Cryptic splice mutation in the fumarate hydratase gene in patients with clinical manifestations of Hereditary Leiomyomatosis and Renal Cell Cancer.

Hereditary leiomyomatosis and renal cell carcinoma (HLRCC) is an autosomal dominant condition characterized by the development of cutaneous and uterine leiomyomas and risk for development of an aggressive form of papillary renal cell cancer. HLRCC is caused by germline inactivating pathogenic variants in the fumarate hydratase (FH) gene, which encodes the enzyme that catalyzes the interconversion of fumarate and L-malate. We utilized enzyme and protein mobility assays to evaluate the FH enzyme in a cohort of patients who showed clinical manifestations of HLRCC but were negative for known pathogenic FH gene variants. FH enzyme activity and protein levels were decreased by 50% or greater in three family members, despite normal FH mRNA expression levels as measured by quantitative PCR. Direct Nanopore RNA sequencing demonstrated 57 base pairs of retained intron sequence between exons 9 and 10 of polyadenylated FH mRNA in these patients, resulting in a truncated FH protein. Genomic sequencing revealed a heterozygous intronic alteration of the FH gene (chr1: 241498239 T/C) resulting in formation of a splice acceptor site near a polypyrimidine tract, and a uterine fibroid obtained from a patient showed loss of heterozygosity at this site. The same intronic FH variant was identified in an unrelated patient who also showed a clinical phenotype of HLRCC. These data demonstrate that careful clinical assessment as well as biochemical characterization of FH enzyme activity, protein expression, direct RNA sequencing, and genomic DNA sequencing of patient-derived cells can identify pathogenic variants outside of the protein coding regions of the FH gene.

Segregation, immunohistochemical, molecular and functional analyses classify a novel missense variant in fumarate hydratase (FH) as pathogenic.

Hereditary leiomyomatosis and renal cell cancer (HLRCC) is an autosomal dominant cancer predisposition syndrome characterized by cutaneous leiomyomas, uterine leiomyomas, and aggressive renal cancer. Germline variants in the fumarate hydratase (FH) gene predispose to HLRCC. Identifying germline pathogenic FH variants enables lifetime renal cancer screening and genetic testing for family members. In this report, we present a FH missense variant (c.1039T>C (p.S347P)), initially classified as a variant of uncertain significance. Clinical assessment, histopathological findings, molecular genetic studies, and enzymatic activity studies support the re-classification of the FH c.1039T>C variant to "pathogenic" based on ACMG/AMP criteria. Further insights into pathological recognition of FH-deficient renal cancer are discussed and should be recognized. This study has shown how (a) detailed multi-disciplinary analyses of a single variant can reclassify rare missense variants in FH and (b) careful pathological review of renal cancers is obligatory when HLRCC is suspected.

Safety and efficacy of sirolimus in recurrent intravenous leiomyomatosis, pulmonary benign metastatic leiomyomatosis, and leiomyomatosis peritonealis disseminata: a pilot study.

BACKGROUND: Intravenous leiomyomatosis (IVL), pulmonary benign metastatic leiomyomatosis (PBML), and leiomyomatosis peritonealis disseminata (LPD) are leiomyomas with special growth patterns and high postoperative recurrence rates. We report the safety and efficacy of a pilot study of sirolimus in the treatment of recurrent IVL, PBML, and recurrent LPD. METHODS: This was a pilot study to evaluate the safety and efficacy of sirolimus in the treatment of leiomyomatosis (ClinicalTrials.gov identifier NCT03500367) conducted in China. Patients received oral sirolimus 2 mg once a day for a maximum of 60 months or until disease progression, intolerable toxicity, withdrawal of consent, or investigator decision to stop. The primary end point of this study was the objective response rate. Secondary end points included safety and tolerability, disease control rate, and progression-free survival. RESULTS: A total of 15 patients with leiomyomatosis were included in the study, including five with recurrent IVL, eight with PBML and two with recurrent LPD. The median follow-up time was 15 months (range 6-54 months), nine patients (60%) had treatment-related adverse events (including all levels), and two patients had treatment-related grade 3 or 4 adverse events. The objective response rate was 20.0% (95% CI, 7.1-45.2%), and the disease control rate was 86.7% (95% CI, 62.1-96.3%). Partial response was achieved in three patients. The median response time in the three partial response patients was 33 months (range 29-36 months), and the sustained remission time of these three patients reached 0, 18, and 25 months, respectively. CONCLUSIONS: Sirolimus was safe and effective in the treatment of recurrent IVL, PBML, and recurrent LPD. TRIAL REGISTRATION: ClinicalTrials.gov identifier NCT03500367. Registered on 18 April 2018.

