Cytopathological features of secretory carcinoma of salivary glands and ancillary techniques in its diagnostics: impact of new Milan system for reporting salivary gland cytopathology.

Secretory carcinoma (SC) of salivary glands is a newly described low-grade malignancy characterized by the presence of ETV6 rearrangement. Only a few cases and very small series with cytomorphology were reported so far. Six cases of fine-needle aspirations (FNAs) from afterward histologically, immunohistochemically and genetically confirmed SCs were retrieved from the archives of the authors. Ancillary immunocytochemistry (ICC) and translocation detection were performed on cell blocks (CBs). All aspirates were sufficiently cellular and cells were arranged in more or less cohesive groups with only mild nuclear polymorphism. The cytoplasm was eosinophilic, granulated and vacuolated, especially in CBs. Secretory material within the microcystic spaces was periodic acid-Schiff (PAS) positive. Triple positivity of immunomarkers S-100 protein, mammaglobin and vimentin was present. The proliferation index was low. Ancillary techniques suggested the possibility of SC in a few cytology cases; nevertheless, the final diagnosis was based on histomorphology, immunohistochemistry and genetics. The SC of salivary glands is detectable pre-operatively using ICC and genetics. The presence of the diagnostic ETV6 rearrangement increases the accuracy of FNA to the maximum. According to the Milan system, cases genetically not confirmed should be categorized as Suspicious for Malignancy or Salivary Gland Neoplasm of Uncertain Malignant Potential (SUMP), both requiring surgery.

Molecular methods for detection of prognostic and predictive markers in diagnosis of adenoid cystic carcinoma of the salivary gland origin.

Adenoid cystic carcinoma of salivary gland origin (AdCC) is second most common salivary carcinoma characterized by frequent recurrences, perineural invasion and high long-term mortality rate. The surgical resection of the tumor in combination with adjuvant radiotherapy is the only method of choice. AdCC has been studied, altogether with immunohistochemistry, by numerous molecular-genetic techniques. Some of them, e.g. reverse-transcription PCR or fluorescent in situ hybridization contributed to the identification of translocation t(6;9)(q22-23;p23-24), which results in fusion of two transcription factors MYB-NFIB. For AdCC is this fusion unique among salivary gland carcinomas and serves as a diagnostical tool in differential diagnosis of histopathologically difficult cases. More complex methods, such as next-generation sequencing helped to detect other molecular level changes; and hence improved understanding of a development, behavior and pathogenesis of this possibly fatal malignancy. This review summarizes basic knowledge of AdCC on the genome, transcriptome and epigenetic level, which were achieved using molecular-genetic and immunohistochemical methods. Keywords: adenoid cystic carcinoma - salivary carcinoma - MYB-NFIB - FISH - aCGH - NGS.

Immunohistochemical and selected genetic reflex testing of all uterine leiomyosarcomas and STUMPs for ALK gene rearrangement may provide an effective screening tool in identifying uterine ALK-rearranged mesenchymal tumors.

We examined the value of targeted molecular screening for the identification of uterine anaplastic lymphoma kinase (ALK)-rearranged mesenchymal tumors, including ALK immunohistochemistry followed by molecular genetic testing, in all uterine leiomyosarcomas and STUMPs (smooth muscle tumors of uncertain malignant potential). All leiomyosarcoma and STUMP cases diagnosed in a 10-year period (2006-2016) at Charles University Faculty of Medicine in Pilsen were retrieved and reviewed. Of 23 cases, one case (LMS [leiomyosarcoma]) was positive for ALK rearrangement, namely, PPP1CB-ALK fusion gene. No specific histologic features (i.e., lymphocytic infiltrate and stromal edema) were observed in this case. This suggests that inflammatory myofibroblastic tumor (IMT)-like histologic features may not be an initial reliable screening tool in identifying uterine IMT cases. Thus, we proposed a two-step IHC and molecular genetic testing (as a reflex test) for IMT in all uterine LMS and STUMP cases. This will enhance the proper detection of such tumors at the population level and ultimately offer patients available targeted therapies.

Molecular Profiling of Salivary Gland Intraductal Carcinoma Revealed a Subset of Tumors Harboring NCOA4-RET and Novel TRIM27-RET Fusions: A Report of 17 cases.

