Case 89

A 87-year-old male with history of Gleason group 3 tumor on androgen deprivation therapy. You noticed some foci in the resection:

1. What's your interpretation?

A: benign sclerosing adenosis

B: adenocarcinoma post treatment

C: clear cell variant of adenocarcinoma

D: fibroblastic cells

Answer

This is adenocarcinoma post ADT treatment.

Tumor Morphology (Acinar-type Adenocarcinoma)

• Architecture:

  • Tumor cells appear as:

    • Glands with compressed lumina

    • Single cells, cords, small clusters, chains

    • Solid sheets in some areas

• Cytological features:

  • Clear, vacuolated, or foamy cytoplasm

  • Shrunken, pyknotic nuclei

  • Inconspicuous or absent nucleoli

  • These regressive changes mimic:

    • Xanthomatous inflammation

    • Foamy gland variant adenocarcinoma

• Timing of Changes:

  • Apparent within 3 months of initiating ADT

  • Reversible: Nucleoli may reappear within 20 days of stopping therapy

Changes in Benign Prostatic Tissue

• Peripheral Zone:

  • Marked glandular atrophy

  • Prominent basal cells

  • Rupture of atrophic acini

  • Presence of orphaned corpora amylacea in stroma

• Transition Zone:

  • Basal cell hyperplasia

  • Occasional squamous metaplasia (previously more common with estrogen therapy)

Gleason grading not recommended:

• ADT reduces proliferative capacity of tumor

• Grades assigned post-ADT are not biologically relevant

• Grading may mislead clinical decisions and affect clinical trial eligibility

Treated tumors may resemble:

• Foamy gland carcinoma

• Prostatic xanthoma

• Benign glandular atrophy

References: Evans, A. Treatment effects in prostate cancer. Mod Pathol 31 (Suppl 1), 110–121 (2018). https://doi.org/10.1038/modpathol.2017.158

Case credit: UCSD Pathology

Author: Wangpan Jackson Shi, MD