Dysregulation of ribosome-associated quality control elicits cognitive disorders via overaccumulation of TTC3.

Ribosome-associated quality control (RQC) pathway is responsible for degradation of nascent polypeptides in aberrantly stalled ribosomes, and its defects may lead to neurological diseases. However, the underlying molecular mechanism of how RQC dysfunction elicits neurological disorders remains poorly understood. Here we revealed that neurons with knockout (KO) of ubiquitin ligase LTN1, a key gene in the RQC pathway, show developmental defects in neurons via upregulation of TTC3 and UFMylation signaling proteins. The abnormally enhanced TTC3 protein in Ltn1 KO neurons reduced further accumulation of translationally arrested products by preventing translation initiation of selective genes. However, the overaccumulated TTC3 protein in turn caused dendritic abnormalities and reduced surface-localized GABAA receptors during neuronal development. Ltn1 KO mice showed behavioral deficits associated with cognitive disorders, a subset of which were restored by TTC3 knockdown in medial prefrontal cortex. Together, the overactivated cellular compensatory mechanism against defective RQC through TTC3 overaccumulation induced synaptic and cognitive deficits. More broadly, these findings represent a novel cellular mechanism underlying neuronal dysfunctions triggered by exaggerated cellular stress response to accumulated abnormal translation products in neurons.

A case of A20 haploinsufficiency complicated by autoimmune hepatitis.

AIM: A20 haploinsufficiency (HA20) is a recently described autoinflammatory disease that manifests symptoms similar to those of Behçet's disease. However, little is known about the involvement of the liver in HA20. Here, we report a case of HA20 complicated by autoimmune hepatitis (AIH). CASE PRESENTATION: A 33-year-old woman was previously diagnosed with HA20 and chronic thyroiditis, and was treated with prednisolone (PSL; 7.5 mg/day) and levothyroxine sodium hydrate (125 µg/day). She experienced general malaise and jaundice, and biochemical evaluation revealed elevated liver function with an aspartate aminotransferase level of 817 U/L, an alanine aminotransferase level of 833 U/L, and a total bilirubin of 8.3 mg/dL. Pathological evaluation of the liver biopsy revealed interface hepatitis and the patient was diagnosed with acute exacerbation of AIH. Upon increasing the PSL dose to 60 mg/day, the liver enzyme levels rapidly decreased. During tapering of PSL, azathioprine 50 mg/day was added, and there was no relapse of AIH with combination therapy of PSL 7 mg/day and azathioprine 50 mg/day. CONCLUSION: This is the first report of biopsy-proven AIH in an Asian patient with HA20. This case has significant implications for the pathogenesis and treatment of AIH in patients with HA20.

Novel insights into presenilin 1 mutation associated with a distinctive dementia phenotype and cotton wool plaques.

BACKGROUND: The mutations in the presenilin 1 gene (PSEN1) are the main cause of familial Alzheimer's disease. PSEN1 mutations affect amyloid-beta peptide production, which accumulates in the brain as senile plaque and cotton wool plaques (CWPs) and relates to other neurodegenerative disorders. Here we report the second case of the PSEN1 G266S mutation, which showed distinctive neuropathological features, including abundant CWPs. Lewy body pathology, and altered amyloid-beta production. METHOD: Using the proband's samples, we performed genetic analysis of the PSEN1, APP, MAPT, and APOE genes, histopathological and immunohistochemical analysis of the brain tissue, and biochemical analysis of Aß production in COS cells transfected with wild-type or mutant PSEN1. RESULTS: The patient presented with memory loss, abnormal behavior, and visual hallucinations. Brain scans showed reduced blood flow, mild atrophy, and white matter lesions. Genetic analysis revealed a heterozygous mutation at codon 266 (G266S) of PSEN1 and polymorphism of MAPT (Q230R). The brain had many CWPs, severe cerebral amyloid angiopathy (CAA), senile plaque, Lewy bodies, and neurites. Electron microscopy displayed myelinated fiber degeneration, mitochondrial damage, and amyloid fibrils in the white matter. The production level of Aß42 in PSEN1 G266S-transfected cells significantly increased. CONCLUSION: Our findings suggest that the PSEN1 G266S mutation may cause a heterogeneous clinical and pathological phenotype, influenced by other genetic or environmental factors.

Magnetic Resonance Imaging Features for Differentiating Low-Grade and High-Grade Malignant Peripheral Nerve Sheath Tumors.