Intraductal carcinoma (IC) is the new World Health Organization designation for tumors previously called "low-grade cribriform cystadenocarcinoma" and "low-grade salivary duct carcinoma." The relationship of IC to salivary duct carcinoma is controversial, but they now are considered to be distinct entities. IC is a rare low-grade malignant salivary gland neoplasm with features similar to mammary atypical ductal hyperplasia or ductal carcinoma in situ, that shows diffuse S100 protein and mammaglobin positivity and is only partially defined genetically. (Mammary analogue) secretory carcinoma harboring ETV6-NTRK3, and in rare cases ETV6-RET fusion, shares histomorphologic and immunophenotypical features with IC. Recently, RET rearrangements and NCOA4-RET have been described in IC, suggesting a partial genetic overlap with mammary analogue secretory carcinoma. Here, we genetically characterize the largest cohort of IC to date to further explore this relationship. Seventeen cases of IC were analyzed by next-generation sequencing using the FusionPlex Solid Tumor kit (ArcherDX). Identified fusions were confirmed using fluorescence in situ hybridization break apart and, in some cases, fusion probes, and a reverse transcription polymerase chain reaction designed specifically to the detected breakpoints. All analyzed cases were known to be negative for ETV6 rearrangement by fluorescence in situ hybridization and for ETV6-NTRK3 fusion by reverse transcription polymerase chain reaction. Next-generation sequencing analysis detected a NCOA4-RET fusion transcript joining exon 7 or 8 of NCOA4 gene and exon 12 of RET gene in 6 cases of intercalated duct type IC; and a novel TRIM27-RET fusion transcript between exons 3 and 12 in 2 cases of salivary gland tumors displaying histologic and immunohistochemical features typical of apocrine IC. A total of 47% of IC harbored a fusion involving RET. In conclusion, we have confirmed the presence of NCOA4-RET as the dominant fusion in intercalated duct type IC. A novel finding in our study has been a discovery of a subset of IC patients with apocrine variant IC harboring a novel TRIM27-RET.

Molecular Profiling of Hyalinizing Clear Cell Carcinomas Revealed a Subset of Tumors Harboring a Novel EWSR1-CREM Fusion: Report of 3 Cases.

We describe a novel gene fusion, EWSR1-CREM, identified in 3 cases of clear cell carcinoma (CCC) using anchored multiplex polymerase chain reaction, a next-generation sequencing-based technique. CCC is a low-grade salivary tumor recently characterized to have EWSR1-ATF1 fusions in the majority of cases. Three cases of malignant tumor presenting in the base of tongue, lung, and nasopharynx were studied. All cases shared a clear cell morphology with hyalinized stroma, presence of mucin and p63 positivity and were initially diagnosed as mucoepidermoid carcinoma but were negative for evidence of any of the expected gene fusions. Anchored multiplex polymerase chain reaction demonstrated a EWSR1-CREM fusion in all 3 cases to confirm a diagnosis of CCC. This finding is biologically justified as CREM and ATF1 both belong to the CREB family of transcription factors. EWSR1-CREM fusions have not been previously reported in CCC and have only rarely been reported in other tumors. We show that the ability to discover novel gene variants with next-generation sequencing-based assays has clinical utility in the pathologic classification of fusion gene-associated tumors.

Solid pseudopapillary neoplasm (SPN) of the testis: Comprehensive mutational analysis of 6 testicular and 8 pancreatic SPNs.

