Utility of Immunohistochemistry With Antibodies to SS18-SSX Chimeric Proteins and C-Terminus of SSX Protein for Synovial Sarcoma Differential Diagnosis.

Synovial sarcoma is a relatively common soft tissue tumor characterized by highly specific t(X;18)(p11;q11) translocation resulting in the fusion of SS18 with members of SSX gene family. Typically, detection of SS18 locus rearrangement by fluorescence in situ hybridization or SS18 :: SSX fusion transcripts confirms the diagnosis. More recently, immunohistochemistry (IHC) for SS18-SSX chimeric protein (E9X9V) and C-terminus of SSX (E5A2C) showed high specificity and sensitivity for synovial sarcoma. This study screened a cohort of >1000 soft tissue and melanocytic tumors using IHC and E9X9V and E5A2C antibodies. Three percent (6/212) of synovial sarcomas were either negative for SS18-SSX or had scattered positive tumor cells (n=1). In these cases, targeted RNA next-generation sequencing detected variants of SS18 :: SSX chimeric transcripts. DNA methylation profiles of 2 such tumors matched with synovial sarcoma. A few nonsynovial sarcoma tumors (n=6) revealed either focal SS18-SSX positivity (n=1) or scattered positive tumor cells. However, targeted RNA next-generation sequencing failed to detect SS18 :: SSX transcripts in these cases. The nature of this immunopositivity remains elusive and may require single cell sequencing studies. All synovial sarcomas showed positive SSX IHC. However, a mosaic staining pattern or focal loss of expression was noticed in a few cases. Strong and diffuse SSX immunoreactivity was also seen in epithelioid sclerosing osteosarcoma harboring EWSR1 :: SSX1 fusion, while several sarcomas and melanocytic tumors including cellular blue nevus (5/7, 71%) revealed focal to diffuse, mostly weak to intermediate SSX staining. The SS18-SSX and SSX IHC is a useful tool for synovial sarcoma differential diagnosis, but unusual immunophenotype should trigger molecular genetic testing.

PRAME Expression in Cancer. A Systematic Immunohistochemical Study of >5800 Epithelial and Nonepithelial Tumors.

Preferentially expressed antigen in melanoma (PRAME) is considered a useful marker in the differential diagnosis between malignant melanoma and its melanocytic mimics. Recently PRAME expression was documented in nonmelanocytic tumors, but much of the data are based on mRNA studies. This investigation evaluated PRAME expression in the spectrum of normal tissues and >5800 human tumors using immunohistochemistry and EP461 monoclonal antibody. In normal tissues, PRAME was expressed in the testis and proliferative endometrium. In tumors, PRAME was variably expressed in malignancies of different lineages. Among epithelial tumors, >50% of PRAME-positive lesions were found among endometrial carcinomas (82%), uterine serous carcinomas (82%), uterine carcinosarcomas (60%), ovarian clear cell carcinomas (90%), ovarian serous carcinomas (63%), adenoid cystic carcinomas (81%), seminomas (78%), thymic carcinomas (75%), and basal cell carcinomas (62%). In mesenchymal and neuroectodermal malignancies, PRAME was frequently expressed in synovial sarcoma (71%), myxoid liposarcoma (76%), neuroblastoma (61%) and metastatic melanoma (87%). Also, PRAME was consistently expressed in 4 melanomas that lacked all melanoma markers including S100 protein and SOX10 but harbored typical for melanoma BRAF or NRAS driver mutations. However, strong and diffuse PRAME immunoreactivity was seen in many types of nonmelanocytic poorly differentiated carcinomas and sarcomas. Based on this study, PRAME is a relatively unspecific immunohistochemical marker, which limits its use in diagnostic surgical pathology. However, immunohistochemistry is a reliable and unexpensive method useful in detecting PRAME-positive malignancies for potential immunotherapy.

Primary cardiac atrial sarcomas. Report of two histologically different cases and review of the literature.

Primary cardiac sarcomas are extremely uncommon. We report two patients with primary cardiac atrial sarcomas: a case report of a 34-year old woman with intimal sarcoma of the left atrium and a case report of a 30-year old man with synovial sarcoma of the right atrium. Clinicopathological and differential diagnosis with a discussion regarding the role of molecular studies is presented.