OBJECTIVE: This study aimed to assess the usefulness of magnetic resonance imaging (MRI) findings for differentiating low-grade and high-grade malignant peripheral nerve sheath tumors (MPNSTs). METHODS: This study included 31 patients (onset age range, 19-83 years; mean onset age, 57 years; 9 men and 22 women) with 36 histopathologically proven MPNSTs (7 low-grade MPNSTs and 29 high-grade MPNSTs) who underwent preoperative MRI between December 2007 and October 2022. Quantitative and qualitative MRI findings were retrospectively evaluated and compared between the 2 subtypes. RESULTS: The maximum tumor diameter (106.1 ± 64.0 vs 54.9 ± 19.8 mm, P = 0.032) and tumor-to-muscle signal intensity ratio (SIR) of fat-suppressed gadolinium-enhanced T1-weighted images (2.69 ± 1.40 vs 1.62 ± 0.40, P = 0.005) were significantly higher in high-grade MPNSTs than in low-grade MPNSTs. The receiver operating characteristic analysis revealed that the tumor-to-muscle SIR of fat-suppressed gadolinium-enhanced T1-weighted images exhibited the highest area under the curve value (0.88), followed by the maximum tumor diameter (0.76). The sensitivity and specificity of the tumor-to-muscle SIR of fat-suppressed gadolinium-enhanced T1-weighted images for diagnosing high-grade MPNST at an optimal SIR threshold of greater than 1.73 were 90% and 83%, respectively. However, other MRI findings showed no significant differences between the 2 subtypes (P = 0.16-1.00). CONCLUSIONS: Although the MRI findings of low-grade and high-grade MPNST overlapped considerably, the maximum tumor diameter and degree of contrast enhancement can be used to differentiate low-grade MPNST from high-grade MPNST.

MRI features of subcutaneous anterior knee mass associated with a focal defect of the patellar retinaculum.

OBJECTIVE: The purpose of this study was to assess the frequency and MRI features of a subcutaneous anterior knee mass herniated from the infrapatellar fat pad (IPFP) through a focal defect of the patellar retinaculum (PR). MATERIALS AND METHODS: This study included 94 patients (44 men; age range, 1-80 years; mean age, 52 years) with clinically palpable subcutaneous anterior knee masses who underwent MRI between January 2007 and July 2022. Two radiologists retrospectively reviewed MRI findings of subcutaneous masses associated with a focal PR defect (location and size of the defect and characteristics of the mass). RESULTS: Among 94 patients, 15 (16%; 5 men; age range, 49-80 years; mean age, 67 years) had subcutaneous masses herniated from the IPFP through a focal PR defect. The defect was single (13/15, 87%) and more frequently observed in the lateral than in the medial (11/15, 73% vs. 4/15, 27%) PR. The defect occurred in the anterior segment (15/15, 100%) and was more frequently observed in the lower (10/15, 67%) than in the middle (5/15, 33%) and upper portions (0/15, 0%). The mean maximum length of the defect in axial and oblique planes was 14 mm and 25 mm, respectively. The defect-associated subcutaneous masses included lipomatous lesion (6/15, 40%), osteochondromatous lesion (5/16, 33%), and synovial fluid or ganglion cyst (4/15, 27%). CONCLUSION: Subcutaneous anterior knee masses were associated with a focal PR defect in 16% cases. The location of a focal PR defect was characterized by the lateral, anterior, and lower segments.

Expert perspectives on pathological findings in vasculitis.

Pathological findings are important in the diagnosis of vasculitis. However, due to the rarity of the disease, standard textbooks usually devote only a few pages to this topic, and this makes it difficult for clinicians not specializing in vasculitis to fully understand the pathological findings in vasculitis. To address the paucity of information, we present representative pathological findings in vasculitis classified in the 2012 Revised International Chapel Hill Consensus Conference Nomenclature of Vasculitides (CHCC2012). The CHCC2012 classifies 26 vasculitides into seven categories: (1) large-vessel vasculitis, (2) medium-vessel vasculitis, (3) small-vessel vasculitis, including antineutrophil cytoplasmic antibody-associated vasculitis and immune complex small-vessel vasculitis, (4) variable-vessel vasculitis, (5) single-organ vasculitis, (6) vasculitis associated with systemic disease, and (7) vasculitis associated with probable aetiology. Moreover, representative pathological findings of vasculitis-related diseases and non-inflammatory vasculopathy not mentioned in the CHCC2012 are also presented. This will be useful for clinicians to refer to typical pathological findings of vasculitis in daily practice.

