Analysis of fumarate hydratase mutations in a population-based series of early onset uterine leiomyosarcoma patients

Genomic profile analysis of leiomyomas with bizarre nuclei and fumarate hydratase deficient leiomyomas: Strengths, weaknesses, and limitations of array-CGH interpretation

A close relationship has been demonstrated between genomic complexity and clinical outcome in uterine smooth muscle tumors. We studied the genomic profiles by array-CGH of 28 fumarate hydratase deficient leiomyomas and 37 leiomyomas with bizarre nuclei (LMBN) from 64 patients. Follow-up was available for 46 patients (from three to 249 months, mean 87.3 months). All patients were alive without evidence of disease. For 51 array-CGH interpretable tumors the mean Genomic Index (GI) was 16.4 (median: 9.8; from 1 to 57.8), significantly lower than the mean GI in LMS (mean GI 51.8, p < 0.001). We described three groups: (1) a group with FH deletion (24/58) with low GI (mean GI: 11 vs. 22,4, p = 0.02), (2) a group with TP53 deletion (17/58) with higher GI (22.4 vs. 11 p = 0.02), and (3) a group without genomic events on FH or TP53 genes (17/58) (mean GI:18.3; from 1 to 57.8). Because none of these tumors recurred and none showed morphological features of LMS we concluded that GI at the cut-off of 10 was not applicable in these subtypes of LM. By integration of all those findings, a GI <10 in LMBN remains a valuable argument for benignity. Conversely, in LMBN a GI >10 or alteration in tumor suppressor genes, should not alone warrant a diagnosis of malignancy. Nine tumors were tested with Nanocind CINSARC® signature and all were classified in low risk of recurrence. We propose, based on our observations, a diagnostic approach of these challenging lesions.

Hereditary leiomyomatosis and renal cell cancer (HLRCC) syndrome in a young patient presenting with a large uterus: A case report and review of the literature

Hereditary leiomyomatosis and renal cell cancer (HLRCC) syndrome is a rare genetic disorder caused by a germline mutation in the fumarate hydratase (FH) gene. It is clinically characterized by cutaneous leiomyomas, uterine leiomyomas and renal cell cancer. A 31-year-old woman presented with severe abdominopelvic pain associated with severe menorrhagia which required a visit to the emergency department. Computed tomography (CT) showed a severe enlargement of the uterus with newly diagnosed fibroids. Magnetic resonance imaging (MRI) confirmed the finding of an enlarged uterus with mild left and moderate right hydronephrosis and hydroureter. The patient tried to manage the pain with oral over-the-counter medications and heat pads without significant relief. She was recommended to proceed with total abdominal hysterectomy and bilateral salpingectomy. She tolerated the procedure well and had an uneventful postoperative recovery. Pathology showed morphologic features, including the staghorn vessels, alveolar edema, eosinophilic cytoplasmic inclusions and prominent nucleoli which are characteristics for FH-deficient leiomyomas. Genetic testing was positive for a pathogenic variant in the FH gene associated with HLRCC. This case highlights the importance of proceeding with genetic testing in patients with personal and family history of leiomyomas and unusual pathology findings. Early identification of the syndrome can lead to appropriate screening for renal cell carcinoma.

Fumarate Hydratase and S-(2-Succinyl)-Cysteine Immunohistochemistry Shows Evidence of Fumarate Hydratase Deficiency in 2% of Uterine Leiomyosarcomas: A Cohort Study of 348 Tumors

Approximately 1% to 1.5% of uterine leiomyomas are fumarate hydratase (FH)-deficient (FHd). A subset of these are associated with germline FH mutations. However, the prevalence and clinicopathologic characteristics of FHd uterine leiomyosarcoma (uLMS) remain unknown. Clinicopathologic data were collected for 348 uLMS. Morphologic features associated with FH deficiency (staghorn-type vessels, alveolar-pattern edema, macronucleoli with perinucleolar clearing, eosinophilic cytoplasmic inclusions, and chain-like nuclear arrangement) were documented. All 348 tumors were studied by FH immunohistochemistry. Eighty-nine were also studied by S-(2-succinyl)-cysteine (2SC) immunohistochemistry. Seven (2%) FHd uLMS were identified. Five showed uniformly negative FH and diffusely positive 2SC immunostaining; 1 showed variably negative to weak to strong FH and diffusely positive 2SC immunostaining; and 1 showed retained FH staining alongside positive 2SC confined to a morphologically distinct subclone. Three of 7 patients had extrauterine disease at presentation, and 3 of 6 had persistent disease or died from disease. Macronucleoli with perinucleolar clearing were significantly more common in FHd uLMS (7/7) than in uLMS with retained FH (182/341; P =0.017). Disease-specific survival, disease-free survival, and other morphologic features of FH deficiency did not differ significantly between FHd and FH-retained tumors. Our data emphasize that immunohistochemical FH deficiency does not preclude malignancy in uterine smooth muscle tumors. However, the biological significance and molecular basis of FH deficiency in uLMS, including any relationship to germline FH mutation, remain unknown, and a larger multi-institutional effort is necessary to gather sufficient FHd uLMS for more robustly powered clinicopathologic and for molecular characterization.

Fumarate Hydratase Deficiency Should be Considered in the Differential Diagnosis of Uterine and Extrauterine Smooth Muscle Tumors of Uncertain Malignant Potential (STUMP)

Fumarate hydratase-deficient leiomyomas (dFH leiomyomas) often display atypical pathologic features yet exhibit a benign clinical course. Recent data suggest that dFH leiomyomas may be misclassified as smooth muscle tumors of uncertain malignant potential, a category that encompasses a heterogenous subgroup of uterine neoplasms with smooth muscle differentiation and atypical features that impart ambiguity regarding their expected clinical behavior. dFH leiomyomas can be seen in the context of hereditary leiomyomatosis and renal cell carcinoma syndrome or in the sporadic setting. In this retrospective study, we sought to examine the prevalence and clinicopathologic characteristics of dFH leiomyomas in 48 tumors previously diagnosed as smooth muscle tumors of uncertain malignant potential from 38 patients. Of these 48 tumors, 3 (6.3%) occurring in 2 patients were found to be deficient for FH by immunohistochemistry, including 1 uterine and 2 extrauterine (abdominopelvic) tumors. The 3 tumors showed histologic features typical of dFH leiomyomas, including hemangiopericytoma-like vessels, edema, macronucleoli, and atypia. Neither patient developed recurrent leiomyomas or renal cell carcinoma, and both were alive without disease at last follow-up. Our data suggest that dFH leiomyomas should be considered in the differential diagnosis of smooth muscle tumors of uncertain malignant potential, even in the context of extrauterine disease. Identification of FH deficiency in these tumors supports their classification as dFH leiomyomas despite their atypical morphologic features and/or clinical presentation. Importantly, detection of dFH in these cases may identify women at increased risk for hereditary leiomyomatosis and renal cell carcinoma who would benefit from genetic counseling and consideration for FH germline testing.