High Ki-67 expression is a marker of poor survival in apocrine breast carcinoma.

Apocrine carcinoma is a very rare type of breast cancer, which represents 0.5-4% of all breast cancers. The aim of the study was to analyze biological and clinical features of apocrine carcinoma and their influence on patients survival. The studied group consists of 57 patients, who underwent treatment between 1987 and 2010. Expression of ER, PgR, HER2, AR, GCDFP-15, EGFR, CK 5/6, CK 8/18 and Ki-67 was assessed immunohistochemically on formalin-fixed paraffin-embedded tissue sections. Presence of emboli and extent of lymphocyte infiltration were assessed on haematoxylin-eosin-stained slides. In the investigated group, 16 cases were ER/PgR positive and 49 were AR-positive. ER/PgR-negative tumours were often characterised by CK5/6 and EGFR positivity. The presence of AR was related to HER-2 and GCDFP-15 expression and tumours with expression of CK5/6 were more likely be EGFR positive and had higher Ki-67 LI. Higher probability of 10-years OS and DFS was observed in patients with tumours characterized by Ki-67 LI < 20% (p = 0.036 and p = 0.009, respectively). Favourable trend in OS was noted for patients with smaller tumours (p = 0.053), without lymph node metastases (p = 0.074) and without EGFR expression (p = 0.060). In apocrine breast carcinoma expression of Ki-67 is one of the most important factors influencing patients' survival.

Synovial sarcoma of the stomach: case report and systematic review of the literature.

Synovial sarcoma is a rare mesenchymal malignant neoplasm that presents a specific t(X;18) translocation forming SS18(SYT)-SSX chimera gene. It is most commonly seen in soft tissues of the extremities. The digestive tract is an exceptional site of involvement. We report a case of primary gastric synovial sarcoma in a 48-year-old female. Differential diagnosis of synovial sarcoma from other spindle cell, mesenchymal and cytokeratin-positive tumors is critical for the treatment and prognosis. Immunohistochemistry studies and molecular analysis are required to settle a proper diagnosis.

Molecular prognostic factors in early-stage cervical adenocarcinoma.

Within the past years the proportion of cervical adenocarcinomas has increased, however, there is a shortage of data regarding immunohistochemical and molecular features and their prognostic relevance in early-stage cervical adenocarcinoma (esCAC). Aim of the present study was to evaluate molecular prognostic factors in esCAC patients treated with primary surgery. Analyses of surgical specimens in 59 patients with esCAC were performed on fixed paraffin-embedded sections of tumour tissue. Tumour tissue sections were routinely stained with hematoxylin and eosin followed by microscopic examination. Immunohistochemical analyses (IHC) were performed on paraffin-embedded section. Flow cytometry (FCM) analysis of paraffin-embedded tumor tissue was performed using flow cytometer FACSCalibur equipped with argon laser. DNA histogram analysis was performed with ModFit application. Treatment effectiveness was evaluated using overall 5-year survival. Survival probability was estimated using the Kaplan-Meier method. Overall survival rate estimated using Kaplan-Meier method was 74.6%. Among the IHC and FCM features univariate analysis showed statistical significance of nm23-H1 gene expression and total S-phase fraction ≤ 11.9% (S-TOT). In multi- variate analysis LVSI and parametrial involvement had significant, negative impact on survival (HR = 8.04, p < 0.003 and HR = 4.03, p < 0.017, respectively). However, none of the tested IHC and FCM features had any influence on overall 5-year survival.

Relationship between HER2 gene status and selected potential biological features related to trastuzumab resistance and its influence on survival of breast cancer patients undergoing trastuzumab adjuvant treatment.