Malignant glomus tumor arising in association with a fumarate hydratase-deficient leiomyoma: An unusual collision tumor.

Collision tumors, defined as "two independent neoplasms that occur in close proximity to one another but maintain distinct boundaries," are quite rare. We report an exceptional collision tumor composed of a genetically confirmed malignant glomus tumor and a fumarate hydratase (FH)-deficient leiomyoma, presenting as a subcutaneous thigh mass in a 38-year-old male who was known to have hereditary leiomyomatosis and renal cell carcinoma syndrome. Microscopic examination identified a biphasic subcutaneous mass comprising sheets and nodules of glomus cells, with nuclear atypia and mitotic activity, and fascicles of mitotically inactive smooth muscle with variably pleomorphic nuclei and intracytoplasmic eosinophilic inclusions, features of FH-deficient leiomyoma. Immunohistochemistry demonstrated loss of FH and robust 2-succinocysteine expression in the smooth muscle, with a normal (FH-retained) expression pattern in the glomus tumor. Next-generation sequencing, performed on the glomus tumor component, identified CARMN::NOTCH2 fusion, characteristic of malignant glomus tumors. Awareness of the distinctive morphologic, immunohistochemical, and molecular genetic features of glomus tumors and FH-deficient leiomyomas is important for correct clinical management of patients with exceptional collision tumors of this type.

Analysis of risk factors for post-operative recurrence or progression of intravenous leiomyomatosis.

OBJECTIVE: To analyse the risk factors for post-operative recurrence or progression of intravenous leiomyomatosis and explore the impact of different treatment strategies on patient prognosis. METHODS: Patients with intravenous leiomyomatosis who underwent surgery from January 2011 to December 2020 and who were followed for ≥3 months were included. The primary endpoint was recurrence (for patients with complete resection) or progression (for patients with incomplete resection). Kaplan-Meier survival analysis was used to analyse the factors affecting recurrence. RESULTS: A total of 114 patients were included. The median age was 45 years old (range 24-58). The tumors were confined to the uterus and para-uterine vessels in 48 cases (42.1%), while in 66 cases (57.9%) it involved large vessels (iliac vein or genital vein and/or proximal large veins). The median follow-up time was 24 months (range 3-132). Twenty-nine patients (25.4%) had recurrence or progression. The median recurrence or progression time was 16 months (range 3-60). Incomplete tumor resection (p=0.019), involvement of the iliac vein or genital vein (p=0.042), involvement of the inferior vena cava (p=0.025), and size of the pelvic tumor ≥15 cm (p=0.034) were risk factors for recurrence and progression. For intravenous leiomyomatosis confined to the uterus or para-uterine vessels, no post-operative recurrence after hysterectomy and bilateral oophorectomy occurred in this cohort. Compared with hysterectomy and bilateral oophorectomy, the risk of recurrence after tumorectomy (with the uterus and ovaries retained) was significantly greater (p=0.009), while the risk of recurrence after hysterectomy was not significantly increased (p=0.058). For intravenous leiomyomatosis involving the iliac vein/genital vein and the proximal veins, post-operative aromatase inhibitor treatment (p=0.89) and two-stage surgery (p=0.86) were not related to recurrence in patients with complete tumor resection. CONCLUSION: Incomplete tumor resection, extent of tumor lesions and size of the pelvic tumor were risk factors for post-operative recurrence and progression of intravenous leiomyomatosis.

Clinical phenotype and genetic function analysis of a rare family with hereditary leiomyomatosis and renal cell carcinoma complicated with Birt-Hogg-Dubé syndrome.