Uterine leiomyosarcoma: a rare clinical entity

Leiomyosarcoma is a rare aggressive malignant mesenchymal tumour, accounting for 1% of all uterine malignancies. It spreads rapidly through the intraperitoneal and haematogenous pathways. It is often diagnosed postoperatively following myomectomy, hysterectomy or supracervical hysterectomy for presumed benign disease. It has a predilection for perimenopausal women with a median age of 50 years. Individuals may describe symptoms of vaginal or abdominal pressure. Physical examination may reveal a large palpable pelvic mass, which may haemorrhage. Surgery remains the mainstay of treatment. Hysterectomy and a bilateral salpingo-oophorectomy may be considered, depending on the individual's menopausal status. Ovarian preservation can be considered in young patients. Adjuvant systemic treatment and radiotherapy are of no benefit. Gemcitabine/docetaxel and doxorubicin have shown benefit in the treatment of advanced or recurrent disease. The authors present the case of a 44-year-old woman with lower abdominal pain, vaginal bleeding and a uterine fibroid. Laboratory investigations confirmed a leucocytosis, neutrophilia and a thrombocythaemia. Further investigation with an MRI pelvis showed a very large, heterogeneous, malignant appearing pelvic mass compressing the right ureter and it appeared uterine in nature. Her staging CT showed multiple lung metastases. The diagnosis of uterine leiomyosarcoma was subsequently established. Due to the aggressive behaviour of this sarcoma subtype, novel early detection strategies and targeted therapies are required.

Hereditary leiomyomatosis and renal cell cancer syndrome - case report and review of the literature

Hereditary leiomyomatosis and renal cell cancer syndrome (HLRCC) is an exceptionally rare autosomal dominant condition caused by a germline heterozygous mutation of the fumarate hydratase gene. It manifests as multiple piloleiomyomas, associated with numerous, early-onset uterine leiomyomas in female patients, as well as a highly increased risk of renal cell carcinoma (RCC), most often type 2 papillary RCC. HLRCC has been described in association with adrenal cortical hyperplasia, pheochromocytoma, adrenal cortical carcinoma, and other solid tumors, but the exact relationship between these disorders has not yet been clarified. We present a case of HLRCC associated with bilateral adrenal cortical hyperplasia and discuss the pathogenesis, clinical and paraclinical features of HLRCC, as well as the adequate management of these patients.

Hereditary leiomyomatosis and renal cell carcinoma syndrome-associated renal cell carcinoma: Morphological appraisal with a comprehensive review of differential diagnoses

Hereditary leiomyomatosis and renal cell carcinoma (HLRCC) is an autosomal dominant syndrome wherein affected individuals are at risk for the development of cutaneous leiomyomas, early-onset multiple uterine leiomyomas, and an aggressive subtype of renal cell cancer. HLRCC is caused by germline mutations in the fumarate hydratase (FH) gene, which inactivates the enzyme and alters the function of the tricarboxylic acid/Krebs cycle. This article reviews the hitherto described morphologic features of HLRCC-associated renal cell carcinoma (RCC) and outlines the differential diagnosis and ancillary use of immunohistochemistry and molecular diagnostics for these tumors. The morphologic spectrum of HLRCC-associated RCC is wide and histologic features, including tumor cells with prominent nucleoli, perinucleolar halos, and multiple architectural patterns within the same tumor, which are suggestive of this diagnosis. FH immunohistochemistry in conjunction with genetic counseling and germline FH testing are the important parameters for detection of this entity. These kidney tumors warrant prompt treatment as even smaller sized lesions can demonstrate aggressive behavior and systemic oncologic treatment in metastatic disease should, if possible, be part of a clinical trial. Screening procedures in HLRCC families should preferably be evaluated in large cohorts.

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.

Molecular differential diagnosis of uterine leiomyomas and leiomyosarcomas

Uterine leiomyomas (LM) and leiomyosarcomas (LMS) are considered biologically unrelated tumors due to their cytogenetic and molecular disparity. Yet, these tumors share morphological and molecular characteristics that cannot be differentiated through current clinical diagnostic tests, and thus cannot be definitively classified as benign or malignant until surgery. Newer approaches are needed for the identification of these tumors, as has been done for other tissues. The application of next generation sequencing enables the detection of new mutations that, when coupled to machine learning bioinformatic tools, advances our understanding of chromosomal instability. These approaches in the context of LM and LMS could allow the discovery of genetic variants and possible genomic markers. Additionally, the potential clinical utility of circulating cell-free tumor DNA could revolutionize the noninvasive detection and monitoring of these tumors. Here, we seek to provide a perspective on the molecular background of LM and LMS, recognizing their distinct molecular features that may lead to improved diagnosis and personalized treatments, which would have a measurable impact on women's reproductive health.

