SATB2 in Combination With Cytokeratin 20 Identifies Over 95% of all Colorectal Carcinomas

Expression rate and comparison of immunohistochemistry biomarkers in appendiceal neuroendocrine and other epithelial cell neoplasms: Systematic review and meta-analysis

Background: Immunohistochemistry (IHC) provides comprehensive information for morphology and pathologic characteristics and is a valuable tool for establishing the correct cancer diagnosis in clinical diagnostic pathology and determining prognosis. Objectives: The current study analyzes and compares the expression of Immunohistochemistry biomarkers on neuroendocrine and epithelial cell types of appendiceal neoplasms. Design: This systematic review adhered to the recommendations in the Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) statement. We performed a meta-analysis employing a random effects model with proportions to gauge the proportion of positive cases. Method: A comprehensive systematic search in PubMed, Web of Science, and Scopus databases was conducted based on the PRISMA statement up to August 2023. Studies reporting the immunohistochemistry biomarkers expression performed in patients with primary appendiceal neuroendocrine and epithelial cell neoplasms according to the most recent World Health Organization classification of malignant tumors were included. Results: Our systematic search included 56 observational articles that meet the eligibility criteria. Meta-analysis revealed an expression rate of 93%, 91%, 87%, 71%, 94%, 99%, 32%, 76%, 25%, and 91% for non-specific enolase (NSE), chromaffin A, synaptophysin, Serotonin, SATB2, Caudal-type homeobox 2 (CDX2), β-catenin, Carcinoembryonic antigen (CEA), Cytokeratin 7, and Cytokeratin 20, respectively. CDX2 and SATB2 were the most expressed markers. The expression rate had a significant association with tumor type. NSE and synaptophysin were the highest in neuroendocrine tumors, whereas CEA was more elevated in gablet cell carcinoids. Cytokeratin 20 is suitable for identifying epithelial cell neoplasms. Conclusion: The study indicates the proportion of positive cases in patients with primary neuroendocrine and epithelial cell appendiceal neoplasms.

Reduced Expression of SATB2 in Colorectal Cancer and Its Association with Demographic and Clinicopathological Parameters

Special AT-rich sequence-binding protein 2 (SATB2), as a nuclear matrix-associated protein and transcription factor engaged in chromatin remodeling and the regulation of gene expression, plays an important role in growth and development processes. SATB2 has been shown to have tissue-specific expression, also related to some cancers, including colorectal cancer (CRC). The aim of this study was to compare SATB2 gene expression in tumor and matched non-involved colorectal tissues obtained from CRC patients, and to investigate its association with clinicopathological and demographic parameters, as well as patients' overall survival. SATB2 mRNA levels in the tested tissues were assessed by quantitative polymerase chain reaction, while SATB2 protein expression was determined by immunohistochemistry. We found that the average levels of both SATB2 mRNA and protein were significantly lower in tumor specimens than in matched non-involved colon tissues. Moreover, SATB2 immunoreactivity was associated with patients' sex, tumor localization, and grade of differentiation. Lower immunoreactivity of SATB2 protein was noted in high-grade tumors, in women, and in tumors located in the cecum, ascending, and transverse colon. However, the results of the present study did not show an association between SATB2 expression levels and patients' overall survival. Our findings indicate the involvement of impaired SATB2 expression, significantly reduced in high-grading tumors, in the pathogenesis of CRC, while its sex- and localization-specificity should be further elucidated.

SATB2 expression in oral sarcomatoid (spindle cell) squamous cell carcinoma: clinicopathologic and immunophenotypic characterization of 10 cases

OBJECTIVE

Sarcomatoid squamous cell carcinoma (sSCC) represents an uncommon histopathologic variant of squamous cell carcinoma (SCC). We examined the clinicopathologic and immunophenotypic characteristics, including SATB2 expression, of 10 cases of oral sSCCs.

STUDY DESIGN

Archived sSCC cases diagnosed during the period 2000 to 2023 were retrieved. Lesions lacking proper histomorphological features or adequate immunohistochemical confirmation were excluded. Patient age, sex, and lesion location were recorded. All cases were immunostained against SATB2 (Clone EP281; Cell Marque).

RESULTS

Ten oral sSCCs were identified (M:F ratio = 1.5:1; age range = 47-82 years, median = 74.5 years). The tongue was the most common anatomic site. Lesions presented as fungating or ulcerated, polypoid, and indurated masses. Microscopically, most tumors demonstrated an infiltrative population of atypical spindle cells organized in slender cords or fascicles. Rhabdoid/plasmacytoid morphology was observed in 3 cases. Immunohistochemically, all cases exhibited strong, focal-to-diffuse positivity for pancytokeratin, p63, and/or p40. Patchy, moderate-to-strong SATB2 staining was seen in 4 oral sSCCs, whereas 4 additional cases showed rare, weak-to-moderate expression.

CONCLUSIONS

Oral sSCC is uncommon and primarily exhibits spindled histomorphology, although rhabdoid/plasmacytoid features may be observed. A battery of epithelial and non-epithelial markers is required for proper diagnosis. Positive SATB2 immunostaining in oral sSCCs may pose a potential diagnostic pitfall, particularly in small biopsy specimens. (Oral Surg Oral Med Oral Pathol Oral Radiol YEAR;VOL:page range).

SATB2 is an Emergent Biomarker of Anaplastic Thyroid Carcinoma: A Series with Comprehensive Biomarker and Molecular Studies

Anaplastic thyroid carcinoma (ATC) is a rare and aggressive thyroid malignancy typically comprised of undifferentiated tumor cells with various histologic morphologies, which makes the diagnosis challenging. These tumors commonly show loss of thyroglobulin and TTF1 with preservation of cytokeratin (67%) and Paired Box Gene 8 (PAX8) (55%) expression. Identification of a sensitive immunohistochemical stain to aid in the diagnosis of ATC would be beneficial. Immunohistochemistry (IHC) against special AT-rich sequence-binding protein 2 (SATB2) protein is a sensitive and specific marker expressed in colorectal adenocarcinoma and bone or soft tissue tumors with osteoblastic differentiation. However, SATB2 is also expressed in other sarcomatous/undifferentiated neoplasms lacking osteoblastic differentiation. Using quantitative reverse transcription PCR (RT-qPCR) we showed that there is variable expression of SATB2 mRNA expression in ATCs. To evaluate the role of SATB2 protein expression in ATC, we performed PAX8, SATB2, pancytokeratin (AE1/AE3 & CAM5.2), claudin-4 and TTF1 immunostaining on 23 cases. ATCs showed retained expression of PAX8 in 65% (15/23); SATB2 was detected in 74% (17/23); pancytokeratin was expressed in 65% (15/23); claudin-4 was expressed in 35% (8/23) and TTF1 showed expression in 13% (3/23) of cases. Furthermore, 83% (5/6) of ATCs which lacked SATB2 expression, retained PAX8 expression, while 88% (7/8) of the tumors without PAX8 expression were positive for SATB2. Differentiated follicular cell-derived thyroid cancers (n = 30), differentiated high grade thyroid carcinoma (n = 3), and poorly differentiated thyroid carcinoma (n = 8) were negative for SATB2 immunoreactivity. Next-generation selected cases detected the commonly identified oncogenic variants including those in BRAF, RAS, TP53, and TERT promoter. Overall, we hereby demonstrate that SATB2 IHC may be used to support the diagnosis of ATC.

Primary medullary adenocarcinoma of the colon: Literature review and case series

Aims

Medullary carcinoma of the colon is a rare subtype of adenocarcinoma, first described in 1999. Clinically known to have a favourable prognosis in comparison to poorly differentiated cancers, it is associated with deficient mismatch repair. This is an observational single center study of patients with medullary cancer, and comparison with the current literature.

Methods

We performed a search of the pathological database at our institution for medullary adenocarcinomas between the years of 2016-2023 and reviewed their clinical information to collect all relevant data including patient history, hospital admissions. surgery and clinic visits. We then performed a literature search using Pubmed for search terms medullary cancer/carcinoma of the colon/colorectum.

Results

11 patients were found in our database, 34 studies in the literature, 19 retrospective cohort studies (3144 patients) and 13 case reports. 81.8% (vs. 73.22% in cohort studies) were female patients. 8/11 patients' tumours had lympho-vascular invasion with 2/11 perineural involvement. Immunohistochemistry demonstrated 11/11 patients' tumours with MLH1 and PMS2 loss, and presence of MSH2 and MSH6. Cohort studies demonstrated 302/1897 (15.92%) tumours had perineural invasion with 1133/2151 (52.67%) demonstrating lympho-vascular invasion. MLH1 testing was available for 192 patients, with 93.75% having loss of MLH1.

Conclusion

Our cohort of medullary cancer patients were similar to that in the literature, with regards to demographics, staging and tumour characteristics. A longer follow-up time is required for our cohort to analyze long term survival outcomes.

Special AT-rich sequence-binding protein 2 immunohistochemistry in the diagnosis of osteosarcoma in dogs

Malignant osteoblasts can have markedly pleomorphic phenotypes and variable amounts of tumour-associated matrix, complicating the ability of pathologists to accurately differentiate osteosarcoma (OSA) from other types of neoplasms using only histopathology. Current immunohistochemical markers for animals have limited sensitivity and specificity in identifying OSA or produce inconsistent results. Immunohistochemistry (IHC) for special AT-rich sequence-binding protein 2 (SATB2) has been used in human medicine to aid in identification of normal and neoplastic osteoblasts, and the objective of this study was to determine whether this marker could also be useful for the diagnosis of canine OSA. Initially, SATB2 IHC was performed on eight samples from cases of well-differentiated canine OSA and on other tumour types for which OSA is a differential diagnosis, as well as on normal tissues, to assess sensitivity and cross-reactivity. Following confirmation that SATB2 is immunoreactive for normal and neoplastic canine osteoblasts and negative in other non-osseous mesenchymal cell types and organs, SATB2 IHC was tested on 123 cases of poorly differentiated malignant neoplasms as part of a panel with other immunohistochemical markers, as appropriate, based on histomorphology and differential diagnoses. The conclusion is that SATB2 IHC is a sensitive and specific marker for identifying canine OSA when used in a panel with other immunohistochemical markers and in conjunction with supportive clinical history.

