Pseudohyperplastic prostate carcinoma: histologic patterns and differential diagnosis.

Area of Science:

• Pathology
• Oncology
• Urology

Background:

• The histological similarity between pseudohyperplastic carcinoma and benign glandular proliferations poses diagnostic challenges.
• Previous literature highlights key features to avoid misinterpretation, particularly false-negative diagnoses.

Purpose of the Study:

• To classify newly identified histologic variants of pseudohyperplastic adenocarcinoma.
• To analyze architectural and cytologic features to aid in differential diagnosis.
• To improve the accurate identification of this malignancy.

Main Methods:

• Review of 34 cases of pseudohyperplastic adenocarcinoma from radical prostatectomies, transurethral resections, and needle biopsies.
• Analysis of architectural growth patterns and cytologic features.
• Comparison with benign mimics and other malignant neoplasms.

Main Results:

• Common growth patterns included nodular, complex, and mixed types; less frequent variants were also identified.
• Malignancy criteria included nuclear enlargement, apparent nucleoli, pink secretions, and transition to acinar carcinoma.
• Fifteen cases were misdiagnosed as benign, and 5 as other malignancies, underscoring diagnostic difficulties.

Conclusions:

• Pseudohyperplastic adenocarcinoma exhibits diverse histologic growth patterns, including previously undescribed variants.
• Accurate recognition of these patterns and specific cytologic criteria is essential to prevent underdiagnosis of malignancy.
• Awareness of potential mimics like adenosis and hyperplastic nodules is critical for correct interpretation.