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]

GATA-3 expression in a de-differentiated chondrosarcoma with cutaneous iatrogenic implantation: a diagnostic pitfall with important clinical implications

De-differentiated chondrosarcoma (DDCS) is an extremely aggressive tumor of the bone characterized by a high-grade, non-chondroid sarcoma adjacent to a low- or intermediate-grade chondrosarcoma. Adequate tumor sampling demonstrating the biphasic features is necessary to make an accurate diagnosis. The diagnosis may be challenging as histopathology may mimic other neoplasms. We present a case of a 76-year-old woman with a history of breast cancer who presented with a pathologic non-displaced fracture. A bone biopsy demonstrated a high-grade neoplasm composed of pleomorphic spindled and epithelioid cells with focal expression of AE1/3 and GATA3, most likely consistent with metastatic breast carcinoma. After a difficult clinical course, the tumor was resected demonstrating a similar morphology to her prior biopsy, as well as an area of a low-grade cartilaginous neoplasm consistent with chondrosarcoma. The biphasic tumor alongside a low-grade chondrosarcoma allowed for a diagnosis of DDCS. Several days after her procedure, the patient developed violaceous nodules overlying and surrounding the surgical site. Skin biopsy demonstrated a malignant epithelioid neoplasm with identical histomorphologic features identical to her prior bone resection. Given the location of the skin lesions directly within the surgical site right after resection, the clinical-pathological picture was that of sarcomatosis cutis by iatrogenic cutaneous implantation.

GATA binding protein 3 (GATA3) as a marker for metaplastic spindle cell carcinoma of the breast

Spindle cell lesions of the breast comprise a diverse set of tumors; harboring significant histological and immunohistochemical (IHC) overlap. Accurate diagnosis and classification of spindle cell lesions in the breast remains challenging, especially in core biopsies. In the current study, we evaluated a spectrum of spindle cell lesion of the breast with a panel of IHC antibodies in an effort to differentiate metaplastic spindle cell carcinoma from its benign and malignant mimickers. Our study included 92 patients who underwent breast core biopsies or breast resections at Northwell Health who were diagnosed with benign and malignant tumor/tumor-like spindle cell lesions. Tumors subtypes in this the study included: angiosarcoma, nodular fasciitis, fibromatosis, myofibroblastoma, phyllodes tumors (benign, borderline and malignant), primary sarcomas and metaplastic spindle cell carcinoma. Our biomarker panel included high molecular weight keratin (HMWK), CAM5.2, AE1/AE3, p63, CD34 and GATA3. GATA3 expression was significantly higher in metaplastic carcinomas (88.9 % vs 4.1 %, p < 0.001), when compared to other spindle cell lesions. The sensitivity and specificity for detecting metaplastic carcinomas reached 84.2 % and 97.3 %, respectively. Regarding cytokeratin panels, none of the three individual markers were as sensitive or specific for metaplastic breast carcinoma. GATA3 is the most specific and sensitive marker forfor the identification of metaplastic spindle cell carcinoma of the breast.

Development and Carcinogenesis: Roles of GATA Factors in the Sympathoadrenal and Urogenital Systems

The GATA family of transcription factors consists of six proteins (GATA1-6) that control a variety of physiological and pathological processes. In particular, GATA2 and GATA3 are coexpressed in a number of tissues, including in the urogenital and sympathoadrenal systems, in which both factors participate in the developmental process and tissue maintenance. Furthermore, accumulating studies have demonstrated that GATA2 and GATA3 are involved in distinct types of inherited diseases as well as carcinogenesis in diverse tissues. This review summarizes our current knowledge of how GATA2 and GATA3 participate in the transcriptional regulatory circuitry during the development of the sympathoadrenal and urogenital systems, and how their dysregulation results in the carcinogenesis of neuroblastoma, renal urothelial, and gynecologic cancers.

Metastasis from tongue squamous cell carcinoma to the kidney

Metastasis to the kidney from other primary sites is extremely rare. Previous studies reported the lung as the most common primary site. Distant metastasis from the tongue to the kidney is exceedingly rare. Herein, we describe a case of metastatic squamous cell carcinoma to the kidney in a 71-year-old male with a detailed discussion of differentiating it from potential mimickers. The patient underwent a total glossectomy and bilateral cervical lymph node dissection. A diagnosis of well-differentiated squamous cell carcinoma of the tongue was rendered and the tumor was staged pT3 pN3b. Within two years of initial presentation, the patient developed widely metastatic disease, including pulmonary nodules, renal masses, left adrenal mass, and pancreatic mass. Accurate diagnosis of a secondary involvement of the kidney by a metastatic tumor requires the appropriate correlation of clinical and imaging findings as well as morphologic and immunohistochemical clues.

Perforating duodenal ulcer with umbilical herniation as a metastatic complication of primary signet ring cell carcinoma of the breast

Primary signet ring cell carcinoma (SRCC) of the breast is extremely rare, and the associated patterns of metastatic dissemination poorly described. Here, we report the case of a 61-year-old woman presenting with acute abdominal pain. Esophagogastroduodenoscopy revealed a non-bleeding erosive gastropathy, which was biopsied and found significant for a poorly differentiated, GATA3-positive SRCC. The patient was lost to follow up until re-presenting 6 months later with a perforating duodenal ulcer and umbilical herniation. Biopsies of umbilical hernia sack contents were significant for an estrogen receptor (ER) positive SRCC, and breast examination identified a right breast mass significant for an ER positive lobular carcinoma with signet ring features, thereby affirming the diagnosis of metastatic SRCC of the breast. This case offers insight into an advanced form of a rare clinical entity, and suggests that staining for breast markers such as GATA3 should be considered for all biopsies significant for SRCC.

Immunochemistry in the work-up of mesothelioma and its differential diagnosis and mimickers

The differential diagnosis in cellular effusions with cytological atypia often includes malignant mesothelioma (MM), reactive mesothelial proliferation, and malignancies of metastatic origin, particularly carcinomas. The International Reporting System for Serous Fluid recently established guidelines for reporting MM. In conjunction with the cytomorphologic evaluation, the role of immunochemistry (IC) was emphasized as a very useful tool in the workup of serous fluids, especially with the availability of novel markers. Utilizing a panel of markers, IC allows the characterization of the cells, whether mesothelial or not, and when mesothelial origin is established, IC can frequently assist in delineating its benign or malignant nature. IC can also confirm metastatic disease, allowing the identification of the primary origin in most cases. This review summarizes the current status of IC and its role in the diagnosis of MM and its differential diagnosis in serous fluids.

Gastrointestinal Bleeding Secondary to Metastatic Duodenal Choriocarcinoma in a Patient with Concomitant Peptic Ulcer Disease

Testicular tumors are one of the most common solid tumors in young males. Choriocarcinoma usually presents as metastatic disease. Gastrointestinal tract involvement is rare. We report a case of a 40-year-old male presenting to our hospital with a three-day history of dyspnea on exertion and black stool after recent diagnosis of testicular choriocarcinoma. Urgent EGD performed revealed small clean-based fundal ulcer and an antral ulcer without the stigma of recent bleeding. Capsule endoscopy was performed and revealed a bleeding ill-defined mass in the proximal duodenum. A subsequent push enteroscopy showed an ulcerated bleeding mass in the third part of the duodenum that was treated with a hemospray with adequate hemostasis. Pathology was consistent with pure choriocarcinoma. The patient received a cisplatin-based chemotherapy regimen. The patient tolerated the chemotherapy regimen well and was discharged for outpatient follow-up. At the three-month follow-up, the patient did not show evidence of recurrent gastrointestinal bleeding.

Endosalpingiosis Is Negative for GATA3

CONTEXT.—

Endosalpingiosis is a benign Müllerian inclusion that can mimic metastatic low-grade mammary carcinoma, particularly when encountered in axillary lymph nodes excised for breast cancer staging. Immunohistochemistry can be useful in histologically ambiguous cases, and a targeted immunopanel should include a marker of gynecologic tract origin and a marker of mammary origin. GATA3 is a sensitive immunomarker for breast carcinoma, but the immunoreactivity of GATA3 in endosalpingiosis has not been systematically evaluated.

OBJECTIVE.—

To evaluate whether GATA3 immunohistochemistry could be used to differentiate endosalpingiosis from metastatic mammary carcinoma.

DESIGN.—

Whole slide sections of 15 cases of endosalpingiosis involving nonneoplastic tissues were subjected to GATA3 immunohistochemistry. Nuclear GATA3 labeling was scored as percentage and intensity labeling, with any labeling considered positive; GATA3 labeling was recorded in all cells present in the sections.

