Radical Prostatectomy Initial procedure

• orientate the specimen using the seminal vesicles (situated on the posterior aspect) and by placing a probe (sometimes a catheter is in situ) into the prostatic urethra. This will allow identification of the flat base superiorly (proximal, bladder, base margin) and the more conical apex anteroinferiorly (distal, urethral, apical margin).

• weigh the entire specimen, measure the prostate in three dimensions (mm) and give the lengths (cm) of the attached seminal vesicles and vasa deferentia.

• paint the right, left, anterior, posterior, superior and inferior surfaces of the prostate using six different-coloured inks, including the soft tissue around the base of the seminal vesicles but not the seminal vesicles themselves. Make a note of any areas where the prostatic tissue has been disrupted by the surgical knife, as this may lead to a false positive surgical margin.

• fix the specimen by immersion in 10% formalin for at least 24-36 hours .

• dissect off the seminal vesicles and vasa deferentia and serially section these.

• the proximal and distal margins are then removed. One option is to perform a very thin (1 mm) shave and submit these intact, ensuring they are embedded such that the true margin is sectioned. Note that in respect of the distal margin, one is interested in the prostatic tissue surrounding the distal urethral limit, rather than the urethra itself, which often seems to retract into the fixed specimen.

An alternative method involves amputating the proximal and distal 5 mm of the prostate (corresponding to the bladder and urethral margins respectively) and serially sectioning these at 3 mm intervals perpendicular to the amputating cut (i.e., parallel to the urethra - Figure 30.2). This technique allows a more accurate assessment of how close the tumour extends to these margins but, as only one section is examined for each 3 mm slice, the entire margin will not have been sampled.

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1. Proximal (base) and distal (apex) margins

2. Base of seminal vesicles and vas limits

3. Prostate serial sections

4. Slices are bisected/quadranted to fit cassettes (or whole mounted)

Figure 30.2. Blocking a radical prostatectomy specimen.

• after removal of the margins, the prostate is serially sectioned at 3-4 mm intervals in the coronal plane from anterior to posterior. Some pathologists prefer to section the prostate in a horizontal plane. The slices are laid out sequentially and carefully examined, maintaining orientation with the help of the coloured inks. Malignancy is often not obvious macroscop-ically, but may appear as multifocal, peripheral, usually posterior, solid, grey-to-yellow nodules, contrasting with the central, spongy, non-neoplastic tissue. Asymmetry between lobes may be another clue.

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