Induced genetic ablation of Rest leads to the alteration of stimulus-induced response of the vagal nerve.

Rest (RE1-silencing transcription factor, also called Nrsf) is involved in the maintenance of the undifferentiated state of neuronal stem/progenitor cells by preventing precocious expression of neuronal genes. In order to further investigate the function of Rest in neurons, we generated and examined mice evoking genetic ablation of Rest specifically in neural tissues by generating Rest conditional knockout mice. As the Rest knockout mice are embryonically lethal, we used a Sox1-Cre allele to excise the floxed Rest gene from the early stage of nerve cell differentiation including neural crest-derived nerve cells. Using this conditional Rest knockout Sox1-Cre; Restflox/flox mice, we have revealed the role of Rest in the parasympathetic nervous system in the stomach and heart.

Gastric carcinosarcoma with FGFR2 amplification under long-term control with pazopanib: a case report and literature review.

BACKGROUND: Gastric carcinosarcoma is most frequently diagnosed at an advanced stage when the tumor is generally large with invasion into other organs, lymph node metastasis, and distant metastasis. Standard chemotherapy has not been established, and surgery is the only curative treatment. Here, we present a case of postoperative recurrence of gastric carcinosarcoma under long-term tumor control with pazopanib. CASE PRESENTATION: A 77-year-old man was referred to our hospital because of nausea and vomiting. Computed tomography and upper gastrointestinal endoscopy revealed a type 1 tumor arising from the gastric antrum and extending into the duodenal bulb. He underwent distal gastrectomy (D2) with Roux-en-Y reconstruction. Histopathologically, the tumor had mixed adenocarcinoma and sarcoma components. According to the tumor-node-metastasis classification, the diagnosis was primary gastric carcinosarcoma pT1bN1M0 stage IB. Liver metastasis was detected 2 months after surgery; multiple lung metastases were detected 17 month after surgery. A genomic profiling test was performed using liver specimens as the patient became refractory to chemotherapy commonly used for gastric cancer, and the test revealed FGFR2 amplification along with TP53 R209*, AKT3 N127D, NOTCH1 A2036T, and POLD1 M161I. The patient was treated with pazopanib (800 mg/daily), and the tumor growth was controlled for 11 months. CONCLUSIONS: We report a case of postoperative recurrence of gastric carcinosarcoma under long-term tumor control with pazopanib. This case suggested that pazopanib may be effective in treating gastric carcinosarcoma.

Poorly Differentiated Chordoma of the Clivus With Loss of SMARCB1 Expression in a Pediatric Patient: A Case Report.

Poorly differentiated chordoma (PDC) is a rare, aggressive subtype of chordoma. A two-year-old girl presented with cervical pain, limb paralysis and respiratory failure. Magnetic resonance imaging and positron emission tomography-computed tomography revealed a tumor compressing the pons at the clivus and osteoblastic metastatic lesions of the left upper arm and right iliac bone. Her tumors shrank substantially after treatment with chemotherapy and proton beam therapy. Our initial diagnosis was an atypical teratoma/rhabdoid tumor, but final diagnosis of PDC was made on the basis of the immunohistochemical expression of brachyury. In addition, the detection of SMARCB1/INI1 mutation confirmed the diagnosis of PDC.

Imaging Findings of Calcaneal Cyst and Lipoma: Can Intraosseous Cyst Changes Into Lipoma With Advancing Age?

OBJECTIVE: Recent studies have indicated that intraosseous lipomas originate from simple bone cysts of the calcaneus. This study evaluates computed tomography (CT) and magnetic resonance imaging (MRI) findings of calcaneal cysts and lipomas in pediatric and adult populations. METHODS: Forty-six patients with bone lesions located in the anterior portion of the calcaneus beneath the talocalcaneal joint, who underwent CT and/or MRI, were enrolled in this study. The imaging characteristics were retrospectively reviewed and compared between the pediatric (aged 18 years or younger; n = 29) and adult (aged 19 years or older; n = 17) groups. RESULTS: On CT images, water/soft tissue attenuation alone was more frequent in the pediatric group than in the adult group (84% vs 13%, respectively; P < 0.01), whereas the combined water/soft tissue and fat attenuation (11% vs 47%, respectively; P < 0.05) and fat attenuation alone (5% vs 40%, respectively; P < 0.05) were less frequent in the pediatric group than in the adult group. On MRI, cystic components alone were more frequent in the pediatric group than in the adult group (88% vs 13%, respectively; P < 0.01), whereas the combined cystic and fat components (8% vs 38%, respectively; P < 0.05) and fat components alone (4% vs 50%, respectively; P < 0.01) were less frequent in the pediatric group than in the adult group. CONCLUSIONS: Calcaneal cysts were more frequent in the pediatric group, whereas calcaneal lipomas were more frequent in the adult group. These results could be additional evidence that intraosseous lipomas originate from simple bone cysts of the calcaneus.

