Publikationsdatenbank

Mitotic count in canine cutaneous mast cell tumors:
manual counts consistent with highest mitotic density? (2019)

Art

Vortrag

Autoren

Bertram, Christof (WE 12)

Aubreville, Marc

Gurtner, Corinne

Bartel, Alexander (WE 16)

Corner, Sarah

Dettwiler, Martina

Kershaw, Olivia (WE 12)

Noland, Erica

Schmidt, Anja

Sledge, Dodd

Smedley, Rebecca

Thaiwong, Tuddow

Kiupel, Matti

Maier, Andreas

Klopfleisch, Robert (WE 12)

Kongress

ACVP & ASVCP 2019 Concurrent Annual Meeting

San Antonio, 09. – 13.11.2019

Quelle

Sprache

Englisch

Verweise

URL (Volltext): https://cdn.ymaws.com/www.acvp.org/resource/resmgr/meetings_&_events/2019/2019_acvp_and_asvcp_final_ab.pdf

Kontakt

Institut für Veterinär-Epidemiologie und Biometrie

Königsweg 67
14163 Berlin
+49 30 838 56034
epi@vetmed.fu-berlin.de

Abstract / Zusammenfassung

Sunday, November 10, 201911:30 a.m. –11:45 a.m.

Background:
Current prognostication of canine cutaneous mast cell tumors (ccMCT) requires determining the mitotic count (MC) in tumor areas with the highest mitotic density, which is assumed to correlate best with biological behavior. Due to inconsistent
area selection, we speculated that identifying highest density might be hampered by inter-observer variation.

Objective:
To compare the manual MC with the true mitotic distribution in ccMCTs.

Methods:
All mitotic figures in digital slides of 28 ccMCTs were labeled by two pathologists. Image analysis was used to determine ground truth MC distribution throughout the tumor section. Thereafter, manual MCs were performed on scanned sections by eleven pathologists.

Results:
The ground truth MC varied between different tumor areas in most examined cases. Manual MCs were within the highest ground truth quartile in only 51.9% of the cases (random chance: 25%). However, there was substantial agreement between participants (κ= 0.865) in consistently identifying either a MC≥7 or MC<7. High accuracy was due to the majority of MCTs having either overall high or low MCs. In contrast, in there were 95.5% falsely low counts in four borderline cases.

Conclusion:
Manual MCs often do not represent the most mitotically active tumor regions and area selection may have a significant impact on the MC, in particular in borderline cases. Further standardization of area selection, such as by computerized analysis, is required to achieve higher accuracy of MCs. Regardless of the high variability of mitotic density, prognostication based on manual MCs was very reproducible when published cut-off values were applied.