RESULTS.—

Half (47%, n = 7 of 15) of the endosalpingiosis cases involved lymph nodes (2 axillary, 5 pelvic) and half (53%, n = 8 of 15) involved pelvic organs or soft tissue (3 myometrial, 2 paratubal, 2 periadnexal soft tissue, and 1 pelvic sidewall). GATA3 immunohistochemistry was negative in all cases of endosalpingiosis, with intact, positive control labeling in lymphocytes. The benign fallopian tube epithelium present on the sections of paratubal endosalpingiosis displayed focal (<5%), weak labeling for GATA3, specifically within the ciliated and secretory cells.

CONCLUSIONS.—

These findings support the diagnostic utility of GATA3 immunohistochemistry and its use in a targeted immunopanel to resolve the differential diagnosis of metastatic low-grade mammary carcinoma (GATA3+) and nodal endosalpingiosis (GATA3-).

GATA3 is a useful immunohistochemical marker for distinguishing sarcomatoid malignant mesothelioma from lung sarcomatoid carcinoma and organizing pleuritis

Sarcomatoid malignant mesothelioma (SMM) tends to occur in the pleura and is morphologically similar to lung sarcomatoid carcinoma (LSC) and organizing pleuritis (OP). Because SMM often does not express mesothelial markers, it is very difficult to distinguish from LSC and OP. GATA-binding protein 3 (GATA3) is a specific immunohistochemical (IHC) marker of breast and urothelial carcinoma. We routinely find that GATA is expressed in MM; however, GATA3 expression in SMM and its reference value for distinguishing SMM from LSC and OP remain unclear. Here, we used IHC methods to detect the expression of GATA3 and classic mesothelial markers in 17 SMM, 12 LSC, and 7 OP cases. We detected the following expression rates in SMM versus LSC cases: GATA3 (70.6% vs. 16.7%, p = 0.008), calretinin (52.9% vs. 8.3%, p = 0.019), Wilms tumor (WT)-1 (64.7% vs. 0%, p = 0.000), D2-40 (47.1% vs. 16.7%, p = 0.126), CK5/6 (35.3% vs. 25.0%, p = 0.694), and pan-cytokeratin (CKpan) (88.2% vs. 100.0%, p = 0.498). The specificities of calretinin, WT-1, and GATA3 in distinguishing SMM from LSC were 91.7%, 100%, and 83.3%, respectively, and combinations of any two of these three markers exhibited 100% specificity for SMM. Notably, the sensitivity of calretinin+/WT1+ staining for SMM was only 23.5%, which increased to 64.7% after including GATA3. Furthermore, all OP cases showed partial or diffuse expression of CKpan, WT-1, and D2-40 but no GATA3 and calretinin expression. In conclusion, GATA3 is an IHC marker with excellent sensitivity and specificity for SMM, and the combined consideration of GATA3, calretinin, and WT-1 was best for distinguishing SMM from LSC. Moreover, CKpan, WT-1, and D2-40 had no value for distinguishing SMM from OP, and GATA3 and calretinin were the most specific markers for distinguishing these two lesions.

Pathology of Malignant Pleural Mesothelioma

Despite multiple diagnostic toolkits, the diagnosis of diffuse malignant pleural mesothelioma relies primarily on proper histologic assessment. The definitive diagnosis of diffuse malignant pleural mesothelioma is based on the pathologic assessment of tumor tissue, which can be obtained from core biopsy sampling, pleurectomy, or other more extensive resections, such as extrapleural pneumonectomy. Given its rarity and overlapping microscopic features with other conditions, the histologic diagnosis of diffuse malignant pleural mesothelioma is challenging. This review discusses the pathologic features and the differential diagnosis of diffuse malignant pleural mesothelioma, including select diagnostic pitfalls.

Cytokeratin 7, GATA3, and SOX-10 is a Comprehensive Panel in Diagnosing Triple Negative Breast Cancer Brain Metastases

Following lung cancer, breast cancer is the second most common metastatic tumor to the brain, of which triple-negative breast cancer (TNBC) and human epidermal growth factor receptor 2+ (HER2+) breast cancer are the most common subtypes. TNBC does not have standard immunoprofiles and can be difficult to distinguish from other metastases. A tissue microarray was created from 47 patients with breast cancer metastases to the brain and 12 paired breast primaries. Of 47 breast cancer metastases, 24 were HER2+, 14 were TNBC, and 9 were luminal. Forty-five were cytokeratin 7 (CK7) positive, 36 were GATA-binding protein 3 (GATA3) positive, 7 were Sry-related HMg-Box gene 10 (SOX-10) positive, 20 were mammaglobin positive, and 19 were gross cystic disease fluid protein 15 positive. At least one of the CK7, GATA3, or SOX-10 was positive in all TNBC metastases. A panel of CK7, GATA3, and SOX-10 is complementary in the diagnosis of breast cancer brain metastasis. SOX-10 appears to be a specific but not particularly sensitive marker in this context.

In Situ Characterization of Follicular Helper CD4 T Cells Using Multiplexed Imaging

Follicular helper CD4 T (Tfh) cells play an essential role in the formation of germinal centers (GCs), where mature B cells proliferate, differentiate, and provide long-term protective humoral responses. Despite the extensive phenotypic characterization and identification of human Tfh cell subsets, their spatial positioning at tissue level is not well understood. Here, we describe a quantitative multiplexed immunofluorescence approach allowing for the comprehensive in situ characterization of Tfh cells in human tonsils and lymph nodes (LNs) from individuals with angioimmunoblastic T-cell lymphoma (AITL). We have developed eight multiplexed panels comprising a spectrum of Tfh cell markers, like PD-1, CXCR5, and ICOS, along with transcription factors (Bcl6, Tbet, GATA3), to assess their expression, frequencies, spatial distribution and co-localization in a quantitative manner. Combined analysis of relevant markers revealed the presence of several Tfh cell subsets at tissue level based on the differential expression of surface receptors, nuclear factors as well as their distinct localization within the follicular areas. Interestingly, we found a considerable amount of tonsillar Tfh cells expressing high levels of the Th2 regulator GATA3. The co-expression of GATA3, CXCR5, and BCL6, points to an important role of GATA3 for the generation of effector human Tfh cells. Furthermore, our data revealed significantly different Tfh cell profile signatures between health and disease. Therefore, our imaging platform generates meaningful information for the in situ characterization of human Tfh cells and could provide the base for future studies aiming to a comprehensive understanding of Tfh cell tissue heterogeneity.

Cancer of Unknown Primary: Challenges and Progress in Clinical Management

Distant metastases are the main cause of cancer-related deaths in patients with advanced tumors. A standard diagnostic workup usually contains the identification of the tissue-of-origin of metastatic tumors, although under certain circumstances, it remains elusive. This disease setting is defined as cancer of unknown primary (CUP). Accounting for approximately 3-5% of all cancer diagnoses, CUPs are characterized by an aggressive clinical behavior and represent a real therapeutic challenge. The lack of determination of a tissue of origin precludes CUP patients from specific evidence-based therapeutic options or access to clinical trial, which significantly impacts their life expectancy. In the era of precision medicine, it is essential to characterize CUP molecular features, including the expression profile of non-coding RNAs, to improve our understanding of CUP biology and identify novel therapeutic strategies. This review article sheds light on this enigmatic disease by summarizing the current knowledge on CUPs focusing on recent discoveries and emerging diagnostic strategies.

Pleural mesothelioma classification update

The 2015 WHO classification of pleural mesotheliomas includes three major histologic subtypes-epithelioid, sarcomatoid, and biphasic. Recent genomic data has supported the need for a more granular and clinically valid classification beyond the three current subtypes. Because of tumor rarity and overlapping histologic features with other tumor types, diagnostic immunohistochemical work up is essential component in establishing the final diagnosis of mesothelioma. The use of BAP1 and CDKN2A/MTAP improves the diagnostic sensitivity of effusion specimens and are valuable in establishing the diagnosis of epithelioid mesothelioma. The major change in the forthcoming WHO classification is the inclusion of mesothelioma in situ as a diagnostic category. In this review, we discuss recently proposed changes in the histologic classification of pleural mesothelioma, differential diagnosis, and importance of ancillary diagnostic studies.

Immunohistochemistry of mammary Paget's disease. Cytokeratin 7, GATA3, and HER2 are sensitive markers

OBJECTIVES

To investigate the expression of various immunohistochemical markers in Mammary Paget's disease (MPD) and MPD-associated breast carcinoma and to evaluate their value in establishing the diagnosis.

