Immunohistochemical Analysis for Therapeutic Targets and Prognostic Markers in Low-Grade Endometrial Stromal Sarcoma

Prognostic Value of Ki-67 Index in Patients With Endometrial Stromal Sarcoma

Objective

The Ki-67 index is used to evaluate cell proliferation activity, which is related to tumor progression, metastasis, and prognosis. We aimed to explore the prognostic value of Ki-67 index in endometrial stromal sarcoma and to explore the optimal cut-off value of Ki-67 index for predicting recurrent endometrial stromal sarcoma.

Methods

A total of 82 patients with endometrial stromal sarcoma who were treated in our hospital were collected. Clinicopathological data of these patients were retrospectively analyzed. Ki-67 index was detected by the immunohistochemical method. Receiver operating characteristic curve and the Youden index were performed to determine the optimal cut-off value of Ki-67 index for predicting recurrent endometrial stromal sarcoma. The Cox regression was performed to analyze risk factors affecting prognosis of endometrial stromal sarcoma. The Kaplan–Meier method and Log-rank test were performed to analyze the survival of patients.

Results

The optimal cut-off value of Ki-67 index for predicting recurrent endometrial stromal sarcoma was 35%. The results of univariate analysis showed that high Ki-67 index (≥35%) was statistically significantly bound up with shorter progress free survival and overall survival. The results of multivariate analysis showed that Ki-67 index (P = 0.001) and ovarian preservation (P = 0.040) were independent prognostic factors of progress free survival.

Conclusions

A Ki-67 index cut-off of 35% was optimal for predicting recurrent endometrial stromal sarcoma. Ki-67 index may be a useful prognostic marker in endometrial stromal sarcoma.

Candidate Biomarkers for Specific Intraoperative Near-Infrared Imaging of Soft Tissue Sarcomas: A Systematic Review

Simple Summary

Near-infrared imaging of tumors during surgery facilitates the oncologic surgeon to distinguish malignant from healthy tissue. The technique is based on fluorescent tracers binding to tumor biomarkers on malignant cells. Currently, there are no clinically available fluorescent tracers that specifically target soft tissue sarcomas. This review searched the literature to find candidate biomarkers for soft tissue sarcomas, based on clinically used therapeutic antibodies. The search revealed 7 biomarkers: TEM1, VEGFR-1, EGFR, VEGFR-2, IGF-1R, PDGFRα, and CD40. These biomarkers are abundantly present on soft tissue sarcoma tumor cells and are already being targeted with humanized monoclonal antibodies. The conjugation of these antibodies with a fluorescent dye will yield in specific tracers for image-guided surgery of soft tissue sarcomas to improve the success rates of tumor resections.

Abstract

Surgery is the mainstay of treatment for localized soft tissue sarcomas (STS). The curative treatment highly depends on complete tumor resection, as positive margins are associated with local recurrence (LR) and prognosis. However, determining the tumor margin during surgery is challenging. Real-time tumor-specific imaging can facilitate complete resection by visualizing tumor tissue during surgery. Unfortunately, STS specific tracers are presently not clinically available. In this review, STS-associated cell surface-expressed biomarkers, which are currently already clinically targeted with monoclonal antibodies for therapeutic purposes, are evaluated for their use in near-infrared fluorescence (NIRF) imaging of STS. Clinically targeted biomarkers in STS were extracted from clinical trial registers and a PubMed search was performed. Data on biomarker characteristics, sample size, percentage of biomarker-positive STS samples, pattern of biomarker expression, biomarker internalization features, and previous applications of the biomarker in imaging were extracted. The biomarkers were ranked utilizing a previously described scoring system. Eleven cell surface-expressed biomarkers were identified from which 7 were selected as potential biomarkers for NIRF imaging: TEM1, VEGFR-1, EGFR, VEGFR-2, IGF-1R, PDGFRα, and CD40. Promising biomarkers in common and aggressive STS subtypes are TEM1 for myxofibrosarcoma, TEM1, and PDGFRα for undifferentiated soft tissue sarcoma and EGFR for synovial sarcoma.