Emerging therapeutic approaches for canine sarcomas: Pushing the boundaries beyond the conventional

Sarcomas represent a group of genomically chaotic, highly heterogenous tumours of mesenchymal origin with variable mutational load. Conventional therapy with surgery and radiation therapy is effective for managing small, low-grade sarcomas and remains the standard therapeutic approach. For advanced, high-grade, recurrent, or metastatic sarcomas, systemic chemotherapy provides minimal benefit, therefore, there is a drive to develop novel approaches. The discovery of "Coley's toxins" in the 19th century, and their use to stimulate the immune system supported the application of unconventional therapies for the treatment of sarcomas. While promising, this initial work was abandoned and treatment paradigm and disease course of sarcomas was largely unchanged for several decades. Exciting new therapies are currently changing treatment algorithms for advanced carcinomas and melanomas, and similar approaches are being applied to advance the field of sarcoma research. Recent discoveries in subtype-specific cancer biology and the identification of distinct molecular targets have led to the development of promising targeted strategies with remarkable potential to change the landscape of sarcoma therapy in dogs. The purpose of this review article is to describe the current standard of care and limitations as well as emerging approaches for sarcoma therapy that span many of the most active paradigms in oncologic research, including immunotherapies, checkpoint inhibitors, and drugs capable of cellular metabolic reprogramming.

Liquid Biopsy as a Tool for Differentiation of Leiomyomas and Sarcomas of Corpus Uteri

Utilization of liquid biopsy in the management of cancerous diseases is becoming more attractive. This method can overcome typical limitations of tissue biopsies, especially invasiveness, no repeatability, and the inability to monitor responses to medication during treatment as well as condition during follow-up. Liquid biopsy also provides greater possibility of early prediction of cancer presence. Corpus uteri mesenchymal tumors are comprised of benign variants, which are mostly leiomyomas, but also a heterogenous group of malignant sarcomas. Pre-surgical differentiation between these tumors is very difficult and the final description of tumor characteristics usually requires excision and histological examination. The leiomyomas and malignant leiomyosarcomas are especially difficult to distinguish and can, therefore, be easily misdiagnosed. Because of the very aggressive character of sarcomas, liquid biopsy based on early diagnosis and differentiation of these tumors would be extremely helpful. Moreover, after excision of the tumor, liquid biopsy can contribute to an increased knowledge of sarcoma behavior at the molecular level, especially on the formation of metastases which is still not well understood. In this review, we summarize the most important knowledge of mesenchymal uterine tumors, the possibilities and benefits of liquid biopsy utilization, the types of molecules and cells that can be analyzed with this approach, and the possibility of their isolation and capture. Finally, we review the typical abnormalities of leiomyomas and sarcomas that can be searched and analyzed in liquid biopsy samples with the final aim to pre-surgically differentiate between benign and malignant mesenchymal tumors.

Hereditary Leiomyomatosis and Renal Cell Carcinoma Syndrome (HLRCC): A Contemporary Review and Practical Discussion of the Differential Diagnosis for HLRCC-Associated Renal Cell Carcinoma

CONTEXT.—

Hereditary leiomyomatosis and renal cell carcinoma syndrome (HLRCC) is an uncommon disorder with germline-inactivating mutations in the fumarate hydratase ( FH) gene. The kidney cancers that develop in patients with HLRCC are often unilateral and solitary, with a potentially aggressive clinical course; morphologic identification of suspicious cases is of the utmost importance.

OBJECTIVE.—

To review classic morphologic features of HLRCC-associated renal cell carcinoma, the reported morphologic spectrum of these tumors and their mimics, and the evidence for use of immunohistochemistry and molecular testing in diagnosis of these tumors.

DATA SOURCES.—

University of Michigan cases and review of pertinent literature about HLRCC and the morphologic spectrum of HLRCC-associated renal cell carcinoma.

CONCLUSIONS.—

Histologic features, such as prominent nucleoli with perinucleolar halos and multiple architectural patterns within one tumor, are suggestive of HLRCC-associated renal cell carcinoma. However, the morphologic spectrum is broad. Appropriate use of FH immunohistochemistry and referral to genetic counseling is important for detection of this syndrome.

Uterine sarcomas

Uterine sarcomas account for approximately 3%-7% of all uterine cancers. Since carcinosarcomas are currently classified as metaplastic carcinomas, leiomyosarcomas remain the most common subtype. Exclusion of several histologic variants of leiomyoma, as well as atypical smooth muscle tumors (so-called "smooth muscle tumors of uncertain malignant potential"), has highlighted that the vast majority of leiomyosarcomas are high-grade tumors associated with poor prognosis even when apparently confined to the uterus. Low-grade endometrial stromal sarcomas are indolent tumors associated with long-term survival. High-grade endometrial stromal sarcomas and undifferentiated endometrial sarcomas behave more aggressively than tumors showing nuclear uniformity. Adenosarcomas have a favorable prognosis except for tumors showing myometrial invasion or sarcomatous overgrowth. The prognosis for carcinosarcomas (which are considered here in a postscript fashion) is usually worse than that for grade 3 endometrial carcinomas. Tumor stage is the single most important prognostic factor for uterine sarcomas.

Fumarate Hydratase Mutations and Alterations in Leiomyoma With Bizarre Nuclei

Leiomyoma with bizarre nuclei (LM-BN), is a variant of uterine smooth muscle tumor with atypical histologic features. Although some LM-BN share several significant genetic alterations with leiomyosarcoma, including p16 and p53, the underlying tumorigenesis of LM-BN remains largely unknown. As we previously reported, LM-BN can be divided into 2 subtypes, type I and type II, based on different nuclear features. Type I LM-BN have similar histologic features as uterine smooth muscle tumors with fumarate hydratase (FH) alterations. In this study, we examined FH expression and FH mutations in 77 LM-BN (40 type I cases and 37 type II cases). FH expression was examined by immunohistochemistry using S-(2-succino)-cysteine antibodies (2SC, a protein modification associated with FH inactivation and subsequent fumarate accumulation) and FH antibodies (FH gene products). Seventy-two LM-BN tumors underwent Sanger sequencing to detect FH mutations. We found that 51% (39/77) of LM-BN showed FH alterations detected by immunohistochemistry with both 2SC and FH. Mutational analysis showed that 21% (15/72) of LM-BN harbored FH gene mutations. Further analysis revealed that 85% (34/40) of those with FH alterations were type I LM-BN while 19% (7/37) were type II LM-BN. Our findings suggest that over half of histologically diagnosed LM-BN may be related to FH alterations or FH mutations and the majority of these have the characteristic histologic features of type I LM-BN.