Macroscopic visible core length can predict the histological sample quantity in endoscopic ultrasound-guided tissue acquisition: Multicenter prospective study.

OBJECTIVES: Measurement of the macroscopic visible core (MVC) length during macroscopic on-site quality evaluation (MOSE) may allow estimation of sample adequacy for next-generation sequencing (NGS), and prediction of correct diagnosis in endoscopic ultrasound-guided tissue acquisition (EUS-TA) of pancreatic masses. METHODS: This multicenter prospective study included consecutive patients who underwent EUS-TA for pancreatic masses using a 22-G Franseen needle. MVC length and pathological samples obtained from two needle passes were analyzed on a per-pass basis. Outcome measures included respective correlations of MVC length with histological sample quantity and diagnostic yields. RESULTS: The analysis included 204 passes from 102 EUS-TAs. MVC length correlated positively with histological sample quantity (P < 0.01). On the receiver operating characteristic curve for MVC length, the cut-off value and area under the curve for obtaining a candidate sample for NGS were 30 mm and 0.74 (95% confidence interval [CI] 0.65-0.83), respectively. On multivariate analysis, MVC length ≥30 mm was a significant factor affecting suitability for NGS (odds ratio 6.19; 95% CI 2.72-14.10). Histologic diagnostic yield correlated positively with MVC length (P = 0.01); however, there was no positive correlation between MVC length and overall (histology plus cytology) diagnostic yield. CONCLUSIONS: Measuring MVC length to predict histological sample quantity on MOSE may be of clinical significance during EUS-TA using a 22-G Franseen needle. It may be an effective method, particularly while submitting samples for NGS. REGISTRATION: University Hospital Medical Information Network Trials Registry (UMIN000036528).

MRI findings to differentiate musculoskeletal dedifferentiated liposarcoma from atypical lipomatous tumor.

OBJECTIVE: This study aimed to assess the efficacy of using MRI findings for differentiating musculoskeletal dedifferentiated liposarcoma (DDLP) from atypical lipomatous tumor (ALT). MATERIALS AND METHODS: This study included 22 patients with histopathologically proven DDLP and 35 with ALT in the musculoskeletal areas. All DDLPs were immunohistochemically positive for MDM2. MRI findings for both pathologies were retrospectively reviewed and compared. RESULTS: The maximum lesion diameter was significantly lower in DDLPs than in ALTs (p < 0.01). Ill-defined margin, peritumoral edema, and tail sign were more frequently observed in DDLPs than in ALTs (p < 0.01, respectively). The fatty component was less frequently observed in DDLPs than in ALTs (27 vs. 100%; p < 0.01), whereas the non-fatty component was more frequently observed in DDLPs than in ALTs (100 vs. 11%; p < 0.01). The occupation rate by non-fatty components was significantly higher in DDLPs than in ALTs (p < 0.01). No significant differences were observed in imaging findings associated with fatty component; however, necrosis within the non-fatty component on the contrast-enhanced image was more frequently observed in DDLPs than in ALTs (72 vs. 0%, p < 0.05). CONCLUSION: DDLPs always had a non-fatty component, whereas ALTs always had fatty component. Ill-defined margin, peritumoral edema, tail sign, and necrosis within non-fatty components were useful MRI features for differentiating musculoskeletal DDLP from ALT.

[A Case Report of a Patient with Metastatic Adrenocortical Carcinoma who Received the Combination Etoposide, Doxorubicin, Cisplatin, and Mitotane Therapy and Achieved Remission].

A 40-year-old Japanese female was referred to our institution with a high serum lactate dehydrogenase level. Computed tomography (CT) showed a large right adrenal tumor, 14 cm in size without distant metastases. The patient was clinically diagnosed with T2N0M0 adrenocortical carcinoma and underwent right adrenalectomy. The pathological diagnosis was adrenocortical carcinoma with negative surgical margin. The patient was administered mitotane for 2 years as adjuvant therapy. Subsequently, CT revealed asynchronous multiple metastases, including liver, lung, left kidney, and right acetabulum. The patient received 15 courses of EDP (a combination of etoposide, doxorubicin, and cisplatin) plus mitotane therapy, and had stable disease without new lesions.