Role of Immunohistochemistry in the Diagnosis of Pilomatrical Tumors

Pilomatrical skin tumors harbor mutations in CTNNB1, which encodes for β-catenin, a downstream effector of the Wnt signaling pathway responsible for the differentiation, proliferation, and adhesion of epithelial stem cells. Therefore, downstream molecules, such as CDX2, LEF-1, and SATB2, in the Wnt signaling pathway could be useful diagnostic markers. Here, we sought to investigate the potential of immunohistochemistry (IHC) to differentiate between pilomatricoma and pilomatrical carcinoma, as well as from other cutaneous adnexal tumors. We studied 88 cases of cutaneous tumors (14 pilomatrical carcinomas, 18 pilomatricomas, 13 basal cell carcinomas, 12 squamous cell carcinomas, 12 sebaceous carcinomas, 10 Merkel cell carcinomas, 7 trichoblastomas, and 2 hidradenocarcinomas) using a broad panel of IHC markers: β-catenin, SATB2, CDX2, LEF1, Ber-EP4, and PRAME. Pilomatricoma and pilomatrical carcinoma displayed >75% nuclear staining for β-catenin. CDX2 also strongly stained pilomatrical tumors; however, the staining distribution was limited in pilomatricoma and more widespread in pilomatrical carcinoma. But, overall, it was less than β-catenin. SATB2 and Ber-EP4 expressions were noted only in a subset of both pilomatrical carcinoma and pilomatricoma, whereas LEF-1 showed strong, diffuse nuclear positivity in both pilomatricoma and pilomatrical carcinoma. Among the IHC markers evaluated, none could distinguish between pilomatricoma and pilomatrical carcinoma. However, the combined use of β-catenin with CDX2 markers may assist in not only confirming the pilomatrical nature of the proliferation but also in differentiating benign from malignant cases when there is a significant presence of CDX2 staining. Despite these findings, the diagnosis should continue to primarily depend on a thorough histopathologic examination.

Immunohistochemical expression of SATB2 and PAX8 in differentiating primary from metastatic ovarian mucinous neoplasms

Accurate stratification of an ovarian mucinous neoplasm as primary or secondary is always challenging as they show overlapping histomorphological and immunohistochemical features. Immunohistochemical staining for SATB2 and PAX8 was performed on 80 cases of mucinous ovarian neoplasms subdivided into 53 primary [25 primary ovarian mucinous carcinomas (POMCs) and 28 mucinous borderline tumors (MBTs)] and 27 secondary (12 of colonic origin, 7 of appendiceal origin, and 8 of gastric origin). Expression was correlated with different clinicopathologic parameters. PAX8-positive immunostaining was detected in 38 out of 53 cases (71.69%) of primary ovarian mucinous neoplasms (POMNs) with null positivity in the secondary ovarian mucinous tumors (0/27). SATB2-positive expression was detected in 16 out of 27 cases (59.26%) of the secondary ovarian mucinous tumors. None of the studied POMNs showed any positive immunostaining for SATB2 (0/53). A profile of SATB2-/PAX8+ and SATB2+/PAX8- can be used to differentiate POMNCs from secondary ovarian mucinous tumors of GI origin, respectively, with 100% specificity. PAX8 expression is associated with some clinicopathologic parameters providing the basis for the possible usage of PAX8 as prognostic marker.

The utility of the lineage specific immunohistochemical stains SATB2, CDX2, and villin, and the mucin glycoproteins MUC2, MUC5AC, and MUC6 to distinguish pulmonary invasive mucinous adenocarcinoma from metastatic colorectal carcinoma

CONTEXT

The lungs are a common site of tumor metastasis. While morphology and immunophenotype can help differentiate primary from metastatic tumors, distinguishing pulmonary invasive mucinous adenocarcinoma (PIMA) from metastatic colorectal adenocarcinoma (CRC) may occasionally be challenging due to overlapping morphological and immunohistochemical features. Lineage-specific markers such as CDX2, TTF-1, and napsin A are helpful with pulmonary non-mucinous adenocarcinoma (PNMA), however they are non-specific and insensitive when applied to PIMA. SATB2 is a newer marker that distinguishes CRC from upper gastrointestinal and pancreaticobiliary tumors; its utility in distinguishing CRC from PIMA has not been fully elucidated.

OBJECTIVE

To evaluate the performance of lineage-specific and mucin glycoprotein immunostains in distinguishing PIMA and CRC.

DESIGN

We stained tissue microarrays comprising 34 PNMA, 31 PIMA, and 32 CRC with CK7, CK20, SATB2, CDX2, villin, TTF-1, napsin A, and gel-forming mucins MUC2, MUC5AC, and MUC6.

RESULTS

PIMA showed significant (>50% of cells) expression of SATB2 (6%), CDX2 (6%), villin (74%), TTF-1 (13%), and napsin A (23%). However, significant CK7 expression was seen in nearly all PIMA (30/31) and none of the metastatic CRC.

CONCLUSION

Our results suggest that CK7 remains one of the most useful markers for distinguishing primary PIMA from metastatic CRC. Expression of the mucin glycoproteins MUC5AC and MUC6 and lack of expression of MUC2 favored a diagnosis of PIMA, but expression of these markers was too heterogeneous to be of clinical utility. To our knowledge this is the only study comparing the immunohistochemical profile of PIMA and metastatic CRC in lung metastasectomy specimens.

Utility of SATB2 and MOC-31 Immunostains to Distinguish Between Poorly Differentiated Rectal Adenocarcinoma and Anal Squamous Cell Carcinoma

OBJECTIVES

Colorectal adenocarcinoma and squamous cell carcinoma (SCC) can arise in the anorectum and present a significant diagnostic challenge when poorly differentiated. Accurate diagnosis can significantly influence management, as the treatments for these conditions involve distinct neoadjuvant chemoradiotherapy regimens. MOC-31 and SATB2 have been utilized as specific markers of glandular differentiation and colorectal origin, respectively, but studies have shown that they may be positive in squamous cell carcinoma of other sites. This raises the concern that MOC-31 and SATB2 may be positive in squamous cell carcinoma of the anorectum, and overreliance on these stains may be a potential diagnostic pitfall in differentiating rectal poorly differentiated adenocarcinoma (PDA) from anal nonkeratinizing SCC.

METHODS

We identified biopsies from 10 rectal PDA and 17 anorectal nonkeratinizing SCC cases and stained them for MOC-31 and SATB2.

RESULTS

We found that MOC-31 was highly sensitive, being positive in 10/10 cases of rectal PDA, but not specific, as it was also positive in 11/17 SCC cases. In contrast, SATB2 was both sensitive, with positive staining in 10/10 rectal PDA cases, and specific, with negative staining in 17/17 SCC cases. This includes equivocal staining in 4 of these negative SCC cases. MOC-31 had a sensitivity of 100% and specificity of 35.3%, while SATB2 had a sensitivity of 100% and specificity of 100%.

CONCLUSIONS

Unlike squamous mucosa of the head and neck, and esophagus, SCC of the anus does not frequently stain positively for SATB2. These data suggest that SATB2 is a reliable marker in distinguishing rectal PDA from anorectal nonkeratinizing SCC, whereas MOC-31 is commonly positive in SCC of the anus. It is also important to note that equivocal SATB2 staining may be seen in SCC.

Use of SATB2 and CDX2 Immunohistochemistry to Characterize and Diagnose Colorectal Cancer

SATB2 has been reported to be highly specific for lower gastrointestinal tract tumors. On the basis of its ileum-colon conversion effects, which involve the activation of colonic genes in cooperation with CDX2 and HNF4A, we hypothesized that SATB2 and CDX2 might define the characteristics of colorectal cancers (CRCs). In the present study, the clinicopathologic and immunohistochemical characteristics of 269 CRCs were analyzed according to SATB2 and CDX2 expression. CRCs with SATB2- and/or CDX2- phenotypes showed associations with poorly differentiated histotypes ( P <0.00001), mucus production ( P =0.0019), and mismatch repair-deficient phenotypes ( P <0.00001). SATB2-/CDX2- CRCs were significantly associated with CK20-negativity, with or without CK7 expression ( P <0.00001), as well as with MUC5AC-positivity ( P <0.00001), and CD10-negativity ( P =0.00047). Negativity for SATB2 or CDX2 was associated with the expression of PD-L1 in both all CRC ( P <0.00001) and mismatch repair-proficient CRC ( P =0.000091). Multivariate Cox hazard regression analysis identified negativity for SATB2 and/or CDX2 as potential independent risk factors for patients with CRC. Regarding the diagnostic utility of SATB2, all of the 44 CRC metastases could be diagnosed as colorectal in origin if the immunohistochemical phenotypes (including CK7, CK20, and p53) of the primary lesions and patient history were considered. Among the other 684 tumors, we were unable to distinguish a case of CK7-/CK20+/CDX2+/SATB2+ ovarian mucinous cystadenocarcinoma from metastatic CRC without the patient history and clinical information.