BACKGROUND: The aim of the study was to investigate if parameters associated with human epidermal growth factor receptor type 2 (HER2) status (HER2 gene copy number, HER2/CEP17 ratio or polysomy of chromosome 17) are related to various biological features potentially responsible for trastuzumab resistance (PTEN, IGF-1R, MUC4, EGFR, HER3, HER4, and mutation status of PIK3CA) as well as their influence on survival of HER2-positive breast cancer patients treated with adjuvant chemotherapy and trastuzumab. PATIENTS AND METHODS: The investigated group consisted of 117 patients with invasive ductal breast cancer (T≥1, N≥0, M0) with overexpression of HER2, who underwent radical surgery between 2007 and 2014. Status of ER, PR, and HER2 expression was retrieved from patients' files. HER2 gene copy number was investigated by fluorescence in situ hybridization using PathVysion HER-2 DNA Probe Kit II. Expression of PTEN, IGF-1R, MUC4, EGFR, HER3, and HER4 was assessed immunohistochemically on formalin-fixed paraffin-embedded tissue sections. PIK3C mutation status was determined by qPCR analysis. RESULTS: Overexpression of HER2 protein (IHC 3+) and ER negativity corresponded to higher HER22 copy number and HER2/CEP17 ratio (.<0.001). Tumors with polysomy were characterized by higher HER22 gene copy number but lower HER2/CEP17p ratio (p<0.026, p<0.001). Patients with tumors featuring HER3 immunonegativity or low HER2/CEP17 ratio (#4) were characterized by 100% metastasis-free survival (.=0.018, p=0.062). CONCLUSION: Presence of both unfavorable factors, ie, HER3 expression and high HER2/CEP17 ratio, allowed to distinguish a group of patients with worse prognosis (.=0.001).

Podoplanin-positive Cancer-associated Stromal Fibroblasts in Primary Tumor and Synchronous Lymph Node Metastases of HER2-overexpressing Breast Carcinomas.

We compared the status of stromal podoplanin-positive cancer-associated fibroblasts (ppCAFs) between primary tumors and paired synchronous lymph node metastases (LNMs) and analyzed the prognostic significance of tumoral ppCAFs in 203 patients with human epidermal growth factor receptor 2-positive breast carcinoma. ppCAFs were found in 167/203 and in 35/87 tumors and LNM, respectively. ppCAFs were most frequently found in tumors and corresponding LNM (n=52, 59.8%; p=0.001). However, for all LNMs (n=12) without ppCAFs, their paired tumors also lacked ppCAFs. In both tumors and LNMs, ppCAFs were α-smooth muscle actin-positive and cluster of differentiation 21 protein-negative, suggesting them not to be resident lymph node cells. Moreover, in our series, the presence of ppCAFs in tumors was borderline related to poor disease-free survival (p=0.058). These results speak in favor of a hypothesis suggesting ppCAFs accompany metastatic cancer cells migrating from tumor to LNMs.

Malignant gastrointestinal neuroectodermal tumor (clear cell sarcoma-like tumor of the gastrointestinal tract) of the small intestine in a 12-year-old boy.

The aim of this paper is a clinical and anatomopathological demonstration of a malignant lesion, a gastrointestinal neuroectodermal tumor (GNET), as an exceedingly rare cause of ileus in the pediatric population. Specifically, we present the case of a 12-year-old boy who showed dramatic weight loss, hypochromic anemia, fever, dehydration, exaggerated granulation of the terminal ileum, and mechanical ileus due to the obstruction by an intramural tumor of the small intestine. A 50cm-long part of the small intestine with pathological stricture was surgically removed, sampled and routinely fixed and stained with hematoxylin and eosin. The additional immunostains that were preformed were: PAS, S-100, HMB-45, NSE, LCA, CK AE1 / AE3, desmin, SMA, vimentin, CD99, NSE, synaptophysin, WT-1, calretinin, and DOG-1. Moreover, fluorescent in situ hybridization (FISH) with the EWSR1 Break Apart FISH Probe was applied. The neoplasm was composed of nests and alveolar patterns of frankly malignant clear cells with immunoreactivity to S-100, vimentin, and CD 99. The FISH technique detected chromosomal breaking at 22q12. The tumor metastasized to both the mesenteric lymph nodes and a number of hepatic segments. With several chemotherapy protocols, repeat laparotomies, and liver thermal ablations, the patient had a 1.5-year-long survival from the moment of diagnosis. The diagnosis of this malignancy requires both histopathological evaluation and molecular analysis, and the follow-up is based on careful clinical imaging of the neoplastic spread in order to apply proper surgical and oncological treatments. In conclusion, the clinical course of GNET was highly aggressive.

Application of high-resolution genomic profiling in the differential diagnosis of liposarcoma.

