It has been documented that prostate cancer is the world's leading cause of cancer and also the second commonest cancer in men which does tend to pose challenges in its diagnosis. It has been iterated that immunohistochemistry studies utilising tumour markers like high molecular weight cytokeratin, p63 aid in the diagnosis of prostate cancer. It has been known for some time that the absence of immunohistochemistry staining of prostate lesion for p63 and high molecular weight cytokeratin and presence of p504s in the biopsies indicate malignant lesions. Nevertheless, it had also been pointed out as well as documented that some rare cases of adenocarcinoma of prostate variants do demonstrate evidence of the tumour cells exhibiting p63 immunohistochemistry staining and this does pose a diagnostic dilemma that may make the unfamiliar pathologist mis-diagnose such a malignant tumour as a benign prostate lesion. p63-positive adenocarcinoma of the prostate gland is a major diagnostic pitfall. There is a danger of interpreting malignant glands as benign and arriving at a false-negative diagnosis. This can be prevented by the understanding of the pattern of immunohistochemistry staining expression related to this variant of prostate cancer. The major points that favour the diagnosis of carcinoma in these cases include: non-basal p63 staining and negative HWMCK and positive p504s staining. The biological behaviour of this particular rare variant of prostatic carcinoma is not certain and requires to be studied further into more detail. Considering the rarity of p63 expressing prostate cancers and the fact that most clinicians including pathologists, urologists, and oncologists would not have encountered a case of p63 expressing prostate cancer before in order to update all clinicians regarding this rare tumour, the ensuing article has been extensively written and divided into two parts: (A) Overview which has discussed general overview aspects of p63 expressing neoplasms and (B) Miscellaneous Narrations and Discussions from Some Case Reports, Case Series, and Studies Related to Primary p63 Expressing Adenocarcinomas of the Prostate Gland. A high-index of suspicion as well as knowledge of the histopathology examination features as well as immunohistochemistry examination features of this rare tumour is required from all clinicians. Knowledge of the treatment options, biological behaviour as well as outcome following treatment of the tumour has been extensively discussed as updating information. The update has clearly pointed out that further studies are required to determine the role of p63 overexpression in prognostication.
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