NEW ORLEANS, LA USA (UroToday.com) - In her session, Dr. Donna Hansel, a pathologist from UC San Diego discussed the challenges that pathologists experience when evaluating bladder tumors resected transurethrally. She emphasized that these specimens are some of the most difficult to assess, in part due to significant variability in the amount of tissue available for examination as well as the frequent presence of cautery artifact.
From a pathologist’s perspective more detailed reports of pathologic findings may better capture patients with higher-risk disease. She pointed out that reports of grade heterogeneity within a single tumor did not represent diagnostic ambiguity. Pathologists’ use of the descriptive term “focal high-grade disease” within a predominantly low-grade tumor indicated the presence of high-grade disease comprising less than 5% of the tumor, an arbitrary cutoff used to distinguish focal disease from upclassification.
Dr. Hansel then went on to discuss the challenges that exist in the diagnosis of variant morphologies (e.g., micropapillary). She discussed that while variant morphologies are present in up to 50% of cases, their identification is highly variable, particularly in the community. Sensitivity of transurethrally resected tumors for detecting variant morphologies is low at 39%, mostly due to under-sampling. Significant interobserver variability exists, due in part to a lack of definitive guidelines.
With regards to invasive disease, some ambiguity exists with the nomenclature for minimally invasive disease, which would benefit with standardization. An additional challenge with invasive disease is distinguishing invasion of the muscularis propria versus the muscularis mucosa which might be clouded by the presence of cautery artifact. Dr. Hansel pointed out that cautery and crush artifact may also complicate the diagnosis of angiolymphatic invasion.
She concluded by saying that the solution for these challenges requires collaboration and communication between urologists and pathologists. From the urologists’ side, increasing sampling and minimizing cautery artifact are important. From the pathologists’ perspective the use of more detail in reporting, as well as the development of new markers, may help to decrease diagnostic ambiguity.
Presented by Donna Hansel, MD, PhD at the American Urological Association (AUA) Annual Meeting - May 15 - 19, 2015 - New Orleans, LA USA
University of California, San Diego, CA USA
Reported by Timothy Ito, MD, medical writer for UroToday.com