Uterine leiomyosarcoma: A review of the literature and update on management options

Uterine leiomyosarcoma is the most common type of uterine sarcoma. It is an extremely aggressive malignancy associated with a poor overall prognosis. Women affected may vary in age, but are most often diagnosed in their perimenopausal years. Presenting symptoms may be vague and mimic other benign uterine conditions. Preoperative diagnosis of leiomyosarcoma is difficult and often only made at time of surgical resection. These rare mesenchymal tumors are characterized by cytologic atypia, a high mitotic index, and tumor necrosis on histologic inspection. Management of early stage disease entails hysterectomy and complete surgical resection of gross tumor, though routine oophorectomy or lymph node dissection do not appear to confer much clinical benefit. Adjuvant therapy for early stage disease remains controversial as multiple clinical trials have failed to demonstrate benefit on overall survival. Recently, progress has been made in regards to therapy for advanced and recurrent disease. Novel chemotherapeutics, targeted therapies such as olaratumab and pazopanib, and new immunotherapies such as nivolumab and pembrolizumab have demonstrated promise in these previously difficult drug-resistant patients. In this article, we provide a detailed review of uterine leiomyosarcoma including epidemiology, clinical presentation, diagnosis, and pathologic characteristics. We then go on detail management strategies, including options for adjuvant therapy, and highlight new and developing regimens in the field.

An Unusual Presentation of a Cervical Paraspinal Leiomyoma in an Adolescent Female

Objective We describe an apparently unique case of an extra-uterine leiomyoma in the cervical paraspinal tissue including its evaluation and management. Methods A 14-year-old girl was referred to the neurology clinic for an abnormal head CT following a concussion. MRI revealed a homogenously enhancing left cervical paraspinal mass. The patient underwent complete resection and subsequent genetic testing and counseling were obtained to determine the presence of Li-Fraumeni Syndrome (LFS) or Hereditary Leiomyomatosis and Renal Cell Cancer (HLRCC) mutations. Result Histopathological examination proved that the tumor was a benign leiomyoma. Genomic testing for Fumarate Hydratase Gene, HLRCC, TP53 mutations or deletions, and LFS sequencing were negative. Further testing showed no immunosuppression. Conclusions To the best of our knowledge, this is the only case of paraspinal leiomyoma to have been reported to date. We emphasize the importance of considering immunosuppression, LFS, or HLRCC as an underlying cause in extra-uterine leiomyata.

Hereditary leiomyomatosis and renal cell cancer: Cutaneous lesions & atypical fibroids

Objective

To report a diagnosis of hereditary leiomyomatosis and renal cell cancer (HLRCC) syndrome following initial presentation with multiple cutaneous lesions.

Design

Case report.

Design classification

N/A.

Setting

Academic tertiary care center.

Patient(s)

27-year-old nulligravid woman who presented with multiple red-brown lesions on her skin found to have cutaneous and uterine leiomyoma.

Intervention(s)

Biopsy of cutaneous lesions and fertility sparing robot-assisted laparoscopic myomectomy (RALM).

Main outcome measures(s)

Histological assessment of uterine leiomyoma.

Results(s)

Pathologic examination of uterine leiomyoma revealed diffuse atypia and fumarate hydratase loss phenotype concerning for genetic syndrome. Follow-up DNA sequencing via Sanger sequencing confirmed a pathogenetic R2333H mutation consistent with HLRCC.

Conclusion(s)

Consideration of HLRCC on differential diagnosis when patients present with cutaneous nodules and atypical or early onset uterine leiomyoma provides opportunity for early surveillance, family member testing, and more thoughtful surgical planning.

Precis

27-year-old woman with multiple cutaneous lesions is found to have uterine leiomyomas and undergoes robotic myomectomy. Genetic testing of uterine leiomyomas reveals mutation in fumarate hydratase, etiologic in hereditary leiomyomatosis and renal cell cancer (HLRCC).

•

Atypical skin findings and fibroids warrant consideration of HLRCC on the differential diagnosis.

•

Consider similar genetic testing and management as those with Lynch syndrome associated endometrial cancer.

•

Pre-operative planning should take HLRCC into consideration when considering tissue containment and removal strategies.

Uterine Mesenchymal Tumors: Hereditary Aspects

The topic of hereditary gynecologic malignancies readily evokes associations between Lynch syndrome and endometrial adenocarcinoma, or between BRCA mutations and tubo-ovarian serous carcinoma, but other familial associations are less well-known. Two hereditary syndromes are known to be related to uterine mesenchymal tumors: hereditary leiomyomatosis and renal cell carcinoma syndrome and the tuberous sclerosis complex. In the following review, we describe the current literature on these syndromes, summarizing their clinical, morphologic, immunophenotypic, and genetic data. It is possible that the surgical pathologic diagnosis is the first indication of a familial syndrome, thus emphasizing the importance of a pathologist's familiarity with these potentially suggestive lesions.

Oncogenic HrasG12V expression plus knockdown of Cdkn2a using ecotropic lentiviral vectors induces high-grade endometrial stromal sarcoma

The uterine corpus represents the most common site for tumour development in the female genital system. Uterine neoplasms are categorised as epithelial, mesenchymal, mixed epithelial-mesenchymal or trophoblastic tumours. In this study we employed a mouse genetic approach using the MuLE lentiviral gene regulatory system to functionally test the ability of ecotropic lentiviruses to model epithelial and mesenchymal uterine malignancies ex vivo and in vivo. We discovered that MuLE lentiviruses efficiently infect uterine stromal cells but not endometrial epithelial cells when injected into the uterus of cycling, pseudopregnant or ovarectomized mice. Consistent with this cellular infection spectrum, we show that intra-uterine injection of ecotropic MuLE viruses expressing oncogenic HrasG12V together with knockdown of Cdkn2a induce high-grade endometrial stromal sarcomas. These findings establish this approach as an efficient method of generating autochthonous mouse models of uterine sarcomas and in general for performing genetic manipulations of uterine stromal cells in vivo.

