anogenital mammary-like glands were TRPS1+. In primary cutaneous tumors, TRPS1 positivity varied in poroma (2/3), nodular hidradenoma (4/5), spiradenoma (4/4), cutaneous mixed tumor (5/5), trichilemmal cyst (7/8), proliferating trichilemmal tumor (1/3), pilomatricoma (9/9), sebaceoma (2/5), extramammary Paget disease (13/13), sebaceous carcinoma (2/2), actinic keratosis (3/10), Bowen disease (7/12), and squamous cell carcinoma (1/5) cases. All cases of seborrheic keratosis, basal cell carcinoma, Merkel cell carcinoma, and malignant melanoma were TRPS1-. All metastatic breast carcinoma cases (8/8) were highly positive for TRPS1, while all but one of the other metastatic tumor cases were TRPS1-.

CONCLUSIONS

TRPS1 immunoexpression was observed in several skin appendages and cutaneous tumors.

Molecular Biomarkers of Bladder Cancer: A Mini-Review

Cancers are quite common, but mostly very serious diseases and therefore belong to the most important areas of scientific research activity. Bladder cancer is one of the most common malignancies, it is a heterogeneous disease with significant diagnostic, therapeutic, and prognostic problems. It represents a disease with a variable course and a different response to therapy. The "conventional" prognostic markers used so far cannot reliably predict the natural course of the disease or estimate the tumor response to the chosen type of treatment. Molecular markers can provide us with the opportunity to diagnose a bladder tumor early, identify patients who are at risk of recurrence, or predict how tumors will respond to therapeutic approaches. As a result, diagnostics are found to help clinicians find the best therapeutic options for patients with bladder cancer. In this study, we focused on a brief description of potential molecular markers in bladder tumors in the context of precise diagnostics. Last but not least, we also focused on a new approach to the treatment of cancer using nanomaterials.

Immunohistochemistry in the Diagnosis and Classification of Breast Tumors

CONTEXT.—

In the clinical practice of breast pathology, immunohistochemistry (IHC) of different markers is widely used for the diagnosis and classification of breast lesions.

OBJECTIVE.—

To provide an overview of currently used and recently identified IHC stains that have been implemented in the field of diagnostic breast pathology.

DATA SOURCES.—

Data were obtained from literature review and clinical experience of the authors as breast pathologists.

CONCLUSIONS.—

In the current review, we summarize the common uses of IHC stains for diagnosing different types of breast lesions, especially invasive and noninvasive breast lesions, and benign and malignant spindle cell lesions. In addition, the cutting-edge knowledge of diagnostic carcinoma markers will lead us to further understand the different types of breast carcinoma and differentiate breast carcinomas from other carcinomas of similar morphology. Knowing the strengths and limitations of these markers is essential to the clinical practice of breast pathology.

Disulfidptosis-associated lncRNAs predict breast cancer subtypes

Disulfidptosis is a newly discovered mode of cell death. However, its relationship with breast cancer subtypes remains unclear. In this study, we aimed to construct a disulfidptosis-associated breast cancer subtype prediction model. We obtained 19 disulfidptosis-related genes from published articles and performed correlation analysis with lncRNAs differentially expressed in breast cancer. We then used the random forest algorithm to select important lncRNAs and establish a breast cancer subtype prediction model. We identified 132 lncRNAs significantly associated with disulfidptosis (FDR < 0.01, |R|> 0.15) and selected the first four important lncRNAs to build a prediction model (training set AUC = 0.992). The model accurately predicted breast cancer subtypes (test set AUC = 0.842). Among the key lncRNAs, LINC02188 had the highest expression in the Basal subtype, while LINC01488 and GATA3-AS1 had the lowest expression in Basal. In the Her2 subtype, LINC00511 had the highest expression level compared to other key lncRNAs. GATA3-AS1 had the highest expression in LumA and LumB subtypes, while LINC00511 had the lowest expression in these subtypes. In the Normal subtype, GATA3-AS1 had the highest expression level compared to other key lncRNAs. Our study also found that key lncRNAs were closely related to RNA methylation modification and angiogenesis (FDR < 0.05, |R|> 0.1), as well as immune infiltrating cells (P.adj < 0.01, |R|> 0.1). Our random forest model based on disulfidptosis-related lncRNAs can accurately predict breast cancer subtypes and provide a new direction for research on clinical therapeutic targets for breast cancer.

Prognostic significance of TP53 and PIK3CA mutations analyzed by next-generation sequencing in breast cancer

Breast cancer is one of the most prevalent malignant tumors affecting women globally. It is a heterogeneous disease characterized by mutations in several genes. Several gene panels have been applied to assess the risk of breast cancer and determine the appropriate treatment. As a powerful tool, Next-generation sequencing (NGS) has been widely utilized in cancer research due to its advantages, including high speed, high throughput, and high accuracy. In this study, we aim to analyze the correlation between somatic mutations in breast cancer, analyzed using NGS, and the prognosis of patients. Between May 2018 and May 2019, a total of 313 patients with breast cancer underwent surgical treatment, which included total mastectomy and breast-conserving surgery. Among these patients, 265 were diagnosed with invasive ductal carcinoma. In this study, we analyzed the NGS results, clinicopathological characteristics, and their correlation with prognosis. Using a gene panel, we examined 143 somatic mutations in solid cancers. Notably, the study population included patients who had received neoadjuvant chemotherapy. The mean age of the patients was 53.1 (±10.28) years, and the median follow-up time was 48 months (range, 8-54). Among the 265 patients, 68 had received prior systemic therapy. Of these, 203 underwent breast-conserving surgery, and 62 underwent a mastectomy. Various somatic mutations were observed in NGS, with the most frequent mutation being PIK3CA mutations, which accounted for 44% of all mutations. TP53 mutations were the second most frequent, and ERBB2 mutations were the third most frequent. TP53 mutations were associated with poor disease-free survival (P = .027), while PIK3CA mutations were associated with better disease-free survival (P = .035) than PIK3CA wild-type. In our study, we identified various somatic mutations in breast cancer. Particularly, we found that TP53 and PIK3CA mutations are potentially associated with the prognosis of breast cancer. These findings suggest that the presence of specific mutations may have implications for predicting the prognosis of breast cancer. Further research and validation are needed to gain a deeper understanding of the role of these mutations and their mechanisms in prognosis prediction.

Diagnostic Pitfalls in Breast Cancer Pathology With an Emphasis on Core Needle Biopsy Specimens

CONTEXT.—

Breast pathology has many mimics and diagnostic pitfalls. Evaluation of malignant breast lesions, particularly in the biopsy setting, can be especially challenging, with diagnostic errors having significant management implications.

