[756] Methods of Submitting Cores and Gleason Score as Contributory Factors to the Fragmentation of Prostate Core Biopsies Containing Adenocarcinoma

DF Fajardo, JI Epstein. Johns Hopkins Hospital, Baltimore

Background: Fragmentation of prostatic core biopsies containing prostatic carcinoma may complicate quantification of the number cores with cancer and/or the amount of tumor in a core.
Design: A search for prostate biopsy cases containing fragmented cores with cancer and cancer cases present only in unfragmented cores was performed on cases from the consult service of one of the authors. Cases were not consecutive cases but were enriched for fragmented cases to better evaluate causes of fragmentation. Cases of prostatic adenocarcinoma with fragmented cores containing cancer (n=463) and cases lacking fragmented cores (n=200) were evaluated in regards to number of parts per case, the number of cores per specimen, number of parts containing cancer, the number of parts fragmented, and the highest Gleason score in the fragmented and unfragmented cores.
Results: Mean number of fragmented parts was 1.3 (1-6). Mean number of parts was 7.7 (1-32). The mean number of parts per case were 8.1 and 7.5 in the unfragmented and fragmented cases respectively (p=0.1), yet there were significantly more fragmented cores in cases with >6 vs 6 parts (p<0.05). Mean number of parts with cancer was 2.4 (1-13). There was a significantly higher number of parts containing cancer in the fragmented cores compared to cases without fragmented cores (2.8 vs 1.6, p<0.0001). Mean number of cores per part was 2.5 (1-10). The cases containing fragmented cores with cancer had a higher number of cores per part (2.6 vs 2.1, p=0.004). Mean Gleason score was 6.5 (6-10). A higher mean Gleason score was associated with the cancer in the fragmented cores when compared to the unfragmented cores (6.6 vs 6.2, p< 0.0001). Multivariate analysis showed an association of fragmentation with the following variables: number of parts with cancer (odds ratio 1.7, p<0.0001); cores per part (odds ratio 1.3, p<0.0001); and Gleason score (odds ratio 1.3, p<0.04).
Conclusions: The more parts with cancer the more likely that at least one of the parts may show fragmented cancer. Higher Gleason score is also associated with fragmented cores, with for example large cribriform Gleason pattern 4 with little supporting stroma often fragmented. While these factors cannot be controlled, pathologists and urologists can limit the number of parts per specimen and the number of cores submitted per part to reduce the likelihood of fragmentation of cores containing prostatic adenocarcinoma.
Category: Genitourinary (including renal tumors)

Wednesday, March 11, 2009 9:30 AM

Poster Session V # 121, Wednesday Morning