FOXO3a deregulation in uterine smooth muscle tumors.

OBJECTIVE: The present study aimed to investigate FOXO3a deregulation in Uterine Smooth Muscle Tumors (USMT) and its potential association with cancer development and prognosis. METHODS: The authors analyzed gene and protein expression profiles of FOXO3a in 56 uterine Leiomyosarcomas (LMS), 119 leiomyomas (comprising conventional and unusual leiomyomas), and 20 Myometrium (MM) samples. The authors used techniques such as Immunohistochemistry (IHC), FISH/CISH, and qRT-PCR for the present analyses. Additionally, the authors conducted an in-silico analysis to understand the interaction network involving FOXO3a and its correlated genes. RESULTS: This investigation revealed distinct expression patterns of the FOXO3a gene and protein, including both normal and phosphorylated forms. Expression levels were notably elevated in LMS, and Unusual Leiomyomas (ULM) compared to conventional Leiomyomas (LM) and Myometrium (MM) samples. This upregulation was significantly associated with metastasis and Overall Survival (OS) in LMS patients. Intriguingly, FOXO3a deregulation did not seem to be influenced by EGF/HER-2 signaling, as there were minimal levels of EGF and VEGF expression detected, and HER-2 and EGFR were negative in the analyzed samples. In the examination of miRNAs, the authors observed upregulation of miR-96-5p and miR-155-5p, which are known negative regulators of FOXO3a, in LMS samples. Conversely, the tumor suppressor miR-let7c-5p was downregulated. CONCLUSIONS: In summary, the outcomes of the present study suggest that the imbalance in FOXO3a within Uterine Smooth Muscle Tumors might arise from both protein phosphorylation and miRNA activity. FOXO3a could emerge as a promising therapeutic target for individuals with Unusual Leiomyomas and Leiomyosarcomas (ULM and LMS), offering novel directions for treatment strategies.

POTENTIAL LIFE PROGNOSTIC MARKER FOR MESENCHYMAL TUMOR RESEMBLING UTERINE LEIOMYOSARCOMA.

Benign uterine leiomyoma (U.LMA) and malignant uterine leiomyosarcoma (U.LMS), both uterine mesenchymal tumors, are distinguished by the number of cells exhibiting mitotic activity. However, uterine mesenchymal tumors contain tumor cells with various cell morphologies; therefore, making a diagnosis, including differentiating between benign and malignant tumors, is difficult. For example, cotyledonoid dissecting leiomyoma (CDL) or uterine smooth muscle tumors of uncertain malignant potential (STUMPs) are a group of uterine mesenchymal tumors for which a differential diagnosis is challenging. To date, a standardized classification system for uterine mesenchymal tumors has not yet been established. Furthermore, definitive preoperative imaging techniques or hematological examinations for the potential inclusion of CDL or STUMP in the differential diagnosis have not been defined. Several clinical studies have reported that there is no correlation between biomarker expression and mitotic rate or tumor recurrence. The immunohistochemical biomarkers reported so far cannot effectively help determine the malignant potential of CDL or STUMPs in patients who wish to become pregnant in the future. The establishment of gene expression profiles or detection of pathogenic variants by using next-generation molecular techniques can facilitate disease prediction, diagnosis, treatment, and prognosis. We examined the oncological properties of STUMP in adults using molecular pathological techniques on tissue excised from patients with uterine mesenchymal tumor. In a clinical study conducted by our medical team, the results of gene expression profiling indicated factors that may be associated with malignancy of uterine mesenchymal tumors. We herein describe the problems in diagnosing uterine mesenchymal tumors along with the results of the latest clinical studies. It is expected that the establishment of a diagnostic method targeting the characteristics of mesenchymal tumor cells will lead to the treatment of malignant tumors with a low risk of recurrence and metastasis.

Clinical and Histopathological Predictors of Recurrence in Uterine Smooth Muscle Tumor of Uncertain Malignant Potential (STUMP): A Multicenter Retrospective Cohort Study of Tertiary Centers.