[Interdisciplinary S2k guidelines on the diagnosis and treatment of uterine sarcomas-recommendations for surgical pathology]

Uterine sarcomas represent a heterogeneous group of rare malignancies, derived from the myometrium, the endometrial stroma, and very rarely from the nonspecialized uterine soft tissue. The actual incidence is about 1.5 for Caucasian and 3.0 for Afro-American women. There is no grading system for leimoysarcoma defined by the WHO classification; however, if clinicians request, the FNCLCC grading can be specified in analogy to soft tissue sarcomas. Adenosarcomas must be distinguished from adenofibromas (the existence of which is questionable)-with the vast majority of these tumors being uterine adenosarcomas. Within adenosarcomas, deep myometrial invasion (>50%), sarcomatous overgrowth, and a high-grade heterologous component are associated with a higher recurrence rate and poor survival. The immunohistochemical panel represents a very helpful tool for distinguishing low-grade from high grade endometrial stromal sarcomas (ESS) and may be supplemented by molecular analyses. Steroid hormone receptor analysis should be performed for all ESS due to the possible therapeutic relevance. Undifferentiated uterine sarcomas represent a diagnosis of exclusion and have a very poor prognosis. Carcinosarcomas represent a special subtype of endometrial carcinomas and are in fact not uterine sarcomas. Uterine sarcomas may present substantial intratumoral heterogeneity and adequate embedding is mandatory. Lesions ≤2 cm in the largest dimension should be processed completely and larger tumors should be processed with one block per centimeter for the largest tumor dimension.

OSucs: An Online Prognostic Biomarker Analysis Tool for Uterine Carcinosarcoma

BACKGROUND

Uterine carcinosarcoma (UCS) is a type of rare and aggressive tumor. The standard treatment for UCS involves surgical treatment followed by radiochemotherapy. Clinical outcomes of UCS patients are poor due to high metastasis and relapse rate. Therefore, new targeted therapy strategies for UCS are needed. Because UCS is highly heterogenous, it is critical to identify and develop prognostic biomarkers to distinguish molecular subtypes of UCS for better treatment guidance.

METHODS

Using gene expression profiles and clinical follow-up data, we developed an online consensus survival analysis tool named OSucs. This web tool allows researchers to conveniently analyze the prognostic abilities of candidate genes in UCS.

RESULTS

To test the reliability of this server, we analyzed five previously reported prognostic biomarkers, all of which showed significant prognostic impacts. In addition, ETV4 (ETS variant transcription factor 4), ANGPTL4 (Angiopoietin-like protein 4), HIST1H1C (Histone cluster 1 H1 family member c) and CTSV (Cathepsin V) showed prognostic potential in a molecular subtype-specific manner.

CONCLUSION

We built a platform for researchers to analyze if genes have prognostic potentials in UCS.

Low-Grade Endometrial Stromal Sarcoma - a Review

Like other uterine sarcomas, low-grade endometrial stromal sarcomas (LG-ESS) are a very rare tumor entity. In the past, research studies therefore discussed the various different types of the disease in combination. In addition, the classification of endometrial stromal tumors presented difficulties for quite some time so that in earlier studies it was not always possible to precisely distinguish between LG-ESS, high-grade endometrial stromal sarcoma, and undifferentiated uterine sarcoma. For LG-ESS, surgery with hysterectomy and adnexectomy is the first-line treatment. The benefits of lymphadenectomy and tumor debulking are unclear. Endocrine therapy with gestagens and aromatase inhibitors is under discussion to provide adjuvant treatment for patients with advanced stages of the disease. As radiotherapy only provides locoregional control, and in view of the usually good prognosis of patients with LG-ESS, its benefits need to be weighed against its side effects. In the case of recurrence, repeat surgery is the first choice. Further research studies viewing LG-ESS as a distinct entity are needed in order to improve treatment options for patients with LG-ESS.

Overexpressed genes in malignant pleural mesothelioma: implications in clinical management

Malignant pleural mesothelioma (MPM) is a very aggressive cancer poorly responsive to current therapies. MPM patients have a very poor prognosis with a median survival of less than one year from the onset of symptoms. The biomarkers proposed so far do not lead to a sufficiently early diagnosis for a radical treatment of the disease. Thus, the finding of novel diagnostic and prognostic biomarkers and therapeutic targets is needed. Gene overexpression has been frequently associated with a malignant phenotype in several cancer types; therefore the identification of overexpressed genes may lead to the detection of novel prognostic or diagnostic marker and to the development of novel therapeutic approaches, based on their inhibition. In the last years, several overexpressed genes have been identified in MPM through gene expression profiling techniques: among them it has been found a group of 51 genes that resulted overexpressed in more than one independent study, revealing their consistency among studies. This article reviews the clinical implications of confirmed overexpressed genes in MPM described so far in literature.

