A large cystic phyllodes tumor of the prostate

Mesenchymal Neoplasms of the Prostate and Seminal Vesicles: Spectrum of Disease with Radiologic-Pathologic Correlation

There is a wide spectrum of benign and malignant mesenchymal neoplasms of the prostate, which account for less than 1% of all prostatic tumors. These include distinctive tumors that arise from the specialized prostatic stroma and site-agnostic neoplasms such as smooth muscle tumors, fibrous or myofibroblastic neoplasms, neurogenic tumors, vascular tumors, and a plethora of sarcomas. Select tumors show classic sites of origin within the prostate. While stromal tumors of uncertain malignant potential (STUMPs) commonly involve the peripheral zone at the prostate base, leiomyomas typically originate from the central prostate toward the apex. Some "prostatic" neoplasms such as gastrointestinal stromal tumors, solitary fibrous tumor (SFT), paragangliomas, and neurogenic tumors arise primarily from periprostatic soft tissues. Most mesenchymal tumors of the prostate and seminal vesicles manifest as large tumors that cause nonspecific symptoms; prostate-specific antigen level is not typically elevated. Diverse mesenchymal neoplasms demonstrate characteristic histopathologic and immunocytochemical features and variable cross-sectional imaging findings. While leiomyoma and SFT typically display low signal intensity on T2-weighted images, synovial sarcomas commonly show hemorrhage. Diagnosis is difficult because of the rarity and lack of awareness of the tumors and the significant overlap in histopathologic features. Select tumors show characteristic genetic abnormalities that allow the diagnosis to be established. For example, more than 90% of SFTs are characterized by a unique NAB2-STAT6 gene fusion, and more than 95% of synovial sarcomas are associated with a distinctive SYT-SSX chimeric transcript. Accurate diagnosis is imperative for optimal management owing to markedly different tumor biology as well as attendant therapeutic and prognostic implications. While STUMPs commonly recur, sarcomas typically charter an aggressive course with poor prognosis. Online supplemental material is available for this article. ^©RSNA, 2022.

Onset of hydronephrosis and lower urinary tract symptoms in a previously healthy young man: Phyllodes tumour of the prostate as a potential diagnosis

We report the case of a 50-year-old healthy man with early onset of micturition symptoms associated with an elevated total prostate-specific antigen. On physical examination, we found an enlarged prostate; a first-line ultrasound of the urinary tract revealed local disease which covered the entire small pelvis. A computed tomography scan confirmed the presence of a 12.5 × 11.0 × 9.5-cm multicystic prostatic mass, compressing the bladder and pelvic ureters, associated with right hydronephrosis. Renal function was preserved and prostatic biopsies was negative for malignant disease. The mass was completely removed through transvesical approach and histological analysis diagnosed a low-grade phyllodes tumour of the prostate. The patient was free of local recurrence and metastasis 36 months after surgery.

Prostate cancer with cyst formation detected by whole body positron emission tomography/computed tomography: A case report

The present study reports a case of prostate adenocarcinoma with cyst formation. A 72-year-old male diagnosed with multiple lung metastases at a local clinic was referred to Tokai University Hachioji Hospital (Tokyo, Japan) for detection of a primary lesion. Whole body positron emission tomography/computed tomography showed strong accumulation of [¹⁸F]-fluoro-deoxy-2-glucose (FDG) in the small pelvis, and pelvic magnetic resonance imaging revealed a 60×40-mm cystic lesion, with an irregular thickened wall, behind the prostate. The serum prostate-specific antigen (PSA) level was elevated to 211.99 ng/ml, therefore, the patient underwent a transperineal prostate needle biopsy, and was diagnosed with prostate adenocarcinoma with cyst formation. Androgen deprivation therapy was administered for 8 months following the diagnosis of prostate cancer; consequently, the cyst reduced in size and the serum PSA level decreased to 0.14 ng/ml. To the best of our knowledge, this is the first report of a malignant prostatic cyst detected by FDG-positron emission tomography/computed tomography.

Giant multicystic cystadenoma of Cowper's gland: a case report

MAIN FINDINGS

We report what to our knowledge is the first case of a giant multicystic cystadenoma of the Cowper's glands. An otherwise healthy 41-year-old man presented with acute urinary retention. Physical examination showed a perineal mass. Different imaging techniques demonstrated a multicystic tumor and en bloc excision was performed. Histological evaluation showed that the tumor arised from the bulbourethral glands; immunohistochemistry proved positive staining for high molecular weight cytokeratin. CASE HYPOTHESIS: Cystic tumors in the pelvis can arise from different structures. Malignancy should be ruled out. Surgical excision can be diagnostic and curative. Future implications: When evaluating a pelvic cystic tumor, Cowper's glands cystadenoma may be a differential diagnosis and must be considered. Similar to prostate cystadenomas, en bloc excision is the optimal treatment.

Prostatic stromal neoplasms: differential diagnosis of cystic and solid prostatic and periprostatic masses

OBJECTIVE

The objectives of this article are to illustrate the radiologic-pathologic correlation of prostate stromal neoplasms and to review the imaging appearances of cystic and solid prostatic and periprostatic masses that may mimic prostatic stromal neoplasms.

CONCLUSION

The differential diagnosis for cystic and solid masses in the prostate is broad, and masses arising from periprostatic structures may mimic the appearance of primary prostatic diseases. Attention to clinical and imaging features is helpful in narrowing the differential diagnosis.