METHODS

This retrospective descriptive study was carried out at King Faisal Specialist Hospital and Research Center and King Khalid University Hospital, Riyadh, Saudi Arabia. All MPD cases reported between January 2010 and June 2016 were selected from the surgical pathology records.  Immunohistochemical staining was carried out for cytokeratin 7 (CK7), GATA-binding protein 3 (GATA3), human epidermal growth factor receptor 2 (HER2), and estrogen, and progesterone receptors. Results: Twenty-two cases of MPD and 20 cases of MPD-associated breast carcinoma were included. CK7 was positive in 95% (21/22) cases of MPD and in all (20/20) cases of associated breast carcinoma. Similarly, GATA3 was expressed in 95% cases of both MPD (21/22) and associated breast carcinoma (19/20). Human epidermal growth factor receptor 2 was also overexpressed in 90% cases of MPD (20/22) and associated breast carcinoma (18/20). Estrogen stained positive in 27% cases of MPD (6/22) and 30% of cases of associated breast carcinoma (6/20). Progesterone receptors was not positive in any case of MPD; however, it was seen positive in 25% cases of MPD-associated breast carcinoma (5/20).

CONCLUSIONS

CK7, GATA3, and HER2 are widely expressed in MPD and MPD-associated breast carcinoma. These markers can be used for the immunohistochemical confirmation of MPD including CK7-negative cases.

A Rare Case of GATA3 Positivity in Pleomorphic Lung Carcinoma in a Patient with History of Intracystic Papillary Carcinoma of the Breast: Primary Lung or Metastatic Disease?

Pleomorphic lung carcinoma is a rare and aggressive neoplasm accounting for <1% of all lung tumors. It is more common in men and consists of spindle and/or giant cells with an epithelial component. In patients with known histories of malignancies at other sites, diagnosis of a new lung lesion may prove challenging with respect to classification as either primary or metastatic disease, especially in cases with overlapping immunohistochemical staining patterns. This was a case of a 67-year-old female with a newly discovered 1.5 cm nodule in her left lower lung lobe. Her past medical history was significant for an intracystic papillary carcinoma of the right breast diagnosed 8 years prior. Histopathologic examination of the new lung lesion revealed highly pleomorphic cells composed predominantly of neoplastic giant cells and atypical mitotic figures, with geographic areas of necrosis. However, no areas reminiscent of intracystic papillary carcinoma or other forms of breast carcinoma were seen. Immunohistochemistry showed that the tumor cells were immunoreactive for GATA3, TTF1, and napsin A and nonimmunoreactive for p40. Therefore, although this index lung tumor did show positivity with GATA3 staining, it was morphologically different from her original intracystic papillary carcinoma of the breast. In addition, intracystic papillary carcinomas are known to rarely metastasize to other organs, and GATA3 staining has been rarely reported in lung carcinomas. In summary, this case typifies the overlapping immunohistochemical staining patterns that may be seen in different tumors and the role of histopathologic morphology in arriving at the correct diagnosis.

GATA3 somatic mutations are associated with clinicopathological features and expression profile in TCGA breast cancer patients

The effect of somatic mutations and the gene expression profiles on the prognosis is well documented in cancer research. This study was conducted to evaluate the association of GATA3 somatic mutations with tumor features, survival, and expression profiles in breast cancer. Clinicopathological information was compared between TCGA-BRCA patients with GATA3-mutant and non-mutant tumors in all patients as well as in ER-positive subgroup. Cox-regression method was used to evaluate the association of the GATA3 mutation status with overall survival time. Differential gene expression, functional annotation, and protein-protein interaction analyses were performed using edgeR, Metascape, DAVID, STRING and CytoNCA. GATA3-mutant and non-mutant samples had significantly different clinicopathological features (p < 0.05). While GATA3 mutation status was not associated with the overall survival in the entire cohort (p_adj = 0.52), the GATA3-wild type ER-positive cases had a better prognosis than mutant ones (p_adj = 0.04). GATA3 expression was higher in tumors than normal tissues. Several pathways were different between mutant and non-mutant groups (p < 0.05). Interleukin-6 was found as the highest scored gene in both comparisons (normal vs. mutant and normal vs. non-mutant groups) in the entire patient and in the ER-positive subgroup, suggesting the association of IL6 with breast tumorigenesis. These findings suggest that GATA3 mutations can be associated with several tumor characteristics and influence the pattern of gene expression. However, GATA3 mutation status seems to be a prognostic factor for the disease only in ER-positive patients.

Salivary Duct Carcinoma: An Aggressive Salivary Gland Carcinoma with Morphologic Variants, Newly Identified Molecular Characteristics, and Emerging Treatment Modalities

Salivary duct carcinoma (SDC) is a rare, aggressive salivary gland malignancy with significant mortality. Morphologically, most tumors are characterized by apocrine differentiation with a typical immunophenotype of androgen receptor positive/gross cystic disease fluid protein positive/estrogen receptor negative/progesterone receptor negative. Several morphologic variants of SDC exist, representing diagnostic pitfalls. Several differential diagnoses should be considered because prognosis, treatment, and management may be different from SDC. For SDC, current treatment strategies are aggressive and commonly include surgical excision with lymph node dissection and adjuvant radiotherapy. Continued research is examining the utility of androgen deprivation therapy and targeted molecular therapy.

Malignant Mesothelioma of the Peritoneum in Women: A Clinicopathologic Study of 164 Cases

Malignant mesothelioma of the peritoneum in women is an uncommon tumor. In this study, we present the clinicopathologic features of 164 such cases seen in our institution over a period of 42 years (1974-2016). Clinical information, pathologic findings, immunohistochemical results, and follow-up were recorded. Hematoxylin and eosin-stained slides were reviewed in all cases. Patients ranged in age from 3 to 85 years, median: 49 years. Most patients presented with abdominal/pelvic pain, although some were asymptomatic, presented with paraneoplastic syndromes or cervical lymphadenopathy. Overall, 9% of patients had a history of direct or indirect exposure to asbestos. In total, 31% and 69% of patients had either a personal or family history of other tumors; most of these tumors are currently recognized as part of a syndrome. Genetic testing information was available in 5 patients: BAP-1 germline mutation (1), type 2 neurofibromatosis (1), Lynch syndrome (1), McCune-Albright syndrome (1), no BAP-1 or TP53 mutation (1). Most cases had gross and microscopic features typical of malignant mesothelioma of the peritoneum in women; however, some had confounding features such as gelatinous appearance, signet ring or clear cells, and well-differentiated papillary mesothelioma-like areas. Calretinin and WT-1 were the markers more frequently expressed, and up to 23% of the cases showed PAX-8 expression. Patients' treatments predominantly included: chemotherapy, cytoreductive surgery, and hyperthermic intraperitoneal chemotherapy. On multivariate analysis, the predominance of deciduoid cells, nuclear grade 3, and the absence of surgical treatment were associated with worse overall survival (OS). For all patients, the 3- and 5-year OS were 74.3% and 57.4%, respectively. The 3- and 5-year OS for patients treated with cytoreductive surgery, and hyperthermic intraperitoneal chemotherapy were 88.9% and 77.8%, respectively.

Novel uses of immunohistochemistry in breast pathology: interpretation and pitfalls

Immunohistochemistry is an essential component of diagnostic breast pathology. The emergence of novel assays and applications is accompanied by new interpretation criteria and potential pitfalls. Immunohistochemistry assists in supporting breast origin for primary or metastatic carcinomas and identifying non-mammary metastases to the breast; however, no single immunostain is perfectly sensitive nor specific. GATA3 and Sox10 are particularly useful immunostains to identify triple negative breast carcinoma, which are often negative for other markers of mammary differentiation. Sox10 labeling is a major potential diagnostic pitfall, as Sox10 and S-100 label both triple negative breast carcinoma and metastatic melanoma; a pan-cytokeratin immunostain should always be included for this differential diagnosis. Novel immunohistochemistry serves as surrogates for the molecular alterations unique to several of special-type breast carcinomas, including the use of MYB in adenoid cystic carcinoma, pan-TRK in secretory carcinoma, and mutant IDH2 in tall cell carcinoma with reversed polarity (TCCRP). In addition, PD-L1 immunohistochemistry is an emerging, albeit imperfect, biomarker for breast cancer immunotherapy, with different assay parameters and scoring criteria in breast carcinoma compared to other tumor types. The expanding repertoire of novel immunohistochemistry provides additional diagnostic tools and biomarkers that improve diagnostic breast pathology and patient care.