BACKGROUND: The term uterine smooth muscle tumor of uncertain malignant potential (STUMP) indicates a rare, equivocal entity between benign leiomyomas and leiomyosarcomas. In the present study, we evaluated a comprehensive range of clinical, surgical, and pathological features in a large multicenter series of patients with STUMP to identify risk factors for recurrence. METHODS: This is a retrospective study performed by collecting consecutive cases diagnosed between January 2000 and December 2020 in five tertiary centers. Associations between STUMP recurrence and clinicopathological characteristics as well as surgical treatment modality were investigated. RESULTS: Eighty-seven patients affected by STUMP were considered. Of them, 18 cases (20.7%) recurred: 11 as leiomyosarcoma (LMS) and 7 as STUMP. The mean time to recurrence was 79 months. We found that fragmentation/morcellation, epithelioid features, high mitotic count, Ki-67 value > 20%, progesterone receptor (PR) < 83%, and p16 diffuse expression were associated with higher risk of recurrence and shorter recurrence-free survival (RFS). Furthermore, morcellation/fragmentation and mitotic count remained independent risk factors for recurrence and shorter RFS after multivariate analysis, while the presence of epithelioid features was an independent risk factor for recurrence only. CONCLUSIONS: Our results suggest that morcellation is associated with risk of recurrence and shorter RFS, thus it should be avoided if a STUMP is suspected preoperatively. Epithelioid features, high proliferation activity, low PR expression, and diffuse p16 expression are also unfavorable prognostic factors, so patients presenting these features should be closely followed up.

Inherited TNFSF9 deficiency causes broad Epstein-Barr virus infection with EBV+ smooth muscle tumors.

Epstein-Barr virus (EBV) can infect smooth muscle cells causing smooth muscle tumors (SMTs) or leiomyoma. Here, we report a patient with a heterozygous 22q11.2 deletion/DiGeorge syndrome who developed a unique, broad, and lethal susceptibility to EBV characterized by EBV-infected T and B cells and disseminated EBV+SMT. The patient also harbored a homozygous missense mutation (p.V140G) in TNFSF9 coding for CD137L/4-1BBL, the ligand of the T cell co-stimulatory molecule CD137/4-1BB, whose deficiency predisposes to EBV infection. We show that wild-type CD137L was up-regulated on activated monocytes and dendritic cells, EBV-infected B cells, and SMT. The CD137LV140G mutant was weakly expressed on patient cells or when ectopically expressed in HEK and P815 cells. Importantly, patient EBV-infected B cells failed to trigger the expansion of EBV-specific T cells, resulting in decreased T cell effector responses. T cell expansion was recovered when CD137L expression was restored on B cells. Therefore, these results highlight the critical role of the CD137-CD137L pathway in anti-EBV immunity, in particular in the control of EBV+SMT.

CD56 is Expressed in Uterine Smooth Muscle Tumors.

CD56 is used in gynecologic pathology, typically in the context of a neuroendocrine, sex cord or sex cord-like tumor. It has never been studied in uterine smooth muscle tumors, which can potentially enter their differential diagnosis, and thus CD56 positivity could potentially be a pitfall. Thus, the aim of this study was to explore its expression in this category of tumors. Seventy-eight uterine smooth muscle tumors, including 14 leiomyosarcomas, 46 leiomyomas and their variants, 14 smooth muscle tumors of uncertain malignant potential, and 4 intravenous leiomyomatoses were studied in regard to CD56 expression. Fifty-eight nearby myometria were also analyzed. Sixty-five (83.4%) tumors showed CD56 expression. Nearby myometrium showed CD56 expression in 15 cases (25.9%). Staining ranged from 10% to 100% of tumor or myometrial cells (median 80% and 50%, respectively). Among the tumor types, leiomyoma with bizarre nuclei, had the lowest extensive expression (P=0.01). Most uterine smooth muscle neoplasms express CD56; thus, it is not useful in attempting to discriminate from endometrial stromal or sex cord-like neoplasms.

Hereditary leiomyomatosis and renal cell carcinoma syndrome associated uterine smooth muscle tumors: Bridging morphology and clinical screening.

