Tips for how to diagnose prostate cancer on needle biopsies
1. Look for architectural atypia. Do the glands contrast against adjacent benign glands? Do they infiltrate between benign glands? In some obvious cases this is enough for a diagnosis of cancer.
2. If 1 is not enough, go to higher magnification: Is there nuclear atypia? This may only be seen in some glands!
3. If 1+2 is not enough, use immunohistochemistry (IHC). Do not overinterpret IHC. It should mainly be used to confirm a morphological suspicion of cancer.
4. Can we rule out other lesions: benign proliferations, outpouchings of HGPIN?
5. Do I feel certain of the diagnosis? If not, call suspicious.