BACKGROUND: Recently, we came with the theory of a possible relationship between a group of testicular and pancreatic tumors. We used one case of a pancreatic analogue solid pseudopapillary neoplasm of the testis composed partially of areas reminiscent of solid pseudopapillary neoplasm (SPN) of the pancreas and partially of structures identical to primary signet ring stromal tumor of the testis (PSRSTT) as a connecting link between these two entities. After demonstrating that PSRSTT and pancreatic analogue SPN of the testis share the same immunoprofile and genetic features characteristic for pancreatic SPN, we came to the conclusion that pancreatic analogue SPN of the testis and PSRSTT represent a morphological spectrum of a single entity and that both are related to the pancreatic SPN. DESIGN: The aim of this study is to present a series of 6 cases of testicular tumors, which lacked the signet ring cell component and were thus morphologically very similar to the SPN of the pancreas. The goal of this study is to compare the genetic background of these testicular tumors that are obviously related to the PSRSTT/pancreatic analogue SPN of the testis with the series of 8 pancreatic SPN. RESULTS: The mutational analysis revealed an oncogenic somatic mutation in the exon 3 of the CTNNB1 (ß-catenin) gene in all analyzable (5/6) testicular and all pancreatic (8/8) tumors. The immunoprofile (positivity with ß-catenin, CD10, vimentin, NSE, CD56, and negativity with inhibin, calretinin, chromogranin) was identical in all testicular and pancreatic tumors. CONCLUSION: This study expanded the morphological spectrum of the PSRSTT/pancreatic analogue SPN of the testis by adding 6 cases without the signet ring cell component. Considering the obvious analogy of PSRSTT/pancreatic analogue SPN of the testis/SPN of the testis and their relationship to the pancreatic SPN we propose the collective term "solid pseudopapillary neoplasm of the testis" for these tumors. The mutational profile of the SPN of the testis and pancreas was the same in both groups of tumors which we consider as a final proof that SPN of the testis is identical to the SPN of the pancreas.

Prognostic significance of 1p36 locus deletion in adenoid cystic carcinoma of the salivary glands.

Adenoid cystic carcinoma (AdCC) of the salivary glands is characterized by MYB-NFIB or MYBL1-NFIB fusion, prolonged but relentlessly progressive clinical course with frequent recurrences, and development of distant metastasis resulting in high long-term mortality. Currently, no effective therapy is available for patients with advanced non-resectable and/or metastatic disease. Complicating the clinical management of this patient group is the lack of prognostic markers. The purpose of this study is to investigate the prognostic value of 1p36 loss in patients with AdCC. The presence of 1p36 deletion and gene fusions involving the MYB, NFIB, and MYBL1 genes in a cohort of 93 salivary gland AdCCs was studied using fluorescence in situ hybridization. These results were statistically correlated with clinical data and outcome. Deletion of 1p36 in AdCC was identified in 13 of 85 analyzable cases (15.29%). MYB-NFIB fusion was detected in 57/85 (67.1%), MYBL1-NFIB fusion in 12/85 (14.1%), MYB-X fusion in 4/85 (4.7%), MYBL1-X in 4/85 (4.7%), and NFIB-X in 2/85 (2.4%) of AdCC cases. None of the 1p36-deleted samples showed MYBL1 rearrangement. Statistical analysis demonstrated a significant correlation between 1p36 deletion and advanced tumor stage and solid histology (p = 0.0061 and 0.0007, respectively). Kaplan-Meier survival curves showed statistically significant correlations between 1p36 deletion and decreased overall survival, disease-specific survival, recurrence-free interval, and recurrence-free survival, all of which were maintained in multivariate analysis. We demonstrate that 1p36 deletion can serve as an indicator of unfavorable outcome of patients with salivary gland AdCC.

Mammary Analog Secretory Carcinoma of the Nasal Cavity: Characterization of 2 Cases and Their Distinction From Other Low-grade Sinonasal Adenocarcinomas.

Secretory carcinoma, originally described as mammary analog secretory carcinoma (MASC), is a low-grade salivary gland tumor characterized by a t(12;15)(p13;q25) translocation, resulting in an ETV6-NTRK3 gene fusion. Most MASCs are localized to the parotid gland and intraoral minor salivary glands. Moreover, ETV6-rearranged carcinomas with secretory features have been reported recently in the thyroid (with and without a history of radiation exposure), skin, and in very rare instances in the sinonasal tract. Here, we describe 2 cases of primary MASC in the sinonasal tract and provide a detailed clinical and histopathologic characterization of their morphology, immunohistochemical profile, and genetic background and highlight features allowing for its separation from its recently described molecular mimicker, ETV6-rearranged low-grade sinonasal adenocarcinoma.

The Role of SATB2 as a Diagnostic Marker of Sinonasal Intestinal-type Adenocarcinoma.