Immunohistochemistry in Gynecologic Pathology: An Example-Based Practical Update

CONTEXT

- Immunohistochemical stains are routinely applied in the pathology diagnostic workup of gynecologic lesions. The rapidly expanding repertoire of available markers helps in refining the diagnostic criteria for each disease entity; however, limitations and pitfalls exist.

OBJECTIVE

- To provide a practical, relevant update on the use of immunohistochemistry for commonly encountered differential diagnoses in gynecologic pathology.

DATA SOURCES

- Literature review and authors' diagnostic experience.

CONCLUSIONS

- Immunohistochemistry is a helpful adjunct tool in gynecologic pathology. Although the primary application is in the diagnostic workup, novel prognostic and predictive markers, and immunostains to screen for genetic cancer syndromes, have also been recently introduced in the field.

Potential Therapeutic Targets in Uterine Sarcomas

Uterine sarcomas are rare tumors accounting for 3,4% of all uterine cancers. Even after radical hysterectomy, most patients relapse or present with distant metastases. The very limited clinical benefit of adjuvant cytotoxic treatments is reflected by high mortality rates, emphasizing the need for new treatment strategies. This review summarizes rising potential targets in four distinct subtypes of uterine sarcomas: leiomyosarcoma, low-grade and high-grade endometrial stromal sarcoma, and undifferentiated uterine sarcoma. Based on clinical reports, promising approaches for uterine leiomyosarcoma patients include inhibition of VEGF and mTOR signaling, preferably in combination with other targeted or cytotoxic compounds. Currently, the only targeted therapy approved in leiomyosarcoma patients is pazopanib, a multitargeted inhibitor blocking VEGFR, PDGFR, FGFR, and c-KIT. Additionally, preclinical evidence suggests effect of the inhibition of histone deacetylases, tyrosine kinase receptors, and the mitotic checkpoint protein aurora kinase A. In low-grade endometrial stromal sarcomas, antihormonal therapies including aromatase inhibitors and progestins have proven activity. Other potential targets are PDGFR, VEGFR, and histone deacetylases. In high-grade ESS that carry the YWHAE/FAM22A/B fusion gene, the generated 14-3-3 oncoprotein is a putative target, next to c-KIT and the Wnt pathway. The observation of heterogeneity within uterine sarcoma subtypes warrants a personalized treatment approach.

Ki67 is a promising molecular target in the diagnosis of cancer (review)

The expression of Ki67 is strongly associated with tumor cell proliferation and growth, and is widely used in routine pathological investigation as a proliferation marker. The nuclear protein Ki67 (pKi67) is an established prognostic and predictive indicator for the assessment of biopsies from patients with cancer. Clinically, pKi67 has been shown to correlate with metastasis and the clinical stage of tumors. In addition, it has been shown that Ki67 expression is significantly higher malignant tissues with poorly differentiated tumor cells, as compared with normal tissue. According to its predictive role, pKi67 expression identifies subpopulations of patients who are more likely to respond to a given therapy. The Ki67 labeling index is an independent prognostic factor for survival rate, which includes all stages and grade categories. There is a correlation between the ratio of Ki67‑positive malignant cells and patient survival. It has been shown that blocking of Ki67 either by microinjection of antibodies or through the use of antisense oligonucleotides leads to the arrest of cell proliferation. Specifically, antisense oligonucleotides and antibodies against pKi67 have been shown to inhibit the progression of the cell cycle. The Ki67 protein is well characterized at the molecular level and is extensively used as a prognostic and predictive marker for cancer diagnosis and treatment. Increasing evidence indicates that Ki67 may be an effective target in cancer therapy. It therefore merits further development, including testing in more sophisticated in vitro and appropriate in vivo models. This review provides an overview of recent advances in this field.

