Benign perivascular myoid cell tumor (myopericytoma) of the urinary tract: a report of 2 cases with an emphasis on differential diagnosis

Renal myopericytoma: A case report with a literature review

Myopericytoma is a rare soft tissue tumor characterized by differentiation into perivascular muscle-like cells or perimuscular cells. This tumor primarily affects adults and is uncommon in children. It is predominantly found in the subcutaneous soft tissues of the distal limbs, and cases originating in the kidney are exceedingly rare. In this report, we present a case of a patient with renal myopericytoma admitted to our hospital. We also summarize the diagnostic and therapeutic features by reviewing relevant domestic and international literature.

Myopericytoma in the corpus cavernosum of the penis: A case report of a rare disease

Introduction

Myopericytomas usually occur in the extremities of older individuals; however, they also rarely occur in the penis. We report a case of myopericytoma in the corpus cavernosum of the penis and review the relevant literature.

Case presentation

A 76-year-old man presented with a slow-growing painless nodule on the left side of the penis. On physical examination, a non-tender, 7-mm mass was palpable. This tumor showed inhomogeneous low signal intensity on T2-weighted magnetic resonance imaging. The mass was excised and a myopericytoma diagnosed by pathological examination of the operative specimen.

Conclusion

We here report a rare case of myopericytoma in the corpus cavernosum of the penis. To the best of our knowledge, this is the second reported case of a myopericytoma in the penis and the first in the corpus cavernosum of the penis. Clinicians should keep this rare possibility in mind when investigating a mass in the penis.

Primary hepatic myopericytoma coexisting with multiple cystic hepatic lesions: a case report

BACKGROUND

Hepatic myopericytoma (MPC) is an extremely rare pathological entity in the liver. Conversely, cystic hepatic lesions are a group of heterogeneous lesions encountered commonly in daily practice. Here, we report a unique case of the coexistence of primary hepatic MPC and multiple cystic hepatic lesions along with our perceptions on its diagnosis and treatment.

CASE PRESENTATION

A 56-year-old female patient was found to have a left liver mass during a routine physical examination. Computer tomography (CT) and magnetic resonance imaging (MRI) confirmed the existence of a left hepatic neoplasm along with multiple hepatic cysts but could not exclude the possible malignant nature of the neoplasm. Computer tomography (CT) also identified an enlarged mediastinal lymph node with a maximum diameter of 4.3 cm, which further underwent core needle biopsy under CT guidance. A histopathological examination was performed to rule out malignancy. Afterwards, the patient underwent left hemihepatectomy to resect a solid tumor of 5.5 cm × 5 cm × 4.7 cm with multiple cystic lesions which were histopathologically examined to establish the diagnosis of myopericytoma with hepatic cysts. Postoperatively, the patient recovered from the surgery quickly without significant adverse events and was not found to have a reoccurrence of the primary pathological entity.

CONCLUSIONS

This is the first reported case of a patient with the co-existence of primary hepatic myopericytoma and multiple cystic hepatic lesions undergoing surgical treatment with eventual recovery.

Rare Case of Intravascular Myopericytoma-Imaging Characteristics and Review of the Literature

Myopericytoma is a rare vessel wall tumor, a subtype of hemangiopericytoma that usually develops subcutaneously. Intravascular myopericytoma is a rarer subtype, with only few cases reported in the literature and even fewer with imaging modalities included. We report the case of a 36-year-old man who was referred to our institution with a painless, palpable mass in the right arm and was evaluated with MRI, grey-scale and Doppler-mode ultrasound. Tumor histopathology and imaging characteristics are presented together with the role that each imaging modality played in the management of the patient.

A retroperitoneal myopericytoma: The first case located at the retroperitoneal area and not originate from the kidneys

A 25-year-old woman had a mass of approximately 65 cm × 33 cm × 102 cm, located in the left paraaortic area on CT scan. It was diagnosed as retroperitoneal malignant neoplasm on imaging. Afterward, open retroperitoneal tumor excision was performed. At laparotomy, the mass was carefully dissected from the ureter, renal artery, and aorta and excised as en-bloc. The pathological result was "myopericytoma." Histologically, the pathological findings characterized a pericytic neoplasm characterized by a perivascular growth of myoid tumor cells. In addition, there were uniform, oval-shaped cells with eosinophilic cytoplasm arranged in short fascicles around blood vessels. The cytologic atypia and mitoses were absent. There are many different tumors in the retroperitoneal area. Most of these lesions are malign nature. Nevertheless, for each benign and malign neoplasm, the preoperative imaging method is generally similar. This present case showed the significant findings of myopericytoma, a benign pathology located in the retroperitoneal area.

