Ductal adenocarcinoma of the prostate associated with prostatic multilocular cyst

Magnetic resonance imaging findings of pure prostatic ductal adenocarcinomas: a case series

PURPOSE

This study aimed to investigate the characteristics of magnetic resonance imaging (MRI) findings in pure prostatic ductal adenocarcinoma.

METHODS

From January 2009 to February 2020, seven patients who were diagnosed with pure prostatic ductal adenocarcinoma and had a referable preoperative MRI scan were included in the study. We evaluated the following MRI findings for each tumor: size, location, presence of multi-cystic component, and apparent diffusion coefficient (ADC) value.

RESULTS

The median maximum diameter of the tumors was 22 mm (range 19-70 mm). Regarding transverse distribution, five tumors were located in the periurethral area and two were located peripherally apart from the urethra. Two of the seven tumors had cystic components. The median ADC value of the tumors was 0.754 × 10^-3 mm²/s (range 0.570-0.963 × 10^-3 mm²/s). Based on the transverse distribution and components of the tumors on MRI, ductal adenocarcinomas were classified into three types: type I as a non-cystic tumor located peripherally apart from the urethra (29%, two cases); type II as a non-cystic tumor located in the periurethral area (43%, three cases); and type III as a tumor with a multi-cystic component (29%, two cases).

CONCLUSION

The non-cystic mass with periurethral distribution (type II) and multi-cystic mass (type III) may be characteristic features that differentiate pure ductal adenocarcinoma from ordinary acinar adenocarcinoma on MRI.

MRI Finding of Prostatic Ductal Adenocarcinoma

Ductal adenocarcinoma is a variant of prostatic adenocarcinoma, originating from the epithelial lining of the primary and secondary ducts of the prostate. We report a 63-year-old male with prostatic ductal adenocarcinoma, presenting as urinary retention and a prostate-specific antigen (PSA) level of 11.71 ng/mL and biopsy-proven prostate cancer (Gleason score 3 + 3). MRI showed 2 hemorrhagic, multilocular cysts projecting into the bladder side from the prostatic inner gland and between the prostate and the right seminal vesicle. The prostate inner gland showed high signal intensity on the T2-weighted image and included tiny hyperintense spots on the fat-suppression T1-weighted image. In the part of the border of the hemorrhagic, multilocular cyst, a solid portion showing slight low intensity on T1-weigthed imaging and markedly restricted diffusion was observed, suggesting prostate cancer. He underwent total prostatectomy, and ductal adenocarcinoma (Gleason score 4 + 4) in the prostate inner gland and multilocular cysts was pathologically diagnosed. After the operation, his PSA level gradually increased, and MRI 8 months after the operation showed a vesical multilocular cyst, suggesting local recurrence. After he underwent radiation therapy and hormonal therapy, PSA level decreased, and no re-recurrence was observed during 8 years. We suggest its inclusion in the differential diagnosis of cases of prostatic ductal adenocarcinoma's multiloculated cystic formation around the prostate and the bladder.

Differential diagnosis of uncommon prostate diseases: combining mpMRI and clinical information

The differential diagnosis of abnormalities in the prostate is broad, covering common (acinar adenocarcinoma, benign prostatic hyperplasia, chronic prostatitis, hemorrhage, cysts, calcifications, atrophy and fibrosis) and less common conditions (tumors other than acinar adenocarcinoma, granulomatous prostatitis containing tuberculosis, abscesses and other conditions, and idiopathic disorders such as amyloidosis and exophytic benign prostatic hyperplasia). Recent advances in magnetic resonance imaging (MRI) of the prostate gland and imaging guidelines, such as the Prostate Imaging Reporting and Data System version 2.1 (PI-RADS v2.1), have dramatically improved the ability to distinguish common abnormalities, especially the ability to detect clinically significant prostate cancer (csPCa). Overlap can exist in the clinical history and imaging features associated with various common/uncommon prostate abnormalities, and biopsy is often required but is invasive. Prostate abnormalities can be divided into two categories: category 1, diseases for which PI-RADS scores are suitable for use, and category 2, diseases for which PI-RADS scores are unsuitable for use. Radiologists must have an intimate knowledge of other diseases, especially uncommon conditions. Past relevant history, symptoms, age, serum prostate-specific antigen (PSA) levels, MRI manifestations, and the applicability of the PI-RADS assessment should be considered when diagnosing prostate abnormalities.

