Table 1: Immunohistochemical findings of small cell carcinoma of the prostate compared with conventional high-grade adenocarcinomas [6, 8, 10, 17, 20, 3035].

AntibodySmall cell carcinomaPoorly differentiated
(approximateadenocarcinoma
percentage of(approximate percentage
positivity)of positivity)

Cytokeratin(94%)+ (70%)
Cytokeratin high(35%) −/+− (0-33%)
molecular weight
CAM 5.2(72%)+ (90%)
CK 7(39%) −/+−/+ (30%)
CK 20(11%) −/+−/+ (10%)
PSA(24%) −/+++ (85%)
PSMA(20%) −/+++ (90%)
PSAP(22%) −/+++ (95%)
P501s(25%) −/+++ (90%)
p63(40%) −/+−−/+ (15%)
TTF1(83%) +/−− (10%)
CD 56(92%) +− (10%)
Chromogranin(80%) +− (10%)
Synaptophysin(85%) +−/+ (13%)
CD44(60-96%) ++− (5%)