Histologic changes in prostate carcinomas treated with leuprolide (luteinizing hormone-releasing hormone effect)....

Treatment of patients with prostate carcinoma using drugs with antiandrogenic effects is increasingly common. One of the most popular agents is leuprolide (with or without flutamide), an agonist of luteinizing hormone-releasing hormone (LH-RH). Prostates exposed to antiandrogenic agents develop distinctive pathologic changes. The ability of a group of 18 pathologists to recognize these LH-RH effects on prostate cancers and to distinguish them from poor tumor differentiation was tested using a Delphi technique.

The Delphi method maximizes the opportunity for individual contributions by eliminating opportunities for group dynamics and confrontational interaction. In this study, participants were provided with a set of duplicate transparencies and a list of written definitions of both poor tumor differentiation and LH-RH effect. They were instructed to examine the cases privately using the definitions provided and to distinguish poor tumor differentiation from LH-RH effect. Responses of the participants were shared anonymously, and each was asked to reexamine the cases in light of this knowledge.

After a learning experience accomplished by one round of examination and feedback, LH-RH effect could be correctly distinguished from poor tumor differentiation in greater than 90% of cases by 83% of the participants. A small percentage of cases confounded complete consensus, although every case was correctly identified by most participants.

The pathologic effects associated with androgen deprivation with leuprolide (plus flutamide) are sufficiently distinctive to be recognized by knowledgeable pathologists. In most cases, the tissue shrinkage representing a favorable response to the drug can be distinguished from solid or infiltrating patterns of poorly differentiated carcinoma.