Endometrial stromal tumors: the new WHO classification

Endometrial stromal tumors are rare uterine mesenchymal neoplasms that have intrigued pathologists for years, not only because they commonly pose diagnostic dilemmas, but also because the classification and pathogenesis of these tumors has been widely debated. The current World Health Organization recognizes 4 categories of endometrial stromal tumor: endometrial stromal nodule (ESN), low-grade endometrial stromal sarcoma (LG-ESS), high-grade endometrial stromal sarcoma (HG-ESS), and undifferentiated uterine sarcoma (UUS). uterine sarcoma. These categories are defined by the presence of distinct translocations as well as tumor morphology and prognosis. Specifically, the JAZF1-SUZ12 (formerly JAZF1-JJAZ1) fusion identifies a large proportion of ESN and LG-ESSs, whereas the YWHAE-FAM22 translocation identifies HG-ESSs. The latter tumors appear to have a prognosis intermediate between LG-ESS and UUS, which exhibits no specific translocation pattern. This review (1) presents the clinicopathologic features of endometrial stromal tumors; (2) discusses their immunophenotype; and (3) highlights the recent advances in molecular genetics which explain their pathogenesis and lend support for a new classification system.

Molecular mechanisms of endometrial stromal sarcoma and undifferentiated endometrial sarcoma as premises for new therapeutic strategies

Endometrial stromal sarcoma (ESS) and undifferentiated endometrial sarcoma (UES) are very rare gynecologic malignancies. Due to the rarity and heterogeneity of these tumors, little is known about their epidemiology, pathogenesis, and molecular pathology. Our previous studies have described deregulation of histone deacetylases expression in ESS/UES samples. Some of these enzymes can be inhibited by substances which are already approved for treatment of cutaneous T-cell lymphoma. On the basis of published data, they may also provide a therapeutic option for ESS/UES patients. Our review focuses on molecular mechanisms of ESS/UES. It describes various aspects with special emphasis on alteration of histone deacetylation and its possible relevance for novel therapies.

Frequent expression of KIT in endometrial stromal sarcoma with YWHAE genetic rearrangement

Endometrial stromal sarcomas with the YWHAE-NUTM2A/B genetic fusion characteristically contain high-grade round to epithelioid cell component that is strongly and diffusely cyclin D1-positive and it may or may not show an associated low-grade fibroblastic/myxoid cell component. They are clinically more aggressive than endometrial stromal sarcomas with the JAZF1-SUZ12 genetic fusion and frequently demonstrate extrauterine extension at initial clinical presentation. In this setting, the tumor may be misdiagnosed as gastrointestinal stromal tumor. This study examines the expression of KIT and ANO1 in 14 YWHAE-NUTM2A/B tumors by immunohistochemistry. Staining localization was determined as membranous and/or cytoplasmic, and the staining intensity was assessed (negative, weak, moderate and strong). Of the 14 tumors, 6 contained only a high-grade round cell component, 2 only a low-grade fibroblastic component and 6 had both components in the slides evaluated. The high-grade round cell component displayed moderate to strong membranous/cytoplasmic KIT staining in all tumors (12 of 12). The low-grade fibroblastic cell component showed only weak cytoplasmic KIT staining in 3 of 8 tumors. In contrast, ANO1 was negative in all 14 neoplasms, irrespective of the component evaluated. Sanger sequencing analysis (exons 9, 11, 13 and 17) and Ampliseq Cancer Panel mutation screen (Ion Torrent) demonstrated no KIT mutations in three KIT-positive YWHAE-NUTM2A/B tumors. This study shows that the high-grade round cell component of YWHAE-NUTM2A/B endometrial stromal sarcoma consistently expresses KIT but lacks KIT hotspot mutations. KIT expression may represent a potential diagnostic pitfall in the evaluation of YWHAE-NUTM2A/B endometrial stromal sarcoma presenting with pelvic/abdominal mass, particularly in situations where its uterine origin is not definitive, and thus a panel of antibodies that includes ANO1 and cyclin D1 is necessary.