Peritoneal Metastasis After Treated With Abemaciclib Plus Fulvestrant for Metastatic Invasive Lobular Breast Cancer: A Case Report and Review of the Literature

Peritoneal metastases from invasive lobular carcinoma (ILC) of breast are uncommon and usually related to poor prognosis due to difficulty of detection in clinical practice and drug resistance. Therefore, recognizing the entities of peritoneal metastases of ILC and the potential mechanism of drug resistance is of great significance for early detection and providing accurate management. We herein report a case of a 60-year-old female who presented with nausea and vomiting as the first manifestation after treated with abemaciclib (a CDK4/6 inhibitor) plus fulvestrant for 23 months due to bone metastasis of ILC. Exploratory laparotomy found multiple nodules in the peritoneum and omentum, and immunohistochemistry confirmed that the peritoneal metastatic lesions were consistent with ILC. Palliative therapy was initiated, but the patient died two months later due to disease progression with malignant ascites. Whole exome sequencing (WES) was used to detect the tumor samples and showed the peritoneal metastatic lesions had acquired ESR1 and PI3KCA mutations, potentially explaining the mechanism of endocrine therapy resistance. We argue that early diagnosis of peritoneal metastasis from breast cancer is crucial for prompt and adequate treatment and WES might be an effective supplementary technique for detection of potential gene mutations and providing accurate treatment for metastatic breast cancer patients.

Correlation of MSH2 exonic deletions and protein downregulation with breast cancer biomarkers and outcome in Pakistani women/patients

Mismatch repair (MMR) pathway is one of the underlying mechanisms of predisposition to breast cancer (BC). The present study explored the association of MSH2 exonic deletions, respective survival analysis, protein structure prediction, transcription profiling, and expression analysis with BC risk. Genotyping analysis of 493 BC cases and 387 controls confirmed the association of two MSH2 exonic deletions, i.e., exon 3 (OR:6.4, CI = 3.4-12.1) and 9 (OR:7.8, CI = 4.1-14.8) with BC risk. In order to confirm the phenotypic-genotypic relationship, we have performed MSH2 transcriptomic (p < 0.05) and protein expression analysis (OR:30, CI = 4-230) which further confirmed its downregulation/loss in BC biopsy samples highlighting potential role in the onset of breast carcinogenesis. Additionally, we have presented that MSH2 mutations can alter the expression profile of other BC associated biomarkers like ER, PR, CK-7, GATA-3, and E-cadherin. Subsequently, the effect of exonic deletions on secondary structure of protein has shown missing of beta and alpha helices in their protein products via in-silico analysis. However, loss of exon 3 results in the altered core protein structure leading to dysfunction protein, possible cause of BC development. No association of MSH2 exonic deletions with survival statistics was observed conceivably due to the shorter follow-up time. Thus, our results at genetic, transcriptomic, and proteomic levels confirmed the downregulated MSH2, emphasizing its potential contribution in MMR mechanisms for breast tumorigenesis. In conclusion, MSH2 deficiency may cause breast cancer development and progression.

Association Between Estrogen Receptors and GATA3 in Bladder Cancer: A Systematic Review and Meta-Analysis of Their Clinicopathological Significance

BACKGROUND

Estrogen receptors alpha (ERα) and beta (ERβ) and the cooperating protein GATA-binding factor 3 (GATA3) have been implicated in bladder carcinogenesis and tumour progression. GATA3 and ER have been functionally linked in the establishment of luminal fate in breast tissue, but to date their relationship in bladder cancer has not been established. This information will be useful to advance diagnostic and prognostic markers.

AIM

To determine the relationship between the expression of ERα, ERβ and GATA3 in bladder cancer, disclose their prognostic and diagnostic value and their association with clinicopathological characteristics.

METHODS

A comprehensive literature search in PubMed database was performed for all immunohistochemical studies of ERα, ERβ and/or GATA3 in bladder cancer patients. We selected eligible studies in accordance with the PRISMA guidelines and evaluated methodological quality and risk of bias based on quality criteria from the reporting recommendations for tumour MARKer (REMARK) prognostic studies. Risk of bias assessment was performed using Review Manager 5. R software was used for all statistical analysis, the packages used were meta and dmetar for the standard meta-analysis, and netmeta for the network meta-analysis.

RESULTS

Thirteen studies were eligible for ERα, 5 for ERβ and 58 for GATA3 meta-analysis. Low grade tumours showed significantly lower ERα expression. GATA3 was widely expressed in bladder tumours, especially urothelial carcinomas, with higher expression of GATA3 in low grade and low stage tumours. Data was insufficient to determine the prognostic value of either ERα or ERβ, but GATA3-positivity was associated with higher recurrence free survival. A negative correlation between ERα or ERβ positivity and GATA3 expression was disclosed. Additionally, several sources of heterogeneity were identified, which can be used to improve future studies.

CONCLUSION

The clinicopathological value of ERα and ERβ was inconclusive due to low availability of studies using validated antibodies. Still, this meta-analysis supports GATA3 as good prognostic marker. On the contrary, ERα-positivity was associated to higher grade tumours; while ERα and ERβ were inversely correlated with GATA3 expression. Considering that it has previously been shown that bladder cancer cell lines have functional ERs, this suggests that ERα could be activated in less differentiated cells and independently of GATA3. Therefore, a comprehensive analysis of ERα and ERβ expression in BlaCa supported by complete patient clinical history is required for the identification of BlaCa subtypes and subgroups of patients expressing ERα, to investigate if they could benefit from treatment with hormonal therapy.

SYSTEMATIC REVIEW REGISTRATION

Prospero, CRD42021226836.

Clinical Applications of Immunohistochemistry in Germ Cell Tumors in Men

Germ cell tumors (GCT) in men comprise of tumor subtypes with distinct histomorphologies, genetic and genomic alterations, and clinical behavior. Immunohistochemical (IHC) markers, including many newly described nuclear transcription factors, are often applied in challenging cases to arrive at a correct diagnosis and classification, and to establish germ cell origin for metastatic tumors. However, there is no established role for IHC markers in prognosis and therapy response prediction in GCTs. This chapter briefly reviews the clinical utility of IHC in diagnosis and classification of GCTs, including technical aspects of performing IHC and clinical applications of commonly used IHC markers in the workup of common and clinically relevant diagnostic scenarios.

Metastatic Epithelial-Myoepithelial Carcinoma in a Female Presenting with Neck Mass and Lytic Lesion in Acetabulum: A Diagnostic Challenge on Cytology

Epithelial-myoepithelial carcinoma (EMC) is a rare, low-grade, malignant salivary neoplasm. Establishing an accurate cytological diagnosis is often challenging owing to its rarity, bland cytologic appearance and variable representation of cell populations in the smears. The diagnostic struggle is more so when the aspiration is from a metastatic site with an unknown primary, as in such cases the list of differential diagnoses expands further. A 58-year-old female presented with a low-back pain from last one month. On examination, she also had a level III, right cervical swelling for the last 20 years. Radiology revealed a lytic lesion in the left acetabulum. She had undergone surgery 35 years ago for a right-sided upper neck swelling, the medical records of which were not available. Fine needle aspiration (FNA) from the cervical swelling was performed. The smears were cellular and showed predominantly dispersed, round to polygonal tumor cells with mild pleomorphism, eccentric nuclei, coarse chromatin, occasional nucleoli and moderate cytoplasm with some showing vacuolations. The cell-block section revealed tumor cells arranged in the form of tubules lined by dual layer of tumor cells without any chondromyxoid stroma. On immunocytochemistry, the luminal cells showed positivity for CK7 (epithelial marker) and the abluminal cells showed positivity for p63 (myoepithelial marker). Based on these features, a final diagnosis of metastatic epithelial-myoepithelial carcinoma was rendered. The present report highlights the characteristic cytomorphological and immunocytochemical features of EMC and reiterates the diagnostic accuracy of FNAC for diagnosis of such challenging cases.