Hereditary leiomyomatosis and renal cell cancer syndrome: An update and review

Hereditary leiomyomatosis and renal cell cancer (HLRCC) syndrome is a rare genetic disorder that predisposes individuals to multiple cutaneous leiomyomas, renal cell carcinomas, and in women, uterine leiomyomas. Also known as Reed syndrome, it is caused by a germline heterozygous mutation of the fumarate hydratase tumor suppressor gene. HLRCC is associated with significant morbidity because of pain from cutaneous and uterine leiomyomas, the cutaneous pain often of unique character. Although genetic testing is currently considered the criterion standard to diagnose HLRCC, newer immunohistochemistry markers may provide rapid and cost effective alternatives to genetic testing. Because of the potentially aggressive nature of renal cell carcinomas that develop as early as in childhood, close annual cancer surveillance is desirable in individuals with HLRCC. In this review, we offer an update and an approach to the diagnosis, management, and renal cancer surveillance in HLRCC.

Atypical Leiomyoma With Features Suggesting of Fumarate Hydratase Mutation

Individuals with germ line or somatic mutations of fumarate hydratase are predisposed to the development of leiomyomas of the skin and uterus. In this case report, we will describe the uterine smooth muscle tumors in a young patient who was originally diagnosed with ALM from a myomectomy specimen and experienced recurrence many years later. Tumor cells are diffusely immunoreactive for 2SC, suggestive of FH mutations.

Fumarate Hydratase-deficient Uterine Leiomyomas Occur in Both the Syndromic and Sporadic Settings

Hereditary leiomyomatosis and renal cell carcinoma (HLRCC) syndrome secondary to germline fumarate hydratase (FH) mutation presents with cutaneous and uterine leiomyomas, and a distinctive aggressive renal carcinoma. Identification of HLRCC patients presenting first with uterine leiomyomas may allow early intervention for renal carcinoma. We reviewed the morphology and immunohistochemical (IHC) findings in patients with uterine leiomyomas and confirmed or presumed HLRCC. IHC was also performed on a tissue microarray of unselected uterine leiomyomas and leiomyosarcomas. FH-deficient leiomyomas underwent Sanger and massively parallel sequencing on formalin-fixed paraffin-embedded tissue. All 5 patients with HLRCC had at least 1 FH-deficient leiomyoma: defined as completely negative FH staining with positive internal controls. One percent (12/1152) of unselected uterine leiomyomas but 0 of 88 leiomyosarcomas were FH deficient. FH-deficient leiomyoma patients were younger (42.7 vs. 48.8 y, P=0.024) and commonly demonstrated a distinctive hemangiopericytomatous vasculature. Other features reported to be associated with FH-deficient leiomyomas (hypercellularity, nuclear atypia, inclusion-like nucleoli, stromal edema) were inconstantly present. Somatic FH mutations were identified in 6 of 10 informative unselected FH-deficient leiomyomas. None of these mutations were found in the germline. We conclude that, while the great majority of patients with HLRCC will have FH-deficient leiomyomas, 1% of all uterine leiomyomas are FH deficient usually due to somatic inactivation. Although IHC screening for FH may have a role in confirming patients at high risk for hereditary disease before genetic testing, prospective identification of FH-deficient leiomyomas is of limited clinical benefit in screening unselected patients because of the relatively high incidence of somatic mutations.

Sarcomas Associated With Genetic Cancer Predisposition Syndromes: A Review

: Sarcomas are rare mesenchymal malignancies that demonstrate great clinical and biological heterogeneity. A variety of sarcomas develop in the context of well-defined heritable cancer predisposition syndromes, associations that are often overlooked, given the rarity and diversity of sarcomas and the equivalent relative infrequency of cancer genetic syndromes. This review describes in detail selected heritable cancer predisposition syndromes that are known to be associated with sarcomas. Beyond the molecular and clinical features that define each syndrome, disparities in clinical presentation, natural history, and treatment of syndrome-associated compared with otherwise histologically identical sporadic sarcomas will be described. The clinical approach to selected sarcoma subsets with a view to identifying possible associations with these syndromes will then be described. Although the treatment of the majority of sarcomas will not differ significantly between sporadic cases and those associated with predisposition syndromes, knowledge of features such as unique anatomic sites of affliction or excess toxicities with particular cytotoxic therapies can facilitate alterations in therapeutic strategies to maximize efficacy and minimize toxicity. In addition, recognition of cancer genetic predisposition syndrome will allow patients and their relatives to undertake appropriate genetic counseling and testing, as well as screening, surveillance, and interventional measures, as needed. Situating sarcomas within the genetic endowment of particular patients-specifically that which confers a higher risk of malignancy-will enable clinicians to better manage the patient as a whole, complementing the great efforts currently routinely undertaken to genomically characterize somatic tumor changes with a view to achieving the dream of personalized medicine.

IMPLICATIONS FOR PRACTICE

Sarcomas are uncommon malignancies that often occur sporadically but can also arise in the setting of a recognized heritable cancer predisposition syndrome. Identification of such associations when present can facilitate refinement and optimization of treatment strategies for the sarcoma so as to minimize toxicity and maximize efficacy. Discerning genetic predisposition can also facilitate institution of genetic counseling, as well as screening or surveillance schema for both the patient and his or her relatives, if required. Vigilance for these syndromes has the potential to significantly enhance the quality and comprehensiveness of sarcoma clinical management.

Current Chemotherapy and Potential New Targets in Uterine Leiomyosarcoma

A variety of chemotherapeutic agents have been used for treating recurrent or advanced stage uterine leiomyosarcoma (ULMS). The response rates of these current agents are disappointing, with partial response rates varying from 0% to 33%, and complete response rates varying from 0% to 8%. Recent studies have documented many molecular changes in ULMSs. Prominent amongst these are gains of growth factors C-MYC, Bcl-2, K-ras, and Ki-67, and losses in tumor suppressors p16, p53, Rb1, ING2 and D14S267. Various techniques that have been used to target these molecules are presented. Targeting specific therapies at these underlying molecular changes could potentially yield better response rates with fewer side effects.

Gynecologic Cancer InterGroup (GCIG) consensus review: uterine and ovarian leiomyosarcomas

OBJECTIVES

The Gynecologic Cancer InterGroup aimed to provide an overview of uterine and ovarian leiomyosarcoma management.

METHODS

Published articles and author experience were used to draft management overview. The draft manuscript was circulated to international members of the Gynecologic Cancer InterGroup for review and comment, and appropriate revisions were made.