OBJECTIVE.—

To discuss the pitfalls encountered when evaluating ductal carcinoma in situ and invasive breast carcinomas, providing histologic clues and guidance for appropriate use and interpretation of immunohistochemistry to aid in the correct diagnosis.

DATA SOURCES.—

Data were obtained from review of pertinent literature of ductal carcinoma in situ and invasive breast carcinomas and from the experience of the authors as practicing breast pathologists.

CONCLUSIONS.—

Awareness of the pitfalls in diagnosing breast cancers is important when creating a differential diagnosis for each breast lesion evaluated. This review will cover some of these scenarios to aid in the diagnostic process.

GATA3 immunohistochemistry as a diagnostic adjunct for differentiated vulvar intraepithelial neoplasia: utility and limitations

Herein, the authors evaluate the diagnostic utility and limitations of GATA3 immunohistochemistry for the distinction of differentiated vulvar intraepithelial neoplasia (dVIN) from its potential mimics. Immunohistochemical studies for GATA3, p53, and p16 were performed on 124 pathologic vulvar tissues, inclusive of dVIN (n = 21), vulvar aberrant maturation (n = 10), high-grade squamous intraepithelial lesion (HSIL) (n = 44), and 49 non-neoplastic vulvar dermatoses of various types. GATA3 expression was scored using a modification of previously proposed criteria: pattern 0 (no significant loss of basal layer staining, >75% staining), pattern 1 (25-75% staining), and pattern 2 (<25% staining). With the exception of lichen sclerosus, 8% of which showed pattern 1 or 2 staining, all other non-neoplastic lesions showed pattern 0 expression. Aberrant GATA3 expression (i.e., patterns 1 or 2) was present in 90% of dVIN cases (2 [9.5%], 3 [14.3%], 16 [76.2%] with patterns 0, 1, and 2 respectively), 90% of vulvar aberrant maturation cases (1 [10%],7 [70%], 2 [20%] with patterns 0, 1, and 2 respectively), and 15.9% of HSIL cases (84.1% pattern 0; 2.3% pattern 1; 13.6% pattern 2). All HSIL cases were p16 positive, including the 7 pattern 1 and 2 cases. All cases of dVIN-like HSIL were pattern 0, and all (n = 2) cases of HSIL-like (basaloid) dVIN were pattern 2 (both of the latter cases displayed complete absence of epidermal staining). Only 1 dVIN case was both pattern 0 and p53-wild-type. We conclude that GATA3 is useful for the distinction of dVIN from non-neoplastic dermatoses and from HSIL, but is best used as part of a panel that includes p53 and p16 to mitigate its limitations.

A comprehensive analysis of GATA3 expression in carcinomas of various origins with emphasis on lung carcinomas

GATA3 is a transcription factor involved in the embryogenesis of multiple human tissues and organs and in maintaining cell differentiation and tissue homeostasis in the adult organism. GATA3 is also involved in carcinogenesis and is regarded as a sensitive marker for urothelial and breast carcinomas, although its expression in carcinomas of non-breast/urothelial origin has been frequently reported. In this study, we sought to examine the extent and intensity of GATA3 expression in various carcinomas, mainly lung, urothelial, breast, and various other primary sites. Patients with breast carcinoma (n=40), carcinoma of the urinary bladder/renal pelvis (n=40), lung carcinoma (n=110), and various other origins (n=45) were included in the study. 165 patients had a primary tumor diagnosis, and 70 cases had a metastatic tumor diagnosis. Our results showed that GATA3 expression was significantly more common in carcinomas of the breast, urinary bladder, and renal pelvis compared to all other origins. All primary and 93% of metastatic urinary bladder carcinomas and 94% of primary and 80% of metastatic breast carcinomas expressed GATA3. Expression was lower in the non-urothelial histology of urinary primaries and in triple-negative breast carcinomas (TNBC). Focal staining, mostly faint, was seen in 5.6% of the primary lung adenocarcinomas and 35% of the primary lung squamous cell carcinomas. More extensive and intense staining was seen in 3.7% of the primary lung adenocarcinomas and 12% of the primary lung squamous cell carcinomas. Expression, mostly focal, was also seen in 30% of the metastatic lung carcinomas. Finally, high expression was seen in 12.5% of the other tumors (one metastatic pancreatic carcinoma, one metastatic salivary gland adenocarcinoma not otherwise specified, one metastatic squamous cell carcinoma of the skin, one primary uterine cervix serous carcinoma, and one squamous cell carcinoma of the head and neck), and focal expression was present in another 22% of them. No ideal cut-off for positivity for GATA3 staining could be identified, as increasing the cut-off in either the extent or the intensity of staining increased specificity but decreased sensitivity. In conclusion, our study shows that although GATA3 staining is very helpful in everyday practice in determining the breast/urothelial origin of carcinomas, there are two caveats to its use: the first is that nonclassical histologies of urothelial carcinomas and TNBC may be negative for the marker, and secondly, carcinomas of various origins may show (although rarely) intense positivity.

Diagnostic and Prognostic Roles of GATA3 Immunohistochemistry in Urothelial Carcinoma

This study aimed to evaluate the diagnostic and prognostic roles of GATA-binding protein 3 (GATA3) immunohistochemistry in urothelial carcinoma (UC) using a meta-analysis. We investigated GATA3 immunohistochemical expression rates and performed a subgroup analysis based on tumor site, study location, and histological subtypes. The overall survival rates of patients with GATA3-positive and -negative UC were compared. The estimated GATA3 expression rate was 0.748 (95% confidence interval [CI]: 0.704-0.787). GATA3 expression rates in the urinary bladder and urinary tract were 0.775 (95% CI: 0.727-0.818) and 0.614 (95% CI: 0.426-0.774), respectively. The GATA3 expression rates of noninvasive and invasive UCs were 0.965 (95% CI: 0.938-0.980) and 0.644 (95% CI: 0.581-0.702), respectively. In invasive UCs, there was a significant difference in GATA3 expression between non-muscular invasion and muscular invasion subgroups (0.937, 95% CI: 0.883-0.967 vs. 0.753, 95% CI: 0.645-0.836). GATA3 expression was the highest in the microcytic subtype among the histologic subtypes (0.952, 95% CI: 0.724-0.993). There was a significant correlation between GATA3 expression and better prognosis (hazard ratio: 0.402, 95% CI: 0.311-0.521). Taken together, GATA3 expression significantly correlated with low-stage and better prognosis in UC. GATA3 expression is highly variable across histological subtypes, and one should be careful while interpreting GATA3 expression.