Comprehensive guidance on the diagnosis and management of primary mesenchymal tumours of the thyroid gland

Most primary thyroid tumours are of epithelial origin. Primary thyroid mesenchymal tumours are rare but are being increasingly detected. A vast majority of thyroid mesenchymal tumours occur between the fourth and seventh decades of life, presenting as progressively enlarging thyroid nodules that often yield non-diagnostic results or spindle cells on fine needle aspiration biopsy. Surgery is the preferred mode of treatment, with adjuvant chemoradiotherapy used for malignant thyroid mesenchymal tumours. Benign thyroid mesenchymal tumours have excellent prognosis, whereas the outcome of malignant thyroid mesenchymal tumours is variable. Each thyroid mesenchymal tumour is characterised by its unique histopathology and immunohistochemistry. Because of the rarity and aggressive nature of malignant thyroid mesenchymal tumours, a multidisciplinary team-based approach should ideally be used in the management of these tumours. Comprehensive guidelines on the management of thyroid mesenchymal tumours are currently lacking. In this Review, we provide a detailed description of thyroid mesenchymal tumours, their clinical characteristics and tumour behaviour, and provide recommendations for the optimal management of these tumours.

Incidence and significance of GATA3 positivity in gallbladder adenocarcinoma

GATA3 immunostaining is a sensitive marker for mammary and urothelial carcinomas. It is routinely used in surgical pathology during workup of carcinomas of unknown origin. To the best of our knowledge, this is the first focused study of GATA3 expression in gallbladder adenocarcinomas. In this study, we evaluated GATA3 expression in 38 gallbladder adenocarcinomas. Eight of 38 (21%) gallbladder adenocarcinomas were positive for GATA3. The expression of GATA3 tended to be moderate to strong when present. It was patchy (<50% positivity) in 4 cases, characterized by discrete clusters or groups of malignant cells with areas of intervening negative tumor cells, whereas it was diffuse (>50% positivity) in the other 4 cases. GATA3 expression did not show any significant correlation with clinicopathologic features such as sex, histologic grade, perineural invasion, vascular invasion, pathologic stage, or distance metastasis. The results of our study show that a subset of gallbladder adenocarcinomas (21%) can be GATA3 positive. Awareness of this phenomenon is important while working up GATA3-positive carcinomas immunohistochemically.

Coexpress of GATA-3 and ER in Anorectal and Head and Neck Squamous Cell Carcinoma Mimicking Metastatic Breast Cancer

GATA binding protein 3 (GATA-3) is a sensitive marker for breast and urothelial carcinomas. In combination with the estrogen receptor (ER), it is often used for differential diagnosis of metastatic carcinomas of breast origin. In this study, we sought to characterize GATA-3 and ER expression in squamous cell carcinoma (SqCC) of various origins to compare with breast carcinoma. Sixty-four SqCC of anorectum (35), head and neck (15), lung (11), and breast (3) as well as urothelial carcinoma (31) were included. In anorectal and head and neck SqCC, GATA-3, and ER was observed in 23/50 (46.0%) and 18/50 (36.0%) of the cases, respectively. The expression of GATA-3 and ER were present in both male and female patients without significant sex predominance. In 2 metastatic SqCC, the GATA-3 and ER expressed similar immunoreactivity compatible with their anorectal primary. Progesterone receptor was only expressed in 2 anorectal SqCC and none of head and neck SqCC or urothelial carcinomas. None of the lung SqCC expressed GATA-3 or ER (0/11). p16 was expressed in the majority of head and neck (6/12) and anorectal SqCC (26/27). Our study demonstrated that the combination of GATA-3 and ER positivity is not entirely specific for breast carcinomas, since both stains are expressed in SqCC from anorectal and head and neck origins. Clinical workup for metastatic carcinoma of suspicious breast origin should be cognizant of other tumors with a similar immunohistochemical profile (ie, SqCC).

Colon metastases as first clinical manifestation of lobular breast carcinoma with no subsequent evidence of breast disease

A 73-year-old woman was brought to the oestrogen receptor for altered mental status. She was found to be hypotensive and hypoglycaemic and admitted to the intensive care unit. She had a history of chronic watery diarrhoea which had recently increased over the last 2 weeks and was associated with vague abdominal pain. A CT showed bowel wall thickening concerning for colitis. Due to the increasing diarrhoea, a colonoscopy was done after all stool studies came back negative. Polyps in the ascending, transverse and sigmoid colon were found to be tubular adenomas but random colonic mucosa biopsies were revealed to be histologically consistent with metastatic lobular breast carcinoma. Further workup revealed no primary breast disease.

Role of immunohistochemistry in gynec oncopathology including specific diagnostic scenarios with associated treatment implications

Over the years, immunohistochemistry has emerged as a powerful tool for a more precise diagnosis of certain tumors in gynecologic oncopathology and resolving certain diagnostic dilemmas with significant treatment implications. Certain specific immunohistochemical (IHC) markers have been useful in the more correct identification of rare tumors, characterized by specific molecular signatures. Immunohistochemistry has also been useful in the identification of underlying genetic events, characterizing various tumors, as well as precancerous lesions. This review will focus upon the judicious application of various IHC antibody markers in gynec oncopathology, including authors' experience during "sign-outs" and especially during interaction with other oncology colleagues within the institutional disease management group. The updated references were retrieved from PubMed.

Whole-proteome analysis of mesonephric-derived cancers describes new potential biomarkers

Mesonephric carcinomas (MEs) and female adnexal tumors of probable Wolffian origin (FATWO) are derived from embryologic remnants of Wolffian/mesonephric ducts. Mesonephric-like carcinomas (MLCs) show identical morphology to ME of the cervix but occur in the uterus and ovary without convincing mesonephric remnants. ME, MLC, and FATWO are challenging to diagnose due to their morphologic similarities to Müllerian/paramesonephric tumors, contributing to a lack of evidence-based and tumor-specific treatments. We performed whole-proteomic analysis on 9 ME/MLC and 56 endometrial carcinomas (ECs) to identify potential diagnostic biomarkers. Although there were no convincing differences between ME and MLC, 543 proteins showed increased expression in ME/MLC relative to EC. From these proteins, euchromatic histone lysine methyltransferase 2 (EHMT2), glutathione S-transferase Mu 3 (GSTM3), eukaryotic translation elongation factor 1 alpha 2 (EEF1A2), and glycogen synthase kinase 3 beta were identified as putative biomarkers. Immunohistochemistry was performed on these candidates and GATA3 in 14 ME/MLC, 8 FATWO, 155 EC, and normal tissues. Of the candidates, only GATA3 and EHMT2 were highly expressed in mesonephric remnants and mesonephric-derived male tissues. GATA3 had the highest sensitivity and specificity for ME/MLC versus EC (93% and 99%) but was absent in FATWO. EHMT2 was 100% sensitive for ME/MLC & FATWO but was not specific (65%). Similarly, EEF1A2 was reasonably sensitive to ME/MLC (92%) and FATWO (88%) but was the least specific (38%). GSTM3 performed intermediately (sensitivity for ME/MLC and FATWO: 83% and 38%, respectively; specificity 67%). Although GATA3 remained the best diagnostic biomarker for ME/MLC, we have identified EHMT2, EEF1A2, and GSTM3 as proteins of interest in these cancers. FATWO's cell of origin is uncertain and remains an area for future research.

Immunohistological expression of oestrogen receptor, progesterone receptor, mammaglobin, human epidermal growth factor receptor 2 and GATA-binding protein 3 in non-small-cell lung cancer

AIMS

Non-small-cell lung cancer (NSCLC) and breast cancer are common entities. Staining for oestrogen receptor (ER), progesterone receptor (PgR), mammaglobin (MAMG) and GATA-binding protein 3 (GATA3) is frequently performed to confirm a mammary origin in the appropriate diagnostic setting. However, comprehensive data on the immunohistological expression of these markers in NSCLC are limited. Therefore, the aim of this study was to analyse a large cohort of NSCLCs and correlate the staining results with clinicopathological variables.

METHODS AND RESULTS

A tissue microarray was stained for ER, PgR, MAMG, human epidermal growth factor receptor 2 (HER2), and GATA3, and included 636 adenocarcinomas (ADCs), 536 squamous cell carcinomas (SqCCs), 65 large-cell-carcinomas, 34 pleomorphic carcinomas, and 20 large-cell neuroendocrine carcinomas. HER2 status was determined for immunohistochemically positive cases with chromogenic in-situ hybridisation. Markers with a proportion of ≥5% positive cases in ADC and SqCC were considered for survival analysis. Among ADCs, 62 (10%), 17 (3%), one (<1%), seven (1%), and 49 (8%) cases were positive for ER, PgR, MAMG, HER2, and GATA3, respectively. Among SqCCs, 10 (2%), 14 (3%), two (<1%) and 109 (20%) cases were positive for ER, PgR, HER2, and GATA3, but none of the samples showed positivity for MAMG. ER positivity was associated with ADC, female sex, smaller tumour size, and lower clinical stage. None of the markers had an impact on survival.