BACKGROUND: Rarity and heterogeneity of liposarcomas (LPS) make their diagnosis difficult even for sarcoma-experts pathologists. The molecular mechanism underlying the development and progression of liposarcomas (LPS) remains only partially known. In order to identify and compare the genomic profiles, we analyzed array-based comparative genomic hybridization (array-CGH) profiles of 66 liposarcomas, including well-differentiated (WDLPS), dedifferentiated (DDLPS) and myxoid (MLPS) subtypes. RESULTS: Copy number aberrations (CNAs) were identified in 98% of WDLPS and DDLPS and in 95% of MLPS cases. The minimal common region of amplification at 12q14.1q21.1 was observed in 96% of WDLPS and DDLPS cases. Four regions of CNAs, including losses of chromosome 6, 11 and 13 and gains of chromosome 14 were classified as recurrent in DDLPS; at least one was identified in 74% of DDLPS tumors. The DDLPS-associated losses were much more common in tumors with increased genomic complexity. In MLPS, the most frequent CNAs were losses of chromosome 6 (40%) and gains of chromosome 1 (30%), with the minimal overlapping regions 6q14.1q22.31 and 1q25.1q32.2, respectively. CONCLUSIONS: Our findings show that the application of array-CGH allows to delineate clearly the genomic profiles of WDLPS, DDLPS and MLPS that reflect biological differences between these tumors. Although CNAs varied widely, the subtypes of tumors have characteristic genomic profiles that could facilitate the differential diagnosis of LPS subtypes, especially between WDLPS and DDLPS.

Proteins Involved in HER2 Signalling Pathway, Their Relations and Influence on Metastasis-Free Survival in HER2-Positive Breast Cancer Patients Treated with Trastuzumab in Adjuvant Setting.

AIM: Resistance to trastuzumab (which is a standard therapy for breast cancer patients with HER2 overexpression) is associated with higher risk of progression or cancer death, and might be related to activation of signalling cascades (PI3K/AKT/mTOR, Ras/Raf/MAPK) and decreased level of their inhibitors. MATERIAL AND METHODS: Formalin-fixed paraffin-embedded tumour specimens from 118 HER2-overexpressing breast cancer patients treated with radical local therapy and trastuzumab in adjuvant setting were used for the assessment of: (1) PIK3CA gene mutations (p.H1047R and p.E545K) by qPCR, and (2) expression of Ki-67, EGFR, MUC4, HER3 and PTEN by immunohistochemistry. RESULTS: Lower Ki-67LI was observed in EGFR-immunonegative and in PTEN-immunopositive tumours. MUC4-immunonegative tumours more frequently were PTEN- and HER3-immunonegative. Favourable metastasis-free survival was observed in patients with tumours characterized by Ki-67LI≤50% (p=0.027), HER3 immunonegativity or PTEN immunopositivity (vs. tumours with HER3 expression and lack of PTEN expression, p=0.043), additionally, the trend was observed for patients with pN0+pN1 pathological tumour stage (vs. pN2+pN3) (p=0.086). Cox model revealed that independent negative prognostic factors were: (i) Ki-67LI>50% (p=0.014, RR=4.6, 95% CI 1.4-15.4), (ii) HER3 immunopositivity together with PTEN immunonegativity (p=0.034, RR=3.7, 95% CI 1.1-12.5). CONCLUSION: The results of our study suggest that combined analysis of HER3 and PTEN expression might bring information on trastuzumab sensitivity in the group of HER2-positive breast cancer patients treated with trastuzumab in adjuvant setting.

The role of histology, grading, location of tumour and ploidy in evaluation of outcome in patients with liposarcoma.

Department of Tumour Pathology, Maria Sklodowska-Curie Memorial Cancer Center and Institute of Oncology, Kraków, Poland The review of literature indicates that several clinico-morphological factors such as location of the primary tumour as well as its size, histologic subtype, and grade or even selected molecular changes may significantly affect survival of liposarcoma (LPS) patients. Data concerning prognostic importance of DNA ploidy status in LPS cells are extremely limited and results of flow cytometry (FCM) studies have never been compiled with the current classification of malignant adipocytic tumours. Based on evaluation of material from 54 liposarcomas which was available for both histological and FCM analysis, we distinguished four prognostic groups of patients. The best prognosis was noticed for diploid and grade G1 well-differentiated or myxoid liposarcomas localised on extremities. None of the patients with lipoma-like WDLPS and myxoid liposarcoma grade 1 metastasised, while metastases were observed among patients with dedifferentiated LPS (70% of 5-year MFS) and cellular myxoid or round cell liposarcoma (20% of 5-year MFS, only). The metastasis-free survival curves for the above mentioned groups of patients differed significantly (p = 0.00001).