Metastatic Plasmacytoid Urothelial Carcinoma Masquerading as a Primary Signet Ring Cell Carcinoma of the Duodenum

Plasmacytoid urothelial carcinoma can histologically mimic gastrointestinal signet ring cell carcinoma, a potential diagnostic pitfall resulting in improper clinical management. We present a rare case of a malignant duodenal ulcer due to metastasis from plasmacytoid urothelial carcinoma. Only by histological and retrospective immunohistochemical comparison with the primary bladder tumor was this revealed as a metastasis from a plasmacytoid urothelial carcinoma. This case report highlights the importance of clinical correlation and comparison with any previous pathology specimens, the limitations of immunohistochemical staining, and the utilization of both old and new immunohistochemical tools when differentiating signet ring cell carcinomas of primary sites versus potential metastases.

Breast Metastasis Arising from Ileal Neuroendocrine Tumor: an Unusual Presentation

Neuroendocrine tumors (NETs) up to 80% may have metastatic disease to lymph nodes, liver, and bones upon diagnosis due to their indolent course and benign nature. However, metastasis to the breast from gastropancreatic-neuroendocrine tumors (GEP-NETs) is unusual and rarely reported. Furthermore, such metastases may mimic a primary breast carcinoma clinically and radiologically. This case report illustrates an unusual presentation of metastasis to the right breast in addition to liver, pancreas, and lymph nodal metastases in a patient with ileal NET who was operated upon 5 years back. The metastases were detected by somatostatin receptor-based imaging and post-therapy scan which was confirmed by cytology and immunocytochemistry.

GATA-3 expression and its correlation with prognostic factors and survival in canine mammary tumors

Introduction

The transcription factor GATA-3 plays a significant role in mammary gland development and differentiation. Recent studies on human oncology have demonstrated its association with favorable pathologic factors in breast cancer. Canine mammary tumours, proposed as comparative and translational study models, have epidemiological, clinical, biological, and genetic characteristics similar to those of human breast cancers.

Methods

Here, we evaluated the frequency of GATA-3 expression in mammary tumors of dogs and its relationship with prognostic factors and survival. Tumor samples were obtained from 40 female dogs and grouped according to histological type into benign tumors (n = 10), carcinoma in mixed tumors (CMTs) (n = 20), and aggressive tumors (n = 10). CMTs were further separated according to histological grade, and data on clinical staging and diagnosis, histopathological grading, and survival rate were collected.

Results

GATA-3 and estrogen receptor (ER) expression were higher in benign and well-differentiated carcinomas than in aggressive tumors, which showed greater Ki-67 expression. The expression rate of ER in the studied groups was equivalent to that of GATA-3. We identified a strong positive correlation between GATA-3 and ER expression frequencies and a negative correlation between those of GATA-3 and Ki-67. There were associations between GATA-3 (p < 0.001), Ki-67 (p = 0.003), tumor size (p < 0.001), clinical stage (p = 0.002), lymph node metastasis (p < 0.001), and histological grade (p < 0.001) by univariate survival analysis. The parameters ER (p = 0.015) and GATA-3 (p = 0.005) also influenced survival in a multifactorial manner.

Discussion

Kaplan-Meier analysis of survival curves validated our previous findings that dogs with GATA-3 expression in ≥79.4% of cells had significantly higher survival rates (p < 0.001). The performance analysis showed that the expression of GATA-3 in ≥79.4% of cells effectively predicted survival or death in dogs with mammary tumors. Collectively, these results suggest that GATA-3 can be a relevant marker in the study of mammary tumor progression and has potential as a prognosis marker for predicting outcomes in canine mammary tumors.

Primary Gastric Signet Ring Cell Carcinoma or Metastatic Lobular Carcinoma With Signet Ring Cells: A Diagnostic Challenge

Histologically, cells having vacuolated cytoplasm rich in mucin and pushing the nucleus to the periphery are indicative of signet ring cell carcinoma. This condition often affects the digestive system. On the other hand, it is a very uncommon subtype of invasive lobular breast carcinoma, with a higher probability (more than invasive breast carcinoma of no special type {IBC-NST}) to migrate to the stomach, spleen, urinary tract, and uterus. As with other metastatic carcinomas of breast origin, metastatic signet ring cell carcinoma of the breast is often treated with systemic therapies such as chemotherapy or hormonal therapy. However, surgical resection and eventual perioperative chemotherapy are usually recommended in case of primary gastric ring cell carcinomas that are non-metastatic. As a result, misdiagnosis might result in unneeded gastrectomy and chemotherapy, which would result in considerable mortality and morbidity. We report a case of mammary lobular carcinoma with signet ring cells metastatic to the stomach, a variant rarely described and challenging to distinguish from primary gastric signet ring carcinoma.

Peritoneal Mesothelioma-An Update

A remarkable amount of new information has been generated on peritoneal mesothelioma (PeM), ranging from nomenclature changes, including the removal of "malignant" when referring to this neoplasm and the use of the term "tumor" rather than "mesothelioma" to designate the neoplasm formerly known as "well-differentiated papillary mesothelioma", to the acknowledgment that PeMs can be associated with tumor predisposition syndromes or germline mutations. Although the disease is still more frequently seen in caucasian males, PeM is not uncommon in women. In addition, it can represent a diagnostic challenge when it has an uncommon presentation (ie, paraneoplastic syndrome or incidental finding) or when it has confounding histologic features. Ancillary testing, including immunohistochemical stains, in situ hybridization for CDKN2A or NF2 , and molecular studies, in selected cases, allows its correct diagnosis. The molecular landscape of PeM is still a work in progress; however, some findings, such as ALK gene rearrangements and EWSR1/FUS-ATF1 fusions, are specifically seen in PeM of young patients. The biological behavior of PeM is variable; however, cytoreductive surgery and hyperthermic intraperitoneal chemotherapy have markedly improved the survival of patients affected by this disease.

SDH-B, INSM1, and GATA3 expression in cauda equina neuroendocrine tumors: report on 21 cases from a North indian tertiary care center

Primary neuroendocrine tumors (NETs) of the central nervous system are rare, primarily seen in the cauda equina region, known as cauda equina NETs. This study was carried out to evaluate the morphological and immunohistochemical characteristics of cauda equina NETs. All cases of histologically proven NETs that originated within the spinal cord from 2010 to 2021 were retrieved from the surgical pathology electronic database. For each case, the clinical presentation, site, radiological features, functional status, and preoperative diagnosis were recorded. Immunohistochemical stains for GFAP, synaptophysin, chromogranin A, cytokeratin 8/18, INSM1, Ki-67, GATA3, and SDH-B were performed for every case using an automated immunostainer. GATA3 immunohistochemistry was repeated manually. A retrospective probe of records revealed 21 cases of NETs having a mean age of 44 years and slight male dominance (M:F ratio: 1.2:1). Cauda equina was the most prevalent site of involvement (19, 90.5%). The most typical presentation was lower backache and weakness of bilateral lower limbs. The histopathological features were similar to NETs seen at other sites. Reactivity for at least one neuroendocrine marker was seen in all cases while GFAP was negative. Cytokeratin 8/18 was expressed in the majority (88.9%) of cases. INSM1 and GATA3 expression was seen in 20 (95.2%) and 3 (14.3%) cases, respectively. All cases retained SDH-B cytoplasmic staining. Higher Ki-67 index (≥3%) was associated with a higher risk of recurrence. Cauda equina NETs rarely express GATA3 and are unlikely to be associated with SDH mutations. Recurrent cases may be negative for synaptophysin, chromogranin, and cytokeratin; thus, INSM1 immunohistochemistry is helpful.

