ductal adenocarcinoma of the prostate was first reported by melicow and pachter   in 1967 as an endometrial carcinoma prostatic utricle . since then
, ductal adenocarcinoma of the prostate has been found to account for 0.27.5% of all prostate carcinomas .
a 73-year - old man was referred to our hospital due to an elevated prostate - specific antigen ( psa ) level of 23.4 ng / ml . he had no remarkable medical history .
the hematological and biochemical data showed no abnormal findings aside from the elevated psa levels . in february 2016 , a prostate needle biopsy detected gleason score 4 + 4 adenocarcinoma in his left prostate . computed tomography ( ct ) and
magnetic resonance imaging ( mri ) showed a higher density on his left peripheral zone ( fig 1a , b ) . in may 2016 , radical prostatectomy with lymph node resection
histologically , there were many large , clear - edged cells and cancer cells with low differentiation forming a circular shape .
based on these findings , ductal adenocarcinoma and gleason score 4 + 4 = 8 acinar adenocarcinoma with positive surgical margin were diagnosed .
the patient has not experienced recurrence or biochemical recurrence in the 10 months since radical prostatectomy .
histologically , there were many large , clear - edged cells and cancer cells with low differentiation forming a circular shape .
based on these findings , ductal adenocarcinoma and gleason score 4 + 4 = 8 acinar adenocarcinoma with positive surgical margin were diagnosed .
no adverse perioperative events were observed . the patient has not experienced recurrence or biochemical recurrence in the 10 months since radical prostatectomy .
ductal adenocarcinoma of the prostate was first reported as endometrial carcinoma of the prostatic utricle in 1967 .
recent studies have suggested that ductal adenocarcinoma of the prostate developed from the ductal epithelium , based on findings from immunohistochemical and electron microscope analyses .
histologically , ductal adenocarcinoma of the prostate is characterized by high cylindrical epithelium collate papillary or etat cribriform .
the histological differences between ductal adenocarcinoma and acinar adenocarcinoma are thought to be clear . in this case , although the prostate needle biopsy showed acinar adenocarcinoma , the surgical specimens showed ductal adenocarcinoma .
the first is a mixed type with acinar adenocarcinoma and accounts for < 75% of ductal prostate specimens .
mixed - type ductal prostate adenocarcinomas account for 5.06.6% of all prostate cancer cases , and pure - type ductal prostate adenocarcinomas account for 0.40.8% of all prostate cancer cases .
because ductal carcinomas account for 90% of all prostatic carcinoma cases , our case was assumed to be pure type . because of its extension toward the urethra , the tumor was not palpable on a digital rectal examination and showed a low psa level .
ductal adenocarcinoma of the prostate usually extends toward the urethra and shows macrohematuria and urinary symptoms at an early stage .
reported that ductal adenocarcinoma of the prostate showed a significantly poorer prognosis than acinar prostate adenocarcinoma in nonmetastatic cases .
however , in metastatic cases , there were no prognostic differences between these 2 groups .
other reports have found no marked differences in the 5-year survival rate between ductal adenocarcinoma and gleason score 810 acinar adenocarcinoma .
reported therapies of ductal adenocarcinoma of the prostate are also the same as for acinar adenocarcinoma , including radical prostatectomy , androgen deprivation therapy , and radiation therapy or a combination of these therapies .
reported that pure ductal adenocarcinoma tended to extend into the submucosal urethra ; as such , pure ductal adenocarcinoma carries a higher risk of a positive surgical margin in the urethra .
although we are not performing adjuvant therapy in this patient at present , careful observation including ct , mri , or positron emission tomography - ct should be performed , as psa does not always accurately represent cancer progression .
 ductal adenocarcinoma is an unusual variant of adenocarcinoma of the prostate . 
 a 73-year - old male was referred to our hospital for the further examination of an elevated prostate - specific antigen level of 23.4 ng / ml . 
 radical prostatectomy ( rp ) was performed based on the diagnosis obtained by a prostate needle biopsy . 
 the rp specimen revealed ductal adenocarcinoma of the prostate with positive capsular penetration . 
 we herein report a rare case of ductal adenocarcinoma of the prostate . 
Introduction
Case Presentation
Operative Procedure and Pathological Findings
Postoperative Course
Discussion
Statement of Ethics
Disclosure Statement