BACKGROUND: Intestinal-type adenocarcinoma (ITAC) of the nasal cavity and paranasal sinuses is an uncommon tumor associated with exposure to wood and leather dust, nickel, and possibly smoking. ITAC shares phenotypical features with colorectal carcinoma. In contrast to most non-intestinal-type sinonasal adenocarcinomas, ITAC is an aggressive adenocarcinoma with poor clinical outcome; therefore, its reliable separation from non-ITAC is very important. AIM: The use of a combination of immunohistochemical markers of intestinal differentiation was tested in a cohort of sinonasal carcinomas of different types. The aim of this study was to explore a new intestinal marker, SATB2, in conjunction with CDX2 and CK20 in differential diagnosis of sinonasal adenocarcinomas. MATERIALS AND METHODS: Seven ITACs, 66 non-ITACs, and 1 case of extensive intestinal metaplasia (IM) of the nasal mucosa were included in the study and stained with SATB2, CK20, CDX2, and CK7 antibodies. Detection of mismatch repair proteins was performed in all cases of ITAC. All 7 sinonasal ITACs have been tested for KRAS, NRAS, and BRAF gene mutations. RESULTS: All ITACs showed positive expression for SATB2, whereas all non-ITAC cases were negative. The only 1 case of IM was found to be positive for SATB2, whereas the same case showed negative expression of CK20 and only focal immunostaining for CDX2. The genetic analysis showed that only 1 sinonasal ITAC (1/7) showed KRAS c.35G>C, p.(Gly12Ala) mutation, whereas BRAF and NRAS genes were wild type. Four ITACs revealed wild-type KRAS, NRAS, and BRAF, and 2 remaining cases were not analyzable. All ITACs showed preserved nuclear expression of mismatch repair proteins. CONCLUSIONS: SATB2 in combination with CDX2 and CK20 differentiates sinonasal ITAC from non-ITAC with increased diagnostic sensitivity and specificity and detects IM in the sinonasal tract more easily.

[Hamartoma of mature cardiac myocytes. Autopsy case report]. / Hamartom ze zralých kardiomyocytu. Pitevní kazuistika.

Hamartoma of mature cardiac myocytes (HMCM) is a rare benign pseudoneoplastic myocardial lesion. We describe a case of 39-year-old Bulgarian woman living in the Czech Republic, who died because of rupture of anterior communicating artery aneurysm, and severe bronchopneumonia. An incidental finding at the autopsy was a whitish unencapsulated and not sharply demarcated tumor of the left ventricle and adjacent area of interventricular septum, which protruded above the plane of section. Microscopically the tumor consisted of various different forms of disorganized hypertrophic mature cardiac myocytes without vacuolization of cytoplasm, focally in a "herringbone" pattern. Dilated venules and thickened intramural coronary arteries, and intervening bands of connective tissue were present between cardiomyocytes in the tumor. Immunohistochemical staining of MIB1 for the detection of proliferative activity was completely negative. No inflammatory infiltration, adipose tissue or calcifications were present in the tumor.

Differentiated squamous intraepithelial lesion (dSIL)-like changes in the epidermis overlying anogenital melanocytic nevi: A diagnostic pitfall.

BACKGROUND: Differentiated squamous intraepithelial lesion (dSIL) is morphologically and immunohistochemically analogous in the whole anogenital region. dSIL is a premalignant lesion frequently misinterpreted histopathologically as a benign dermatosis. The authors describe a peculiar change in the basal cell layer of the epidermis/epithelium overlying anogenital melanocytic nevi that may histopathologically imitate dSIL. The aim of this study is to familiarize the pathologists with this pitfall to avoid its possible overdiagnosis as dysplasia. Further, we tried to explore the biological characteristics of the dSIL-like changes and to focus on the differential diagnostic aspects. DESIGN: Seventy cases of anogenital nevi were retrieved from our registry. All cases were stained with hematoxylin and eosin (H&E) and reviewed. Cases in which the epidermis overlying nevi featured atypical appearing basal keratinocytes in otherwise fully differentiated epithelium, variable degrees of acanthosis and parakeratosis were selected for additional investigation. RESULTS: Thirty cases meeting the above described criteria were identified. The patients were 8 males and 22 females, with age at the time of diagnosis ranging from 4 to 68years. Follow-up data were available for 28 patients (range 0.5-19years, mean 5.1), and to date, no signs of epithelial malignancy have been recorded. Immunohistochemically (IHC), the epidermis overlying nevi showed insignificant positivity for p53 in all tested cases. Melanocytic markers (S-100 protein, SOX10, Melan A) and cytokeratin AE1/3 labeled melanocytes and keratinocytes, respectively, enabling their distinction, especially in nevi featuring a junctional component. CONCLUSIONS: Differentiated squamous intraepithelial lesion-like changes seem to occur relatively often in the epidermis overlying anogenital melanocytic nevi. Since morphologically they are virtually identical to the "true" dSIL, their distinction largely depends on p53 expression in basal keratinocytes with normal p53 expression in dSIL-like changes and diffuse nuclear/p53-null immunostaining in the "true" dSIL serving as an essential differential diagnostic tool. dSIL-like alterations seem to have no malignant potential, as to date, none of the patients included in this study have shown any signs of epithelial malignancy.