To date, over 200 families with hereditary leiomyomatosis and renal cell carcinoma (HLRCC) and over 600 families with Birt-Hogg-Dubé (BHD) syndrome have been reported, with low incidence. Here, we describe a patient with suspected rare HLRCC complicated by BHD syndrome. The proband (II1) had characteristic cutaneous leiomyoma-like protrusions on the neck and back, a left renal mass and multiple right renal, liver and bilateral lung cysts. Three family members (I1, II2, II3) had a history of renal cancer and several of the aforementioned clinical features. Two family members (II1, II3) diagnosed with fumarate hydratase (FH)-deficient papillary RCC via pathological biopsy carried two heterozygous variants: FH (NM_000143.3) missense mutation c.1189G>A (p.Gly397Arg) and FLCN (NM_144997.5) frameshift mutation c.1579_1580insA (p.Arg527Glnfs*75). No family member carrying a single variant had renal tumours. In HEK293T cells transfected with mutant vectors, mRNA and protein expression after FLCN p.Arg527Glnfs*75 and FH p.Gly397Arg mutations were significantly lower than those in wild-type (WT) cells. Cell immunofluorescence showed altered protein localisation and reduced protein expression after FLCN p.Arg527Glnfs*75 mutation. The FH WT was uniformly distributed in the cytoplasm, whereas FH protein expression was reduced after the p.Gly397Arg mutation and scattered sporadically with altered cell localisation. Patients with two variants may have a significantly increased penetrance of RCC.

Cost-effectiveness model of renal cell carcinoma (RCC) surveillance in hereditary leiomyomatosis and renal cell carcinoma (HLRCC).

PURPOSE: To determine the cost-effectiveness of annual renal imaging surveillance (RIS) in hereditary leiomyomatosis and renal cell cancer (HLRCC). HLRCC is associated with a 21% risk to age 70 years of RCC. Presentations with advanced renal cell cancer (RCC) are associated with poor outcomes whereas RIS detects early-stage RCC; however, evidence for the cost-effectiveness of RIS is lacking. METHODS: We developed a decision-analytic model to compare, at different age starting points (11 years, 18 years, 40 years, 60 years), the costs and benefits of lifetime contrast-enhanced renal MRI surveillance (CERMRIS) vs no surveillance in HLRCC. Benefits were measured in life-years gained (LYG), quality-adjusted life years (QALYs) and costs in British Pounds Sterling (GBP). Net monetary benefit (NMB) was calculated using a cost-effectiveness threshold of £20 000/QALY. One-way sensitivity and probabilistic analyses were also performed. RESULTS: In the base-case 11-year age cohort, surveillance was cost-effective (Incremental_NMB=£3522 (95% CI -£2747 to £7652); Incremental_LYG=1.25 (95% CI 0.30 to 1.86); Incremental_QALYs=0.29 (95% CI 0.07 to 0.43)] at an additional mean discounted cost of £2185/patient (95% CI £430 to £4144). Surveillance was also cost-effective in other age cohorts and dominated a no surveillance strategy in the 40 year cohort [Incremental_NMB=£12 655 (95% CIs -£709 to £21 134); Incremental_LYG=1.52 (95% CI 0.30 to 2.26); Incremental_QALYs=0.58 (95% CI 0.12 to 0.87) with a cost saving of £965/patient (95% CI -£4202 to £2652). CONCLUSION: Annual CERMRI in HLRCC is cost-effective across age groups modelled.

Diffuse uterine leiomyomatosis: a rare discovery.

PURPOSE: This case report aims to present a rare and challenging clinical scenario involving diffuse uterine leiomyomatosis (DUL), an infrequently encountered benign uterine pathology. The primary objective is to describe this unique case's clinical presentation, diagnostic challenges, and subsequent management. METHODS: A detailed analysis of the patient's medical history, diagnostic evaluations, and treatment approach was conducted. A relevant literature review on DUL was also performed. This case report includes high-resolution images and figures, showcasing MRI scans, surgical procedures, and histopathology slides related to the case. RESULTS: The case report outlines the clinical journey of a patient with DUL, an exceptionally rare uterine condition characterized by the uncontrolled proliferation of smooth muscle cells forming nodules and fascicles. This case illustrates the diagnostic complexities associated with DUL, as it mimics other uterine pathologies such as leiomyomas or adenomyosis. The patient's clinical presentation included abnormal uterine bleeding, heavy menstrual bleeding, fertility issues, and dysmenorrhea, leading to initial misdiagnoses. Surgical intervention eventually addressed the condition with corresponding images illustrating the procedures. CONCLUSION: This case report highlights DUL's rarity and diagnostic challenges. Clinicians must be vigilant when encountering similar clinical presentations, ensuring a comprehensive diagnostic workup to differentiate DUL from other uterine pathologies. Enhanced awareness among healthcare providers and further research into DUL's pathophysiology is essential for accurate diagnosis and timely management. The presented case underscores the need for tailored approaches to managing DUL and expanding the knowledge base surrounding this puzzling uterine disorder.