Signatures of post-zygotic structural genetic aberrations in the cells of histologically normal breast tissue that can predispose to sporadic breast cancer.

Sporadic breast cancer (SBC) is a common disease without robust means of early risk prediction in the population. We studied 282 females with SBC, focusing on copy number aberrations in cancer-free breast tissue (uninvolved margin, UM) outside the primary tumor (PT). In total, 1162 UMs (1-14 per breast) were studied. Comparative analysis between UM(s), PT(s), and blood/skin from the same patient as a control is the core of the study design. We identified 108 patients with at least one aberrant UM, representing 38.3% of cases. Gains in gene copy number were the principal type of mutations in microscopically normal breast cells, suggesting that oncogenic activation of genes via increased gene copy number is a predominant mechanism for initiation of SBC pathogenesis. The gain of ERBB2, with overexpression of HER2 protein, was the most common aberration in normal cells. Five additional growth factor receptor genes (EGFR, FGFR1, IGF1R, LIFR, and NGFR) also showed recurrent gains, and these were occasionally present in combination with the gain of ERBB2. All the aberrations found in the normal breast cells were previously described in cancer literature, suggesting their causative, driving role in pathogenesis of SBC. We demonstrate that analysis of normal cells from cancer patients leads to identification of signatures that may increase risk of SBC and our results could influence the choice of surgical intervention to remove all predisposing cells. Early detection of copy number gains suggesting a predisposition toward cancer development, long before detectable tumors are formed, is a key to the anticipated shift into a preventive paradigm of personalized medicine for breast cancer.

Prognostic value of PIK3CA mutation status, PTEN and androgen receptor expression for metastasis-free survival in HER2-positive breast cancer patients treated with trastuzumab in adjuvant setting.

Resistance to trastuzumab in patients with HER2-overexpressing breast cancer is associated with higher risk of progression or cancer death, and might be related to activation of PI3K/AKT/mTOR and Ras/Raf/MAPK signaling cascades and a decreased level of their inhibitor (PTEN). HER2-overexpressing breast cancer patients (n=75) treated with radical local therapy and trastuzumab in adjuvant setting were included into the study. Deoxyribonucleic acid isolated from paraffin sections was used to assess mutational status of the PIK3CA gene (p.H1047R and p.E545K mutations) by the quantitative polymerase chain reaction technique. Expression of selected proteins (ER, PgR, AR, Ki-67, EGFR) was assessed using immunohistochemistry. In the studied group we found significantly higher Ki-67LI in EGFR-positive carcinomas (p=0.048). Moreover, EGFR immunonegativity was observed more frequently in low-grade (G1/G2) carcinomas as well as in estrogen/progesterone and androgen receptor immunopositive tumors (p=0.042, p=0.016, p=0.044, respectively). Favorable metastasis-free survival was observed in patients with pN0 and pN1 (vs. pN2+3) stage (p=0.040) and with tumors characterized by low Ki-67LI (≤50% vs. >50%) (p=0.014). Patients with tumor androgen receptor immunonegativity (weak or lack of expression) or strong PTEN expression survived 3 years without metastases (p=0.007). The results of our study suggest that androgen receptor and PTEN status might be considered as indicators of trastuzumab sensitivity.

Metallothionein-3 Increases Triple-Negative Breast Cancer Cell Invasiveness via Induction of Metalloproteinase Expression.