Renal myopericytoma: A case report and literature review

Renal myopericytoma is an extremely rare entity with just 11 cases reported in the literature. We report the case of a 57 year old Caucasian man who was found to have a renal myopericytoma following nephrectomy for suspected renal cell carcinoma. Renal myopericytoma has a distinct morphological overlap with other pericytic tumours and significant histological variation has been noted between cases reported to date. Further characterising this novel tumour is vital to identify subtypes within this spectrum, understand its behaviour and to identify imaging trends which may lead to pre-operative diagnosis in order to potentially avoid radical treatment.

Imaging performance and preoperative differential diagnosis of multiple myopericytoma in the liver: A case report

Myopericytoma is a rare type of benign tumor, which commonly affects all four limbs. The occurrence of myopericytoma in the liver is extremely rare. Myopericytoma with a size of >1 cm in diameter in the liver has not been previously reported. Due to the limited number of cases, the preoperative diagnosis of liver myopericytoma based on laboratory and imaging examinations is difficult. In the present case report, a patient with multiple myopericytoma in the liver, with a maximum diameter of 4.5 cm was described, with accompanying computed tomography (CT) and positron emission tomography/CT (PET/CT) imaging profiles. The aim of the present report was to discuss the preoperative differential diagnosis between myopericytoma and other common liver neoplasms, such as intrahepatic cholangiocarcinoma or liver metastasis.

Clinico-pathological features of gynecological myopericytoma: a challenging diagnosis in an exceptional location

Myopericytomas (MPC) are rare mesenchymal tumors, originating from the perivascular myoid cells. They predominantly occur in the skin and superficial soft tissues of the extremities, while visceral involvement is rare. Histological features and clinical course are usually benign. To the best of our knowledge, MPC is still an uncharacterized tumor entity of the female internal genital tract. We describe three MPC cases involving the female internal genital tract: (1) a uterine wall MPC arising in a 49-year-old woman with progressive pelvic/abdominal pain; (2) a cervix MPC of a 49-year-old woman who presented with metrorrhagia, and (3) a MPC presenting as a simple ovarian cyst in a 26-year-old woman with pain located in the left iliac fossa. All patients were surgically treated, and recurrence occurred in two cases. The histological and immunohistochemical findings, supporting the diagnosis of MPC, are presented; in particular, one case showed characteristics pointing towards an uncertain biological behavior/low-grade malignancy. A literature search was conducted to identify previous reports of gynecological MPC and for possible alternative diagnoses. Leiomyoma, epithelioid leiomyoma, angioleiomyoma, perivascular epithelioid cell tumor, solitary fibrous tumor, and low-grade endometrial stromal sarcoma should be considered in the differential diagnosis. Awareness of possible occurrence of this rare neoplasm in the female genital tract is important to reach a correct diagnosis in the spectrum of mesenchymal tumors. Considering the risk of recurrence, we recommend careful evaluation of surgical margins and complete surgical removal whenever possible.

Mesenchymal Neoplasms of the Genitourinary System: A Selected Review with Recent Advances in Clinical, Diagnostic, and Molecular Findings

Mesenchymal neoplasms of the genitourinary (GU) tract often pose considerable diagnostic challenges due to their wide morphologic spectrum, relative rarity, and unexpected incidence at GU sites. Soft tissue tumors arise throughout the GU tract, whether from adventitia surrounding or connective tissues within the kidneys, urinary bladder, and male and female genital organs. This selected article focuses on a subset of these lesions, ranging from benign to malignant and encompassing a range of patterns of mesenchymal differentiation, where recent scholarship has lent greater insight into their clinical, molecular, or diagnostic features.

Foot soft tissue myopericytoma: Case-report and review

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Myopericytoma is a rare tumor of deep soft tissues.

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Small tumefying at the level of the plantar region, between the 2nd and 3rd toe of the right foot.

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Neoformation of 0.6 cm in diameter, well circumscribed, capsulated and with free resection margins.

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The immunohistochemical profile was consistent for positive alpha-actin and negative desmine.

Introduction

Myopericytoma is a rare tumor of deep soft tissues, originating from pericytes and characterized by numerous thin walled blood vessels.

Case report

We report a case of myopericytoma found at the level of the second toe of the right foot.

A patient came to the Endocrinology Surgery Department of Catania Polyclinic because of a presence of a small swelling in the plantar region, between the 2nd and 3rd toe of the right foot. At the anatomopathological examination, the escalated lesion showed a neoformation of 0.6 cm in diameter, well circumscribed, capsulated, with myopericytoma diagnosis.

Discussion

Its histopathological appearance is similar to myofibromatic lesions from glomic and angiomyoma tumors. It is a rare tumor that affects all ages with a peak after 50 years 3. The most frequent localization is at the lower extremities, particularly in soft subcutaneous tissues, but can rarely occur in other sites.

Conclusion

At the anatomopathological evaluation, the immunohistochemical examination for the correct formulation of the diagnosis is essential and an adequate surgical excision is important.