Hereditary leiomyomatosis and renal cell carcinoma (HLRCC) is an autosomal dominant familial syndrome that results from germline mutation in the fumarate hydratase (FH) gene and is associated with an increased risk for smooth muscle tumors of the uterus and skin and renal cell carcinoma. HLRCC associated RCC develop in up to 25% of patients, often presenting in the fourth decade and are high stage, aggressive tumors with poor clinical outcome. Most women with HLRCC develop large and bulky uterine smooth muscle tumors (USMT) in the second to third decade, thus presenting the ideal opportunity for early detection of HLCC to enable timely implementation of surveillance for their RCC risk. However, the concept of screening women with USMT for HLRCC is challenging given that HLRCC is rare but USMT are common. In addition, FH deficiency in USMT can also result from sporadic FH gene aberrations, unrelated to HLRCC, further complicating any potential screening process. Recent studies show that tumor morphology can be used to identify FH deficiency in USMT and thereby direct patients to formal genetic counseling. The low magnification clues of staghorn shaped blood vessels and alveolar pattern should prompt for high magnification examination for eosinophilic cytoplasmic inclusions and oval nuclei containing prominent eosinophilic macronucleoli surrounded by a halo. Additional clues include Schwannoma-like growth and chain-like distribution of the tumor cells. Although immunostains exist for FH and 2SC, their role is limited in the presence of well-developed FH deficient morphology. The prevalence of germline pathogenic mutation in FH among women with USMT with FH deficient morphology is as high as 50% in some studies, with somatic FH mutation accounting for the remainder. Therefore, morphologic evaluation of USMT for features of FH deficiency can serve as a screening tool for HLRCC syndrome by triaging patients to formal hereditary risk assessment.

Cutaneous Epstein-Barr virus-associated smooth muscle tumor in immunosuppression.

A 36-year-old renal transplant recipient presented 15 months post-transplantation with a cutaneous spindle cell neoplasm with features of smooth muscle differentiation treated with local excision. 1.4 years later, a magnetic resonance imaging liver scan with gadolinium demonstrated multiple bilobar enhancing hepatic lesions, in keeping with metastases. A core biopsy revealed morphological appearances similar to the previous cutaneous spindle cell neoplasm. Epstein-Barr virus early RNA (EBER) in situ hybridization demonstrated strong diffuse staining of both cutaneous and liver tumor cells for EBER indicative of Epstein-Barr virus (EBV) infection. This is a rare presentation of multifocal EBV-associated smooth muscle tumors first presenting in the skin in an adult renal transplant recipient, which, despite being multifocal and involving the liver, may confer a better prognosis than predicted.

Recent advances in smooth muscle tumors with PGR and PLAG1 gene fusions and myofibroblastic uterine neoplasms.

Uterine epithelioid and myxoid leiomyosarcomas and inflammatory myofibroblastic tumors are rare mesenchymal neoplasms. Next-generation sequencing recently detected novel PGR fusions in uterine epithelioid leiomyosarcomas that demonstrate characteristic rhabdoid and spindled morphology. PLAG1 gene fusions have also been identified in a subset of myxoid leiomyosarcomas and are associated with PLAG1 overexpression. ALK rearrangements underpin the vast majority of uterine inflammatory myofibroblastic tumors, which demonstrate morphologic, and immunohistochemical features similar to those of inflammatory myofibroblastic tumors elsewhere. This review summarizes the morphologic, immunophenotypic, and molecular genetic features of PGR fusion-positive epithelioid leiomyosarcoma, PLAG1 fusion-positive myxoid leiomyosarcoma, and inflammatory myofibroblastic tumors of the uterus.

Combination of MCM2 With Ki67 and p16 Immunohistochemistry Can Distinguish Uterine Leiomyosarcomas.