Unraveling the challenges of intravenous leiomyomatosis: a retrospective analysis of 11 cases.

OBJECTIVE: This study provides a concise overview of diagnostic and treatment strategies for intravenous leiomyomatosis (IVL), a rare disease with nonspecific clinical manifestations, based on cases from a tertiary referral hospital in China. METHODS: We retrospectively analyzed 11 premenopausal patients with confirmed IVL between 2018 and 2022. Clinical data from Ultrasound, Enhanced CT, and MRI were studied, along with surgical details, postoperative pathology, and follow-up information. RESULTS: Premenopausal patients showed no disease-specific symptoms, with 90.9% having a history of gynecological or obstetric surgery, and 72.7% having prior uterine fibroids. Cardiac involvement was evident in two cases, with echocardiography detecting abnormal floating masses from the inferior vena cava. Pelvic ultrasound indicated leiomyoma in 90.9% of cases, with ≥ 50 mm size. Surgery was the primary treatment, and lesions above the internal iliac vein resulted in significantly higher intraoperative blood loss (median 1300 ml vs. 50 ml, p = 0.005) and longer hospital stays (median 10 days vs. 4 days, p = 0.026). Three patients with lesions above the inferior vena cava required combined surgery with cardiac specialists. Recurrence occurred in 2 out of 11 patients with incomplete lesion resection. CONCLUSIONS: IVL mainly affects premenopausal women with uterine masses, primarily in the pelvic cavity (Stage I). Pelvic ultrasound aids early screening, while Enhanced CT or MR assists in diagnosing and assessing venous lesions. Complete resection is crucial to prevent recurrence. Lesions invading the internal iliac vein and above pose higher risks during surgery. A multidisciplinary team approach is essential for patients with lesions above the inferior vena cava, with simultaneous surgery as a potential treatment option.

Arteriovenous Malformation Associated with Intravenous Leiomyomatosis of the Uterus: Characteristic CT Findings and Treatment by Embolization and Surgery.

Seven consecutive female patients with pathologically confirmed arteriovenous malformation (AVM) with intravenous leiomyomatosis (IVL) of the uterus (age range, 32-61 years; mean age, 43 years) treated between 2005 and 2021 from a single institution were reviewed. Computed tomography (CT) findings of congenital pelvic AVM of 10 female patients were compared with those of AVM with IVL. Characteristic CT findings of AVM with IVL revealed a focal soft tissue mass inside a dilated venous structure of the AVM. Multiple sessions of transvenous coil embolization of the AVM with or without the injection of ethanol were performed. After complete (6/7, 86%) or partial (1/7, 14%) embolization of the AVM, complete surgical resection of the IVL and embolized AVM mass was performed in 4 patients. Patients with lung metastasis or residual embolized AVM masses are under follow-up with antiestrogen hormonal therapy.

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.

Successful pregnancies in women with diffuse uterine leiomyomatosis after high-intensity focused ultrasound ablation: report of three cases.

OBJECTIVE: To describe the reproductive outcomes of patients with diffuse uterine leiomyomatosis (DUL) treated with high-intensity focused ultrasound (HIFU) ablation. MATERIALS AND METHODS: Three patients of reproductive age with DUL who underwent HIFU treatment were enrolled, all of whom had a strong desire to become pregnant. All patients underwent routine laboratory tests, electrocardiography (ECG), chest X-ray radiography, ultrasound, and magnetic resonance imaging (MRI) examinations after routine medical history collection and physical examination. The treatment time, treatment power, sonication time, and adverse events were recorded. One day after HIFU, MRI was performed to evaluate treatment efficacy. The patients were scheduled for follow-up at 3-, 6-, 12-, and 24-month after HIFU treatment. RESULTS: All the three patients completed HIFU treatment successfully without any major complication. Uterine size and menstrual volume significantly decreased with the combination of medical and HIFU treatments. The shrinkage rate of uterine volume was 31-44% and the menstrual volume reduced by 1/2 or returned to normal at 3 months post-HIFU. Three patients had successful conceptions between 3 and 11 months after HIFU with healthy deliveries. No uterine rupture occurred during pregnancy and delivery. CONCLUSION: HIFU ablation may help achieve a successful pregnancy in patients with DUL.