RESULTS

The approach to management of uterine and ovarian leiomyosarcoma management is reviewed.

CONCLUSIONS

Uterine and ovarian leiomyosarcomas are rare and aggressive cancers that require specialized expertise for optimal management.

Recent advances in understanding and managing leiomyosarcomas

Leiomyosarcomas are malignant mesenchymal tumours that derive from the smooth muscle lineage. They are studied and frequently treated as if they are the same as other soft tissue sarcomas. Recent developments suggest that a different approach may be more appropriate. Their underlying genetic mechanisms remain unclear, and complex. Unbalanced karyotypic defects are the only shared features observed across different leiomyosarcoma subtypes. Unlike other soft tissue sarcomas, leiomyosarcomas are particularly sensitive to the combination of gemcitabine and docetaxel. Furthermore, treatment with trabectedin has shown a good efficacy in leiomyosarcomas, mainly in the form of chronic disease stabilisation.

Mutations in Exon 1 highlight the role of MED12 in uterine leiomyomas

Mediator regulates transcription by connecting gene-specific transcription factors to the RNA polymerase II initiation complex. We recently discovered by exome sequencing that specific exon 2 mutations in mediator complex subunit 12 (MED12) are extremely common in uterine leiomyomas. Subsequent screening studies have focused on this mutational hot spot, and mutations have been detected in uterine leiomyosarcomas, extrauterine leiomyomas and leiomyosarcomas, endometrial polyps, and colorectal cancers. All mutations have been missense changes or in-frame insertions/deletions. Here, we have analyzed 611 samples representing all above-mentioned tumor types for possible exon 1 mutations. Five mutations were observed, all of which were in-frame insertion/deletions in uterine leiomyomas. Transcriptome-wide expression data revealed that MED12 exon 1 and exon 2 mutations lead to the same unique global gene expression pattern with RAD51B being the most upregulated gene. Immunoprecipitation and kinase activity assays showed that both exon 1 and exon 2 mutations disrupt the interaction between MED12 and Cyclin C and CDK8/19 and abolish the mediator-associated CDK kinase activity. These results further emphasize the role of MED12 in uterine leiomyomas, show that exon 1 and exon 2 exert their tumorigenic effect in similar manner, and stress that exon 1 should be included in subsequent MED12 screenings.

Uterine smooth muscle tumors with features suggesting fumarate hydratase aberration: detailed morphologic analysis and correlation with S-(2-succino)-cysteine immunohistochemistry

Rare, sporadic uterine leiomyomas arise in the setting of severe metabolic aberration due to a somatic fumarate hydratase mutation. Germline mutations account for the hereditary leiomyomatosis and renal cell carcinoma syndrome, which predisposes for cutaneous and uterine leiomyomas and aggressive renal cell carcinomas. Altered fumarate hydratase leads to fumarate accumulation in affected cells with formation of S-(2-succino)-cysteine, which can be detected with the polyclonal antibody. High levels of these modified cysteine residues are found characteristically in fumarate hydratase-deficient cells but not in normal tissues or tumors unassociated with hereditary leiomyomatosis and renal cell carcinoma syndrome. We hypothesized that S-(2-succino)-cysteine-positive leiomyomas, indicating fumarate hydratase aberration, have morphologic features that differ from those without S-(2-succino)-cysteine positivity. Hematoxylin and eosin-stained slides of uterine smooth-muscle tumors were prospectively analyzed for features suggesting hereditary leiomyomatosis and renal cell carcinoma syndrome, such as prominent eosinophilic macronucleoli with perinucleolar halos, yielding nine cases. Germline genetic testing for fumarate hydratase mutations was performed in three cases. A detailed morphological analysis was undertaken, and S-(2-succino)-cysteine immunohistochemical analysis was performed with controls from a tissue microarray (leiomyomas (19), leiomyosarcomas (29), and endometrial stromal tumors (15)). Of the nine study cases, four had multiple uterine smooth muscle tumors. All cases had increased cellularity, staghorn vasculature, and fibrillary cytoplasm with pink globules. All cases had inclusion-like nucleoli with perinuclear halos (7 diffuse, 1 focal). All showed diffuse granular cytoplasmic labeling with the S-(2-succino)-cysteine antibody. Two of three tested patients had germline fumarate hydratase mutations. Only one leiomyoma from the tissue microarray controls was immunohistochemically positive, and it showed features similar to other immunohistochemically positive cases. Smooth-muscle tumors with fumarate hydratase aberration demonstrate morphological reproducibility across cases and S-(2-succino)-cysteine immuno-positivity. Although the features described are not specific for the germline fumarate hydratase mutation or the hereditary leiomyomatosis and renal cell carcinoma syndrome, their presence should suggest fumarate hydratase aberration. Identifying these cases is an important step in the diagnostic workup of patients with possible hereditary leiomyomatosis and renal cell carcinoma.

Components of cancer metabolism and therapeutic interventions

All forms of life share a common indispensible need of energy. The requirement of energy is necessary for an organism not only to survive but also to thrive. The metabolic activities in normal cells rely predominately on mitochondrial oxidative phophorylation for energy generation in the form of ATP. On the contrary, cancer cells predominately rely on glycolysis rather than oxidative phosphorylation. It is long believed that an impairment of mitochondrial oxidative phosphorylation is the cause of this glycolytic phenotype observed in cancers. However, studies in cancer metabolism have revealed that mitochondrial function in many cancers is intact. It has also been observed that cancers utilize various forms of metabolism. The various metabolic phenotypes that are employed by cancer cells have a common purpose, to balance macromolecular biosynthesis and sufficient ATP production in order to support the rapid proliferation rate characteristic of these aberrant cells. These metabolic pathways are attractive targets for possible therapeutic interventions and currently research is underway to meet this end. More importantly, normal cells have essentially the same metabolic requirements as cancer cells so finding an approach to target these metabolic pathways without incurring detrimental effects on normal tissues remains the challenge.