Our objective was to evaluate the diagnostic utility of 2 new proliferation markers, cyclin D1 and minichromosome maintenance complex component 2 (MCM2), in comparison with p16, p53, and Ki67 in differentiating the spectrum of smooth muscle tumors. An institutional database search from 2009 to 2017 identified 10 cases of uterine leiomyoma with bizarre nuclei (LBN), 12 smooth muscle tumors of uncertain malignant potential, and 13 leiomyosarcomas (LMS). Ten resected leiomyomas (LM) were included as controls. Immunohistochemistry was performed on the befitting representative block from each case. Ki67 was <10% in all LMs and LBNs, whereas >10% in all LMSs. Although wild-type in majority of cases, p53 was overexpressed in 38% of LMSs. Cyclin D1 nuclear positivity in LMs, LBNs, and smooth muscle tumors of uncertain malignant potentials ranged from 0% to 65% of neoplastic cells with mostly weak to moderate staining intensity. Instead, cyclin D1 expression was <5% in all LMSs. The ratio of MCM2 positivity exhibited a similar wide range (<1%-80%) in LMs, LBNs, and smooth muscle tumors of uncertain malignant potentials but interestingly, 92% (12/13) of LMSs were diffusely and strongly positive for MCM2 (>80% cell positivity). Overall, for diagnosis of LMS, the sensitivity for diffuse intense MCM2 staining was higher (92%) compared with diffuse staining for p16 (77%); however, specificity of MCM2 and p16 was comparable (94% and 97%, respectively). Herein, we describe the immunohistochemical profile of 2 new proliferation markers, cyclin D1 and MCM2 in uterine smooth muscle tumors. A combination of diffuse strong MCM2 and p16 reactivity with increased Ki67 index can reliably distinguish LMSs from benign histologic mimics.

Differential expression, diagnostic and prognostic significance of stathmin-1 and CD147 in various uterine smooth muscle tumors / Expresión diferencial, diagnóstico y significado de pronóstico de stathmin-1 y CD147 en diferentes tumores del músculo liso uterino

SUMMARY: Uterine smooth muscle tumors (USMT) are common, behavior-distinct gynecological tumors; including: leiomyoma (ULM), leiomyosarcoma (ULMS), and smooth muscle tumors of undetermined malignant potential (STUMP). Pre-operative distinction is difficult, thus diagnosis relies on histopathology. Immunohistochemistry (IHC) had been used to help in distinction. We studied two markers (stathmin-1 and CD147) to demonstrate whether they have diagnostic/ prognostic assist. Sixty seven USMT are studied. Age, follow up, and recurrence/metastasis data were collected. Representative slides were stained and Histologic score (HS) calculated as stain intensity (SI) X percentage of positive tumor cells (PP). Results were grouped as low expression (LE) and high expression (HE); then correlated to tumor types, and risk of recurrence/ metastasis. Statistical analysis (P < 0.05); Sensitivity, specificity, positive and negative predictive values and confidence intervals in diagnosing ULMS were calculated. Stathmin-1 HS (p= 0.000) and HE (p=0.002) were different among groups. Same as for CD147 HS and HE (both p=0.000), with a gradient increase from LM to STUMP to ULMS. Sensitivity, specificity, positive and negative predictive values and confidence intervals in diagnosing ULMS were as following: For stathmin-1 HS: 92 %; 20 %; 42 %; and 80 % (CI= 44-96 %). For Stathmin-1 HE: 80 %; 66 %; 60 %; and 84 % (CI=66-94 %). For CD147 HS: 85 %; 22 %; 41 %; and 69 %. For CD147 HE: 58 %; 49 %; 42 %; and 65 % (CI= 45-80 %), respectively. Recurrence / metastasis were documented in 6 cases (4 ULMS; 2 STUMP) with follow up ranging from 6 months to 102 months. 5 tumors had stathmin-1 HE (p=0.099); 2 had CD147 HE (p=0.393) in the primary tumors. STMN1 and CD147 are helpful diagnostic tests for USMT sub-typing, especially for ULMS. Gradient increase of expression from LM, to STUMP, to ULMS may indicate a role in malignant transformation in USMT, and in increased risk of recurrences/metastasis.