Diagnostic gastrointestinal markers in primary lung cancer and pulmonary metastases

Histopathological diagnosis of pulmonary tumors is essential for treatment decisions. The distinction between primary lung adenocarcinoma and pulmonary metastasis from the gastrointestinal (GI) tract may be difficult. Therefore, we compared the diagnostic value of several immunohistochemical markers in pulmonary tumors. Tissue microarrays from 629 resected primary lung cancers and 422 resected pulmonary epithelial metastases from various sites (whereof 275 colorectal cancer) were investigated for the immunohistochemical expression of CDH17, GPA33, MUC2, MUC6, SATB2, and SMAD4, for comparison with CDX2, CK20, CK7, and TTF-1. The most sensitive markers for GI origin were GPA33 (positive in 98%, 60%, and 100% of pulmonary metastases from colorectal cancer, pancreatic cancer, and other GI adenocarcinomas, respectively), CDX2 (99/40/100%), and CDH17 (99/0/100%). In comparison, SATB2 and CK20 showed higher specificity, with expression in 5% and 10% of mucinous primary lung adenocarcinomas and both in 0% of TTF-1-negative non-mucinous primary lung adenocarcinomas (25-50% and 5-16%, respectively, for GPA33/CDX2/CDH17). MUC2 was negative in all primary lung cancers, but positive only in less than half of pulmonary metastases from mucinous adenocarcinomas from other organs. Combining six GI markers did not perfectly separate primary lung cancers from pulmonary metastases including subgroups such as mucinous adenocarcinomas or CK7-positive GI tract metastases. This comprehensive comparison suggests that CDH17, GPA33, and SATB2 may be used as equivalent alternatives to CDX2 and CK20. However, no single or combination of markers can categorically distinguish primary lung cancers from metastatic GI tract cancer.

Concomitant expression patterns of CDX2 and SATB2 as prognostic factors in stage III colorectal cancers

CDX2 and SATB2 are often used as biomarkers for identification of colorectal origin in primary or metastatic adenocarcinomas. Loss of CDX2 or SATB2 expression has been associated with poor prognosis in patients with colorectal cancer (CRC). However, little is known regarding clinicopathological features, including prognosis, of CRCs with concomitant loss of CDX2 and SATB2. A total of 431 stage III CRCs were analyzed for their expression status in CDX2 and SATB2 using tissue microarray-based immunohistochemistry and expression status was correlated with clinicopathological variables, molecular alterations, and survival. CDX2-negative (CDX2-) CRCs and SATB2-negative (SATB2-) CRCs were found in 8.1 % and 17.2 % of CRCs, respectively, whereas both CDX2-negative and SATB2-negative (CDX2-/SATB2-) CRCs comprised 3.2 % of the CRCs. On survival analysis, neither CDX2-/SATB2+ nor CDX2+/SABT2- CRCs but CDX2-/SATB2- CRCs were associated with poor prognosis. CDX2-/SATB2- CRCs showed significant associations with tumor subsite of right colon, poor differentiation, decreased expression of CK20, aberrant expression of CK7, CIMP-high, MSI-high, and BRAF mutation. In summary, our results suggest that concomitant loss of CDX2 and SATB2 is a prognostic biomarker but isolated loss of CDX2 or SATB2 is not a prognostic biomarker for stage III CRCs.

Meta-analysis of SATB2 immunohistochemical expression in colorectal cancer versus primary ovarian mucinous neoplasms

BACKGROUND

Reliably distinguishing primary ovarian mucinous neoplasms (POMNs) from metastatic colorectal cancers (CRCs) is both challenging to the histopathologist and of great clinical importance. Special AT-rich sequence binding protein-2 (SATB2) has emerged as a useful diagnostic immunohistochemical marker of colorectal cancer. This meta-analysis compares SATB2 expression in POMNs and CRC.

METHODS

A systematic literature search for relevant studies was conducted. Meta-analysis of SATB2 positivity was undertaken using a random effects model.

RESULTS

Seven studies including 711 CRCs and 528 POMNs were included. SATB2 positivity was seen in 81 % (95 % CI: 72-88 %) of CRCs and 4 % (95 % CI: 1-11 %) of POMNs. Variation was seen in immunohistochemical methods used for SATB2 detection and threshold for positivity.

CONCLUSION

SATB2 staining remains high in CRC and low in POMNs, supporting its use in differentiating these two pathologies with vastly differing prognosis and treatment.

Multimodal diagnostic strategies and precision medicine in mucinous ovarian carcinoma: a comprehensive approach

Mucinous ovarian carcinoma (MOC) represents a distinct entity within ovarian malignancies, characterized by diagnostic challenges due to its rarity and the potential overlap with other tumor types. The determination of tumor origin is important for precise postsurgical treatment. This article highlights the accurate diagnosis and management of MOC, including the use of imaging modalities, serological tumor markers, immunohistochemistry, and genomic analyses. Transabdominal and transvaginal ultrasonography, complemented by MRI and CT, plays a pivotal role in differentiating MOC from other mucinous tumors and in surgical planning, particularly for fertility preservation. Serological markers like CA19-9, CA-125, and CEA, though not definitive, provide valuable preoperative insights. Immunohistochemistry aids in distinguishing primary MOC from metastatic mucinous carcinomas, while genomic profiling offers the potential for precision medicine through the identification of specific molecular signatures and treatment susceptibilities. Despite advancements in diagnostic techniques, no single method conclusively differentiates between primary and metastatic tumors intraoperatively. The paper reviews the origins, diagnosis, and differential diagnosis of primary mucinous ovarian carcinoma highlights the need for a multimodal diagnostic approach and advocates for the inclusion of MOC patients in clinical trials for personalized therapies, recognizing the heterogeneity of the disease at the molecular level.

SATB2 Cytoplasmic Expression is Characteristic of a Subset of Ovarian Stromal Cells and Sex Cord Stromal Tumors

Special AT-rich sequence-binding protein 2 (SATB2) is a nuclear transcription factor that shows consistent nuclear staining in colorectal adenocarcinoma and osteosarcoma. Following the observation of cytoplasmic staining with this marker in luteinized ovarian stromal cells, we studied the expression of SATB2 in ovarian stromal cells, various types of follicular cysts, and sex cord-stromal tumors. Eighty-five cases were stained for SATB2. Ovarian hilar Leydig cells (n = 12), luteinized stromal cells (n = 10), corpora lutea (n = 4), luteinized follicular cysts (n = 4), and stromal hyperthecosis (n = 6) exhibited consistent, usually diffuse, granular cytoplasmic staining. In addition, Leydig cell tumors (n = 1) and steroid cell tumors (n = 4) showed diffuse cytoplasmic staining. SATB2 also exhibited cytoplasmic staining in most Sertoli-Leydig cell tumors (n = 16) and gynandroblastomas (n = 3) confined to the Leydig cell component. Adult granulosa cell tumors (n = 14), juvenile granulosa cell tumors (n = 3), sex cord tumors with annular tubules (n = 3), cellular fibromas (n = 3), sclerosing stromal tumors (n = 1), and thecomas (n = 1) were negative apart from cytoplasmic staining in associated luteinized stromal cells. SATB2 cytoplasmic staining has not been previously described in these lesions but is characteristic of a variety of ovarian stromal cells and sex cord-stromal tumors, in particular, those exhibiting luteinization or a Leydig or steroid cell component. SATB2 staining may be of value in identifying luteinized or Leydig cells when these are morphologically inconspicuous.

Oncogenic Role of SATB2 In Vitro: Regulator of Pluripotency, Self-Renewal, and Epithelial-Mesenchymal Transition in Prostate Cancer

Special AT-rich sequence binding protein-2 (SATB2) is a nuclear matrix protein that binds to nuclear attachment regions and is involved in chromatin remodeling and transcription regulation. In stem cells, it regulates the expression of genes required for maintaining pluripotency and self-renewal and epithelial-mesenchymal transition (EMT). In this study, we examined the oncogenic role of SATB2 in prostate cancer and assessed whether overexpression of SATB2 in human normal prostate epithelial cells (PrECs) induces properties of cancer stem cells (CSCs). The results demonstrate that SATB2 is highly expressed in prostate cancer cell lines and CSCs, but not in PrECs. Overexpression of SATB2 in PrECs induces cellular transformation which was evident by the formation of colonies in soft agar and spheroids in suspension. Overexpression of SATB2 in PrECs also resulted in induction of stem cell markers (CD44 and CD133), pluripotency-maintaining transcription factors (cMYC, OCT4, SOX2, KLF4, and NANOG), CADHERIN switch, and EMT-related transcription factors. Chromatin immunoprecipitation assay demonstrated that SATB2 can directly bind to promoters of BCL-2, BSP, NANOG, MYC, XIAP, KLF4, and HOXA2, suggesting SATB2 is capable of directly regulating pluripotency/self-renewal, cell survival, and proliferation. Since prostate CSCs play a crucial role in cancer initiation, progression, and metastasis, we also examined the effects of SATB2 knockdown on stemness. SATB2 knockdown in prostate CSCs inhibited spheroid formation, cell viability, colony formation, cell motility, migration, and invasion compared to their scrambled control groups. SATB2 knockdown in CSCs also upregulated the expression of E-CADHERIN and inhibited the expression of N-CADHERIN, SNAIL, SLUG, and ZEB1. The expression of SATB2 was significantly higher in prostate adenocarcinoma compared to normal tissues. Overall, our data suggest that SATB2 acts as an oncogenic factor where it is capable of inducing malignant changes in PrECs by inducing CSC characteristics.

Loss of SATB2 and CDX2 expression is associated with DNA mismatch repair protein deficiency and BRAF mutation in colorectal cancer

The relationship between the expression of the SATB2 and CDX2 proteins and common molecular changes and clinical prognosis in colorectal cancer (CRC) still needs further clarification. We collected 1180 cases of CRC and explored the association between the expression of SATB2 and CDX2 and clinicopathological characteristics, molecular alterations, and overall survival of CRC using whole-slide immunohistochemistry. Our results showed that negative expression of SATB2 and CDX2 was more common in MMR-protein-deficient CRC than in MMR-protein-proficient CRC (15.8% vs. 6.0%, P = 0.001; 14.5% vs. 4.0%, P = 0.000, respectively). Negative expression of SATB2 and CDX2 was more common in BRAF-mutant CRC than in BRAF wild-type CRC (17.2% vs. 6.1%, P = 0.003; 13.8% vs. 4. 2%; P = 0.004, respectively). There was no relationship between SATB2 and/or CDX2 negative expression and KRAS, NRAS, and PIK3CA mutations. The lack of expression of SATB2 and CDX2 was associated with poor histopathological features of CRC. In multivariate analysis, negative expression of SATB2 (P = 0.030), negative expression of CDX2 (P = 0.043) and late clinical stage (P = 0.000) were associated with decreased overall survival of CRC. In conclusion, the lack of SATB2 and CDX2 expression in CRC was associated with MMR protein deficiency and BRAF mutation, but not with KRAS, NRAS and PIK3CA mutation. SATB2 and CDX2 are prognostic biomarkers in patients with CRC.

