Solitary Fibrous Tumor of the Prostate

A case report and literature review on primary solitary fibrous tumor of the bladder

RATIONALE

Solitary fibrous tumors (SFT) is a rare mesenchymal tumor originating from a CD34-positive dendritic mesenchymal cell, most of which is benign, the most common sites is pleura and mediastinum, and rarely in the bladder. The clinical manifestations are mainly related to the tumor volume. When the tumor volume is large, it will compress the surrounding tissues or organs and cause corresponding symptoms. Laparoscopic Incision biopsy is effective means for diagnosing SFT.

PATIENT CONCERNS

A 70-year-old female patient was admitted to the hospital with a bladder neoplasm detected by computed tomography scan after experiencing intestinal obstruction 3 days following esophageal cancer surgery. She denied any history of tumor disease.

DIAGNOSES

No abnormality was found in the physical examination and laboratory testing after admission. Ultrasound imaging showed a large solid mass with low echogenicity in the bladder. Urological computed tomography with 3D reconstruction revealed a large cystic-solid mass located on the right wall of the bladder, measuring approximately 6.8 cm × 7.1 cm × 6.5 cm, with uneven density and mild inhomogeneous enhancement after contrast administration. Cystoscopy revealed a large mucosal bulge on the right wall of the bladder and laparoscopic exploration revealed a smooth-surfaced round mass, approximately 7 cm in size.

INTERVENTIONS

Incision biopsy was performed to make a clear diagnosis, and appropriate tissue specimens were obtained for pathological testing.

OUTCOMES

The patient was diagnosed as SFT according to pathology. The patient was followed up for 6 months after surgery, and no recurrence was observed.

LESSONS

SFT occurring in the bladder are extremely rare, and the site is scarcely reported in the relevant literature; thus, it is easy to misdiagnose and laparoscopic incision biopsy may be a good choice.

Solitary fibrous tumors in prostate: a case report with review of the literature

BACKGROUND

Solitary fibrous tumor (SFT) is a relatively rare type of mesenchymal neoplasm that occurs most frequently in the pleura. However, SFT originating from the prostate is particularly uncommon and only approximately 39 cases were reported before. Herein, we reported a rare case of a patient diagnosed with prostate SFT and presented a literature review.Case presentation: A 50-year-old Asian with irritative urinary symptoms was admitted to our hospital and almost all the evidence indicated that benign prostate hyperplasia (BPH) caused his symptoms. Therefore, transurethral resection of the prostate (TURP) was performed, but histopathological and Immunohistochemical (IHC) assessments showed that spindle cells arranged disorderly in the TURP specimen with a cluster of differentiation 34 (CD34), B-cell lymphoma-2 (Bcl-2), and signal transducer and activator of transcription 6 (STAT6) highly expressed and SFT was diagnosed. Finally, the patient underwent a radical prostatectomy and there was no disease progression observed thereafter.

CONCLUSIONS

Prostate SFT is extremely rare, and to our knowledge, this is the first case of prostate SFT that is difficult to differentiate from small volume BPH. IHC examinations are of great diagnostic value. Radical resection of the tumor appears to be the most effective method at present and continuous follow-up is highly recommended.

Rapidly growing solitary fibrous tumors of the pleura: a case report and review of the literature

A solitary fibrous tumor (SFT) is a rare spindle cell tumor-derived from mesenchymal cells. It may be linked to the fusion of the NAB2-STAT6 gene caused by 12q chromosome rearrangement. It can occur in the connective tissue of any part of the body; however, it is most common in the pleura. Solitary fibrous tumors of the pleura (SFTP) are a persistent painless mass with slow growth. With the increase of the tumor, there will be corresponding compression symptoms. Pleural effusion is rare, and the cytology of pleural effusion is mostly negative. Occasionally, SFTP can induce paraneoplastic syndrome, distant metastasis, and malignant transformation. Lung function may have mild to moderate restrictive ventilation dysfunction. CT is a crucial method for the clinical diagnosis of SFTP. The histopathological features of SFTP are the coexistence of sparse and dense areas. CD34, CD99, Bcl-2, and vimentin are the most valuable immunohistochemical markers.The positive expression rate of STAT6 in benign SFT was even 100%. Adhesion or unclear boundary with surrounding tissues, pleural effusion or calcification, tumors with a maximum diameter greater than 10 cm, invasive growth, uneven density, metastasis or recurrence, paraneoplastic syndrome, moderate to severe cell heterogeneity, high Ki67 proliferation index, and low STAT6 expression suggest SFTP may be a malignant tumor. Gene analysis on next generation sequencing may help reveal the mutation characteristics of SFTP. Complete tumor resection is the gold standard of SFTP. Resectability is the most important prognostic factor. Age, size, mitosis, and necrosis are considered risk stratification factors for prognosis. Fortunately, 80% of SFTP are benign and have anexcellentprognosis but need long-term follow-up.We report a case of rapidly growing tumor with pleural effusion within 9 months, who was surgically treated and is currently under follow-up. And the literature is reviewed.