International Journal of Clinical Case Reports 2017, Vol.7, No.8, 33-37
36
shown to have positivity in 25% cases (Iczkowski et al., 2003), which suggests that some ACC may show a
myoepithelial phenotype. CK7 positivity is restricted to the luminal cells only (Iczkowski et al., 2003).
The differential diagnosis for this rare tumor includes benign prostatic hyperplasia, poorly differentiated
adenocarcinoma and poorly differentiated squamous cell carcinoma.
(1) An elevated Ki67 labelling index (>25%) helps to differentiate benign prostatic hyperplasia from ACC.
(2) Poorly differentiated adenocarcinoma is a close differential for ACC. Morphologically, abundance of
extracellular PAS positive mucin favors ACC while acinar adenocarcinoma usually lacks a myxoid response. On
IHC, cells of acinar adenocarcinoma are positive for PSA. Immunoreactivity for CK14 and immunonegativity for
HMWCK favors adenocarcinoma while Negativity for PSA, CK14 and positivity for HMWCK favors ACC.
(3) Epithelial keratinization, intercellular bridges and lack of acinar pattern favors poorly differentiated squamous
cell carcinoma. p63 immunoreactivity also helps to distinguish poorly differentiated squamous from ACC.
There is no common consensus on the treatment for prostatic ACC. The commonly accepted effective treatment is
Radical Retropubic Prostatectomy. The efficacy of hormonal therapy in treating ACC prostate is still controversial.
But Shrawan et al (2014) reported hormonal therapy as a viable treatment option in patients with locally advanced
and metastatic disease. Due to scarcity of cases prognosis is not well defined. A 5-year metastatic potential ranges
from 5–10% in T1/T2 tumor to 50–85% in stage T3/T4 tumor (Chang et al., 2013).
3 Conclusion
Adenoid cystic/basal cell carcinoma is a relatively rare but distinctive tumor in the prostate gland. The main
differential diagnosis includes benign basal cell hyperplasia and conventional adenocarcinoma with cribriform
spaces. Correct diagnosis is important because of its potential for extra-prostatic extension. Initial suspicion of
malignancy is difficult as the serum PSA level is normal. Recognition of this rare entity is important for making
accurate histopathological diagnosis and proper treatment.
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