Divergent Lineage Markers in Anaplastic Thyroid Carcinoma

Anaplastic thyroid carcinoma (ATC) often results from dedifferentiation of differentiated thyroid carcinoma (DTC), and the diagnosis is not difficult, as the tumor is seen to progress from a recognized DTC. However, in some cases, the diagnosis based on biopsy of limited tissue or resection of a completely undifferentiated tumor relies on immunohistochemical biomarkers and is usually a diagnosis of exclusion. To examine the biomarker profile of ATC and to determine whether divergent lineage markers can complicate this process, we examined the expression of a number of biomarkers in a series of ATCs. Cases retrieved from the department laboratory information system were included if there was evidence of an accurate diagnosis based on the presence of a coexisting or antecedent DTC or in cases where the immunoprofile was consistent with thyroid origin in a non-equivocal clinical setting. Questionable cases were excluded. We identified 36 cases for analysis. Tissue sections were stained for PAX8, TTF1, BRAFV600E, NRASQ61R, TRK, and p53, as well as p40, CDX2, SATB2, GATA3, CD117, CD163, SALL4, SMARCA4, PRAME, SOX10, ERG and HEPPAR1. As expected, all 36 ATCs were negative for TTF1 except for one showing focal, weak expression. Thirteen expressed PAX8 with variable intensity. BRAFV600E was positive in 10/34 tumors and equivocal in 3; NRASQ61R was positive in 12, and TRK was positive in 1 case. Staining for p53 was diffusely positive in 14 and completely negative in 19, with only 3 cases showing a wild-type pattern. We found aberrant expression of GATA3 in 11/36 cases, SATB2 in 8/36, CD117 in 2/35, and SALL4 in 1/30. CD163 expression was identified in tumor cells in 10/30 cases with variable intensity; in the other tumors, interpretation was obscured by abundant histiocytes. P40 was positive in 5 cases with squamoid morphology. CDX2 was negative in 35 tested cases. PRAME was identified in 1 of 33 cases. Stains for SOX10, ERG, and HEPPAR1 were negative in 33 cases. Twenty tested cases showed retained SMARCA4 expression. We conclude that ATCs express a number of divergent lineage markers that can cause diagnostic dilemmas, as they are also features of other tumors in the differential diagnosis of high-grade midline neck malignancies.

Evaluation of Lineage/Site-specific Nuclear Immunohistochemical Markers SATB2, Cyclin D1, SALL4, and BCOR in High-grade Endometrial Carcinomas

Poorly differentiated malignant neoplasms involving the gynecologic tract routinely include a poorly differentiated endometrial carcinoma (EC) in the differential diagnosis. Some nuclear lineage/site-specific immunohistochemical markers are utilized in this diagnostic setting including SATB2, cyclin D1, SALL4, and BCOR, but their specificity and use in small samples are not clear across the spectrum of ECs. Cases of undifferentiated/dedifferentiated endometrial carcinomas (UEC/DDEC), clear cell carcinoma (CCC), uterine serous carcinoma (USC), FIGO grade 3 endometrial endometrioid carcinoma (EEC), and uterine carcinosarcoma (UCS) were identified and diagnoses confirmed. Whole-section immunohistochemical stains for SATB2, cyclin D1, SALL4, BCOR, and PAX8 were performed. A total of 113 cases were utilized: 15 CCC, 26 EEC, 19 UCS, 22 USC, and 31 UEC/DDEC. Cases were distributed across both low (49%) and high (51%) FIGO clinical stages. SATB2 was expressed by UCS (8/19, 42%), EEC (10/26, 38%), UEC/DDEC (11/30, 37%), and USC (6/22, 27%). Cyclin D1 was expressed by EEC (24/26, 92%), USC (17/22, 77%), UEC/DDEC (15/20 EEC component, 75%; 22/30 UEC, 73%), UCS (10/16 carcinoma, 63%; 11/19 sarcoma, 58%), and CCC (8/15, 53%). SALL4 was expressed most frequently by UEC/DDEC (12/30, 40%), but also USC (7/22, 32%), EEC (5/26, 19%), and UCS (4/16 carcinoma, 25%; 3/19 sarcoma, 16%). BCOR was expressed at low levels in 2 USC, 2 UEC/DDEC, and 2 UCS. PAX8 was generally positive but showed lower expression in UEC/DDEC (17/30, 57%) and in the sarcomatous portions of UCS (6/19, 32%). SATB2, cyclin D1, SALL4, and BCOR stain variable numbers of poorly-differentiated EC and must be carefully interpreted within morphologic and clinical context.

Histopathological Evaluation and Molecular Diagnostic Tests for Peritoneal Metastases with Unknown Primary Site-a Review

Cancer of unknown primary (CUP) is a well-studied entity with guidelines available for the management of patients with CUP. The peritoneum represents one of the metastatic sites in CUP, and peritoneal metastases (PM) could present as CUP. PM of unknown origin remains a poorly studied clinical entity. There is only one series of 15 cases, one population-based study, and few other case reports on this subject. Studies on CUP, in general, cover some common tumour histological types like adenocarcinomas and squamous carcinomas. Some of these tumours may have a good prognosis though majority have high-grade disease with a poor long-term outcome. Some of the histological tumour types commonly seen in the clinical scenario of PM like mucinous carcinoma have not been studied. In this review, we divide PM into five histological types-adenocarcinomas, serous carcinomas, mucinous carcinomas, sarcomas and other rare varieties. We provide algorithms to identify the primary tumour site using immunohistochemistry when imaging, and endoscopy fails to establish the primary tumour site. The role of molecular diagnostic tests for PM or unknown origin is also discussed. Current literature on site-specific systemic therapy based on gene expression profiling does not show a clear benefit of this approach over empirical systemic therapies.

Increased GS-II lectin binding and SATB2 downregulation are biological features for sessile serrated lesions and microvesicular hyperplastic polyps

Sessile serrated lesions (SSLs) and microvesicular hyperplastic polyps (MVHPs) are colorectal lesions displaying gastric differentiation. Griffonia simplicifolia-II (GS-II) is a lectin specific to terminal α/βGlcNAc residues. Here, we assessed GS-II binding and performed immunostaining for HIK1083 (specific to terminal αGlcNAc residues), MUC5AC, MUC6, and special AT-rich sequence binding protein 2 (SATB2) in SSLs, MVHPs, and tubular adenomas (TAs). We observed MUC5AC positivity in 28 of 30 SSLs, but in only three of 23 TAs. Moreover, 24 of 30 SSLs were MUC6-positive, while none of the 23 TAs were MUC6-positive. None of the 30 SSLs or 23 TAs showed HIK1083 positivity. All 30 SSLs and 26 MVHPs were GS-II-positive, while only seven of 23 were in TAs. GS-II staining was mainly distributed in the Golgi region, but SSLs and MVHPs showed goblet cell distribution, in 20 of 30 and 19 of 26 cases, respectively. All SSLs, MVHPs, and TAs were SATB2-positive, but 21 of 30 SSLs and 12 of 26 MVHPs showed decreased staining intensity relative to adjacent mucosa, a decrease seen in only two of 23 in TAs. These results indicate overall that increased terminal βGlcNAc and decreased SATB2 expression are characteristics of SSLs and MVHPs.

microRNA-660 Enhances Cisplatin Sensitivity via Decreasing SATB2 Expression in Lung Adenocarcinoma

Increasing evidence suggests that microRNAs' (miRNAs) abnormal expression is one of the main factors of chemotherapy resistance in various cancers. However, the role of miRNAs in lung adenocarcinoma (LUAD) resistance to cisplatin is still unclear. In this study, we analyzed a microarray dataset to investigate miRNAs related to cisplatin resistance in LUAD. The expression of miRNAs in LUAD tissues and cell lines was detected using real-time quantitative polymerase chain reaction (RT-qPCR). Special AT-Rich Sequence-Binding Protein 2 (SATB2) in LUAD cell lines was detected using RT-qPCR and Western blot. Cell proliferation was measured by CCK8 and colony formation assays, while cell cycle and apoptosis were measured by flow cytometry. A dual-luciferase reporter assay was performed to confirm that SATB2 is a target gene of microRNA-660 (miR-660). We showed that the expression of miR-660 was not only decreased in LUAD cells and tissues but also further decreased in the cisplatin-resistant A549 cell line. The overexpression of miR-660 increased cisplatin sensitivity in LUAD cells. In addition, we identified SATB2 as a direct target gene of miR-660. We also revealed that miR-660 increased cisplatin sensitivity in LUAD cells via targeting SATB2. In conclusion, miR-660/SATB2 axis is a key regulator of cisplatin resistance in LUAD.