Imaging diagnosis of intravenous leiomyomatosis: an institutional experience.

AIM: To review and summarise the clinical and imaging characteristics of intravenous leiomyomatosis (IVL), a rare smooth muscle tumour originating from the uterus. MATERIALS AND METHODS: Twenty-seven patients with a histopathological diagnosis of IVL who underwent surgery were reviewed retrospectively. All patients underwent pelvic ultrasonography, inferior vena cava (IVC) ultrasonography, and echocardiography before surgery. Computed tomography (CT) with contrast enhancement was performed in patients with extrapelvic IVL. Some patients underwent pelvic magnetic resonance imaging (MRI). RESULTS: Mean age was 44.81 years. Clinical symptoms were non-specific. IVL was intrapelvic in seven patients and extrapelvic in 20. Preoperative pelvic ultrasonography missed the diagnosis in 85.7% of patients with intrapelvic IVL. Pelvic MRI was useful to evaluate the parauterine vessels. Incidence of cardiac involvement was 59.26%. Echocardiography showed a highly mobile sessile mass in the right atrium with moderate-to-low echogenicity that originates from the IVC. Ninety per cent of extrapelvic lesions showed unilateral growth. The most common growth pattern was via the right uterine vein-internal iliac vein-IVC pathway. CONCLUSION: The clinical symptoms of IVL are non-specific. For patients with intrapelvic IVL, early diagnosis is difficult. Pelvic ultrasound should focus on the parauterine vessels, the iliac and ovarian veins should be explored carefully. MRI has obvious advantages in evaluating parauterine vessel involvement, which is helpful for early diagnosis. For patients with extrapelvic IVL, CT should be performed before surgery as part of a comprehensive evaluation. IVC ultrasonography and echocardiography are recommended when IVL is highly suspected.

"Evolution" of intravascular leiomyomatosis.

BACKGROUND: Intravenous leiomyomatosis (IVL) is a rare and specific type of smooth muscle tumor that is histologically benign but has a malignant biological behavior. It is commonly associated with a history of uterine leiomyomas. CASE PRESENTATION: A 36-year-old woman, G1P1, presented to the hospital with left lower abdominal pain for 2 months and she has accepted hysteroscopic myomectomy about 1 year ago. Ultrasound venography, echocardiography and computed tomography venography (CTV) of inferior vena cava were performed, which revealed IVL located in left intramural myometrium walls growing along the left ovarian vein reaching the level of the lumbar 5-sacral 1 disc. Laparoscopic bilateral salpingo-oophorectomy and hysterectomyis were scheduled. The IVL in the left ovarian vein and parauterine venous plexus were detected and excised completely during surgery. IVL was diagnosed by postoperative pathology and immunohistochemistry. The patient recovered well after surgery. No surgical-related or anesthesia-related complications occurred.The 3-month follow-up CTV of inferior vena cava and echocardiography examination revealed normal. CONCLUSIONS: The cause of IVL is unknown, this observation demonstrates that hysteroscopic myomectomy might lead to the occurrence of IVL.

Laparoscopic Management of Disseminated Peritoneal Leiomyomatosis.

