Definition
High grade primary prostatic adenocarcinoma involving pre-existing ducts
Diagnostic Criteria
Considered to represent high grade prostatic adenocarcinoma that has gained access to pre-existing large acini and ducts
Edges of tumor are smooth rather than raggedly infiltrating
Nearly always associated with high grade acinar carcinoma
Gleason pattern 5 present in about half
Very rare cases with no associated usual invasive carcinoma raise the possibility that in some cases this is a precursor lesion
Basal cells must be present at the periphery
Must fulfill one of the following three architectural/cytologic criteria
Solid or dense cribriform
Lumens comprise <50% of the total ductal lumen
Loose cribriform (>50% lumens) but with marked nuclear pleomorphism
Many nuclei at least 6 times larger than normal
Large cells may be peripherally located
Loose cribriform but with more than focal comedonecrosis
Differential diagnosis
High grade PIN must be excluded
Prostatic Intraductal Adenocarcinoma High Grade PIN
Cribriform pattern common
Cribriform pattern rare
Mitotic figures common
Mitotic figures rare
Basal cells if present are usually patchy
Basal cells widespread but may be fewer than normal
Solid or dense cribriform patterns are definitional
Solid and dense cribriform patterns not allowed
Marked nuclear pleomorphism (6 x normal) or comedonecrosis are definitional
Marked nuclear pleomorphism and comedonecrosis not allowed
The distinction from invasive cribriform acinar adenocarcinoma should be made
Although both are high grade carcinomas, intraductal carcinoma is more aggressive
Prostatic Intraductal Adenocarcinoma
Cribriform Acinar Adenocarcinoma
May have marked cytologic atypia (6x normal)
Nuclei atypical but not markedly enlarged
Basal cells present
Lacks basal cells
Smooth edges without infiltration
Frequently has ragged infiltration at edges
The distinction from ductal carcinoma is not as critical
Both are high grade carcinomas
Ductal carcinoma may have an intraductal component
Demonstrated by focal presence of basal cells
Prostatic Ductal Adenocarcinoma Non-ductal Intraductal Adenocarcinoma
Columnar cells with elongated nuclei
Cuboidal cells with round nuclei
Cribriform lumens frequently slit-like
Cribriform lumens usually round
Frequently has true papillae with vascular cores
Tufts but no true papillae
Usually lacks basal cells
Basal cells always present
Nuclear size 2-3 x normal
Nuclear size may be 6 x normal
Intraductal adenocarcinoma with a solid pattern may be confused with urothelial carcinoma growth into prostatic ducts
Prostatic Intraductal Adenocarcinoma
Urothelial Carcinoma Involving Prostatic Ducts
PSA and PAP positive
PSA and PAP negative
HMWCK and p63 negative
HMWCK and p63 positive
Bibliography (for general references see Prostatic Acinar Adenocarcinoma )
Humphrey, P. A. (2012), Histological variants of prostatic carcinoma and their significance. Histopathology, 60: 59–74.
Herawi M, Epstein JI. Immunohistochemical antibody cocktail staining (p63/HMWCK/AMACR) of ductal adenocarcinoma and Gleason pattern 4 cribriform and noncribriform acinar adenocarcinomas of the prostate. Am J Surg Pathol. 2007 Jun;31(6):889-94.
Morgan TM, Welty CJ, Vakar-Lopez F, Lin DW, Wright JL. Ductal adenocarcinoma of the prostate: increased mortality risk and decreased serum prostate specific antigen. J Urol. 2010 Dec;184(6):2303-7.
Robinson B, Magi-Galluzzi C, Zhou M. Intraductal carcinoma of the prostate. Arch Pathol Lab Med. 2012 Apr;136(4):418-25.
Guo CC, Epstein JI. Intraductal carcinoma of the prostate on needle biopsy: Histologic features and clinical significance. Mod Pathol. 2006 Dec;19(12):1528-35.
Robinson BD, Epstein JI. Intraductal carcinoma of the prostate without invasive carcinoma on needle biopsy: emphasis on radical prostatectomy findings. J Urol. 2010 Oct;184(4):1328-33.
Robert V Rouse MD
Original posting/updates: 6/1/12
Classification/Lists
Prostatic Carcinomas
Prostatic Benign Lesions/Patterns Simulating Carcinoma
Other Lesions
