Zonal Distribution of Neuroendocrine Cells (NECS) within Prostates (PR) with Prostatic Carcinoma (PCA)
Yulan Gong, Sharon M Cavone, Fernando U Garcia. Drexel University College of Medicine, Philadelphia, PA
Background: NECs within the Pr gland have been well studied using normal Pr. However, NECs in patients with PCa have not been fully characterized. We studied the zonal distribution of NECs in Pr with carcinoma (Ca), within the Ca and in a cohort of metastatic cases. In addition, we determined if age, pre-operative PSA (pPSA) and proliferative index (PI) correlated with NECs.
Design: 42 cases treated with radical robotic prostatectomy were identified in the IRB approved database. Tissue microarrays (TMAs) were prepared using 1.5 mm needles. Two tissue cores from seminal vesicle (SV), central zone (CZ), transitional zone (TZ), peripheral zone (PZ) and the index Ca from whole mount paraffin blocks of each patient were used. These benign cores were obtained from at least two 10x fields away from Ca. The presence of NECs was identified with immunohistochemistry (IHC) for chromogranin A (CrgA), and synaptophysin (Syn). NECs were quantified per 100 epithelial cells. Co-expression of p63 with Crg A and Syn was also studied to assess stem cell phenotype. PI of Ca was studied with Ki-67 IHC and quantified with image analysis. Student t-test was used compare zonal distribution of NECs. In addition, fifteen cases with metastatic PCa were studied for CrgA and Syn IHC expression.
Results: Patient age ranged from 38 to 68 years old (<60, 28 cases and ≥60, 14 cases). PSA ranged from 0.8 to 37.9 ng/ml (<4, 6 cases, ≥4, 31 cases, and unknown 5 cases). CrgA revealed that NECs were highest in PZ (1.29 ± 1.78), followed by CZ (0.98 ± 1.24) and lowest in TZ (0.42 ± 0.67) (p<0.05 between all zones). Similar values were obtained for Syn (Data not shown). NECs were similar in all zones regardless of age or pPSA. Co-IHC showed NECs did not express stem cell marker p63 in all three zones. Interestingly, NECs were not present in SV epithelium. In PCa, NECs were present in 17.9% of primary PCa, no difference was observed in different Gleason grades (G6 0.49 ± 1.2%, G7 2.5 ± 0.8%, and G8-9 0.64 ± 1.9%). The PI of PCa with NECs was 2.6 ± 1.6%, PI of PCa without NECs was 3.5 ± 4.6% and there was no significant difference (p=0.62). Significantly higher NECs (33.3%) were present in metastatic PCa.
Conclusions: PZ of Pr with PCa had the highest NECs, followed by CZ and TZ. This is different from previous studies in which the TZ has the highest. Increasing age and pPSA did not affect zonal distribution of NECs. Primary PCa with NECs seems to have lower PI suggesting an inhibitory role of NECs. NECs did not exhibit stem cell phenotype. Metastatic PCa had higher NECs compared to primary PCa.
Category: Genitourinary (including renal tumors)
Monday, March 19, 2012 9:30 AM
Poster Session I Stowell-Orbison/Surgical Pathology/Autopsy Awards Poster Session # 166, Monday Morning