Breast mass as the first sign of metastasis from rectal carcinoma: a case report and review of the literature

We present a case report of a 41-year-old woman who developed a left breast mass 18 months after undergoing Dixon rectal cancer surgery. The purpose of this case report is to highlight the possibility of breast metastases in patients with colorectal cancer and emphasize the importance of careful evaluation and follow-up as well as timely and accurate diagnosis and management of the metastatic disease. During the physical examination in 2021, we noted that the lower border of the mass was 9 cm from the anal verge and that it occupied approximately one-third of the intestinal lumen. A pathological biopsy revealed the mass in the patient's intestinal lumen was a rectal adenocarcinoma. The patient underwent Dixon surgery for rectal cancer and received subsequent chemotherapy. The patient had no prior history of breast-related medical conditions or a family history of breast cancer. During the current physical examination, we discovered multiple lymphadenopathies in the patient's left neck, bilateral axillae, and left inguinal region, but none elsewhere. We observed a large erythema of about 15x10 cm on the patient's left breast, with scattered hard nodes of varying sizes. Palpation of the area beyond the upper left breast revealed a mass measuring 3x3 cm. We conducted further examinations of the patient, which revealed the breast mass and lymphadenopathy on imaging. However, we did not find any other imaging that had significant diagnostic value. Based on the patient's conventional pathology and immunohistochemical findings, combined with the patient's past medical history, we strongly suspected that the patient's breast mass was of rectal origin. This was confirmed by the abdominal CT performed afterward. The patient was treated with a chemotherapy regimen consisting of irinotecan 260 mg, fluorouracil 2.25 g, and cetuximab 700 mg IV drip, which resulted in a favorable clinical response. This case illustrates that colorectal cancer can metastasize to unusual sites and underscores the importance of thorough evaluation and follow-up, particularly when symptoms are atypical. It also highlights the importance of timely and accurate diagnosis and management of metastatic disease to improve the patient's prognosis.

Basal Cell Carcinoma of the Prostate Misdiagnosed as High-Grade Urothelial Cancer - A Case Report of a Diagnostic Pitfall

Purpose

Basal cell carcinoma of the prostate is rare. Usually, it is diagnosed in elderly men with nocturia, urgency, lower urinary tract obstruction and normal PSA.

Case Presentation

We report on a case of a 56-years-old patient who presented at the emergency ward with weight loss, nausea and vomiting. The diagnostic evaluation showed acute renal failure due to a bladder tumor. After admission to the urology ward and subsequent contrast-enhanced CT urography and contrast-enhanced chest CT, a non-metastatic bladder tumor that infiltrated the right side of the bladder and seminal vesicles was found. High-grade muscle-invasive urothelial carcinoma was diagnosed from TURBT specimens, followed by radical cystoprostatectomy with pelvic lymphadenectomy and formation of ureterocutaneostomy sec. Bricker. The histopathological examination of the resection specimen surprisingly revealed the presence of prostatic basal cell carcinoma pT4N0M0 and not urothelial cancer. Due to renal failure, the patient required hemodialysis. The recommendation of the multidisciplinary oncological meeting was to follow up with the patient by the surgeon-urologist. On imaging six months after surgery, it was suspicious for recurrence. Patient was considered for adjuvant oncological treatment.

Conclusion

Although rare, basal cell carcinoma of the prostate should be considered in patients with lower urinary tract symptoms, hematuria and normal PSA. Transurethral resection of bladder tumor is indicated in patients presenting with hematuria and bladder tumor. In evaluation of such cases rare histological types should be included in the differential diagnosis.

Lobular Breast Carcinoma Mimicking a Primary Gastric Malignancy

Invasive lobular carcinoma (ILC) is the second most common subclass of breast cancer and adds to the breast malignancy burden in women. Studies focused on metastatic patterns of ILC have reported bone, gynecologic organs, the peritoneum, and the gastrointestinal tract as potential sites of metastasis. Metastatic spread to the stomach has been reported, but generally remains an infrequent finding. Due to vague symptomatology and the visual limitations of endoscopic examination, metastatic lesions can often mimic a primary gastric malignancy. Metastasis in the stomach can be challenging to diagnose and requires a multimodal, thorough endoscopic and immunohistochemical evaluation. It is important to distinguish the primary origin of malignant lesions as treatment can range from systemic chemotherapy to surgical resection based on the diagnosis. We present a case of an underlying ILC metastatic lesion mimicking a primary gastric adenocarcinoma.

Primary renal mucinous adenocarcinoma masquerading as a giant renal cyst: a case report

Mucinous adenocarcinoma of the kidney is rarely reported in the literature. We present a previously unreported mucinous adenocarcinoma arising from the renal parenchyma. A 55-year-old male patient with no complaints showed a large cystic hypodense lesion in the upper left kidney on contrast-enhanced computed tomography (CT) scan. A left renal cyst was initially considered, and a partial nephrectomy (PN) was performed. During the operation, a large amount of jelly-like mucus and bean-curd-like necrotic tissue was found in the focus. The pathological diagnosis was mucinous adenocarcinoma, and further systemic examination revealed no clinical evidence of primary disease elsewhere. Then the patient underwent left radical nephrectomy (RN), and the cystic lesion was found in the renal parenchyma, while neither the collecting system nor the ureters were involved. Postoperative sequential chemotherapy and radiotherapy were administered, and no signs of disease recurrence were observed over 30 months of follow-up. Based on a literature review, we summarize the lesion with rarity and the associated dilemma in preoperative diagnosis and treatment. Given the high degree of malignancy, a careful history analysis accompanied by dynamic observation of imaging and tumor markers is recommended for the diagnosis of the disease. Comprehensive treatment based on surgery may improve its clinical outcomes.

TRPS1 outperforms GATA3 in pleural effusions with metastatic breast carcinoma versus mesothelioma

INTRODUCTION

In evaluating malignant pleural fluid cytology, metastatic adenocarcinomas and mesotheliomas are often differential diagnoses. GATA binding protein 3 (GATA3) has historically been used to confirm metastatic breast carcinomas; however, GATA3 has low specificity if mesothelioma is included in differential diagnoses. Trichorhinophalangeal syndrome type 1 (TRPS1) protein is expressed in all types of breast carcinomas, with reported high specificity and sensitivity. We investigated the performance of TRPS1 immunohistochemistry (IHC) and compared it to GATA3 in pleural fluids diagnosed with metastatic breast carcinoma and mesothelioma.