RESUMEN: Los tumores del músculo liso uterino (USMT, por sus siglas en inglés) son tumores ginecológicos comunes y de comportamiento distinto; incluyendo: leiomioma (ULM), leiomiosarcoma (ULMS) y tumores de músculo liso de potencial maligno indeterminado (STUMP). La distinción preoperatoria es difícil, por lo que el diagnóstico se basa en la histopatología. La inmunohistoquímica (IHQ) se había utilizado para ayudar en la distinción. Estudiamos dos marcadores (stathmin-1 y CD147) para demostrar si había efecto diagnóstico / pronóstico. Se estudiaron 67 USMT. Se recopilaron los datos de edad, seguimiento y recurrencia / metástasis. Las muestras representativas se tiñeron y la puntuación histológica (HS) se calculó como la intensidad de la tinción (IS) x porcentaje de células tumorales positivas (PP). Los resultados se agruparon como expresión baja (EB) y expresión alta (EA); luego se correlacionaeon con los tipos de tumores y el riesgo de recurrencia / metástasis. Análisis estadístico (P <0,05); se calcularon la sensibilidad, la especificidad, los valores predictivos positivos y negativos y los intervalos de confianza en el diagnóstico de ULMS. Stathmin-1 HS (p = 0,000) y HE (p = 0,002) fueron diferentes entre los grupos. Igual que para CD147 HS y HE (ambos p = 0,000), con un aumento de gradiente de LM a STUMP a ULMS. La sensibilidad, la especificidad, los valores predictivos positivos y negativos y los intervalos de confianza en el diagnóstico de ULMS fueron los siguientes: Para stathmin-1 HS: 92 %; 20 %; 42 %; y 80 % (IC = 44-96 %). Para Stathmin-1 HE: 80 %; 66 %; 60 %; y 84 % (IC = 66-94 %). Para CD147 HS: 85 %; 22 %; 41 %; y el 69 %. Para CD147 HE: 58 %; 49 %; 42 %; y 65 % (IC = 45-80 %), respectivamente. La recurrencia / metástasis se documentaron en 6 casos (4 ULMS; 2 STUMP) con un seguimiento que osciló entre 6 meses y 102 meses. Cinco tumores tenían stathmin-1 HE (p = 0,099); dos tenían CD147 HE (p = 0,393) en los tumores primarios. STMN1 y CD147 son pruebas de diagnóstico útiles para la subclasificación de USMT, especialmente para ULMS. El aumento en el gradiente de la expresión de LM, a STUMP, a ULMS puede indicar un papel en la transformación maligna en USMT y en un mayor riesgo de recurrencias / metástasis.

An estrogen receptor-positive locally aggressive smooth muscle neoplasm of the transverse colon: A case report.

RATIONALE: Extrauterine leiomyomas (LMs) in women are often positive for the estrogen receptor (ER); however, almost all extrauterine leiomyosarcomas (LMSs) are negative for ER. Invasive smooth muscle neoplasms (SMNs) of the gastrointestinal tract walls are very rare and those ER statuses have not been well studied. PATIENT CONCERNS: A 48-year-old woman presented to our hospital with a 10 years history of recurrent severe abdominal pain and diarrhea lasting about an hour, with frequency of about twice per year. She was clinically diagnosed with a submucosal tumor (SMT) of the transverse colon and underwent a partial transverse colectomy. DIAGNOSIS: A colonoscopy revealed a 30-mm SMT in the transverse colon. A contrast abdominal computed tomography detected a 21-mm mass with significant late phase enhancement in the transverse colon and the lesion was clinically diagnosed as an SMT. Post-operative pathology confirmed a diagnosis of ER-positive locally aggressive SMN. INTERVENTIONS: The patient underwent laparoscopic partial transverse colectomy. OUTCOMES: The patient received no adjuvant therapy postoperatively. The patient has remained disease-free without recurrence 13 months after the surgery. LESSONS: This is the first case of an ER-positive invasive SMN in the gastrointestinal tract. It highlights the difficulty in classifying some gastrointestinal SMNs as either LMs or LMSs and the importance of ER status in SMNs.

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.

Immunoexpression of progesterone receptor, epithelial growth factor receptor and galectin-3 in uterine smooth muscle tumors.