Littoral cell angioma of the spleen: a study of 25 cases with confirmation of frequent association with visceral malignancies.

AIMS: Littoral cell angioma (LCA) is a rare primary splenic tumour that is frequently associated with internal malignancies. Immunohistochemistry can demonstrate a distinct hybrid endothelial-histiocytic phenotype of littoral cells, and is a helpful adjunct for making the correct diagnosis. The aims of this study were to present a series of 25 LCAs, with an emphasis on the frequent association of the neoplasm with visceral malignancies, and to provide a detailed immunohistochemical analysis by employing new markers. METHODS AND RESULTS: All 25 cases with available tissue blocks were immunohistochemically stained for endothelial and histiocytic markers. Clinical and follow-up data were retrieved from the respective institutions. The tumours were obtained from 16 males and nine females, whose age ranged from 32 to 86 years (mean 56.2 years). Clinical information was available for 24 of 25 patients, and follow-up for 11 of 25 patients (range 2-19 years; mean 11.6 years). Immunohistochemically, all cases were positive for LYVE-1, factor VIII, FLI-1, vascular endothelial growth factor receptor (VEGFR)-2, VEGFR-3, claudin-5, ERG, LMO2, CD31, CD163, lysozyme, and CD4, but negative for D2-40, CD8, and factor XIIIa. Fifteen of 25 cases were associated with various malignancies, including epithelial, mesenchymal and haematological tumours. CONCLUSIONS: The cohort of 25 patients is the largest series of LCAs published to date. By using antibodies against recently introduced endothelial markers, we have expanded the immunoprofile of LCA. We have further highlighted the clinical significance of LCA, as more than half of the patients in this study also harboured a coexisting visceral malignancy. Therefore, we conclude that the finding of splenic LCA mandates a thorough clinical evaluation for a concomitant malignancy.

Penile Analogue of Stratified Mucin-Producing Intraepithelial Lesion of the Cervix: The First Described Case. A Diagnostic Pitfall.

The authors report a case where undifferentiated (classic) penile intraepithelial neoplasia was associated with the presence of goblet cells throughout the full epithelial thickness and which later progressed into an invasive carcinoma. The lesion evolved in three consecutive biopsies from only surface epithelium occupying numerous goblet cells in the first to variably sized solid nodules in the dermis composed of atypical squamous and/or basaloid cells intermixed with numerous goblet cells in the third biopsy. Both cellular components expressed CK7 and p16 protein. Human Papillomavirus (HPV) genotyping revealed high risk HPV type 16. To the best of our knowledge, this is the first description of such a lesion occurring on the penis, which can be considered the penile analogue of cervical stratified mucin-producing intraepithelial lesion (SMILE). The correct diagnosis was rendered retrospectively, after recognition of the existence of a vulvar lesion resembling cervical SMILE. The initial biopsy was misinterpreted as extramammary Paget disease, which also constitutes the main pitfall in the differential diagnosis. Another important differential diagnosis is penile/vulvar mucinous metaplasia. The finding of atypical squamous epithelial cells positive for p16 associated with mucinous cells present throughout the full epithelial thickness is a clue to the diagnosis of penile SMILE.