Expression of SATB2 in primary cutaneous sarcomatoid neoplasms: a potential diagnostic pitfall

SATB2 can be used as an immunohistochemical marker for osteoblastic differentiation. The differential diagnosis of a cutaneous sarcomatoid neoplasm sometimes includes osteosarcoma when the tumour concomitantly involves the skin, soft tissue, and bone, or when there is a past medical history of osteosarcoma. As the utility of SATB2 immunohistochemistry in these scenarios was unclear, we aimed to determine the frequency and the pattern of SATB2 expression in a variety of cutaneous sarcomatoid neoplasms. SATB2 expression by immunohistochemistry was evaluated by intensity (0-3) and extent (0-100%) of staining to generate an h-score for each case. Expression levels were classified into high-positive (h-score ≥100), low-positive (20-99), and negative (<20) groups. Positive SATB2 expression was observed in 18/23 (78%) atypical fibroxanthomas (AFX), 10/19 (53%) pleomorphic dermal sarcomas, 9/20 (45%) cutaneous sarcomatoid squamous cell carcinomas, 14/39 (36%) sarcomatoid melanomas, 2/13 (15%) poorly differentiated cutaneous angiosarcomas, 10/17 (59%) high-grade cutaneous leiomyosarcomas, and 7/8 (88%) osteosarcoma controls. With the exception of AFX, all cutaneous neoplasms showed significantly lower average h-scores than osteosarcoma. AFX gave the highest average h-score (71) and percentage of high-positive cases (48%) among all examined cutaneous neoplasms. Only two (1.5%) of all cutaneous cases showed strong intensity of staining. Common SATB2 expression in various cutaneous sarcomatoid neoplasms poses a potential diagnostic pitfall when the differential diagnosis includes osteosarcoma. Requirement of strong staining and a high-positive h-score improves the specificity of SATB2 in differentiating these tumours from osteosarcoma.

SATB2 as a Marker of the Proximal Nephron: Expression in Nephrogenic Adenoma and Correlation With Other Renal Tubular Markers

Nephrogenic adenoma (NA) is an infrequent reactive urothelial lesion. The expression of immunohistochemical renal tubular markers has been reported in NA, although a proximal or distal nephron phenotype has not been established. Special AT-rich sequence-binding protein 2 (SATB2) is a marker of a colorectal origin of adenocarcinomas, occasionally reported in renal samples. We have analyzed SATB2 expression in NA, with correlation with other tubular markers, as well as in the normal kidney. Fifty cases of NA were immunostained with PAX8, SATB2, proximal nephron markers [CD10, renal cell carcinoma (RCC) marker, alpha-methylacyl-CoA racemase (AMACR), and CD15], and distal markers (Ksp cadherin, cytokeratin 7, E-cadherin (E-cad), and cytokeratin 19). Ten normal kidney sections were stained with a double method combining SATB2 plus CD10, RCC marker, AMACR, Ksp cadherin, cytokeratin 7, or E-cad. All NA were immunoreactive for PAX8 and 57% for SATB2. Every case was positive for proximal and distal nephron markers: 100% for cytokeratins 7 and 19, 84.1% E-cad +, 81.6% AMACR +, 68.9% Ksp cadherin +, 63% CD15 +, 53.3% CD10 +, and 28.6 % RCC +. In the normal kidney, SATB2 was detected in the straight part of the proximal tubules and the thin descending loops of Henle. NA shows a multiphenotypic pattern with coexpression of both proximal and distal nephron markers, and constant expression of PAX8, cytokeratins 7 and 19. SATB2 is often positive in NA, which should be kept in mind to avoid a possible misdiagnosis of intestinal adenocarcinoma. SATB2 is a marker of the normal proximal nephron.

Impact of Neoadjuvant Chemotherapy on SATB2 Expression in Colorectal Carcinomas: SATB2 Positivity is Preserved in Most Cases, but Down-Expressed in Effective Cases of Chemotherapy

Special AT-rich sequence-binding protein 2 (SATB2) is a novel, diagnostically useful, and highly sensitive immunohistochemical marker for both primary and metastatic colorectal or appendiceal tumors. In the present study, we aimed to assess the impact of neoadjuvant chemotherapy on SATB2 expression in primary colorectal carcinomas and their corresponding liver metastases. Forty-four patients with colorectal carcinomas who received neoadjuvant chemotherapy were included. SATB2 expression in specimens of biopsy, resected primary colorectal carcinomas, and resected metastatic foci were examined by immunohistochemistry and compared to caudal-type homeobox transcription factor 2 (CDX2). Using a modified H-score, expressions were scored semiquantitatively for both staining intensity and tumor cell proportion with nuclear staining. SATB2 was positive in 43/44 cases (98%) in biopsy specimens, 42/44 cases (96%) in resected colorectal carcinomas with neoadjuvant chemotherapy, and 9/9 cases (100%) with liver metastases. However, these expressions were variably decreased, and the H-score was lower in resected colorectal carcinomas (158 ± 69) than in biopsy specimens (174 ± 60) (p < 0.01). The proportion of SATB2-positive area of colorectal carcinoma was 93% in metastatic foci, while the CDX2-positive area was 78%. When categorized by histopathological tumor regression, the most effective tumors of chemotherapy showed the lowest H-score in resected colorectal carcinomas among the three groups (p < 0.01). SATB2 is a useful marker for both primary colorectal carcinoma and corresponding liver metastases, even with neoadjuvant chemotherapy. However, caution should be exercised when performing needle biopsy for metastatic foci with neoadjuvant therapy because expressions could be decreased, especially in chemotherapy-effective cases, and show immunohistochemically negative results.

Diagnostic accuracy of SATB2 in identifying primary and metastatic colorectal carcinoma: a comparative immunohistochemical study

Special AT-rich sequence-binding protein 2 (SATB2) is a new marker that could identify the colonic origin, but whether its expression is preserved in metastatic colorectal carcinomas (CRCs) remains unclear. This study was designed to investigate SATB2 validity in the identification of CRC either alone or in combination with caudal-type homeobox 2 (CDX2) and/or cytokeratin 20 (CK20). Moreover, we examined the concordance of SATB2 expression in primary CRC and paired metastatic specimen. Immunohistochemical expression of SATB2, CDX2 and CK20 was evaluated in primary CRC, 50 paired metastatic CRC and 80 non-CRC specimens. This study demonstrated that the ideal SATB2 cut-off value for recognising colonic from non-colonic origin was 10%. SATB2 was more sensitive and specific than CK20. However, it was more specific but less sensitive than CDX2. Analysing the combined markers expression, SATB2 and CDX2 combination revealed better sensitivity, specificity and larger area under curve compared to SATB2 alone, CDX2 alone and combined CDX2 and CK20. Moreover, SATB2 was able to retain its expression at the metastatic sites. SATB2 was totally concordant between primary CRC and their paired metastatic sites (concordance rate = 100%) with perfect level of agreement. SATB2 could be considered as an accurate diagnostic marker of primary and metastatic CRC. SATB2 and CDX2 is the best combination serving the highest sensitivity and specificity in detection of CRC.

Loss of SATB2 expression correlates with cytokeratin 7 and PD-L1 tumor cell positivity and aggressiveness in colorectal cancer

Colorectal carcinoma (CRC) is a disease that causes significant morbidity and mortality worldwide. To improve treatment, new biomarkers are needed to allow better patient risk stratification in terms of prognosis. This study aimed to clarify the prognostic significance of colonic-specific transcription factor special AT-rich sequence-binding protein 2 (SATB2), cytoskeletal protein cytokeratin 7 (CK7), and immune checkpoint molecule programmed death-ligand 1 (PD-L1). We analyzed a cohort of 285 patients with surgically treated CRC for quantitative associations among the three markers and five traditional prognostic indicators (i.e., tumor stage, histological grade, variant morphology, laterality, and mismatch-repair/MMR status). The results showed that loss of SATB2 expression had significant negative prognostic implications relative to overall survival (OS) and cancer-specific survival (CSS), significantly shortened 5 years OS and CSS and 10 years CSS in patients with CRC expressing CK7, and borderline insignificantly shortened OS in patients with PD-L1 + CRC. PD-L1 showed a significant negative impact in cases with strong expression (membranous staining in 50-100% of tumor cells). Loss of SATB2 was associated with CK7 expression, advanced tumor stage, mucinous or signet ring cell morphology, high grade, right-sided localization but was borderline insignificant relative to PD-L1 expression. CK7 expression was associated with high grade and SATB2 loss. Additionally, a separate analysis of 248 neoadjuvant therapy-naïve cases was performed with mostly similar results. The loss of SATB2 and CK7 expression were significant negative predictors in the multivariate analysis adjusted for associated parameters and patient age. In summary, loss of SATB2 expression and gain of CK7 and strong PD-L1 expression characterize an aggressive phenotype of CRC.

Carcinoma of Unknown Primary Origin: Application of Immunohistochemistry With Emphasis to Different Cytokeratin 7 and 20 Staining Patterns

BACKGROUND

Although the primary origin of some carcinomas may be obscure to clinicians, its identification is crucial as it affects prognosis and treatment (especially novel targeted therapies). Immunohistochemistry (IHC) may be helpful in identifying the primary origin of carcinomas. This retrospective survey aimed to evaluate the frequency and accuracy of each IHC marker used to determine the origin of carcinomas.

METHODS

The review of pathology department archives revealed 307 cases of cancer of unknown primary origin (CUP) between 2015 and 2020, which were accessible in the department archives. Demographic information, site of biopsy, clinical and pathologic diagnoses, and IHC results of the patients were collected.

RESULTS

The patients included 157 (51.15%) men and 150 (48.85%) women. The age of the patients ranged from 14 to 92 years, including 106 (34.5%) expired cases. In 27% of cases, the primary origin of carcinoma remained unknown. The agreement between pathologic and clinical diagnoses was 59%. The most common pattern of cytokeratin (CK) expression in CUP was CK7+/CK20- (55.3%), followed by CK7-/CK20- (19%), CK7+/CK20+ (15%), and CK7-/CK20+ (10.7%), respectively.

CONCLUSION

The IHC analysis may improve the diagnosis of CUPs. However, the origin of some cases remains unknown despite an IHC analysis, thereby necessitating the use of more diagnostic procedures or gene expression studies for reaching a definitive diagnosis.

Regional specific differentiation of integumentary organs: SATB2 is involved in α- and β-keratin gene cluster switching in the chicken

BACKGROUND

Animals develop skin regional specificities to best adapt to their environments. Birds are excellent models in which to study the epigenetic mechanisms that facilitate these adaptions. Patients suffering from SATB2 mutations exhibit multiple defects including ectodermal dysplasia-like changes. The preferential expression of SATB2, a chromatin regulator, in feather-forming compared to scale-forming regions, suggests it functions in regional specification of chicken skin appendages by acting on either differentiation or morphogenesis.