METHODS

Thirty-six consecutive ThinPrep pleural fluids and 4 pleural fine needle aspirations (FNAs) with diagnoses of metastatic breast carcinoma (21) and mesothelioma (19) were retrieved, and IHC with TRPS1 and GATA3 was performed on all. Immunoreactivity scores for TRPS1 were calculated by multiplying percentage of immunoreactive cells by staining intensity. Immunoreactivity scores were negative if 0 or 1, low positive if 2, intermediate positive if 3 or 4, or high positive if 6 or 9. Nuclear immunoreactivity of ≥10% with at least moderate intensity was judged GATA3 positive.

RESULTS

GATA3 showed immunoreactivity in all metastatic breast carcinomas and 84% of mesotheliomas. TRPS1 was immunoreactive in all breast carcinoma cases (18 with a score of 9 and 3 with a score of 6). TRPS1 showed low positivity in 5% of mesothelioma cases with all other cases being negative.

CONCLUSION

When cytomorphologic differential diagnoses of mesothelioma exist, TRPS1 is a more specific marker than GATA3 for confirmation of metastatic breast carcinoma in pleural fluid cytology.

The Anti-Tumorigenic Role of Cannabinoid Receptor 2 in Non-Melanoma Skin Cancer

Five million non-melanoma skin cancers occur globally each year, and it is one of the most common malignant cancers. The dysregulation of the endocannabinoid system, particularly cannabinoid receptor 2 (CB2), is implicated in skin cancer development, progression, and metastasis. Comparing wildtype (WT) to systemic CB2 knockout (CB2^-/-) mice, we performed a spontaneous cancer study in one-year old mice, and subsequently used the multi-stage chemical carcinogenesis model, wherein cancer is initiated by 7,12-dimethylbenz[a]anthracene (DMBA) and promoted by 12-O-tetradecanoylphorbol-13-acetate (TPA). We found that aging CB2^-/- mice have an increased incidence of spontaneous cancerous and precancerous skin lesions compared to their WT counterparts. In the DMBA/TPA model, CB2^-/- developed more and larger papillomas, had decreased spontaneous regression of papillomas, and displayed an altered systemic immune profile, including upregulated CD4+ T cells and dendritic cells, compared to WT mice. Immune cell infiltration in the tumor microenvironment was generally low for both genotypes, although a trend of higher myeloid-derived suppressor cells was observed in the CB2^-/- mice. CB2 expression in carcinogen-exposed skin was significantly higher compared to naïve skin in WT mice, suggesting a role of CB2 on keratinocytes. Taken together, our data show that endogenous CB2 activation plays an anti-tumorigenic role in non-melanoma skin carcinogenesis, potentially via an immune-mediated response involving the alteration of T cells and myeloid cells coupled with the modulation of keratinocyte activity.

TRPS1 expression in cytokeratin 5 expressing triple negative breast cancers, its value as a marker of breast origin

The lack of oestrogen receptor, progesterone receptor and human epidermal growth factor receptor-2 expression in breast cancer (BC) is the basis for the categorization of the tumour as triple negative breast carcinoma (TNBC). The majority of TNBCs are aggressive tumours with common metastases and decreased expression of markers that could help in identifying the metastatic lesion as of mammary origin. Breast markers, such as gross cystic disease fluid protein-15 (GCDPF-15), GATA binding protein 3 (GATA3), mammaglobin (MGB) and SOX10, are not uniquely specific to BC. Our aim was to evaluate trichorhinophalangeal syndrome type 1 (TRPS1) protein as a breast marker in a series of cytokeratin-5-expressing TNBC, mostly corresponding to basal-like TNBCs, previously characterized for the expression of other breast markers. One hundred seventeen TNBCs in tissue microarrays were immunostained for TRPS1. The cut-off for positivity was ≥ 10%. The reproducibility of this classification was also assessed. TRPS1 positivity was detected in 92/117 (79%) cases, and this exceeded the expression of previously tested markers like SOX10 82 (70%), GATA3 11 (9%), MGB 10 (9%) and GCDFP-15 7 (6%). Of the 25 TRPS1-negative cases, 11 were positive with SOX10, whereas 5 to 6 dual negatives displayed positivity for the other makers. The evaluation showed substantial agreement. Of the five markers compared, TRPS1 seems the most sensitive marker for the mammary origin of CK5-expressing TNBCs. Cases that are negative are most often labelled with SOX10, and the remainder may still demonstrate positivity for any of the 3 other markers. TRPS1 has a place in breast marker panels.

Utility of GATA-3 and associated immunohistochemical markers in the differential diagnosis of poorly differentiated urothelial carcinoma

Aims

The aims are to study the utility of GATA-3 along with panel of immunohistochemical (IHC) markers in the differential diagnosis of primary and metastatic poorly differentiated urothelial carcinoma (UC).

Settings and Design

This is a prospective and retrospective observational study.

Subjects and Methods

Poorly differentiated carcinomas of urinary tract and metastatic sites from January 2016 to December 2017 were subjected to a panel of four IHC markers including GATA-3, p63, Cytokeratin (CK) 7, and CK20. Additional markers such as p16, an enzyme called alpha-methylacyl-CoA racemase, CDX2, and thyroid transcription factor 1 were also done depending on the morphology and site.

Statistical Analysis Used

The sensitivity, specificity, positive predictive value, negative predictive value, and accuracy of GATA-3 in making the diagnosis of UC were calculated.

Results

Forty-five cases were included in the study and after appropriate IHC, the diagnosis was resolved as UC in 24 cases. GATA-3 was positive in 83.33% of UC; all the four markers positive in 33.33% and all negative in 4.17% of UC. However, at least one of the four markers was present in 95.83% of UC, except in sarcomatoid UC. GATA-3 had 100% specificity in differentiating from prostate adenocarcinoma.

Conclusion

GATA-3 is a useful marker in the diagnosis of UC in the primary and metastatic sites with a sensitivity of 83.33%. GATA-3 along with other IHC markers in correlation with clinical and imageological features is necessary for making specific diagnosis of poorly differentiated carcinoma.

