Radiology-pathology conference: malignant solitary fibrous tumor of the seminal vesicle

Intense PSMA Uptake in Solitary Fibrous Tumor of the Seminal Vesicle

ABSTRACT

Solitary fibrous tumor arising from the seminal vesicle is very rare. We describe 18 F-PSMA-1007 PET/CT findings in a case of prostate adenocarcinoma with a solitary fibrous tumor of the left seminal vesicle. The solitary fibrous tumor showed intense 18 F-PSMA-1007 uptake mimicking metastatic prostate adenocarcinoma. This case indicates that solitary fibrous tumor may cause false-positive result when using PSMA PET in staging of prostate cancer.

Incidental solitary fibrous tumor involving the seminal vesicle: A case report

Solitary fibrous tumors are rare mesenchymal neoplasms that can range from slow-growing to aggressive tumors. This report presents a unique case of a young male patient with a solitary fibrous tumor involving the seminal vesicle, a rare location, and reinforces incidental discovery of these tumors on imaging and physical exams. Detection of these tumors is imperative to identify and treat malignancy. In our case, a 39-year-old previously healthy Asian male presents to the emergency department as a trauma admission post bicycle crash and is incidentally found to have a pelvic mass on computed tomography imaging of the pelvis. The patient underwent trans-anal biopsy which showed spindle epithelioid cells positive for CD34 and STAT6 markers, with a morphological and immunohistochemical profile consistent with a solitary fibrous tumor. The patient underwent surgery with a robotic-assisted laparoscopic pelvic mass resection and now follows up annually with imaging for observation.

Solitary Fibrous Tumor of the Seminal Vesicle: A Systematic Literature Review and Case Presentation

BACKGROUND/AIM

Solitary fibrous tumors (SFTs) are ubiquitous mesenchymal neoplasms that have an unpredictable biological behavior. Histological criteria for this type of malignancy are uncertain. Clinical characteristics, diagnostic and treatment options of SFTs originating in the seminal vesicle are presented in this review article.

MATERIALS AND METHODS

A systematic review including the following databases: Scopus, Embase and Medline from 1960 until the end of March 2021 was performed according to the Preferred Reporting Items for Systematic Reviews (PRISMA) guidelines.

RESULTS

We found seven patients affected with SFTs of seminal vesicle, in which we added our own case, making a total of 8 patients. Mean age at presentation was 55±7 years. Mean size of the SFTs was 9±2 cm and the right seminal vesicle was preferentially involved. The majority of patients were symptomatic and presenting symptoms were hematuria, dysuria, hematospermia, urinary increased frequency and urgency. Abdominal ultrasonography, computed tomography (CT) scan, and magnetic resonance (MRI) were the diagnostic tools. Trans-rectal ultrasound-guided core biopsy was also used. Seven (87%) patients had open surgery. Adjuvant radiotherapy after R0 resection was used in 1 patient.

CONCLUSION

The treatment of SFTs located in the seminal vesicle necessitates a radical surgical resection to obtain acceptable results in terms of local recurrence and distant metastases.

Solitary fibrous tumor of the seminal vesicle: A case report

RATIONALE

Solitary fibrous tumor (SFT) is an unusual neoplasm, especially when it originates from the seminal vesicle. Herein, we describe a case of SFT that arises from the seminal vesicle.

PATIENT CONCERNS

A 66-year-old man presented to our hospital complaining of a huge irregular tumor in his pelvis during a health checkup. He was worried that the tumor could be a malignant tumor and hence wanted to undergo further examination and therapy.

DIAGNOSIS

An inhomogeneous, mixed soft tissue tumor in the pelvis was found during computed tomography (CT) and magnetic resonance imaging. The tumor showed heterogeneous and delayed enhancement during contrast-enhanced CT. The tumor was diagnosed as a cystadenoma originated from the seminal vesicle due to its imaging features. But the pathological diagnosis was SFT that originated from the seminal vesicle.

INTERVENTIONS

Laparoscopic seminal vesicle tumor resection was performed.

OUTCOMES

There was no evidence of recurrence at the 6-month follow-up.

LESSONS

SFT in the seminal vesicle is extremely rare. It is very difficult to distinguish SFT in the seminal vesicle from the primary tumors as both have similar imaging features. We describe the tumor with SFT being considered as a differential diagnosis when the tumor is found in the seminal vesicle.

Solitary Fibrous Tumors: 2016 Imaging Update

Optimal management of solitary fibrous tumor requires a multidisciplinary approach with proper histopathological mapping and use of various imaging modalities for exact delineation of primary tumor and metastatic disease if present. In this article, the authors present a comprehensive review of the spectrum of imaging findings of solitary fibrous tumors involving various organ systems and discuss the role of molecular targeted therapies in the management of metastatic disease.

Variable Solitary Fibrous Tumor Locations: CT and MR Imaging Features

The aim of the study is to describe the radiological imaging features of different solitary fibrous tumors (SFTs) locations and present histopathological correlations. From 2007 to 2013, 20 cases of histologically confirmed that SFTs were retrospectively analyzed with computed tomography (CT; 9/20), magnetic resonance imaging (MRI; 5/20), or both CT and MRI (6/20). All 20 SFTs were well defined, lobular, soft-tissue masses, and 60% were located outside of the pleura. One pleural case invaded to the 10th thoracic vertebra and had lung metastases. Images revealed 11 heterogeneous lesions that exceeded 3.0 ± 0.203 cm along the greatest axis with patchy necrotic foci, and 9 homogeneous lesions <3.0 ± 0.203. Microscopically, all SFTs were proliferative spindle cells with varying degrees of fibrosis and interspersed vessel branching. Cells were strongly immunopositive for CD34. Here we review variable imaging findings of SFTs, which can be within the pleura as well as within other serosal tissues such as the meninges and postperitoneum. SFTs > 3.0 ± 0.203 cm along the greatest axis appeared to be mixed patterns, whereas SFTs < 3.0 ± 0.203 cm had isodense appearances. SFTs cells were CD34 immunopositive and surgery was a first-line treatment choice.

MRI findings of solitary fibrous tumours in the head and neck region

OBJECTIVES

To analyse the MRI findings of solitary fibrous tumours in the head and neck region.

METHODS

We retrospectively reviewed MR images in eight patients with solitary fibrous tumours proven on histological examination. All the patients underwent conventional MRI, and four patients also underwent dynamic contrast-enhanced MRI and diffusion-weighted imaging in five cases. Image characteristics were analysed.

RESULTS

All lesions were found as solitary well-defined masses ranging in size from 1.9 to 6.8 cm (mean, 4.1 cm). They were mostly homogeneous and isointense to the muscle on T1 weighted images and heterogeneous and mildly hyperintense on T2 weighted images. After gadolinium administration, areas that were mildly hyperintense on T2 weighted images were strongly enhanced. They were mildly hyperintense on diffusion-weighted imaging. The average tumour-apparent diffusion coefficient values were 0.001 157 ± 0.000 304 9 mm s(-2) compared with the muscle 0.000 760 ± 0.000 265 0 mm s(-2), and there was a statistical difference of p = 0.002. The time-intensity curves exhibited a rapidly enhancing and a slow washout pattern on dynamic contrast-enhanced MRI.

CONCLUSIONS

Solitary fibrous tumours should be considered in cases of heterogeneous hypervascular tumours in the head and neck region. Areas of mild hyperintense intensity on T2 weighted images that are strongly enhanced after gadolinium injection are suggestive of this diagnosis. Non-restricted diffusion and rapidly enhancing and slow washout pattern time-intensity curves may be additional valuable features.