Uterine smooth muscle tumors constitute a spectrum of neoplasms. Diagnosis of leiomyomas (LMs) is usually straight forwards; however, atypical leiomyomas (ALMs) and smooth muscle tumors of uncertain malignant potential (STUMPs) have overlapping features and need to be distinguished from leiomyosarcoma. To evaluate progesterone receptor (PR), epithelial growth factor receptor (EGF-R), and galectin-3 expression in LMs, ALMs, STUMPs, and leiomyosarcomas and to assess their possible role in differentiating those tumors. Immunoexpression of EGF-R, PR, and galectin-3 were studied in 44 cases of uterine smooth muscle tumors through retrospective study. Studied cases included 20 LM, 9 ALM, 5 STUMP, and 10 leiomyosarcomas. A semiquantitative score was used to evaluate immunohistochemical staining. EGF-R overexpression was detected in leiomyosarcomas while a lack of or reduced EGF-R expression was observed in the nonsarcomatous group (LMs, ALMs, and STUMPs) with a highly significant difference. On the contrary, there was weak or negative PR staining in leiomyosarcomas compared to intense PR expression in the nonsarcomatous group with a highly significant difference. Meanwhile, galectin-3 was downregulated in leiomyosarcomas compared to the nonsarcomatous group with a significant difference. Correlation analysis revealed negative correlation between EGF-R and PR expression with significant statistical results while correlation of galectin-3 with EGF-R and PR showed insignificant statistical results. Immunoexpression of EGF-R, PR, and galectin-3 could help differentiate challenging cases of uterine smooth muscle tumors. Further studies are recommended to investigate interactions between EGF-R, PR, and galectin-3 and to plan new therapeutic strategies.

The Clinicopathological Study of 21 Cases With Uterine Smooth Muscle Tumors of Uncertain Malignant Potential: Centralized Review Can Purify the Diagnosis.

OBJECTIVE: The objective of this study was to investigate the clinicopathological features and factors associated with recurrence in patients with uterine smooth muscle tumor of uncertain malignant potential (STUMP). METHODS: Forty-six cases diagnosed between 2000 and 2014 from 2 tertiary centers underwent blind slide review. Initial diagnosis included smooth muscle tumors with equivocal diagnosis, STUMPs, and cases that were named as leiomyosarcomas (LMS) or low-grade LMS despite not fulfilling the Stanford criteria. RESULTS: In total, 21 patients with a final diagnosis of STUMP were available. Fifteen (68.1%) of 22 patients with an initial diagnosis of STUMP, 4 (22.2%) of 18 cases with an equivocal smooth muscle tumor diagnosis, and 2 (33.3%) of 6 cases with an initial diagnosis of LMS were interpreted as STUMP after slide review. The mean age at diagnosis was 43 years (range, 20-64 years). The mean follow-up time was 65.9 months (range, 10-154 months). Four patients (19.0%) developed recurrent disease. Recurrent tumors were LMS in 3 patients (75%). One patient (4.8%) with recurrence succumbed to disease. There was no difference in patients' age (P = 1.0) or type of initial surgery (uterus conserving versus hysterectomy) (P = 0.57) between patients who recurred and did not recur. CONCLUSIONS: Uterine STUMPs can harbor significant uncertainty regarding the original diagnosis and clinical outcomes. Recurred cases may have an aggressive clinical course associated with multiple relapses and death. Uterine mesenchymal tumors other than ordinary myomas and overt sarcomas deserve a second opinion in centers with experience because the real diagnosis may vary significantly.

Atypical Uterine Smooth Muscle Tumors: A Retrospective Evaluation of Clinical and Pathologic Features.

BACKGROUND: Clinical characteristics combined with new biomarkers help discriminate between atypical uterine smooth muscle tumors (AUSMT) and leiomyosarcomas (LMS). PATIENTS AND METHODS: We retrospectively collected a series of leiomyomas (LM), AUSMT, and LMS. Estrogen receptors (ER), progesterone receptors (PR), p16, Ki-67, and p53 expression were assessed by immunohistochemistry. For AUSMT patients, immunohistochemistry evaluations were performed at the time of diagnosis and at recurrences. RESULTS: A total of 27 cases of AUSMT, 22 LM, and 31 LMS were identified. The expression of ER and PR decreased from LM to LMS (ER+: LM 95.5%, AUSMT 88.9%, LMS 41.9%, p < 0.001; PR+: LM 100%, AUSMT 88.9%, LMS 38.2%, p = 0.002). By contrast, p16 and p53 expression increased (p16+: LM 4.5%, AUSMT 40.7%, LMS 45.2%, p = 0.004; p53: LM 9.1%, AUSMT 33.3%, LMS 58.1%, p = 0.001). At a median follow-up of 33.47 months, 40.7% of patients with AUSMT experienced recurrent disease, 6 patients relapsed as AUSMT and 5 as LMS. In univariate analysis was observed that ER status (p = 0.027) and p53 expression (p = 0.015) predicted risk of relapse. CONCLUSIONS: Treatment of AUSMT should be centralized in dedicated centers. International collaborations are needed to optimize research strategy, which may lead to the identification of new useful biomarkers and to improvement in the clinical management of this rare disease.