Spectrum of Cystic Epithelial Tumors of the Prostate: Most Cystadenocarcinomas Are Ductal Type With Intracystic Papillary Pattern

Cystic epithelial tumors arising from the prostate are rare, and their full histologic spectrum has yet to be defined. Herein, we present 8 examples of prostatic cystic tumors including 1 giant multilocular cystadenoma and 7 cystadenocarcinomas. We divided the cystadenocarcinomas into "giant multilocular" cystadenocarcinoma (3) and "microscopic" cystadenocarcinoma (4) because of their differing clinical presentations with clinically apparent cystic masses in the former. The cystadenoma was an 11 cm multilocular cystic pelvic tumor in a 55-year-old man who presented with lower urinary tract symptoms. The cystadenoma was lined predominantly by benign acinar cells and had a distinct basal cell layer. No recurrence occurred 3 months after resection. The 3 patients with giant multilocular cystadenocarcinomas were 62 to 82 years old, had large pelvic cystic masses (up to 16 cm), and 2 presented with obstructive urinary and lower intestinal tract symptoms. One giant multilocular cystadenocarcinoma had a markedly high cystic fluid prostate-specific antigen at >80,000 ng/mL. All 3 giant multilocular cystadenocarcinomas were ductal adenocarcinoma with exuberant intracystic papillary formations. One tumor was associated with a high-grade noncystic conventional (acinar) adenocarcinoma (Gleason score 9 [ISUP grade group 5]). Follow-up on the 3 giant multilocular cystadenocarcinoma cases (7 to 21 mo) showed multiple metastases in 1 patient but was attributed to the high-grade conventional adenocarcinoma component. In addition, we described 4 examples of microscopic cystadenocarcinomas that were small (≤1 cm) solitary or multiple cystic tumors identified on pathologic examination of the prostate. In 3 of 4 microscopic cystadenocarcinomas the lining was ductal adenocarcinoma with occasional to exuberant papillae and appeared similar to the smaller cysts in the giant multilocular cystadenocarcinomas. One of the 4 microscopic cystadenocarcinomas had an acinar adenocarcinoma lining with occasional papillae and was associated with a conventional adenocarcinoma. Follow-up of the 4 patients with microscopic cystadenocarcinoma (1 to 14 mo) showed no evidence of disease. Review of literature highlighted similarities between the findings in our cases and previously published prostatic cystadenocarcinomas, including the markedly high cystic fluid prostate-specific antigen level in giant multilocular cystadenocarcinomas and the typical ductal adenocarcinoma morphology with intracystic papillary pattern. In conclusion, cystic epithelial tumors of the prostate exhibit unique clinicopathologic features. Cystadenocarcinomas, whether the clinically apparent giant multilocular form or the incidentally identified microscopic type, represent a rare underrecognized pattern of prostatic adenocarcinoma mostly within the histologic spectrum of the ductal variant.

Beyond Prostate Adenocarcinoma: Expanding the Differential Diagnosis in Prostate Pathologic Conditions

Recent advances in magnetic resonance (MR) imaging of the prostate gland have dramatically improved the ability to detect and stage adenocarcinoma of the prostate, one of the most frequently diagnosed cancers in men and one of the most frequently diagnosed pathologic conditions of the prostate gland. A wide variety of nonadenocarcinoma diseases can also be seen with MR imaging, ranging from benign to malignant diseases, as well as infectious and inflammatory manifestations. Many of these diseases have distinctive imaging features that allow differentiation from prostate acinar adenocarcinoma. Early recognition of these entities produces a more accurate differential diagnosis and may enable more expeditious clinical workup. Benign neoplasms of the prostate include plexiform neurofibroma and cystadenoma, both of which demonstrate distinctive imaging features. Stromal neoplasms of uncertain malignant potential are rare tumors of uncertain malignant potential that are often difficult to distinguish at imaging from more-malignant prostate sarcomas. Other malignant neoplasms of the prostate include urothelial carcinoma, primary prostatic carcinoid, carcinosarcoma, endometrioid or ductal adenocarcinoma, and mucinous adenocarcinoma. Prostatic infections can lead to abscesses of pyogenic, tuberculous, or fungal origins. Finally, miscellaneous idiopathic disorders of the prostate include amyloidosis, exophytic benign prostatic hyperplasia, and various congenital cysts. Considerable overlap can exist in the clinical history and imaging findings associated with these prostate pathologic conditions, and biopsy is often required for ultimate confirmation of the diagnosis. However, many diagnoses, including cystadenoma, mucinous adenocarcinoma, sarcoma, and abscesses, have distinct imaging features, which can enable the informed radiologist to identify the diagnosis and recommend appropriate clinical workup and management. (©)RSNA, 2016.