Morphologic and molecular characteristics of uterine leiomyomas in hereditary leiomyomatosis and renal cancer (HLRCC) syndrome

Hereditary leiomyomatosis and renal cell cancer (HLRCC) is a hereditary cancer syndrome in which affected individuals are predisposed to the development of multiple leiomyomas of the skin and uterus and aggressive forms of kidney cancer. Affected individuals harbor a germline heterozygous loss-of-function mutation of the fumarate hydratase (FH) gene. Uterine leiomyomas are present in up to 77% of women with this syndrome. Previous studies have shown that inactivation of the FH gene is unusual for nonsyndromic leiomyomas. Therefore, it might be possible to distinguish 2 genetic groups of smooth muscle tumors: the most common group of sporadic uterine leiomyomas without FH gene inactivation and the more unusual group of HLRCC leiomyomas in patients who harbor a germline mutation of FH, although the exact prevalence of hereditary HLRCC is unknown. We reviewed the clinical, morphologic, and genotypic features of uterine leiomyomas in 19 HLRCC patients with FH germline mutations. Patients with HLRCC syndrome were younger in age compared with those with regular leiomyomata. DNA was extracted by microdissection, and analysis of loss of heterozygosity (LOH) at 1q43 was performed. Uterine leiomyomas in HLRCC have young age of onset and are multiple, with size ranging from 1 to 8 cm. Histopathologically, HLRCC leiomyomas frequently had increased cellularity, multinucleated cells, and atypia. All cases showed tumor nuclei with large orangeophilic nucleoli surrounded by a perinucleolar halo similar to the changes found in HLRCC. Occasional mitoses were found in 3 cases; however, the tumors did not fulfill the criteria for malignancy. Our study also showed that LOH at 1q43 was frequent in HLRCC leiomyomas (8/10 cases), similarly to what has been previously found in renal cell carcinomas from HLRCC patients. LOH is considered to be the second hit that inactivates the FH gene. We conclude that uterine leiomyomas associated with HLRCC syndrome have characteristic morphologic features. Both, uterine leiomyomas and renal cell carcinoma share some morphologic nuclear changes and genotypic features in HLRCC patients. The specific morphologic features of the uterine leiomyomas that we describe may help in the identification of patients who may be part of the hereditary syndrome.

Genetic testing by cancer site: uterus

This review article discusses hereditary cancer predisposition syndromes with uterine manifestations. Lynch syndrome accounts for 2% to 3% of endometrial cancers. The identification of endometrial cancer patients at risk for Lynch syndrome is discussed, as are the characteristics of Lynch syndrome-associated endometrial cancer and the screening and prevention options for women at risk for Lynch syndrome-associated endometrial cancer. Endometrial cancer associated with PTEN hamartoma tumor syndrome (also known as Cowden syndrome) is also discussed. HLRCC (hereditary leiomyomatosis and renal cell carcinoma), which has an associated high risk of symptomatic uterine leiomyomas, is reviewed.

Involvement of proteasome β1i subunit, LMP2, on development of uterin leiomyosarcma

Background:

Although the majority of smooth muscle neoplasms found in the uterus are benign, uterine leiomyosarcoma is extremely malignant, with high rates of recurrence and metastasis. The development of gynecologic tumors is often correlated with secretion of female hormone; however, the development of human uterine leiomyosarcoma is not substantially correlated with hormonal conditions, and the risk factors are unclearly understood. Importantly, a diagnostic-biomarker, which distinguishes malignant human uterine leiomyosarcoma from benign tumor leiomyoma is yet to be established.

Aims:

It is necessary to analyze risk factors associated with human uterine leiomyosarcoma, in order to establish a diagnostic-biomarker and a clinical treatment method.

Patients and Methods:

Histology and Immunofluorescence Staining: Uteri obtained from LMP2^–/– mice or its parental mice (C57BL/6 mice) were fixed in 10% buffered formalin, incubated in 4% paraformaldehyde for 8 hours, and embedded in paraffin. Tissue sections (5 μm) were prepared and stained with H&E for routine histological examination or were processed further for immunofluorescence staining with appropriate antidodies. Furthermore, a total of 101 patients between 32 and 83 years of age and diagnosed as having smooth muscle tumors of the uterus were selected from pathological files. Immunohistochemistry staining for LMP2 was performed on serial human uterine leiomyosarcoma, leiomyoma and myometrium sections.

Results:

Homozygous deficient mice for a proteasome β1i subunit, LMP2 spontaneously develop uterine leiomyosarcoma, with a disease prevalence of ~40% by 14 months of age. Defective LMP2 expression in human uterine leiomyosarcoma was demonstrated, but present in human leiomyoma and myometrium.

Conclusions:

Loss in LMP2 expression may be one of the risk factors for human uterine leiomyosarcoma. LMP2 may be a potential diagnostic-biomarker and targeted-molecule for a new therapeutic approach.

Familial renal cancer as an indicator of hereditary leiomyomatosis and renal cell cancer syndrome

Hereditary Leiomyomatosis and Renal Cell Carcinoma (HLRCC) is a hereditary condition which typically presents with cutaneous and uterine leiomyomata. Papillary type II renal cell carcinoma and other less common histologic subtypes of renal cancer have been reported in HLRCC. We describe the case of a 31-year-old man in which the pathology review of his renal carcinoma and a positive family history of renal carcinoma allowed for the identification of a pathogenic mutation in the FH gene (c.698G>A;p.R233H) confirming the diagnosis of HLRCC. Recognition of this syndrome allowed for appropriate surveillance as well as identification of at-risk family members. Pathology review is essential for accurate diagnosis of a hereditary cancer syndrome in the setting of familial renal cancer.

Gastric leiomyoma and hyperplastic polyposis coli in a patient with multiple cutaneous and uterine leiomyomatosis

BACKGROUND

Cutaneous leiomyomatosis has been associated with multiple uterine myomas and, more recently, with germline heterozygous mutations of the FH gene and certain types of renal cancer. Despite the growing amount of knowledge concerning this genodermatosis, its clinical spectrum remains incompletely characterized.

OBJECTIVE

We report the observation of a patient with multiple cutaneous and uterine leiomyomatosis (MCUL) with unusual gastrointestinal manifestations.

METHODS AND RESULTS

A gastric leiomyoma was diagnosed on a 38-year-old female MCUL patient on endoscopy performed because of mild dyspepsia. Furthermore, routine colonoscopy disclosed hyperplastic polyposis. Genetic testing revealed a previously not reported mutation of the FH gene.