It has been recently found that metallothionein-3 (MT3) enhances the invasiveness and tumorigenesis of prostate cancer cells. This finding is in contrast to those of earlier studies, which indicated that overexpression of MT3 in breast cancer and prostate cancer cell lines inhibits their growth in vitro. Therefore, to clarify the role of MT3 in breast cancer progression, we analyzed the effect of MT3-overexpression on proliferation, invasiveness, migration, and tumorigenesis of breast cancer MDA-MB-231/BO2 cells. It was found that MDA-MB-231/BO2 cells overexpressing MT3 were characterized by increased invasiveness in vitro, compared to the control cells. Interestingly, this increased invasiveness correlated with a highly increased concentration of MMP3 in the culture supernatants (p<0.0001). Our data suggest that MT3 may regulate breast cancer cell invasiveness by modulating the expression of MMP3. These experimental results, obtained using triple-negative MDA-MB-231/BO2 cells, were further supported by clinical data. It was found that, in triple-negative breast cancer (TNBC), nuclear MT3 immunoreactivity in cancer cells tended to be associated with patients' shorter disease-specific survival, suggesting that nuclear MT3 expression may be a potential marker of poor prognosis of triple-negative TNBC cases.

Histopathological assessment of residual retroperitoneal mass removed in patients after chemotherapy for non-seminomatous germ cell tumours of the testis.

Between 1990 and 1999, 182 men were treated for non-seminomatous germ cell testicular tumours. In 24 of them after chemotherapy a residual retroperitoneal mass was removed. In 14 of them additional immunohistochemical (IHC) examinations using antibodies against cytokeratins, vimentin, PLAP, CD30, AFP, ßhCG, p53, and MIB-1 were performed. We compared the results of those additional studies with the results of routine histopathological examination. Histological assessment revealed most frequently (ca. 54% of cases) non-neoplastic lesions, i.e. fibro-cystic, necrotic or inflammatory tumours and lymphatic tissue. In about 33% of cases, surviving live neoplastic cells were found.

Impact of different tumour stroma assessment methods regarding podoplanin expression on clinical outcome in patients with invasive ductal breast carcinoma.

BACKGROUND: Podoplanin, a small mucin-type transmembrane protein has been shown in several studies to be expressed in cancer-associated fibroblasts (CAFs) and affect patient outcome. MATERIALS AND METHODS: We evaluated podoplanin expression in CAFs in a cohort of 257 patients with invasive ductal breast carcinomas (IDCs) using three different assessment scales based on the number of positive cells alone or in combination with the reaction intensity. RESULTS: Two of the utilized scales yielded prognostic information concerning patients' overall survival (OS), but scores were not independent prognostic factors in the multivariate analysis. On the contrary, two scales based on the combination of cell positivity and reaction intensity had no significant impact on patients' OS, but they were significantly correlated with a greater number of analysed clinicopathological parameters. CONCLUSION: In summary, podoplanin expression in CAFs may be considered a possible marker of poor prognosis in IDC, however, caution should be taken as the results varied regarding the utilized scales.

Specificity and sensitivity of INI-1 labeling in epithelioid sarcoma. Loss of INI1 expression as a frequent immunohistochemical event in synovial sarcoma.

INI1 antigen is a product of the INI-1/SMARCB1 gene localized on chromosome 22q. It is well known that INI1 gene inactivation or loss of INI1 antigen expression is observed in epithelioid sarcomas; however, there are only few reports concerning specificity and sensitivity of immunohistochemical INI1 labeling as a marker of this neoplasm. That is why we decided to test 99 soft tissue sarcomas for the presence of the INI1 gene product. More specifically, the analyzed group consisted of 33 synovial sarcomas, 14 fibrosarcomas, 8 desmoid tumors, 8 DFSPs, 5 MPNSTs, 9 epithelioid sarcomas, 11 Ewing sarcomas/PNETs, 9 rhabdomyosarcomas and 2 clear cell sarcomas. Additionally, 7 malignant melanomas and 9 adenocarcinomas were included into the study. Positive staining with an antibody against the INI-1 gene product was observed in all studied cases of MPNST, Ewing sarcoma/PNET, rhabdomyosarcoma, malignant melanoma, clear cell sarcoma, and adenocarcinoma. On the contrary, none of 9 epithelioid sarcomas was labeled. The loss of INI1 expression was also detected in 7 (21.2%) synovial sarcomas, confirmed cytogenetically or by FISH. Considering the lack of reaction with INI-1 antibody as a diagnostic test for epithelioid sarcoma we estimated that its sensitivity reached 100% and specificity - 83.5% (p < 0.0001).