RESULTS

Retrovirus mediated SATB2 misexpression in developing feathers, beaks, and claws causes epidermal differentiation abnormalities (e.g. knobs, plaques) with few organ morphology alterations. Chicken β-keratins are encoded in 5 sub-clusters (Claw, Feather, Feather-like, Scale, and Keratinocyte) on Chromosome 25 and a large Feather keratin cluster on Chromosome 27. Type I and II α-keratin clusters are located on Chromosomes 27 and 33, respectively. Transcriptome analyses showed these keratins (1) are often tuned up or down collectively as a sub-cluster, and (2) these changes occur in a temporo-spatial specific manner.

CONCLUSIONS

These results suggest an organizing role of SATB2 in cluster-level gene co-regulation during skin regional specification.

Delineating the intra-patient heterogeneity of molecular alterations in treatment-naïve colorectal cancer with peritoneal carcinomatosis

In a non-negligible number of patients with metastatic colorectal cancer (mCRC), the peritoneum is the predominant site of dissemination. Cure can be achieved by cytoreductive surgery (CRS) and hyperthermic intraperitoneal chemotherapy (HIPEC), but this procedure is associated with long-term morbidity and high relapse rates. Thus, there is a pressing need for improved therapeutic strategies and complementary biomarkers. The present study explored the molecular heterogeneity in mCRC with peritoneal carcinomatosis (PC), and the potential clinical implications thereof. Multi-region immunohistochemical profiling and deep targeted DNA-sequencing was performed on chemotherapy-naïve tumours from seven patients with synchronous colorectal PC who underwent CRS and HIPEC. In total, 88 samples (5-19 per patient) were analysed, representing primary tumour, lymph node metastases, tumour deposits, PC and liver metastases. Expression of special AT-rich sequence-binding protein 2 (SATB2), a marker of colorectal lineage, was lacking in the majority of cases, and a conspicuous intra-patient heterogeneity was denoted for expression of the proposed prognostic and predictive biomarker RNA-binding motif protein 3 (RBM3). Loss of mismatch repair proteins MLH1 and PSM2, observed in one case, was concordant with microsatellite instability and the highest tumour mutational burden. When present in a patient, mutations in key CRC driver genes, i.e., KRAS, APC and TP53, were homogenously distributed across all samples, while less common mutations were more heterogenous. On the same note, copy number variations showed intra-patient as well inter-patient heterogeneity. In two out of seven cases, hierarchical clustering revealed that samples from the PC and lymph node metastases were more similar to each other than to the primary tumour. In summary, these findings should encourage additional studies addressing the potential distinctiveness of mCRC with PC, which might pave the way for improved personalized treatment of these patients.

Transcription Factor Expression in Sinonasal Neuroendocrine Neoplasms and Olfactory Neuroblastoma (ONB): Hyams' Grades 1-3 ONBs Expand the Spectrum of SATB2 and GATA3-Positive Neoplasms

Sinonasal neuroendocrine neoplasms (SN-NENs) are rare and mostly include neuroendocrine carcinoma (NEC), whereas neuroendocrine tumor (NET) is exceptional in this site. Olfactory neuroblastoma (ONB) is a malignant neuroectodermal neoplasm arising in the nasal cavity. Albeit crucial for correct patients' management, the distinction of high grade ONB from NEC is challenging and requires additional diagnostic markers. The transcription factor SATB2 has been recently introduced in routine diagnostics as an immunohistochemical marker of distal intestine differentiation. No specific data are available about SATB2 and GATA3 expression in SN-NENs. GATA3, SATB2, and, for comparison, CDX2 expression were investigated in a series of epithelial and non-epithelial SN-NENs. We collected 26 cases of ONB and 7 cases of epithelial SN-NENs diagnosed and treated in our Institution. ONBs were graded according to Hyams' system and epithelial NENs were reclassified into 5 NECs, 1 MiNEN, and 1 amphicrine carcinoma. Immunohistochemistry was performed using standard automated protocols. Hyams' grades 1-3 ONBs stained diffusely and intensely for SATB2, whereas grade 4 ONBs and NECs were globally negative. The non-neuroendocrine component of MiNEN and the amphicrine carcinoma were strongly positive. GATA3 was heterogeneously and unpredictably expressed in Hyams' grades 1-3 ONBs, whereas grade 4 ONBs and NECs were completely negative. CDX2 was negative in all cases. Our study identifies, for the first time, SATB2 and GATA3 expression as features of Hyams' grades 1-3 ONBs, expands the spectrum of SATB2 and GATA3-positive neoplasms, and suggests that Hyams' grade 4 ONBs are not only clinically but also biologically different from low graded ONBs.

Immunocytochemistry of effusions: Processing and commonly used immunomarkers

Definitive cytopathological interpretation of some of the effusion fluids may not be possible based on cytomorphological evaluation alone. As discussed in other reviews, this is due to various reasons specifically applicable to effusion fluids including remarkably wide morphologic spectrum of reactive mesothelial cells overlapping with some well to moderately differentiated metastatic carcinoma. The challenge is subject to various factors including level of interpreter training or experience, institutional demographics (such as type of prevalent diseases, predominant sex and age group), technical advances in ancillary support, and expertise in cytopreparatory processing. In such cases immunohistochemistry performed on cell-block sections is simple objective adjunct with or without other ancillary techniques. Ongoing increase in number of immunomarkers along with rabbit monoclonal antibodies with relatively higher affinity is further refining this field. SCIP (subtractive coordinate immunoreactivity pattern) approach, discussed as separate dedicated review article, facilitates refined interpretation of immunoreactivity pattern in coordinate manner on various serial sections of cell-blocks. However, many variables such as delay after specimen collection, specimen processing related factors including fixation and storage; ambient conditions under which paraffin blocks are archived (for retrospective testing); antigen retrieval method; duration of antigen retrieval step; antibody clone and dilution; and antibody application time are common with application of immunohistochemistry in other areas. This review is dedicated to highlight technical aspects including processing of effusion specimens for optimum immunocytochemical evaluation along with commonly used immunomarkers in effusion cytopathology. This review focuses on the technical and general information about various immunomarkers.

Comprehensive clinicopathologic, molecular, and immunologic characterization of colorectal carcinomas with loss of three intestinal markers, CDX2, SATB2, and KRT20

Caudal-type homeobox 2 (CDX2), special AT-rich sequence-binding protein 2 (SATB2), and keratin 20 (KRT20) are frequently used as intestinal epithelium-specific markers in immunohistochemical studies. However, subsets of colorectal carcinomas (CRCs) show loss of these markers. We analyzed The Cancer Genome Atlas data to explore molecular correlates of CDX2, SATB2, and KRT20 genes in 390 CRCs. The decreased mRNA expression of each of the three genes commonly correlated with microsatellite instability-high (MSI-H), CpG island methylator phenotype-high (CIMP-H), BRAF/RNF43 mutations, consensus molecular subtype 1, and high tumor mutational burden. The downregulation of CDX2 or SATB2 was dependent on both MSI-H and CIMP-H, whereas that of KRT20 was more dependent on MSI-H than on CIMP-H. Next, we evaluated the immunohistochemical expression of CDX2, SATB2, and KRT20 in 436 primary CRCs. In contrast to RNA-level expression, decreased expression of CDX2 and SATB2 was more dependent on CIMP-H than on MSI-H. However, consistent with RNA-level expression, decreased expression of KRT20 was more dependent on MSI-H than on CIMP-H. CIMP-H and lymphatic invasion were consistently associated with both CDX2 loss and SATB2 loss in CRCs, regardless of MSI status. In microsatellite stable CRCs, CDX2 loss correlated with BRAF mutation, whereas SATB2 loss was associated with KRAS mutations and decreased T-cell infiltration. Cases with concurrent loss of all three markers were found exclusively in MLH1-methylated MSI-H/CIMP-H CRCs. In conclusion, MSI-H and/or CIMP-H are major common correlates of decreased CDX2/SATB2/KRT20 expression in CRCs, but the specific features associated with the loss of each marker are different in CRCs.

Identification of the most specific markers to differentiate primary pulmonary carcinoma from metastatic gastrointestinal carcinoma to the lung

Background

A number of biomarkers have the potential of differentiating between primary lung tumours and secondary lung tumours from the gastrointestinal tract, however, a standardised panel for that purpose does not exist yet. We aimed to identify the smallest panel that is most sensitive and specific at differentiating between primary lung tumours and secondary lung tumours from the gastrointestinal tract.

Methods

A total of 170 samples were collected, including 140 primary and 30 non-primary lung tumours and staining for CK7, Napsin-A, TTF1, CK20, CDX2, and SATB2 was performed via tissue microarray. The data was then analysed using univariate regression models and a combination of multivariate regression models and Receiver Operating Characteristic (ROC) curves.

Results

Univariate regression models confirmed the 6 biomarkers’ ability to independently predict the primary outcome (p < 0.001). Multivariate models of 2-biomarker combinations identified 11 combinations with statistically significant odds ratios (ORs) (p < 0.05), of which TTF1/CDX2 had the highest area under the curve (AUC) (0.983, 0.960–1.000 95% CI). The sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) were 75.7, 100, 100, and 37.5% respectively. Multivariate models of 3-biomarker combinations identified 4 combinations with statistically significant ORs (p < 0.05), of which CK7/CK20/SATB2 had the highest AUC (0.965, 0.930–1.000 95% CI). The sensitivity, specificity, PPV, and NPV were 85.1, 100, 100, and 41.7% respectively. Multivariate models of 4-biomarker combinations did not identify any combinations with statistically significant ORs (p < 0.05).