CONCLUSION

Gastrointestinal lesions such as the present ones are frequently asymptomatic and probably underdiagnosed. As the phenotypical spectrum associated with mutations of the FH gene keeps expanding, clinicians should keep in mind that, besides renal cancer, other unexpected tumors could also arise in this setting.

Potential role of LMP2 as an anti-oncogenic factor in human uterine leiomyosarcoma: morphological significance of calponin h1

Uterine leiomyosarcoma (LMS) is a highly metastatic smooth muscle neoplasm for which calponin h1 is suspected to have a biological role as a tumor-suppressor. We earlier reported that LMP2-null mice spontaneously develop uterine LMS through malignant transformation of the myometrium, thus implicating this protein as an anti-tumorigenic candidate as well. In the present study, we show that LMP2 may negatively regulate LMS independently of its role in the proteasome. Moreover, several lines of evidence indicate that although calponin h1 does not directly influence tumorigenesis, it clearly affects LMP2-induced cellular morphological changes. Modulation of LMP2 may lead to new therapeutic approaches in human uterine LMS.

Potential role of LMP2 as tumor-suppressor defines new targets for uterine leiomyosarcoma therapy

Although the majority of smooth muscle neoplasms found in the uterus are benign, uterine leiomyosarcoma (LMS) is extremely malignant, with high rates of recurrence and metastasis. We earlier reported that mice with a homozygous deficiency for LMP2, an interferon (IFN)-γ-inducible factor, spontaneously develop uterine LMS. The IFN-γ pathway is important for control of tumor growth and invasion and has been implicated in several cancers. In this study, experiments with human and mouse uterine tissues revealed a defective LMP2 expression in human uterine LMS that was traced to the IFN-γ pathway and the specific effect of JAK-1 somatic mutations on the LMP2 transcriptional activation. Furthermore, analysis of a human uterine LMS cell line clarified the biological significance of LMP2 in malignant myometrium transformation and cell cycle, thus implicating LMP2 as an anti-tumorigenic candidate. This role of LMP2 as a tumor suppressor may lead to new therapeutic targets in human uterine LMS.

Increased risk of secondary uterine leiomyosarcoma in hereditary retinoblastoma

OBJECTIVE

In the US, second non-ocular malignancies are the primary cause of death in retinoblastoma survivors with the germline RB1 mutation. Soft tissue sarcomas are one of the most likely malignancies to pose a risk to these patients, with leiomyosarcoma (LMS) being the most common subtype. As our cohort is followed for a longer period, we discover new second malignancy risks for these patients.

METHODS

We estimated the risk for uterine leiomyosarcoma (ULMS) in a cohort of 1854 patients with retinoblastoma who were diagnosed at two US institutions from 1914 through 1996. The standardized incidence ratio and excess absolute risk were calculated by comparison with population data from the Connecticut Tumor Registry or from National Cancer Institute Surveillance, Epidemiology, and End Results (SEER) database. The cumulative risk at 50 years of age was also calculated.

RESULTS

Seven of 525 female hereditary retinoblastoma patients developed ULMS. Five of these patients were used in the risk analysis, resulting in an excess risk of 3.87 per 10,000 women. Among hereditary patients who developed ULMS the excess risk increases dramatically with age: to 20/10,000 for female hereditary retinoblastoma patients aged between 30 and 39 years, and to 27/10,000 for patients aged 40+ years.

CONCLUSION

There is a substantial excess risk of ULMS in female hereditary retinoblastoma patients. As more patients survive into their thirties, this number is likely to increase. These findings raise the question of early childbearing, screening and prophylactic measures in hereditary retinoblastoma patients: all issues that would benefit from confirmation from other retinoblastoma cohorts, to allow for better guided counsel of these patients.

Hereditary leiomyomatosis and renal cell cancer in families referred for fumarate hydratase germline mutation analysis

Heterozygous fumarate hydratase (FH) germline mutations cause hereditary leiomyomatosis and renal cell cancer (HLRCC), an autosomal dominant syndrome characterized by multiple cutaneous piloleiomyomas, uterine leiomyomas and papillary type 2 renal cancer. The main objective of our study was to evaluate clinical and genetic data from families suspected of HLRCC on a nationwide level. All families referred for FH mutation analysis in the Netherlands were assessed. We performed FH sequence analysis and multiplex ligation-dependent probe amplification. Families with similar FH mutations were examined for haplotype sharing. In 14 out of 33 families, we identified 11 different pathogenic FH germline mutations, including 4 novel mutations and 1 whole-gene deletion. Clinical data were available for 35 FH mutation carriers. Cutaneous leiomyomas were present in all FH mutation carriers older than 40 years of age. Eleven out of 21 female FH mutation carriers underwent surgical treatment for symptomatic uterine leiomyomas at an average of 35 years. Two FH mutation carriers had papillary type 2 renal cancer and Wilms' tumour, respectively. We evaluated the relevance of our findings for clinical practice and have proposed clinical diagnostic criteria, indications for FH mutation analysis and recommendations for management.

Molecular Approach to Uterine Leiomyosarcoma: LMP2-Deficient Mice as an Animal Model of Spontaneous Uterine Leiomyosarcoma

Uterine leiomyosarcoma (LMS) develops more often in the muscle tissue layer of the uterine body than in the uterine cervix. The development of gynecologic tumors is often correlated with female hormone secretion; however, the development of uterine LMS is not substantially correlated with hormonal conditions, and the risk factors are not yet known. Importantly, a diagnostic-biomarker which distinguishes malignant LMS from benign tumor leiomyoma (LMA) is yet to be established. Accordingly, it is necessary to analyze risk factors associated with uterine LMS, in order to establish a treatment method. LMP2-deficient mice spontaneously develop uterine LMS, with a disease prevalence of ~40% by 14 months of age. We found LMP2 expression to be absent in human LMS, but present in human LMA. Therefore, defective LMP2 expression may be one of the risk factors for LMS. LMP2 is a potential diagnostic-biomarker for uterine LMS, and may be targeted-molecule for a new therapeutic approach.