Diagnosis and treatment of primary central nervous system lymphoma with the primary lesion in the hypothalamus: a case report.

BACKGROUND: Primary central nervous system lymphoma is a rare extra-nodal lymphoma of the central nervous system. Primary central nervous system lymphoma lesions usually appear in the vicinity of the ventricle, and there are few reports of primary central nervous system lymphoma with hypothalamic-pituitary lesions. CASE PRESENTATION: We treated a 56-year-old male with primary central nervous system lymphoma with the primary lesion in the hypothalamus, which was found by magnetic resonance imaging after sudden onset of endocrinological abnormalities. Initially, he was hospitalized to our department for hyponatremia. Endocrinological examination in conjunction with head magnetic resonance imaging and endoscopic biopsy revealed hypothalamic hypopituitarism and tertiary hypoadrenocorticism caused by a rapidly growing, diffuse large B-cell lymphoma in the hypothalamus. Remission of the tumor was achieved by high-dose methotrexate with whole brain radiotherapy, and some of the hormone responses were normalized. CONCLUSIONS: While primary central nervous system lymphoma is rare, it is important to note that hypopituitarism can result and that the endocrinological abnormalities can be partially restored by its remission.

Magnetic Resonance Imaging Characteristics of Poroma and Porocarcinoma.

PURPOSE: The purpose of this study was to evaluate magnetic resonance (MR) imaging findings of poroma and porocarcinoma. METHODS: Six patients (3 male, 3 female; age range, 40-84 years; mean age, 61 years) with histologically confirmed skin appendage tumors with apocrine and eccrine differentiation (2 poromas and 4 porocarcinomas) were enrolled. All patients underwent preoperative MR imaging and the MR images were retrospectively reviewed. RESULTS: The configurations were classified as pedunculated solid in 5 lesions and subcutaneous cystic with mural nodules in 1. Well-demarcated deep tumor margins and smooth skin surfaces were observed in all 6 lesions, and peritumoral fat stranding was observed in 2. In all 5 pedunculated solid lesions, T2-hyperintense foci, T1 hyperintensity, and homogeneous solid components were observed within the lesions. CONCLUSIONS: Poroma and porocarcinoma usually exhibited pedunculated solid homogeneous lesion. Intratumoral T2-hyperintense foci and T1 hyperintensity were observed in pedunculated solid lesions.

Magnetic resonance imaging findings of extrauterine high-grade serous carcinoma based on new pathologic criteria for primary site assignment.

BACKGROUND: There has been no study that has reported magnetic resonance imaging (MRI) findings of extrauterine high-grade serous carcinomas (HGSCs) that have been histologically determined by the new criteria. PURPOSE: To assess MRI findings of extrauterine HGSCs based on new pathologic criteria. MATERIAL AND METHODS: Fifty patients with histopathologically proven extrauterine HGSCs, who underwent pretreatment gadolinium-enhanced MRI, were included in this study. After surgery, the primary sites were histopathologically determined based on new criteria for primary site assignment in extrauterine HGSCs as follows: fallopian tube (n = 34); ovary (n = 9); primary peritoneal HGSC (n = 1); and tubo-ovarian (n = 6). We retrospectively reviewed MR images and compared the MR findings between tubal and ovarian primaries. RESULTS: MRI patterns with tubal primaries were classified as ovarian cancer (62%), peritoneal cancer (35%), and fallopian tube cancer (3%). MRI patterns with ovarian primaries were classified as ovarian cancer (78%) and peritoneal cancer (22%). The frequency of the involvement of the fallopian tube, ovary, peritoneum, uterus, and lymph node was not significantly different between the two pathologies. There was no significant difference in the abnormal amount of ascites, hemorrhagic ascites, or characteristics of the ovarian lesions between the two pathologies. CONCLUSION: On MR images, tubal primaries almost always exhibited ovarian or peritoneal cancer pattern, but rarely exhibited fallopian tube cancer pattern. MR findings could not accurately differentiate between tubal and ovarian primaries; therefore, histopathologic investigation is essential for determination of the primary site of extrauterine HGSCs.

MR imaging findings of musculoskeletal involvement in microscopic polyangiitis: a comparison with inflammatory myopathy.