STUDY OBJECTIVE: To show laparoscopic management of disseminated peritoneal leiomyomatosis (DPL). DESIGN: Stepwise demonstration of the technique with narrated video footage. SETTING: DPL is characterized by dissemination and proliferation of peritoneal and subperitoneal lesions primarily originating from smooth muscle cells [1]. Generally considered benign, cases of malignant transformation to leiomyosarcoma have been reported [2,3]. Iatrogenic DPL occurs because of unconfined morcellation resulting in small fragments of myoma that may implant on any organ and start deriving blood supply from it or may be pulled into port site while withdrawing laparoscopic cannulas [4]. It is estimated that the overall incidence of DPL after laparoscopic uncontained morcellation was 0.12% to 0.95% [5]. Mainstay of treatment is surgical resection of myomas and regular follow-up with imaging. A 28-year-old unmarried girl presented with complain of lump abdomen increasing in size for 1 year. She also complained of a 15 kg weight loss in the last 1 year; 4 years ago, patient had undergone laparoscopic myomectomy with unconfined morcellation for a 10 × 8 cm cervical myoma. Presently her menses were regular with a 28-day cycle and 3 to 4 days' average flow. Magnetic resonance imaging showed multiple nodular lesions of varying sizes in relation to small bowel, colon, uterus, and anterior abdominal wall  suggestive of DPL. Bilateral ovaries were normal. Tumor markers were as follows: CA 125 23.2 (<35) U/mL Carcinoembryonic antigen 1.67 (<8) ng/mL CA 19-9 47 (<37) U/mL Lactate dehydrogenase 809 (180-360) IU/L Alpha-fetoprotein 2.03 (<10) ng/mL Beta human chorionic gonadotropin 1.2(<2) mIU/mL Tru-cut biopsy was done elsewhere to rule out peritoneal carcinomatosis in view of raised CA 19-9 and lactate dehydrogenase, history of weight loss, and imaging showing multiple abdominal masses. Histopathological examination showed leiomyomatosis and immunohistochemistry for smooth muscle actin, desmin, and vimentin were positive. INTERVENTIONS: On laparoscopy the abdominal cavity was found studded with multiple leiomyomas of varying sizes deriving blood supply from ilium, transverse, descending and sigmoid colon, rectum, left tube, left ovary, pouch of Douglas, bilateral uterosacrals, uterovesical fold, and anterior abdominal wall. Large blood vessels were seen traversing between the descending and sigmoid colon and the myomas. Principles of surgery were as follows: 1. Complete removal of myomas 2. Cauterization of blood vessels feeding the parasitic myomas to minimize blood loss 3. Disscetion abutting the myoma to prevent injury to adjacent viscera. A total of 26 myomas were removed. All the myomas were retrieved by morcellation in a bag. Histopathology confirmed the diagnosis of diffuse peritoneal leiomyomatosis. Follow-up ultrasound at 6 months showed no recurrence of leiomyomatosis. CONCLUSION: Proper mapping of lesions and surgery for complete removal of all masses is the mainstay of treatment. Contained morcellation in bag should be the norm to prevent iatrogenic DPL. Regular follow-up with imaging is required to rule out recurrence.

Intravenous leiomyomatosis involving the right heart: Comprehensive evaluation using echocardiography combined with abdominal ultrasonography.

Intravenous leiomyomatosis (IVL) is a rare condition characterized by a tumor that originates within a pelvic vein wall or the uterine smooth muscle, with extension into the right heart (referred to as intracardiac leiomyomatosis) in approximately 10% of all IVL cases. Usually, computed tomography (CT) or magnetic resonance imaging (MRI) is performed for diagnostic imaging of IVL. Notably, this neoplasm presents with characteristic ultrasonographic findings. In this report, we present the case of a 49-year-old woman with IVL, which extended into the right heart. Echocardiography combined with abdominal ultrasonography was useful to outline the course of the tumor from the right heart to the uterus. Our findings suggest that in addition to CT or MRI, ultrasonography shows high diagnostic value in cases of IVL, and ultrasonography combined with CT or MRI can further improve the preoperative diagnosis rate of IVL.

[FH (Fumarate Hydratase)-deficient renal cell carcinoma: A case report]. / Carcinome à cellules rénales FH (fumarate hydratase)-déficient : à propos d'un cas.

Fumarate hydratase deficient renal cell carcinoma (FH-RCC) is a rare malignant neoplasia caused by constitutive or somatic mutations in the FH gene whose diagnosis is primordial, requiring genetic counselling. Because of histological heterogeneity, such tumors have been in the past misclassified as "type 2 papillary carcinoma", "tubulo-cystic renal cell carcinoma" or "high grade papillary carcinoma". We report here a case of FH deficient renal cell carcinoma (FH-RCC) in a 69years old patient. Through this observation, we precise the epidemiological and histological aspects and diagnosis criteria of this rare tumor.

[Fumarate hydratase deficient uterine leiomyoma: a clinicopathological and molecular analysis of 80 cases].