CONCLUSION

We report on ER, PgR, MAMG, HER2 and GATA3 expression in a large cohort of NSCLCs. Interpretation of these markers in the differential diagnostic setting should be based on a multimarker panel.

[E-Cadherine and GATA-3 are useful in the confirmation of the vas deferens in vasectomy specimens]

INTRODUCTION AND OBJECTIVES

Urologists often submit the resected tissue from vasectomies for histopathological examination in order to confirm the presence of the vas deferens. Microscopy is simple and based on haematoxylin-eosin staining; however, sample artefacts can sometimes cause confusion and immunohistochemistry can be used to identify the vas deferens.

MATERIALS AND METHODS

We investigated the utility of immunohistochemical analysis using E-cadherin and GATA-3 to confirm the presence of vas deferens epithelium in 110 vasectomy sections with different artefacts, using monoclonal antibodies and a multimer conjugated with peroxidase based technique; 5 renal arteries and 5 renal veins were stained as negative controls.

RESULTS

Membrane staining was observed for E-cadherin, which was moderate (2.7%) or strong (97.3%) in the vas deferens epithelium in all cases: 35 without artefacts, 7 with denuded epithelium, 56 with compressed/distorted epithelium, 8 with detached epithelium and 4 with displaced epithelium. GATA-3 showed moderate (31%) or strong (69%) nuclear staining in all cases, including the 76 with artefacts. In the control group, arteries and veins were negative for both markers in the endothelium, but GATA-3 occasionally stained lymphocytes in the blood vessel wall.

CONCLUSIONS

E-cadherin membrane positivity and GATA-3 nuclear expression are useful for the identification of the vas deferens in vasectomy samples containing artefacts. Vascular endothelium is negative for both markers and any possible GATA-3 staining of the lymphocytes in the blood vessel wall should not be misinterpreted.

Doxorubicin and Trifolium pratense L. (Red clover) extract synergistically inhibits brain and lung metastases in 4T1 tumor-bearing BALB/c mice

Trifolium pratense L. (Red clover-T. pratense) commonly consumed as a healthy beverage has been demonstrated to have various biological activities including antioxidant and anticancer effects. The aim of this study was to investigate the antimetastasis effects of doxorubicin (DOX) and T. pratense extract in 4T1 tumor-bearing BALB/c mice. In this study, 56 female BALB/c mice were randomly divided into seven groups (n = 8/group) to receive DOX and T. pratense extract in three different doses (100, 200, and 400 mg/kg/day) for 35 days. On day 36 after starting treatments, serum cytokines (IL-8 and IL-6) were measured. Immunohistochemical (IHC) staining was performed for GATA-3 in the brain and lung, and for CK5/6 in tumor tissues. Metastasis-related gene (matrix metalloproteinase-2 [MMP-2] and sirtuin-1 [SIRT-1]) expressions were also measured by real-time PCR. Our results showed that cotreatment with DOX and T. pratense extract improved stereological parameters (i.e., reduction in the volume of metastatic tumors) in the lung and brain and decreased the serum levels of inflammatory cytokines (IL-8 and IL-6). DOX and T. pratense extract synergistically down-regulated MMP-2 and up-regulated SIRT-1 genes, decreased the number of CK5/6-positive cells in tumor tissues, and inhibited metastasis of GATA-3-positive cells into the lung and brain. The combination of T. pratense extract and DOX synergistically inhibited the metastasis of 4T1 xenograft cells in a dose-dependent manner.

The tumour immune landscape and its implications in cutaneous melanoma

The field of tumour immunology has rapidly advanced in the last decade, leading to the advent of effective immunotherapies for patients with advanced cancers. This highlights the critical role of the immune system in determining tumour development and outcome. The tumour immune microenvironment (TIME) is highly heterogeneous, and the interactions between tumours and the immune system are vastly complex. Studying immune cell function in the TIME will provide an improved understanding of the mechanisms underpinning these interactions. This review examines the role of immune cell populations in the TIME based on their phenotype, function and localisation, as well as contextualising their position in the dynamic relationship between tumours and the immune system. We discuss the function of immune cell populations, examine their impact on patient outcome and highlight gaps in current understanding of their roles in the TIME, both in cancers in general and specifically in melanoma. Studying the TIME by evaluating both pro-tumour and anti-tumour effects may elucidate the conditions which lead to tumour growth and metastasis or immune-mediated tumour regression. Moreover, an in-depth understanding of these conditions could contribute to improved prognostication, more effective use of current immunotherapies and guide the development of novel treatment strategies and therapies.

GATA3-Positive Adnexal Adenocarcinoma: Report of a Confusing Case with a Potential Pitfall of Leading to a Misdiagnosis of Urothelial Carcinoma and a Review of Published Work

We describe a confusing case of GATA3-positive adnexal adenocarcinoma with a potential pitfall of leading to a misdiagnosis of urothelial carcinoma. A 62-year-old male presented with a subcutaneous nodule on the right lower abdomen around a scar from surgery for urothelial carcinoma in the right urinary tract, which had been resected 8 years previously. Histologically, atypical cells possessing ample cytoplasm and partial intracytoplasmic lumens were densely grouped in the subcutaneous expansive nodule and bilateral inguinal lymph nodes dissected. Decapitation secretion could not be seen. Neoplastic cells were positive for CK7, GATA3, and GCDFP15, and negative for CK5/6, CK20, p63, CD10, PAX8, HER-2, and uroplakin-II. Neoplastic cells in the urothelium and the metastasized lung were positive for CK7, CK5/6, and GATA3, and negative for CK20, p63, GCDFP15, and TTF-1. A variable level of GATA3 expression in malignant tumors with apocrine and eccrine differentiation should be recognized by dermatologists.

Predictive markers for pathological complete response after neo-adjuvant chemotherapy in triple-negative breast cancer

A combination of Sox10 and GATA3 was previously identified as a marker for metastatic triple-negative breast cancer (TNBC), but it is uncertain whether their expression is associated with pathological complete response (pCR) after neoadjuvant chemotherapy (NAC). This study investigates the predictive value of clinicopathological characteristics, as well as protein expression of Sox10, GATA3, p53 and p63, in a consecutive series of TNBC patients treated with NAC. Archived hematoxylin & eosin stained slides of core biopsies and resection specimens from 35 TNBC patients were reviewed. The following clinicopathological characteristics were determined at the biopsy level: age at diagnosis, cancer type, Nottingham grade, lympho-vascular invasion, syncytial growth, necrosis, clear cell differentiation, myxoid peritumor stroma, stromal tumor-infiltrating lymphocytes (sTILs) and presence of an in situ component. The MD Anderson residual cancer burden (RCB) score and corresponding RCB class were determined. Immunohistochemistry for Sox10, p53, GATA3 and p63 was performed at the biopsy level. sTILs, either as a continuous or as a dichotomous variable, were the only parameter that was significantly associated with pCR in univariable and multivariable analyses. Assessment of sTILs showed moderate to good interobserver agreement. High sTILs (≥40%) were significantly associated with increased pCR rates, and this association was observer-independent. This retrospective study of a consecutive community-based cohort of TNBC patients confirms that sTILs are a robust, observer-independent predictor for therapeutic response after NAC. The combination of Sox10, GATA3 and p53 immunoreactivity is unlikely to harbor any predictive value for pCR in TNBC.

Sry-related high-mobility-group/HMG box 10 (SOX10) as a sensitive marker for triple-negative breast cancer

AIMS

Confirmation of a breast origin for triple-negative breast cancer (TNBC) is sometimes problematic. The traditional breast markers GATA-binding protein 3 (GATA3), mammaglobin (MGB) and gross cystic disease fluid protein 15 (GCDFP15) have shown limitations in identifying TNBC. Here, we aimed to examine the diagnostic potential of the newly proposed TNBC marker, Sry-related high-mobility-group/HMG box 10 (SOX10).