OBJECTIVE: The purpose of this study was to evaluate the importance of MR imaging findings of musculoskeletal involvement of the lower limbs in diagnosing microscopic polyangiitis (MPA) vs polymyositis (PM) or dermatomyositis (DM). MATERIALS AND METHODS: This study included 13 patients diagnosed with MPA clinically and through histologically, and 38 diagnosed with PM/DM, who underwent MR imaging of the lower limbs prior to treatment. Axial and coronal short tau inversion recovery (STIR) images were reviewed retrospectively. RESULTS: The sites affected by MPA were the lower legs in six (46%) patients and the thighs in seven (54%). Intramuscular hyperintensity and fascial hyperintensity were observed in all cases of MPA (100%). Fascial hyperintensity was more frequently encountered in MPA than in PM/DM (100% vs. 45%, p < 0.01). As the predominantly involved sites, the fascial regions were more frequently affected by MPA than by PM/DM (77% vs. 18%, p < 0.01). Diffuse subcutaneous fat hyperintensity was more frequently observed in MPA than in PM/DM (100% vs. 16%, p < 0.01). However, no significant differences in intramuscular hyperintensity (100% vs. 97%, p = 0.745) and subcutaneous fat hyperintensity (54% vs. 50%, p = 0.533) were found between MPA and PM/DM. CONCLUSION: Intramuscular hyperintensity and fascial hyperintensity have always been observed in MPA, and the predominantly affected sites were usually the fascial regions. Compared with PM/DM, fascial hyperintensity and diffuse subcutaneous fat hyperintensity were more frequent in MPA.

Solitary Fibrous Tumor of the Prostate: A Case Report and Literature Review.

Solitary fibrous tumors (SFTs) usually occur in the pleura and account for two-thirds of all cases; however, SFTs occurring in the prostate are extremely rare. Approximately 25 cases have been reported in the literature to date. This study reports the case of a 43-year-old man referred to our hospital with the chief complaint of a pelvic tumor after careful examination. The tumor marker levels were within normal limits. T2-weighted magnetic resonance imaging revealed a tumor, demonstrating primarily low signal intensity. It showed a capsule-like rim at the left lobe of the prostate, suggesting that the tumor was partially invading the rectal wall. Histopathological examination of needle-core biopsies showed spindle cell neoplasm with small and fusiform cells, strongly expressing signal transducer and activator of transcription 6 (STAT6) with a ramifying vascular network. Therefore, the clinical diagnosis of the patient was SFT of the prostate and robot-assisted radical prostatectomy was performed. Histopathological examination revealed that the tumor was composed of spindle cells with patternless and staghorn patterns. Immunohistochemical analysis showed a strong expression of STAT6. Furthermore, the tumor was partially positive for CD34. Therefore, the patient was diagnosed with SFT of the prostate. Two years after the initial diagnosis, the patient was alive with normal erectile function, continence status, and no evidence of the disease.

[Renal Cell Carcinoma in the Left Pelvic Kidney : A Case Report].

We report the case of a 61-year-old man who was incidentally diagnosed with a left pelvic ectopic kidney with renal tumor. Computed tomography showed a hypervascular tumor at the posterior surface of the ectopic kidney with five arterial and two venous supply vessels. On preoperative examination, this patient had respiratory dysfunction. For these reasons, an open radical nephrectomy was performed. Histological examination revealed a clear cell renal cell carcinoma, pT1aN0M0, G1, and a Fuhrman nuclear grading system grade of G2. No evidence of disease was observed 15 months after surgery.

[Paraurethral Leiomyoma in a Female Patient who Had Clinical Symptoms with Increase of Tumor Volume: A Case Report].

A 34-year-old woman underwent total hysterectomy for management of uterine leiomyoma. At the same time, a paraurethral tumor (2 cm in size) was diagnosed based on magnetic resonance imaging (MRI). However, the patient was not treated for the tumor considering its small size. Eight years later, the patient was referred to our institution with a chief complaint of urethral bleeding. Computed tomography revealed a paraurethral mass at the same location, which was 13 cm in size. A percutaneous needle biopsy was performed and the tumor was diagnosed as leiomyoma. Tumor extirpation was performed and immunohistochemical analysis of the specimen demonstrated positive estrogen and progesterone receptors. Recurrence was not observed on MRI taken 6 months after the surgery. Paraurethral leiomyoma is rare, but relatively common in young women.