Conclusions

The analysis identified the combination of CK7/CK20/SATB2 to be the smallest panel with the highest sensitivity (85.1%) and specificity (100%) for predicting tumour origin with an ROC AUC of 0.965 (p < 0.001; SE: 0.018, 0.930–1.000 95% CI).

Supplementary Information

The online version contains supplementary material available at 10.1186/s13000-021-01184-2.

Novel Diagnostic Biomarkers in Colorectal Cancer

Colorectal cancer (CRC) is still a leading cause of cancer death worldwide. Less than half of cases are diagnosed when the cancer is locally advanced. CRC is a heterogenous disease associated with a number of genetic or somatic mutations. Diagnostic markers are used for risk stratification and early detection, which might prolong overall survival. Nowadays, the widespread use of semi-invasive endoscopic methods and feacal blood tests characterised by suboptimal accuracy of diagnostic results has led to the detection of cases at later stages. New molecular noninvasive tests based on the detection of CRC alterations seem to be more sensitive and specific then the current methods. Therefore, research aiming at identifying molecular markers, such as DNA, RNA and proteins, would improve survival rates and contribute to the development of personalized medicine. The identification of “ideal” diagnostic biomarkers, having high sensitivity and specificity, being safe, cheap and easy to measure, remains a challenge. The purpose of this review is to discuss recent advances in novel diagnostic biomarkers for tumor tissue, blood and stool samples in CRC patients.

Transcriptomic Signatures Associated With Gray Matter Volume Changes in Patients With Functional Constipation

Functional constipation, which belongs to the functional gastrointestinal disorder (FGID), is a common disease and significantly impacts daily life. FGID patients have been progressively proven with functional and structural alterations in various brain regions, but whether and how functional constipation affects the brain gray matter volume (GMV) remains unclear; besides, which genes are associated with the GMV changes in functional constipation is largely unknown. On account of the structural MRI image from the 30 functional constipation patients and 30 healthy controls (HCs), GMV analysis showed that functional constipation patients had significantly decreased GMV in the right orbital prefrontal cortex (OFC), left precentral gyrus (PreG), and bilateral thalamus (THA). Correlation analysis showed that the self-rating depressive scale, patient assessment of constipation quality of life (PAC-QOL), and Wexner constipation scores were negatively correlated with GMV of the OFC and negative correlations between PAC-QOL score and GMV of the bilateral THA. Based on the Allen Human Brain Atlas, a cross-sample spatial correlation was conducted and found that 18 genes’ expression values showed robust correlations with GMV changes in functional constipation patients. These outcomes highlight our recognition of the transcriptional features related to GMV changes in functional constipation and could be regarded as candidates to detect biological mechanisms of abnormality in functional constipation patients.

Breast Metastasis From Rectal Signet-Ring Cell Carcinoma: A Case Report and Review of Literature

BACKGROUND

Metastatic rectal cancer (mRC) of the breast is an extremely rare clinical situation. There are few reported cases in domestic or foreign literature. The clinicopathologic characteristics along with the diagnostic and therapeutic strategies of such cases remain relatively unclear. Here, we would like to provide our comprehensive insights into this rare entity.

METHODS

We present a case that till now is the first reported breast metastasis from rectal cancer pathologically diagnosed as a signet-ring cell carcinoma, and we review the current literature on this rare event. The detailed clinical data, histopathology, management, and follow-up aspects were gathered for analysis.

RESULTS

A total of 15 cases were collected including the current case. Breast metastases from rectal cancer present at an average age of 47.7 years (range, 28 to 69 years) and appear with an average interval of 28.4 months (range, 5 months to 18 years) following primary tumor diagnoses. Of the 15 cases, 8 and 5 are pathologically diagnosed as adenocarcinomas and mucinous adenocarcinomas, respectively. Most cases (11/15) are accompanied by extramammary metastases. About half of the breast metastases (7/15) were to the left. In all cases, the main complaints were palpable mass. The average maximum diameter of the metastatic mass is 2.7 cm (range, 1-11 cm). The majority (8/12) of cases with accessible therapy information exclude the option of local surgery.

CONCLUSION

Previous cancer history and accurate immunohistochemistry data play critical roles to distinguish mammary metastasis from a primary neoplasm of the breast. Mastectomy and molecular-targeted drugs should be considered with priority if systemic condition supports them.

SATB2 and MDM2 Immunoexpression and Diagnostic Role in Primary Osteosarcomas of the Jaw

Primary osteosarcomas of the jaw (OSJ) are rare, accounting for 6% of all osteosarcomas. This study aims to determine the value of SATB2 and MDM2 immunohistochemistry (IHC) in differentiating OSJ from other jawbone mimickers, such as benign fibro-osseous lesions (BFOLs) of the jaw or Ewing sarcoma of the jaw. Certain subsets of osteosarcoma harbor a supernumerary ring and/or giant marker chromosomes with amplification of the 12q13-15 region, including the murine double-minute type 2 (MDM2) and cyclin-dependent kinase 4 (CDK4) genes. Special AT-rich sequence-binding protein 2 (SATB2) is an immunophenotypic marker for osteoblastic differentiation. Cases of OSJ, BFOLs (ossifying fibroma and fibrous dysplasia) of the jaw, and Ewing sarcoma of the jaw were retrieved from the Departments of Oral Pathology and Oral Medicine, Faculty of Dentistry, Obafemi Awolowo University and Lagos State University College of Medicine, Nigeria. All OSJ retrieved showed histologic features of high-grade osteosarcoma. IHC for SATB2 (clone EP281) and MDM2 (clone IF2), as well as fluorescence in situ hybridization (FISH) for MDM2 amplification, were performed on all cases. SATB2 was expressed in a strong intensity and diffuse staining pattern in all cases (11 OSJ, including a small-cell variant, 7 ossifying fibromas, and 5 fibrous dysplasias) except in Ewing sarcoma, where it was negative in neoplastic cells. MDM2 was expressed in a weak to moderate intensity and scattered focal to limited diffuse staining pattern in 27% (3/11) of cases of OSJ and negative in all BFOLs and the Ewing sarcoma. MDM2 amplification was negative by FISH in interpretable cases. In conclusion, the three cases of high-grade OSJs that expressed MDM2 may have undergone transformation from a low-grade osteosarcoma (LGOS). SATB2 is not a dependable diagnostic marker to differentiate OSJ from BFOLs of the jaw; however, it could serve as a valuable diagnostic marker in differentiating the small-cell variant of OSJ from Ewing sarcoma of the jaw, while MDM2 may be a useful diagnostic marker in differentiating OSJ from BFOLs of the jaw, especially in the case of an LGOS or high-grade transformed osteosarcoma.

Ductal breast carcinoma metastasized to the rectum: A case report and review of the literature

BACKGROUND

Gastrointestinal (GI) metastasis from breast cancer (BC) is rarely encountered in clinical practice. Nonspecific symptoms and long intervals make early diagnosis difficult. Therefore, increased awareness of GI metastasis secondary to BC and a deep understanding of the clinical and pathological features, and intervention for GI metastasis are fundamental to avoid delay in correct diagnosis and management.

CASE SUMMARY

The present report discusses the case of a Chinese female patient aged 36 years. The patient presented with difficult defecation along with bloody stools and hypogastralgia. In 2015, she had undergone right modified radical mastectomy and axillary lymph node dissection in another hospital to treat the infiltrating ductal breast carcinoma pT1N1M0. The presenting symptoms were investigated by colonoscopy, which indicated a circumferential stricture in the lower rectum at 3 cm from the anal edge. Further investigation with positron emission tomography-computed tomography revealed an uptake of fluorodeoxyglucose within the distal rectum as well as in the left acetabulum. The samples from laparoscopic exploration were biopsied, which revealed metastases of BC. Immunohistochemical analysis of the tumor confirmed that the patient had rectal metastasis of infiltrating ductal BC.

CONCLUSION

Rectal metastasis should be considered when patients with a history of BC present with changed bowel habits.

SATB2 Defect Promotes Colitis and Colitis-associated Colorectal Cancer by Impairing Cl-/HCO3- Exchange and Homeostasis of Gut Microbiota

BACKGROUND

SATB2 is a diagnostic biomarker and a favourable prognostic marker for colorectal cancer [CRC], but its role in colitis and colitis-associated colorectal cancer [CAC] is unknown.

METHODS

Colitis was induced in intestinal epithelial-specific Satb2 knockout [Satb2 IEC-KO] and control mice using dextran sulphate sodium [DSS]. RNA-seq analysis was performed on colonic tissues, and 16S rDNA-Seq on faecal bacterial DNA from Satb2 IEC-KO and control mice. Immunohistochemistry and flow cytometry were performed to reveal the proportions of different immune cells. Chromatin immunoprecipitation [ChIP] and luciferase reporter were applied to show the regulatory role of SATB2 on SLC26A3, of which the Cl-/HCO3- exchange activity was measured fluorometrically by the pHi-sensitive dye. Bacteroides were detected by fluorescence in situ hybridisation [FISH] on colonic tissue.

RESULTS

Satb2 IEC-KO mice suffered from intestinal epithelial damage spontaneously, and developed more severe colitis and CAC. The expression of SLC26A3 correlated well with SATB2 revealed by RNA-seq and The Cancer Genome Atlas [TCGA] data, and was governed by SATB2 confirmed by ChIP and luciferase reporter experiments. Decreased intestinal flora diversity was seen in Satb2 IEC-KO mice. Bacteroides were more abundant and could colonise into the inner layer of colonic mucosa in Satb2 IEC-KO mice. Faecal microbiome transplantation from Satb2 IEC-KO mice aggravated colitis and M1 macrophages infiltration.

CONCLUSIONS

SATB2 plays a vital role in maintaining intestinal homeostasis, and its deficiency promotes the development of colitis and CAC by influencing the intestinal luminal environment and gut flora.