Mammaglobin-A Expression Is Highly Specific for Tumors Derived from the Breast, the Female Genital Tract, and the Salivary Gland

Human mammaglobin-A (SCGB2A2) is a secretory protein with an unknown function that is used as a diagnostic marker for breast cancer. However, other tumors can also express mammaglobin-A. To comprehensively study patterns of mammaglobin-A expression, a tissue microarray containing 16,328 samples from 128 different tumor types as well as 608 samples of 76 different normal tissue types was analyzed using immunohistochemistry. Mammaglobin-A positivity was found in only a few normal tissues, including luminal cells of the breast as well as endocervical and endometrial glands. In tumor tissues, 37 of 128 tumor categories showed mamma-globin-A staining, 32 of which were derived from one of four organs: breast (6 tumor categories), endometrium (5 tumor categories), ovary (5 tumor categories), and salivary glands (16 tumor categories). Only five additional tumor types showed occasional weak mammaglobin positivity, including medullary thyroid cancer, teratoma of the testis, squamous cell carcinoma of the skin and pharynx, and prostatic adenocarcinoma. Among 1139 evaluable invasive breast carcinomas of no special type, low mammaglobin-A immunostaining was linked to high BRE grade (p = 0.0011), loss of estrogen and progesterone receptor expression (p < 0.0001 each), and triple-negative status (p < 0.0001) but not to patient survival. In endometrial cancer, mammaglobin-A loss was linked to an advanced tumor stage (p = 0.0198). Our data characterize mammaglobin-A as a highly specific marker for tumors derived from either the breast, female genitals, or salivary gland.

BAP1 and Claudin-4, But Not MTAP, Reliably Distinguish Borderline and Low-grade Serous Ovarian Tumors From Peritoneal Mesothelioma

Peritoneal mesothelioma (PM) and serous neoplasms can be difficult to differentiate, particularly in small biopsies. BRCA1-associated protein 1 (BAP1) is expressed in benign tissues, but over 50% of PMs demonstrate complete loss of nuclear expression. Claudin-4, a tight junction protein, is expressed in most epithelial tumors but not in mesotheliomas. Methylthioadenosine phosphorylase (MTAP) is frequently co-deleted with cyclin-dependent kinase inhibitor 2a in mesotheliomas. These markers have proven useful in separating mesothelioma from its mimics, particularly when tumors are pleural based. In the peritoneum, BAP1 loss has been rarely reported in high-grade serous carcinomas, but overall, these markers have been minimally evaluated in ovarian serous borderline tumors and low-grade serous carcinomas. Thus, we assessed the utility of BAP1, claudin-4, and MTAP in the differential diagnosis of PM and low-grade serous neoplasms. Eighteen PM (16 epithelioid, 1 biphasic, and 1 sarcomatous), 24 low-grade serous carcinomas, and 25 serous borderline tumors were stained for BAP1, claudin-4, and MTAP. Loss of BAP1 nuclear expression was observed in 12 (67%) PM (11 epithelioid, 1 biphasic) but was retained in all serous tumors. Claudin-4 was positive in all serous tumors and negative in all PM. Complete loss of cytoplasmic MTAP was noted in 3 (17%) PMs and 1 (4%) serous borderline tumor, while all low-grade serous carcinomas showed retained expression. BAP1 loss reliably distinguishes PM from serous tumors, although it lacks sensitivity. Claudin-4 is a reliable marker to exclude PM. MTAP loss may occur in both PM and serous tumors, and thus is not useful in distinguishing these entities.

Fine needle aspiration of pancreatic lesions focusing on secondary tumors with emphasis of metastatic breast cancer: A clinicopathological study with follow-up

BACKGROUND

The data on metastatic tumors to the pancreas diagnosed by fine needle aspiration (FNA) biopsy is limited. We report our experience of FNA of primary and secondary pancreatic tumors emphasizing metastatic breast cancer in the pancreas.

METHOD

Total 274 cases of pancreatic FNA in 10 years were retrospectively reviewed. Literature review of metastatic breast cancers to the pancreas was performed.

RESULTS

Out of the 274 cases, 7 (7/274, 2.6%) cases were non-diagnostic, 46 (46/274, 16.8%) cases were negative for malignancy, and 40 (40/274, 14.6%) cases were under the category of atypical cells. There were 133 (133/274, 48.5%) cases diagnosed as positive for malignancy, 20 (20/274, 7.3%) suspicious for malignancy, and 28 (28/274, 10.2%) cases in the category of neoplastic: other. The most common neoplasm diagnosed was ductal adenocarcinoma (114/274, 41.6%; 114/133, 85.7% in positive for malignancy category). Ten cases (10/274, 3.7%) were diagnosed as metastatic neoplasms to the pancreas, including four breast infiltrating ductal carcinomas (IDC), one endocervical adenocarcinoma, one anal/rectal squamous cell carcinoma, one renal cell carcinoma, one hepatocellular carcinoma, one seminoma and one lung adenocarcinoma. We summarized the biomarkers of the four metastatic breast cancers and conducted literature review on biomarkers of metastatic breast cancers to the pancreas.

CONCLUSIONS

Upon analyzing FNAs of primary and secondary tumors in the pancreas, we have found breast carcinoma is the most common secondary pancreatic neoplasm in our patient population. Triple negative breast ductal carcinoma is the most common tumor among the metastasis of breast carcinomas to the pancreas. To the best of our knowledge, this study is the first report with a literature review focusing on biomarkers of metastatic breast cancer to the pancreas.

Low-grade oncocytic tumour (LOT) of the kidney is characterised by GATA3 positivity, FOXI1 negativity and mTOR pathway mutations

Aims: We present a 5-case series of low-grade oncocytic tumour of the kidney to further discuss their clinicopathological characteristics. Methods and results: Five patients were included in this study. There were three females and two males aged 45-66 years, with a median age of 65 years. Four tumours were located in the right kidney, and one was located in the left kidney. Most of the tumour sections were yellow-brown in colour. Tumour sizes ranged from 2.5 to 4.5 cm, with a median size of 3 cm. Microscopically, the tumours were well-circumscribed but lacked a fibrous capsule; the tumours consisted of monomorphous oncocytic cells arranged mainly in solid and nested architectural patterns. The tumour cells had uniformly round to oval nuclei and often had perinuclear halos but lacked significant irregularities. Immunohistochemically, the tumour cells showed a diffuse and strong positivity for CK7 and were negative for CD117. The tumour cells were also positive for GATA3, E-cadherin, Pax-8, Succinate dehydrogenase B (SDHB) and Fumarate hydratase (FH), and negative for vimentin, Carbonic anhydrase 9 (CA9), CD10, P504s, CK20, TFE3, TFEB, HMB45, ALK and Forkhead box protein I1 (FOXI1). Next-generation sequencing identified genetic variations in these tumours, including MTOR gene mutations (4/5) and PIK3CA gene mutation (1/5). All patients were alive without disease progression at a median follow-up of 32 months (range 10-57 months). Conclusion: LOT is an emerging renal entity of indolent behaviour that has morphologic overlap with some renal tumours with eosinophilic cytoplasm, primarily with oncocytoma and eosinophilic variant of chromophobe renal cell carcinoma. Familiarity with the distinctive morphological features, immunophenotype and molecular genetics of LOT helps avoid misdiagnosis.

