Macroscopic features of prostate cancer

Area of Science:

• Uropathology
• Surgical Pathology
• Oncology

Background:

• Macroscopic assessment of prostate cancer in unfixed specimens is crucial for surgical planning and diagnosis.
• Accurate gross evaluation aids in understanding tumor extent and guiding subsequent microscopic analysis.

Purpose of the Study:

• To investigate the macroscopic features of prostate cancers in unfixed prostatic tissue.
• To correlate gross findings with histological confirmation of substantial prostate cancers (≥2 mm).
• To assess the accuracy of gross tumor diameter estimation compared to microscopic extent.

Main Methods:

• Examination of 514 radical prostatectomy specimens at Karolinska University Hospital.
• Macroscopic evaluation of bisected, unfixed prostatic tissue for cancer-related features.
• Histological examination of suspicious areas to identify and quantify substantial cancers.
• Analysis of tumor characteristics including color, circumscription, and location (transition vs. peripheral zone).

Main Results:

• Macroscopic features conclusive or suspicious for cancer were observed in 52% and 24% of specimens, respectively.
• Substantial cancers (≥2 mm) were found in 94% and 69% of these areas, respectively.
• Histologically confirmed substantial cancers were identified in 56% of cases with no gross cancer findings.
• Gross tumor diameter often underestimated the microscopic tumor extent (p < 0.001).
• Transition zone tumors were more frequently orange and less frequently visualized macroscopically than peripheral zone tumors.

Conclusions:

• Macroscopic findings conclusive for cancer generally predict microscopic cancer, but substantial cancers can exist without gross evidence.
• Gross assessment of prostate cancer underestimates microscopic tumor extent.
• Transition zone tumors present greater challenges for macroscopic visualization compared to peripheral zone tumors.