METHODS AND RESULTS

We analysed and compared SOX10 expression with GATA3, MGB and GCDFP15 expression in a test cohort of 1838 invasive breast cancers (IBCs) by using tissue microarrays. The findings from the test cohort were further examined with a validation cohort of 42 TNBCs in whole sections. The overall expression rates of SOX10, GATA3, MGB and GCDFP15 were 6.9%, 83.1%, 47.0%, and 34.8%, respectively. Among the TNBCs within this cohort, the expression rates of SOX10, GATA3, MGB and GCDFP15 were 31.3%, 34.5%, 27.9%, and 25.2%, respectively. SOX10 was strongly associated with TNBC (P < 0.001), whereas all other traditional markers were associated with non-TNBC (P < 0.001 for all). In addition, SOX10 was more correlated to basal-like breast cancer (BLBC) (P = 0.001) than five-marker-negative subtype among the TNBCs. A high expression rate of SOX10 (81%) was confirmed in the validation cohort. Additionally, SOX10 expression was inversely correlated with GATA3 and GCDFP15 expression, so they may complement each other in TNBC detection. The SOX10-GATA3 combination yielded a sensitivity of 60.3% for TNBC detection in the test cohort.

CONCLUSION

SOX10 is a reliable marker for identifying TNBC, and complements GATA3. The SOX10-GATA3 combination may be used as a sensitive TNBC marker.

The potential utility of GATA binding protein 3 for diagnosis of malignant pleural mesotheliomas

Malignant pleural mesothelioma is associated with asbestos exposure and poor outcomes. The usefulness of immunohistochemistry for diagnosis of sarcomatoid mesothelioma, especially the desmoplastic type, is limited, and more effective markers are required. GATA binding protein 3 (GATA3) has been suggested as a diagnostic marker for sarcomatoid mesothelioma. The potential usefulness of GATA3 for prognostication and its clinical and pathological correlations in different subtypes of mesothelioma have not been evaluated. We investigated the immunohistochemical labeling and associations for GATA3, BRCA1-associated protein 1 (BAP1), and Ki67 labeling in three major histological types of pleural malignant mesotheliomas. We examined 149 clinically annotated malignant mesotheliomas and assessed associations of GATA3 expression with clinical variables and prognosis. In addition, we labeled 10 cases of fibrous pleuritis with GATA3, all of which were negative. GATA3 was positive in 75 of 149 (50%) mesotheliomas, with the highest incidence of labeling seen in the sarcomatoid subtype (73%), compared with the biphasic (50%) and epithelioid (40%), mesotheliomas. A total of eight desmoplastic mesotheliomas showed labeling with GATA3. Patients whose tumors had sarcomatoid histology showed poorer survival than those with the other subtypes (p < 0.001), but overall GATA3 labeling did not have a statistically significant association with survival (p = 0.602). There was no association of GATA3 labeling and BAP1 status or Ki67 index. Our study includes the largest cohort of mesotheliomas that has been labeled for GATA3 to date. GATA3 is a useful marker for sarcomatoid mesothelioma, including the desmoplastic subtype. Discordance in GATA3 and BAP1 labeling of epithelioid and sarcomatoid components in the biphasic subtype is not uncommon.

Integrated immunohistochemical and molecular analysis improves diagnosis of high-grade carcinoma in the urinary bladder of patients with prior radiation therapy for prostate cancer

Prostatic adenocarcinoma and urothelial carcinoma typically demonstrate distinct morphologic and immunohistochemical features. However, high-grade prostate and urothelial carcinomas sometimes show significant morphologic and immunohistochemical overlap, which can result in misdiagnosis and mistreatment. This diagnostic dilemma is particularly acute in patients previously treated with radiation and/or hormone therapy for prostate cancer, who later present with high-grade carcinoma in the urinary bladder. To address the diagnostic utility of integrated immunohistochemical and molecular analysis in this setting, we evaluated 25 high-grade carcinomas of the bladder for which morphologic features were deemed indeterminate. Our analysis included immunohistochemistry for urothelial markers (GATA3, p63, uroplakin II), prostate markers (NKX3.1, prostate specific antigen, P501S), androgen receptor (AR) and ERG, along with molecular characterization using capture-based next generation DNA sequencing. Immunohistochemical findings were concordant with the final integrated diagnosis in 21 (84%) cases. However, in three (12%) cases, immunohistochemistry supported a diagnosis of urothelial carcinoma, but molecular analysis identified the correct diagnosis of prostate cancer based on the presence of a TMPRSS2-ERG fusion. One case remained unclassifiable even after this integrated analysis. Notably, in 1 of 21 cases, the presence of a TERT promoter mutation and the absence of a TMPRSS2-ERG fusion would typically favor a diagnosis of urothelial carcinoma, but the aggregate immunohistochemical and molecular findings instead supported a diagnosis of microsatellite unstable prostatic adenocarcinoma with deep deletion of MSH2 and MSH6. Our findings highlight the importance of considering prostatic origin in high-grade carcinoma of the urinary bladder of patients with a history of treated prostate cancer, even when the immunohistochemical findings favor urothelial carcinoma. In a subset of cases, an approach that integrates immunophenotypic and molecular data may help correctly assign site of origin and prevent misdiagnosis that can result from overreliance on any individual immunohistochemical or molecular result.

Investigation of somatostatin receptor profile of neuroendocrine carcinomas of the breast

Carcinomas of the breast with neuroendocrine features are rare primary neoplasms positive for neuroendocrine markers. According to the WHO classification of tumours of the breast they are divided into three morphologically distinct categories. They comprise neuroendocrine tumour (NET), neuroendocrine carcinoma (NEC) and carcinoma with neuroendocrine differentiation (NED). The purpose of this study was to investigate for the first time the full spectrum of sstr expression status in breast carcinomas with neuroendocrine features. Fifteen primary breast carcinomas with histological and immunohistochemical neuroendocrine features were studied. Four of them were classified as NETs and two as NECs, and the remaining 9 as carcinomas with NED. All six types of somatostatin receptor (sstr) types (sstr1, sstr 2A, sstr2B, sstr3, sstr4 and sstr5) were investigated by immunohistochemistry. To assess the distribution and intensity of membranous receptor immunoreactivity, a four-scale scoring system was used. Overall predominant receptors were sstr2A, sstr2B, sstr3 and sstr5 showing the highest membranous staining scores 3+ and 2 + . The sstr1 was not detected. Given that carcinomas with neuroendocrine features represent distinct entities, patients with such tumours may benefit from sstr targeting therapies. Immunohistochemistry for sstrs can predict the effectiveness of administration of SST analogues to those patients, thus contributing to achieve the maximum therapeutic outcome, particularly in NETs and NECs with scores 2+ and 3 + .

Bayesian approach to interpreting somatic cancer sequencing data: a case in point

Cancer lineage/tissue-of-origin assignment in cancers of unknown primary remains a challenge even when aided by massively parallel sequencing. The stakes are high for patients as many contemporary therapeutic strategies are disease-specific, and the biological differences can influence the patients' responses. Herein, we provide an example of how Bayesian analysis can be used to merge data from clinical history, histology, immunohistochemistry (IHC) and cancer DNA sequencing to assist in tissue-of-origin assignment. Iterative Bayesian analysis is performed through a set of simple calculations to calculate the OR between the differential diagnoses. We illustrate a clinical case, where the distinction between a primary lung versus metastatic bladder cancer was aided meaningfully by iterative Bayesian analyses, incorporating IHC and sequencing data.

Excellent response to erlotinib in breast carcinoma with rare EGFR mutation-a case report

Triple negative breast carcinoma is a problematic subtype with poor outcomes. Many clinical trials are underway to find possible target to increase treatment options. Epidermal growth factor receptor (EGFR) has emerged as one such molecule which is over expressed in some of these patients and can be targeted by tyrosine kinase inhibitors. We describe a diagnostically challenging case of metastatic breast carcinoma, with extensive lung disease and poor Eastern Cooperative Oncology Group (ECOG) performance status, which expressed an uncommon EGFR mutation (Exon 21L861Q) and which benefitted from erlotinib following failure of all primary treatment modalities. The case uncovers the presence of these unusual mutations in breast carcinoma and highlights the importance of performing molecular analysis and the appropriate targeted therapy. This approach can be an important problem-solving tool, especially in cases where the patient is not fit for the other standard treatment options.