The long non-coding RNA HOTAIR is upregulated in endometrial carcinoma and correlates with poor prognosis

Long non-coding RNAs (lncRNAs) are emerging as key molecules in human cancer. Homeobox (HOX) transcript antisense intergenic RNA (HOTAIR), a long non-coding RNA (lncRNA), is associated with a variety of human cancers, such as breast, liver and lung cancer. However, whether HOTAIR can function as a molecular marker in endometrial carcinoma (EC) remains unknown. In the present study, the expression of HOTAIR in 66 EC tissues from patients with EC and 30 normal tissues from healthy age-matched control subjects was determined using quantitative reverse transcription PCR. Furthermore, using in situ hybridization, we measured HOTAIR expression in 129 formalin-fixed paraffin-embedded (FFPE) tissue sections, which included 96 tissues that matched the frozen cases, 21 other EC tissues and 12 atypical hyperplasia tissues. Correlations between HOTAIR expression and the clinicopathological characteristics of patients were analyzed. Our results revealed that HOTAIR expression in the EC tissues was significantly upregulated compared with normal tissues (p<0.001). In addition, we observed a significant association between HOTAIR expression and the EC grade (p<0.05) and lymph node metastasis (p<0.05). Moreover, in the FFPE tissues, but not the frozen tissues, we found that a higher HOTAIR expression also correlated with the depth of myometrial invasion (p=0.019) and lymphovascular space invasion (p=0.015). More importantly, patients with a higher HOTAIR expression showed significantly poorer overall survival than those with lower HOTAIR expression (p<0.05). In conclusion, our results suggest that a high expression of HOTAIR is involved in the progression of cancer and may be a novel biomarker of poor prognosis in patients with EC.

Can proliferation biomarkers reliably predict recurrence in World Health Organization 2003 defined endometrial stromal sarcoma, low grade?

An estimated 1500–3000 invasive Endometrial Stromal Sarcomas (ESS) cases annually occur worldwide. Before 2003, ESS was divided as low and high grade ESS based on mitotic activity. In 2003 the WHO changed the names, excluded mitoses and made nuclear atypia and necrosis the essential diagnostic criteria to distinguish ESS, Low Grade (ESS-LG, recurrence-free survival >90%) and Undifferentiated Endometrial Sarcoma (UES, poor prognosis). We have evaluated in WHO2003 defined ESS-LG whether proliferation biomarkers predict recurrence. Using survival analysis, the prognostic value of classical mitosis counts (Mitotic Activity Index, MAI) in haematoxyllin-eosin (H&E) sections, and immunohistochemical proliferation biomarkers (Ki-67 and PhosphoHistone-3 (PPH3)) were examined in 24 invasive endometrial stromal sarcomas. Three of 24 (12.5%) ESS-LG recurred. The MAI, PPH3 and Ki-67 were all prognostic (P = 0.001, 0.002 and 0.03). MAI values were >3 in the recurrent cases, but never exceeded 10 (the classical threshold for low and high grade). Non-recurrent cases had 0≤MAI≤3. PPH3 and Ki67 counts can be easier to perform than MAI and therefore helpful in the diagnosis of ESS, Low Grade. In conclusion, in this small study of WHO2003 defined ESS-LG, high levels of proliferation as measured by MAI, PPH3 and Ki-67 are predictive of recurrence. Larger studies are required to confirm these results.

Endometrial stromal tumors: immunohistochemical and molecular analysis of potential targets of tyrosine kinase inhibitors

BACKGROUND

The systemic treatment of malignant endometrial stromal tumors (EST) is not well established. A few reports describe objective responses to imatinib, which suggest a novel therapeutic strategy for these tumors. Due to these facts, we aimed to perform a retrospective analysis of possible molecular targets of tyrosine kinase inhibitors (TKI) in EST: KIT, PDGFRA and EGFR.

METHODS

52 endometrial stromal sarcomas and 13 undifferentiated endometrial sarcomas were examined and reviewed. Mutational analysis were performed for exons 9, 11, 13, and 17 of the KIT gene, exons 12 and 18 of the PDGFRA gene and exons 18, 19, 20 and 21 of the EGFR gene. The incidence and distribution of the KIT, PDGFRA, and EGFR expression were examined by immunohistochemistry, and EGFR amplification was assessed by fluorescence in situ hybridization.

RESULTS

No mutations in KIT, PDGFRA and EGFR genes were detected. Overexpression of KIT, PDGFRA, EGFR, was detected in 2 (3%), 23 (35.4%), 7 (10.8%) cases respectively, whereas amplification of EGFR gene was not found.

CONCLUSIONS

Absence of significant expression, amplification and activating mutations on these tyrosine kinase receptors suggest that it is unlikely that EST can benefit from therapies such as TKI on the systemic setting.