Fibroepithelial urethral polyp with minor prostatic glands in an older man

We describe a man in his 60s with an incidentally detected urethral polyp located in the middle section of his penile shaft. The patient had been suffering from urinary retention for 9 years due to benign prostatic hyperplasia. He was initiated on clean intermittent catheterisation to drain urine 1 year before the detection of the urethral polyp. Holmium laser nucleation of the prostate was performed, and an anterior urethral polyp (5 mm in diameter) was resected. Pathology indicated that the urethral polyp was a fibroepithelial polyp with prostate-specific antigen-immunoreactive heterotopic prostatic glands. There were no problems with urination 6 months after surgery. Fibroepithelial urethral polyps are usually congenital and are rarely described in adults. The clinicopathological features of this polyp, with its uniquely associated minor prostatic glands, are presented.

SOX17: A Highly Sensitive and Specific Immunomarker for Ovarian and Endometrial Carcinomas

PAX8 is the most commonly used immunomarker to link a carcinoma to the gynecologic tract; however, it lacks specificity. Through mining The Cancer Genome Atlas mRNA expression profile data, we identified SOX17 as a potential specific marker at the mRNA level for gynecologic tumors. To evaluate the utility of this marker in the identification of the gynecologic origin of a given carcinoma, we performed immunochemical staining in a large cohort of ovarian and endometrial cancer cases (n = 416), together with a large cohort of solid tumors from other organs (n = 1544) in tissue microarrays. Similar to PAX8, SOX17 was highly expressed in different subtypes of ovarian carcinoma (97.5% for SOX17 vs 97% for PAX8 in serous carcinoma, 90% vs 90% in endometrioid carcinoma, and 100% vs 100% in clear cell carcinoma), except for mucinous carcinoma (0% vs 27%), and was also highly expressed in different subtypes of endometrial carcinoma (88% vs 84% in endometrioid carcinoma, 100% vs 100% in serous and clear cell carcinoma). SOX17 was not expressed in thyroid and renal cell carcinomas, whereas PAX8 expression was high (86% and 85%, respectively). In addition, SOX17 was expressed at low levels in cervical adenocarcinoma (20%) and had no expression in cervical squamous carcinoma, mesothelioma, and carcinomas from the breast, lung, pancreas, colon, stomach, liver, bladder, and salivary gland. Our data indicate that SOX17 is not only a sensitive but also a specific marker for the origin of ovarian and endometrial carcinomas.

[Immunohistology in breast diagnostics : Strategies for efficient diagnostics]

Immunohistological examinations are useful for the histopathological diagnosis of breast carcinoma in various clinical situations. This review article aims to summarize the different immunohistological options. A distinction is made between diagnostic, prognostic, and predictive markers. Especially when a therapeutic decision results from the immunohistological expression pattern, a quantitative, quality-controlled, and validated diagnostic approach is essential.This is relevant, for example, for the classical markers ER, PR, and HER2, but also for Ki-67 and additional markers such as PD-L1. This article provides a practice-oriented summary of the most important immunohistochemical markers in routine breast cancer diagnosis and for the distinction of malignant findings from benign alterations or precursor lesions.

Cauda equina neuroendocrine tumors show biological features distinct from other paragangliomas and visceral neuroendocrine tumors

Cauda equina neuroendocrine tumors (CENETs) are neoplasms of uncertain histogenesis with overlapping features between those of paragangliomas (PGs) and visceral neuroendocrine tumors (NETs). We have explored their biological relationship to both subsets of neuroendocrine neoplasms. The clinical and radiological features of a cohort of 23 CENETs were analyzed. A total of 21 cases were included in tissue microarrays, along with a control group of 38 PGs and 83 NETs. An extensive panel of antibodies was used to assess epithelial phenotype (cytokeratins, E-cadherin, EpCAM, Claudin-4, EMA, CD138), neuronal and neuroendocrine features (synaptophysin, chromogranin A, INSM1, neurofilaments, NeuN, internexin-α, calretinin), chromaffin differentiation (GATA3, Phox2b, tyrosine hydroxylase), and possible histogenesis (Sox2, T-brachyury, Oct3/4, Sox10). The cohort included 5 women (22%) and 18 men (78%). The average age at the time of surgery was 48.3 years (range from 21 to 80 years). The average diameter of the tumors was 39.27 mm, and invasion of surrounding structures was observed in 6/21 (29%) tumors. Follow-up was available in 16 patients (median 46.5 months). One tumor recurred after 19 months. No metastatic behavior and no endocrine activity were observed. Compared to control groups, CENETs lacked expression of epithelial adhesion molecules (EpCAM, CD138, E-cadherin, Claudin-4), and at the same time, they lacked features of chromaffin differentiation (GATA3, Phox2b, tyrosine hydroxylase). We observed no loss of SDHB. Cytokeratin expression was present in all CENETs. All the CENETs showed variable cytoplasmic expression of T-brachyury and limited nuclear expression of Sox2. These findings support the unique nature of the neoplasm with respect to NETs and PGs.

GATA3 expression in primary lung carcinomas: correlation with histopathologic features and TTF-1, napsin A, and p40 expression

This study assessed the expression of GATA3 in primary lung carcinomas and correlated it with tumor histology and immunostains routinely utilized in the work up of primary lung cancers. Tissue microarrays (TMAs) were constructed from a cohort of 184 non-small cell carcinomas, stained with GATA3, p40, TTF-1, and napsin A, and analyzed semi-quantitatively. All TMA cases with GATA3 expression were further analyzed using corresponding whole slide sections. Positive GATA3 staining was present in 16 cases (9%), including 7 squamous cell carcinomas (SqCCs) (4%), 4 adenocarcinomas (AdCs) (2%), 2 adenosquamous carcinomas (AdSqCs) (1%), 2 large cell carcinomas (LCCs) (1%), and 1 sarcomatoid carcinoma (SC) (<1%). Among tumor histotypes, SqCC was more likely to stain with GATA3 (7/49, 14%), while AdC was less likely (4/111, 4%) (p = 0.04). In GATA3-positive cases, high-level expression was observed in 9 cases (56%), including 5 p40-positive SqCCs (3 were nonkeratinizing), 1 p40-positive AdSqC (negative for TTF-1 and napsin A), and 1 AdC (solid), 1 LCC, and 1 SC, each negative for p40, TTF-1, and napsin A). Low-level GATA3 expression was found in 3 AdCs (1 was lepidic and 2 were acinar predominant), 2 SqCCs (keratinizing), 1 AdSqC, and 1 LCC. These findings indicate that GATA3 expression occurs in a minor but significant proportion of primary non-small cell lung carcinomas, most often involves SqCC, and tends to show increasing levels of expression in more poorly differentiated subtypes. Caution should be exercised when interpreting GATA3 expression, and a panel of immunostains should be utilized when assigning tumor origin.