Myopericytoma occurrence in the liver and stomach space: imaging performance

BACKGROUND

Myopericytoma is a rare and usually benign tumor, which is even rarer if it occurs in the liver and stomach space. Previous reports of myopericytoma were mostly related to its pathological manifestations, while imaging reports were rare. Here, we report the computed tomography (CT), computed tomography angiography (CTA) and magnetic resonance imaging (MRI) performance for one deep myopericytoma.

CASE PRESENTATION

In this study, one deep myopericytoma in the liver and stomach space is reported. A CT that was not contrast-enhanced showed a lobulated tumor with heterogeneous density, and a contrast-enhanced CT showed that the mass had progressive enhancement. CTA showed that the blood-supply of the tumor was supplied by the anterior superior pancreaticoduodenal artery and the left gastric artery. An MRI showed the lesion had isointensity on T1-weighted imaging (T1WI) and slight hyperintensity on T2-weighted imaging (T2WI). The lesion MRI enhancement characteristics were similar to the characteristics from the contrast-enhanced CT. In this case, the enhancement pattern of the tumor was the centrifugal enhancement for both the contrast-enhanced CT and MRI. After surgical resection of the tumor, the pathological diagnosis was myopericytoma, and there was no recurrence in a short-term follow-up.

CONCLUSION

The myopericytoma generally has a rich blood supply. When there is necrosis in the center lesion, the lesion has peripheral enhancement. Abdominal myopericytoma could be categorized as having centrifugal enhancement.

Myopericytoma in urinary bladder: a case report

BACKGROUND

Myopericytoma is reported to occur mainly in the skin and superficial soft tissue of the extremities. In contrast, occurrence in the urinary bladder is extremely rare.

CASE PRESENTATION

We describe a 75-year-old Japanese man who developed a submucosal tumor at the right trigone of his bladder that led to interference with the discharge of right ureteral calculus. No invasive growth was observed by magnetic resonance imaging. Transurethral resection was successfully performed; histopathological analysis revealed perivascular proliferation of spindle-shaped to oval-shaped, cytologically bland tumor cells with eosinophilic cytoplasm. On immunohistochemical examination, the tumor cells were positive for alpha-smooth muscle actin, desmin, CD34 and h-caldesmon.

CONCLUSION

Cystoscopic and pathological findings were compatible with a diagnosis of myopericytoma of the urinary bladder.

Overexpression of caldesmon is associated with tumor progression in patients with primary non-muscle-invasive bladder cancer

The expression and function of caldesmon (CAD) in urothelial bladder carcinoma (BC) have not been reported. Here, we investigated the expression, prognostic value, and potential functional mechanism of CAD in primary non-muscle-invasive bladder cancer (NMIBC). Protein profiling of tissue samples using antibody microarrays showed significantly higher CAD expression in muscle-invasive BC tissues compared with NMIBC tissues. We then validated the CAD expression in BC cells by immunohistochemistry analysis using paraffin-embedded tissue blocks and western blots using BC cell lines. In addition, we examined the expression of CAD variants by reverse transcription-polymerase chain reaction, and confirmed the expression of low-molecular-weight isoforms (L-CAD), specifically encoded by WI-38 L-CAD II (transcript variant 2), in BC cells. Survival analysis in an independent primary NMIBC cohort comprising 132 patients showed that positive CAD expression was significantly associated with poorer prognosis than no CAD expression with regard to recurrence- and progression-free survival (p = 0.001 and 0.014, respectively). Multivariate analyses further indicated that positive CAD expression was an independent predictor of progression-free survival (p = 0.032; HR = 5.983). Data obtained from in vitro silencing and overexpression studies indicated that L-CAD promotes migration and invasiveness of BC cells. Immunofluorescence assays showed dramatic structural changes in the actin cytoskeleton of BC cells after L-CAD overexpression. Our findings collectively suggest that L-CAD overexpression in primary NMIBC is significantly associated with tumor progression and that a possible mechanism for L-CAD's activity is implicated in increased cell motility and invasive characteristics through morphological changes in BC cells.

[Mesenchymal tumors of the urinary bladder]

Mesenchymal tumors and tumor-like lesions of the urinary bladder are rare. They encompass a heterogeneous group of reactive pseudosarcomatous tumor-like changes and benign neoplastic lesions as well as malignant neoplasms (sarcomas) with variable biological behavior. The well-known differential diagnostic difficulties related to these conditions are mainly due to their rarity and thus limited experience and familiarity with their histological features and due to the significant morphological overlap between fully benign reactive conditions and aggressive malignant neoplasms. The distinction between them may on occasion represent a real challenge and is associated with several pitfalls. This overview summarizes the clinicopathological and differential diagnostic aspects of the most important lesions and discuss their differential diagnosis in the light of current knowledge.