Objective: To investigate the clinicopathologic and molecular characteristics of fumarate hydratase (FH) deficient uterine leiomyoma. Methods: Eighty cases of FH deficient uterine leiomyoma were diagnosed from April 2018 to September 2022 in Department of Pathology, Peking University Third Hospital. Sanger sequencing of FH gene exons (exon 1-10) were performed on tumor tissues and matched non-tumor tissues/peripheral blood for all cases. FH immunohistochemistry were performed in 74 cases; S-(2-succino)-cysteine (2SC) were also detected by immunohistochemistry in five cases. Results: Patients' age ranged from 18 to 54 (36.0±7.5) years, with more than 60% exhibiting clinical symptoms of multiple and large leiomyomas (the median diameter was 70 mm). More than four histologic features, including staghorn vasculature, alveolar-pattern edema, bizarre nuclei, oval nuclei arranged in chains, prominent eosinophilic nucleoli with perinucleolar haloes and eosinophilic intracytoplasmic globules were observed in 98.5% (67/68) patients. The immunohistochemical sensitivity of FH and 2SC were 97.3% and 100%, respectively. Based on the Sanger sequencing results, the cases were divided into germline variant group (31 cases), somatic variant group (29 cases) and no variant group (20 cases). Sixty-nine percent (20/29) of the patients with FH germline variation had clear family history. Conclusions: Clinical features, histological morphology, FH and 2SC immunohistochemistry and Sanger sequencing have their own significance and limitations in differential diagnosis of FH deficient uterine leiomyoma. In clinical practice, the above information should be fully integrated and studied for accurate pathologic diagnosis and selection of patients with FH germline variation.

[Diagnosis and treatment of intravenous leiomyomatosis].

Intravenous leiomyomatosis is a rare type of tumor that is histologically benign but biologically invasive. It originates from the smooth muscle of the uterine or the uterine vein. It can grow through the uterus and extend into the pelvic cavity, or grow along the veins without invading the wall of the venous vessel itself. The tumors are estrogen-dependent and can metastasize through the bloodstream. Thus, in addition to continuous growth, some tumors exhibit isolated growths in the venous system and heart chambers or show disseminated growth in the lungs, although distant metastasis to other regions usually do not occur. Currently, there is limited research on this disease, the majority of which are case reports, surgical experience summaries, and differentiation from ordinary gynecological myomas in terms of pathogenesis and radiological diagnostic experience. There are two main theories on the origin of the disease: uterine smooth muscle and smooth muscle of the uterine veins. Some studies have verified the role of estrogen, progesterone receptor-related pathways, and angiogenesis in the development of the disease. The clinical symptoms of this disease are varied, depending on the affected area. In the early stages, when the tumor only affects the pelvic cavity, patients show mild symptoms resulting from pelvic organ compression. When it progresses to the inferior vena cava and heart, patients show more complex symptoms resulting from venous return obstruction, cardiac obstruction, and hemodynamics appearing. Different institutions have proposed different disease staging and classification strategies for different clinical purposes. Some are based on the affected area of the lesion; others are based on the size of the tumor. Although surgery remains the main treatment for this disease, the specific surgical approach, adjuvant drug therapy, and prognosis still need further exploration.

Fumarate hydratase variant prevalence and manifestations among individuals receiving germline testing.

BACKGROUND: Germline variants in fumarate hydratase (FH) are associated with autosomal dominant (AD) hereditary leiomyomatosis and renal cell cancer (HLRCC) and autosomal recessive (AR) fumarase deficiency (FMRD). The prevalence and cancer penetrance across different FH variants remain unclear. METHODS: A database containing 120,061 records from individuals undergoing cancer germline testing was obtained. FH variants were classified into 3 categories: AD HLRCC variants, AR FMRD variants, and variants of unknown significance (VUSs). Individuals with variants from these categories were compared with those with negative genetic testing. RESULTS: FH variants were detected in 1.3% of individuals (AD HLRCC, 0.3%; AR FMRD, 0.4%; VUS, 0.6%). The rate of AD HLRCC variants discovered among reportedly asymptomatic individuals without a clear indication for HLRCC testing was 1 in 2668 (0.04%). In comparison with those with negative genetic testing, the renal cell carcinoma (RCC) prevalence was elevated with AD HLRCC variants (17.0% vs 4.5%; P < .01) and VUSs (6.4% vs 4.5%; P = .02) but not with AR FMRD variants. CONCLUSIONS: The prevalence of HLRCC discovered incidentally on germline testing is similar to recent population carrier estimates, and this suggests that this is a relatively common cancer syndrome. Compared with those with negative genetic testing, those with VUSs had an elevated risk of RCC, whereas those with AR FMRD variants did not.