Characterization of MED12, HMGA2, and FH alterations reveals molecular variability in uterine smooth muscle tumors.

Uterine smooth muscle tumors range from benign leiomyomas to malignant leiomyosarcomas. Based on numerous molecular studies, leiomyomas and leiomyosarcomas mostly lack shared mutations and the majority of tumors are believed to develop through distinct mechanisms. To further characterize the molecular variability among uterine smooth muscle tumors, and simultaneously insinuate their potential malignant progression, we examined the frequency of known genetic leiomyoma driver alterations (MED12 mutations, HMGA2 overexpression, biallelic FH inactivation) in 65 conventional leiomyomas, 94 histopathological leiomyoma variants (18 leiomyomas with bizarre nuclei, 22 cellular, 29 highly cellular, and 25 mitotically active leiomyomas), and 51 leiomyosarcomas. Of the 210 tumors analyzed, 107 had mutations in one of the three driver genes. No tumor had more than one mutation confirming that all alterations are mutually exclusive. MED12 mutations were the most common alterations in conventional and mitotically active leiomyomas and leiomyosarcomas, while leiomyomas with bizarre nuclei were most often FH deficient and cellular tumors showed frequent HMGA2 overexpression. Highly cellular leiomyomas displayed the least amount of alterations leaving the majority of tumors with no known driver aberration. Our results indicate that based on the molecular background, histopathological leiomyoma subtypes do not only differ from conventional leiomyomas, but also from each other. The presence of leiomyoma driver alterations in nearly one third of leiomyosarcomas suggests that some tumors arise through leiomyoma precursor lesion or that these mutations provide growth advantage also to highly aggressive cancers. It is clinically relevant to understand the molecular background of various smooth muscle tumor subtypes, as it may lead to improved diagnosis and personalized treatments in the future.

Is differential expression of p16INK4a based on the classification of uterine smooth muscle tumors associated with a different prognosis? A meta-analysis.

We conducted a meta-analysis to examine p16INK4a expression in uterine smooth muscle tumors (USMTs). Although the prognostic value of tumor suppressor p16INK4a has been elucidated in a variety of cancers and precancerous lesions, its role in USMTs is not well established. We searched PubMed, Web of Science, and Embase for publication son p16INK4a expression in USMTs. Strict inclusion and exclusion criteria were imposed. Risk ratios (RRs) with 95% confidence intervals (95%CIs) were calculated to assess the strength of association. Publication bias was estimated using funnel plots and the Egger's regression test. Twelve eligible studies comprising 661 patients were included. Compared with leiomyoma (LM), the figures for the strength of association were as follows: LM variants (RR = 1.53, 95%CI = 1.03-2.27, P = 0.036, random effect); leiomyosarcoma (LMS) (RR = 3.20, 95%CI = 1.68-6.12, P < 0.001, random effect); and smooth muscle tumors of uncertain malignant potential (STUMP) (RR = 2.90, 95%CI = 1.17-7.21, P = 0.022, random effect). p16INK4a expression was significantly higher in LMS than in LM variants (RR = 3.74, 95%CI = 1.96-7.13, P < 0.001, random effect) or STUMP (RR = 1.67, 95%CI = 1.26-2.23, P < 0.001, fixed effect). There was a significant correlation between overexpressed p16INK4a and recurrence rates of USMTs (RR = 1.85, 95%CI = 1.11-3.10, P = 0.019, fixed effect). p16INK4a over expression is a potential biomarker for diagnosing problematic USMTs and it might indicate a worse prognosis. However, there is currently insufficient evidence to assess the prognostic value of p16INK4a in USMTs.

Mixed endometrial stromal and smooth muscle tumor of the uterus in a postmenopausal woman: morphologic and immunohistochemical features.