Expression of nSATB2 in Neuroendocrine Carcinomas of the Lung: Frequent Immunopositivity of Large Cell Neuroendocrine Carcinoma with a Diagnostic Pitfall

Small cell lung carcinoma (SCLC) and pulmonary large cell neuroendocrine carcinoma (LCNEC) are both classified as lung neuroendocrine carcinoma (NEC). It has recently been reported that the special AT-rich sequence-binding protein 2 (STAB2), known as a colorectal cancer marker, is also expressed in NECs occurring in various organs including the lung. However, few studies have examined any differences of SATB2 immunopositivity between SCLC and LCNEC. We investigated SATB2 expression in 45 SCLC and 14 LCNEC cases using immunohistochemistry as well as the expression of caudal-type homeobox 2 (CDX2) and keratin (KRT) 20. The LCNEC cases were more frequently positive for SATB2 (ten out of 14, 71%) than the SCLC ones (seventeen out of 45, 38%) with a statistically significance (P = 0.035). Furthermore, two LCNEC cases were positive for CDX2 while no positive findings were observed for any SCLC cases, the difference of which, however, was not statistically significant (P = 0.053). KRT20 was negative in all LCNEC and SCLC cases. These results require our attention when we use SATB2 and CDX2 as colorectal cancer markers because their expression in pulmonary NECs can lead to a misdiagnosis that the tumor is of metastatic colorectal adenocarcinoma, especially when the patient has a past history of colorectal cancer. Analyzing the relationship between the demographic/clinical variables and the SATB2 expression in the SCLC cases, just high Brinkman index (≥ 600) was significantly related to the positivity of SATB2 (P = 0.017), which is interesting considering the strong relationship between SCLC and smoking.

Loss of SATB2 Occurs More Frequently Than CDX2 Loss in Colorectal Carcinoma and Identifies Particularly Aggressive Cancers in High-Risk Subgroups

Simple Summary

The immunohistochemical analysis of Special AT-rich sequence-binding protein 2 (SATB2) is increasingly being used to detect colorectal differentiation. Our study aimed to investigate SATB2 expression levels and the prognostic relevance of SATB2 loss in colorectal carcinoma (CRC), especially in comparison with CDX2, the standard marker of colorectal differentiation. We tested SATB2 expression in 1039 CRCs and identified SATB2 as a strong prognosticator in the overall cohort as well as in specific subcohorts, including high-risk subgroups. Compared to CDX2, SATB2 showed a higher prognostic power but was lost at a much higher frequency, generally rendering SATB2 as the less sensitive marker for colorectal differentiation compared to CDX2.

Abstract

Background: Special AT-rich sequence-binding protein 2 (SATB2) has emerged as an alternative immunohistochemical marker to CDX2 for colorectal differentiation. However, the distribution and prognostic relevance of SATB2 expression in colorectal carcinoma (CRC) have to be further elucidated. Methods: SATB2 expression was analysed in 1039 CRCs and correlated with clinicopathological and morphological factors, CDX2 expression as well as survival parameters within the overall cohort and in clinicopathological subgroups. Results: SATB2 loss was a strong prognosticator in univariate analyses of the overall cohort (p < 0.001 for all survival comparisons) and in numerous subcohorts including high-risk scenarios (UICC stage III/high tumour budding). SATB2 retained its prognostic relevance in multivariate analyses of these high-risk scenarios (e.g., UICC stage III: DSS: p = 0.007, HR: 1.95), but not in the overall cohort (DSS: p = 0.1, HR: 1.25). SATB2 loss was more frequent than CDX2 loss (22.2% vs. 10.2%, p < 0.001) and of higher prognostic relevance with only moderate overlap between SATB2/CDX2 expression groups. Conclusions: SATB2 loss is able to identify especially aggressive CRCs in high-risk subgroups. While SATB2 is the prognostically superior immunohistochemical parameter compared to CDX2 in univariate analyses, it appears to be the less sensitive marker for colorectal differentiation as it is lost more frequently.

CDX2 and SATB2 positivity in pilomatrix carcinoma: Avoiding an erroneous diagnosis of cutaneous metastasis of gastrointestinal origin

An 80-year-old female presented with a slowly growing 2-cm nodule on her shoulder over a 1-year period. Histopathologic sections of a biopsy specimen showed a multinodular, dermal-based basaloid tumor with areas of clear-cell change, stromal induction, as well as significant cytologic atypia and atypical mitotic activity. An initial investigation revealed positive staining of CDX2, a well-known marker of tumors of gastrointestinal origin. The case was referred to our dermatopathology service for consultation to determine if the lesion was in keeping with a cutaneous metastasis. On receipt of the case, an extended immunohistochemical panel was performed including SATB2, which displayed a similar pattern of staining as seen with CDX2. Although pathologists are most familiar with CDX2 and SATB2 as markers of gastrointestinal origin, the recent dermatopathology literature highlights that primary adnexal lesions of the skin also display positivity for CDX2 and can exhibit SATB2 positivity. We share a case of pilomatrix carcinoma with positive expression of nuclear CDX2 and SATB2, adding to the recent literature to (a) increase recognition of this staining pattern in hair follicle tumors, and (b) discuss briefly the shared molecular underpinnings in the tumorigenesis of gastrointestinal tumors and tumors of hair follicle origin that help clarify this underrecognized immunohistochemical pattern.

SATB2 Is Expressed in a Subset of Pulmonary and Thymic Neuroendocrine Tumors

OBJECTIVES

To evaluate SATB2 expression and prognostic implications in a large cohort of thoracic neuroendocrine tumors.

METHODS

Surgical pathology files (1995-2017) and an institutional thymic epithelial tumor database (2010-2020) were searched for resected neuroendocrine tumors. Cases were stained with SATB2 (clone EP281). Percent SATB2-positive tumor cells and expression intensity were scored.

RESULTS

In the lung, SATB2 was expressed in 5% or more of tumor cells in 29 (74.4%) of 39 small cell carcinomas and 9 (22.5%) of 40 atypical and 26 (40.6%) of 64 typical carcinoid tumors. SATB2 percent tumor cell expression and intensity were higher in small cell carcinomas than in carcinoid tumors (both P < .001, respectively). After adjusting for tumor subtype, SATB2 expression did not correlate with outcome. In the thymus, four (100%) of four atypical carcinoid tumors and one large cell neuroendocrine carcinoma but no small cell carcinoma (n = 2) expressed SATB2 in 5% or more of tumor cells.

CONCLUSIONS

SATB2 (clone EP281) is expressed in a large subset of pulmonary and thymic neuroendocrine tumors and therefore does not appear to be a useful marker to identify the origin of neuroendocrine tumors. Validation studies are needed, specifically including thymic neuroendocrine tumors, as the expression pattern might be different in those tumors.

Poorly differentiated neuroendocrine carcinomas of the gastrointestinal tract: A single-institute study of 43 cases

OBJECTIVES

To characterize the clinicopathologic and immunohistochemical features of poorly differentiated neuroendocrine carcinomas (NEC) in the gastrointestinal tract.

DESIGN

A total of 43 cases were identified and reassessed based on modern classification.

RESULTS

The cohort (27M, 16F; median age: 66 years) included 16 (37%) large cell NEC, 12 (28%) small cell NEC, 5 (12%) NEC not otherwise specified, and 10 (23%) mixed adenoneuroendocrine carcinomas. Tumor predominantly involved the colon (n = 14, 33%), rectum (n = 13, 30%), and esophagus (n = 9, 21%). Immunohistochemically, INSM1 was the most sensitive marker for neuroendocrine differentiation (28/28, 100%), followed by synaptophysin (40/43, 93%), CD56 (22/35, 63%), and chromogranin (18/40, 45%). SATB2, CDX2, CK20, CK7, abnormal p53, and PD-L1 was positive in 21/26 (81%), 26/37 (70%), 11/35 (31%), 10/35 (29%), 19/24 (79%), and 12/23 (52%) cases, respectively. Three of 25 (11%) were mismatch repair protein deficient. Of 21 resected tumors, 19 (90%) were ≥ pT3 and 13 (62%) had nodal metastasis. Twenty-eight (65%) had distant metastasis. The 5-year survival rate was 21%. The prognosis was stage dependent (p < 0.05), but not associated with tumor type, location, or specific immunomarkers.

CONCLUSION

Gastrointestinal NECs are aggressive neoplasms. INSM1, synaptophysin, and SATB2 are sensitive markers, although not site or tumor type specific.

SATB2 Immunoexpression in Peripheral Ossifying Fibroma and Peripheral Odontogenic Fibroma

Peripheral ossifying fibromas (POFs) and peripheral odontogenic fibromas (POdFs) appear clinically similar but of different histogenesis. The novel marker SATB2 is involved in regulation of osteoblastic differentiation and phenotype. However, SATB2 expression has not been previously explored in POFs and POdFs. Given the potential for mineralized tissue formation in POFs and POdFs, and to more clarify the phenotype of the lesional cells, this study was aimed to immunohistochemically investigate SATB2 expression in POFs and POdFs. Fourteen cases of POF and POdF (7 cases each) were selected, stained for SATB2 immunohistochemically, and scored according to the percentage of positive lesional cells (0, no staining; 1 +, < 5%; 2 +, 5-25%; 3 +, 26-50%; 4 +, 51-75%; and 5 +, 76-100%), and the intensity of staining was graded as weak, moderate, or strong. The control group included the inflammatory fibrous hyperplasia-like area present in two cases, 1 case fibroma, and 1 case giant cell fibroma. Moderate to strong, and diffuse SATB2 nuclear immunoreactivity was detected in the lesional cells of all cases of POFs and POdFs with variable scores; 3-5 + for the POFs and 3-4 + for the POdFs (P = 0.101). The distribution of staining was more prominent in those lesional cells associated with the osteoid/calcification in the cases of POFs. No staining was noted in the control group. The lesional cells in both POFs and POdFs express SATB2 and may exhibit the osteoblastic-like phenotype. SATB2 staining may be useful for diagnosis of subsets of POFs with minimal or absent calcification and some POdFs with unidentifiable odontogenic epithelium.