Secondary tumors of the bladder: A survival outcome study

The urinary bladder may be involved by a variety of secondary tumors that originate from other organs. Bladder secondary tumors are rare and may be mistaken as bladder primary tumors because of their overlapping morphologic features. To avoid the diagnostic pitfalls, we analyzed the clinicopathologic features of bladder secondary tumors in a large cohort of patients. Our patient cohort consisted of 45 females and 38 males with a mean age of 58.7 ± 15.4 years (range 10-87 years). The tumors involved the bladder via direct extension from adjacent organs (n = 42) and distant metastasis (n = 41). In females, the majority of secondary tumors originated from the gynecologic tract (n = 25), and other common origins included the colon/rectum (n = 5) and breast (n = 4). In males, the most common origin was the prostate (n = 18), followed by the colon/rectum (n = 4) and kidney (n = 3). 75.9% of the secondary tumors were adenocarcinoma (n = 63), and other common tumor types included sarcoma (n = 6), squamous cell carcinoma (n = 5), melanoma (n = 4), and neuroendocrine carcinoma (n = 3). 67.5% of patients (n = 56) died of the disease with a median overall survival of 23 months from the time of secondary involvement of the bladder. Patients with secondary tumors via direct extension had a median survival time of 20 months, which was not significantly different from that for patients with secondary involvement via distant metastasis (24 months) (p = 0.83). Median survival in cases with prostate primary was 20 months as compared to 23 months for all other tumor types (p = 0.68). The majority of secondary tumors are composed of adenocarcinoma, which highlights the importance of differentiating primary from secondary involvement in bladder adenocarcinoma. Regardless of the origin, bladder secondary tumors are associated with a poor prognosis.

Napsin A is a highly sensitive marker for nephrogenic adenoma: an immunohistochemical study with a specificity test in genitourinary tumors

Nephrogenic adenomas are uncommon benign lesions that are typically cytologically bland, but degenerative and reactive changes may make it difficult to distinguish these lesions from malignant entities, such as urothelial carcinoma and prostatic adenocarcinoma. In this study, we explored whether napsin A, a sensitive marker for lung adenocarcinoma, may also have a role in distinguishing nephrogenic adenoma from other genitourinary lesions. Immunohistochemically, napsin A was expressed in all 43 nephrogenic adenomas (bladder: 38, prostatic urethra: 4, and ureter: 1; mean positive tumor cells: 72%, median: 80%, range: 15-100%) and showed regional variability in its expression pattern with a bias toward surface architectures (flat, papillary) compared with stromal architectures (tubular/glandular, microcystic). We also compared napsin A with other markers including PAX8, GATA3, p63, and 34BE12. Although napsin A matched PAX8 in terms of its sensitivity for nephrogenic adenoma (100%), napsin A stained a lower percentage of tumor cells than PAX8 (72% vs 99%, respectively, P = 1.0 × 10-5). P63 was negative in all nephrogenic adenomas, whereas GATA3 showed variable staining in 25 cases (58%). All 43 nephrogenic adenomas showed variable 34BE12 staining. Finally, we profiled napsin A expression among 401 genitourinary tumors on tissue microarrays (n = 308) and full tissue blocks (N = 93) and observed napsin A positivity in 37 tumors (9%), which included urothelial carcinomas with the glandular/microcystic component differentiation (in the glandular/microcystic component in 4/6), bladder adenocarcinomas (primary: 4/4 and metastatic: 3/3), urinary tract clear-cell carcinomas (primary: 8/9, metastatic uterine primary: 1/1), and some renal tumors (17/174). All 81 pure urothelial carcinomas and 53 prostatic acinar adenocarcinomas were negative for napsin A. Our study indicates that napsin A is a highly sensitive marker for nephrogenic adenoma and can serve as a useful addition in immunohistochemical panels seeking to distinguish it from pure urothelial carcinoma and prostatic acinar adenocarcinoma but not clear-cell carcinoma or urothelial carcinoma with glandular differentiation.

Histological clues to the diagnosis of metastasis to the breast from extramammary malignancies

AIMS

The aims of this study were to review the histological features useful for the identification of metastases to the breast and to investigate the impression that this diagnosis has become more common.

METHODS AND RESULTS

The histological features of metastases to the breast from 2008 to 2018 were reviewed. Seventy-four biopsies from 66 patients were identified: 1% compared with primary carcinoma of the breast. Non-haematological metastases comprised 0.75% compared with 0.3% in a series from 1996 to 2005. The most common tumour types were pulmonary carcinoma (22), lymphoma (15), melanoma (13), gastrointestinal carcinoma (eight) and serous papillary carcinoma (four). In 73% there were histological features that were not typical of primary mammary carcinoma. Some metastases were histologically similar to breast cancer and the history was essential to making the correct diagnosis. Useful histological clues included small-cell morphology for pulmonary carcinoma, glands containing necrosis for gastrointestinal carcinoma, intranuclear inclusions, marked pleomorphism and spindle cells for melanoma, clear cells for renal carcinoma, papillary architecture for serous papillary carcinoma and sheets of centroblasts or nodules of centroblasts and centrocytes for lymphoma. Useful immunohistochemical markers included TTF-1 for pulmonary carcinoma, S100, melan-A and HMB45 for melanoma, CK20 and CDX2 for colorectal carcinoma, PAX8 and WT1 for serous papillary carcinoma and lymphoid markers for lymphomas, in addition to the absence of expression of mammary markers ER, GATA3 and GCDFP-15.

CONCLUSION

The majority of metastases to the breast have histological clues to the diagnosis. Immunohistochemistry is helpful. This diagnosis is being made more frequently.

Combined SOX10 GATA3 is most sensitive in detecting primary and metastatic breast cancers: a comparative study of breast markers in multiple tumors

PURPOSE

For invasive breast cancer (IBC), high SOX10 expression was reported particularly in TNBC. This raised the possibility that SOX10 may complement other breast markers for determining cancers of breast origin.

METHODS

Here, we compared the expression of SOX10 with other breast markers (GATA3, mammaglobin and GCDFP15) and their combined expression in a large cohort of IBC together with nodal metastases. We have also evaluated the expression of GATA3 and SOX10 in a wide spectrum of non-breast carcinomas to assess their value as breast specific markers.

RESULTS

Compared with other markers, SOX10 showed lower overall sensitivity (6.5%), but higher sensitivity in TNBC (31.4%) than other breast markers including GATA3 (29.7% for TNBC). Its expression demonstrated the highest concordance between the paired IBC and nodal metastases (96.4%, κ = 0.663) among all the breast markers. More importantly, SOX10 identified many GATA3-negative TNBC, thus the SOX10/GATA3 combination was the most sensitive marker combination for IBC (86.6%). For non-breast carcinoma, a high SOX10/GATA3 expression rate was found in melanoma (77.9%, predominately expressed SOX10), urothelial carcinoma (82.0%, predominately expressed GATA3) and salivary gland tumors (69.4%). Other carcinomas, including cancers from lungs, showed very low expression for the marker combination.

CONCLUSIONS

The data suggested that SOX10/GATA3 combination can be used for differentiating metastases of breast and multiple non-breast origins. However, the differentiation with melanoma and urothelial tumors required more careful histologic examination, thorough clinical information and additional site-specific IHC markers. For salivary gland tumors, the overlapping tumor types with IBC renders the differentiation difficult.

Pancreatic neuroendocrine tumors with somatostatin expression and paraganglioma-like features

A small fraction of pancreatic neuroendocrine tumors (PanNETs) shows a solid, paraganglioma-like (PG-like) histology. We wanted to know whether these PanNETs have a special hormone expression and are related to paragangliomas (PGs)/pheochromocytomas (PCs). We screened a series of 48 surgically resected PanNETs for their histological growth patterns and their association with expression of islet hormones. The PanNETs were divided into PG-like and non-PG-like tumors and immunohistochemically monitored for the expression of islet hormones, cytokeratins, and S100. The results were correlated to histological pattern, lymph node status, and data in 28 PGs/PCs, including 2 PGs attached to the pancreas. All PanNETs, in contrast to PGs/PCs, were cytokeratin positive. A PG-like growth pattern was identified in 9 of 48 PanNETs and correlated with somatostatin expression. Only half of the non-PG-like PanNETs also contained somatostatin-positive cells. Eight of 28 PGs/PCs expressed somatostatin, mostly in individual cells. PG-like PanNETs and non-PG-like PanNETs infiltrated the adjacent pancreatic tissue, whereas 2 to the pancreas-associated PGs were well demarcated. Lymph node metastases were detected in 58%, 39%, 57%, and 53% of the somatostatin-producing, somatostatin-negative, PG-like, and non-PG-like PanNETs, respectively. PG-like PanNETs, in contrast to PG/PCs, are characterized by the expression of cytokeratin and somatostatin, the development of lymph node metastasis, and the infiltration into pancreatic parenchyma. Non-PG-like PanNETs may also express somatostatin and show lymph node metastases to the same extent. A literature review of cases reported as PG of the pancreas reveals that only a small fraction of these tumors probably represents true pancreatic PGs.