Phox2B is a sensitive and reliable marker of paraganglioma-Phox2B immunohistochemistry in diagnosis of neuroendocrine neoplasms

Phox2B is a transcription factor responsible for chromaffin cell phenotype. Although it is used routinely for diagnosis of neuroblastoma, previous reports concerning its utility in the diagnosis of neuroendocrine neoplasms have been conflicting. We assessed Phox2b immunoreactivity in different neuroendocrine neoplasms. Tissue microarrays or whole sections of 36 paragangliomas (PGs), 91 well-differentiated neuroendocrine tumours of different organs (WDNETs), 31 neuroendocrine carcinomas (NECs), and 6 olfactory neuroblastomas (ONBs) were stained with Phox2B antibody (EP312) and GATA3. The percentage of positive cells and intensity was analysed using H-score. Phox2B immunoreactivity was seen in 97.2% (35/36) PGs, 11% (10/91) WDNETs, 9.7% (3/31) NECs, and 16.7% (1/6) ONBs. PGs were significantly more often positive (p < 0.001, χ²) than other neuroendocrine tumours, showing highest H-score (mean 144.9, SD ± 75.1) and percentage of positive cells (median 81.3%, IQR 62.5-92.5%). Compared to Phox2B-positive WDNETs, PGs showed significantly higher H-score (median 145 vs 7.5, p < 0.001) and percentage of positive cells (median 82.5% vs 4.5%, p < 0.001). Phox2B positivity was 97.2% sensitive and 89% specific for the diagnosis of PG. GATA3 was 100% sensitive and 88% specific for the diagnosis of PG. When combined, any Phox2B/GATA3 coexpression was 97.1% sensitive and 99.1% specific for the diagnosis of paraganglioma. Widespread Phox2B immunoreactivity is a highly characteristic feature of PGs and it can be used as an additional marker in differential diagnosis of neuroendocrine tumours.

GATA3 Expression in Human Tumors: A Tissue Microarray Study on 16,557 Tumors

INTRODUCTION

GATA3 is a transcription factor involved in epithelial cell differentiation. GATA3 immunostaining is used as a diagnostic marker for breast and urothelial cancer but can also occur in other neoplasms.

METHODS

To evaluate GATA3 in normal and tumor tissues, a tissue microarray containing 16,557 samples from 131 different tumor types and subtypes and 608 samples of 76 different normal tissue types was analyzed by immunohistochemistry.

RESULTS

GATA3 positivity was found in 69 different tumor types including 23 types (18%) with at least one strongly positive tumor. Highest positivity rates occurred in noninvasive papillary urothelial carcinoma (92-99%), lobular carcinoma (98%), carcinoma of no special type of the breast (92%), basal cell carcinoma of the skin (97%), invasive urothelial carcinoma (73%), T-cell lymphoma (23%), adenocarcinoma of the salivary gland (16%), squamous cell carcinoma of the skin (16%), and colorectal neuroendocrine carcinoma (12%). In breast cancer, low GATA3 staining was linked to high pT stage (p = 0.03), high BRE grade (p < 0.0001), HER2 overexpression (p = 0.0085), estrogen and progesterone receptor negativity (p < 0.0001 each), and reduced survival (p = 0.03).

CONCLUSION

Our data demonstrate that GATA3 positivity can occur in various tumor entities. Low levels of GATA3 reflect cancer progression and poor patient prognosis in breast cancer.

Marker assessments in ER-positive breast cancers: old markers, new applications?

Evaluation of oestrogen receptor (ER) expression by immunostaining is essential in the pathological assessment of breast cancer. Its expression is intercorrelated with clinicopathological features, molecular typing, and treatment selection. The development of novel therapeutic agents related to ER status, the recent ASCO introduction of an ER-low positive category of breast cancers, and the ever-increasing plethora of diagnostic and theragnostic markers call for a timely update. In this article we aim to review the clinicopathological features of ER-positive breast cancers, with an emphasis on ER-low positive breast cancers, and a focus on updating the (i) assessment, reporting and interpretation of ER immunohistochemical (IHC) staining, (ii) correlations of ER status with other diagnostic and theragnostic markers, and (iii) implications for treatment selection and response. In the face of the developments in IHC and molecular techniques and targeted therapy, ER immunostaining is still expected to remain as the core component of prognostic and theragnostic assessment of breast cancers.

Scoring Systems for Immunohistochemistry in Urothelial Carcinoma

Immunohistochemistry is widely used in diagnostic and scientific analysis of urothelial carcinoma. Objective interpretation of staining results is mandatory for accuracy and comparability in diagnostic and therapeutic patient care as well as research.Herein we summarize and explain standardized microscopic evaluation and scoring approaches for immunohistochemical stainings. We focus on commonly used and generally feasible approaches for different cellular compartments and comment on their utility in diagnostics and research practice.

Wnt Family Member 9b (Wnt9b) Is a Sensitive and Specific Marker for Triple-negative Breast Carcinoma Including Metaplastic Carcinoma

Wnt9b was recently identified as a highly sensitive and specific marker for breast carcinomas. Due to the limited number of triple-negative breast carcinomas (TNBCs) in previous study, we further explored Wnt9b's utility in breast carcinoma, especially in TNBCs including metaplastic carcinomas. We systematically evaluated Wnt9b expression on tissue microarrays (TMAs) from 413 breast carcinomas, 208 urothelial carcinomas, 102 endometrial carcinomas, 109 cholangiocarcinomas, 192 ovarian carcinomas, 48 lung adenocarcinomas, 69 colorectal adenocarcinomas, and 78 melanomas, and whole tissue section (WTS) from 20 human epidermal growth factor receptor 2-positive, 34 nonmetaplastic TNBCs, and 67 invasive metaplastic carcinomas. The results showed Wnt9b was highly expressed in breast carcinomas (91% on TMA and 98% on WTS) and in nonmetaplastic TNBCs (91% on TMA and 97% on WTS), but almost completely negative in other tested tumor types. Wnt9b was also highly expressed in metaplastic carcinomas (80%), significantly higher than GATA3 (56%) and SOX10 (48%), but slightly lower than TRPS1 (90%). In summary, our results demonstrate that Wnt9b is a highly sensitive marker for breast carcinomas, including TNBCs and metaplastic carcinomas. Further, we compared its utility with other breast markers including TRPS1, GATA3, and SOX10 in metaplastic carcinomas.