Mixed endometrial stromal and smooth muscle tumor of the uterus is a rare occurrence, and it is truly challenging to diagnose or dif- ferentiate mesenchymal tumors of the uterine corpus, due to their many overlapping features. In most cases, the gross pathology of mixed endometrial stromal and smooth muscle tumor differs from that of pure endometrial stromal and pure smooth muscle tumors. A 59-year-old postmenopausal woman presented with vaginal spotting, low abdominal pain, and an uterine mass. Subsequent pelvic magnetic resonance imaging revealed a 4.0x3.8x3.4-cm sized uterine mass with enhancement. The mass showed restricted diffusion on diffusion-weighted images, and thus, was suspected to be uterine sarcoma rather than degenerative leiomyoma. Levels of tumor markers, CA 125, CA 19-9, and SCC, were within their normal ranges. The patient underwent exploratory laparotomy. Morphological and immunohistochemical evaluations were performed, and a final diagnosis of mixed endometrial stromal and smooth muscle tumor of the uterus was rendered. Her postoperative course was uneventful, and aromatase inhibitor adjuvant therapy was administered.

TOP2A copy number and TOP2A expression in uterine benign smooth muscle tumours and leiomyosarcoma.

AIMS: To examine TOP2A copy number, TOP2A expression, and its prognostic value in uterine leiomyosarcoma (LMS) and other benign smooth muscle tumours. METHODS: We analysed 37 patients treated for uterine LMS with immunohistochemistry for protein expression and fluorescence in situ hybridisation (FISH) for copy number. Twelve cases of leiomyoma variants (LMVs), 4 smooth muscle tumours of uncertain malignant potential (STUMP) and 23 leiomyomas (LMs) were also included. RESULTS: Eighteen patients with LMS (48.6%) were International Federation of Gynecology and Obstetrics (FIGO) stage I, six (16.2%) were stage II, four (10.8%) were stage III, and nine (24.3%) were stage IV. Twenty-one (56.8%) patients with LMS showed high expression of TOP2A. Greater TOP2A levels were found in patients with stage ≥II disease compared with stage I and also in high mitotic index tumours (>20/10 HPF (high power field)). Eleven (36.7%) cases had abnormal TOP2A copy numbers. There was no link between TOP2A copy number and TOP2A expression. All patients with benign smooth muscle tumours had low TOP2A immunohistochemical expression and one (7.7%) patient had TOP2A amplification. TOP2A expression and TOP2A copy number had no impact on disease outcomes. Only the presence of disease outside of the uterus negatively impacted survival compared with early disease (53.4 vs 15.8 months; p<0.001). CONCLUSIONS: TOP2A is highly expressed in advanced LMS but not in non-malignant diseases. TOP2A expression does not correlate with FISH results and does not predict outcome. TOP2A levels are higher in high-mitotic index tumours and in more advanced stages of disease.

EMMPRIN (CD147) Expression in Smooth Muscle Tumors of the Uterus.

Smooth muscle tumors of the uterus are the most common mesenchymal tumors of the gynecologic tract. The vast majority of these are benign leiomyomas that present no diagnostic difficulty. Because some benign smooth muscle tumors may degenerate and uncommon variants exist, the diagnosis can be challenging in some cases. The goal of this research was to investigate EMMPRIN expression in leiomyomas, leiomyoma variants, and leiomyosarcomas (LMS) to determine whether it has a potential role in differential diagnosis. EMMPRIN expression was investigated with immunohistochemistry in 103 uterine smooth muscle tumors, which included 19 usual leiomyomas, 52 leiomyoma variants, and 32 LMS. They were evaluated on the basis of staining extent, intensity, and also their combined score, and the groups were compared. EMMPRIN expression was present in 3 of 19 (15.7%) usual leiomyomas, 23 of 52 (44.3%) leiomyoma variants, and 28 of 32 (87.5%) LMS. There were statistically significant differences in staining extent and intensity, and also for their combined scores, between the LMS and benign groups. Although uterine smooth muscle tumors are usually diagnosed easily with conventional diagnostic criteria, the differentiation of LMS from some variants of leiomyoma can be challenging based soley on morphology. EMMPRIN may be a valuable immunohistochemical marker for differentiating LMS from benign smooth muscle tumors in problematic cases.