Prostatic carcinoma with signet ring cells: a clinicopathologic and immunohistochemical analysis of 12 cases, with review of the literature.
Prostatic adenocarcinoma with a signet ring cell (SRC) component is a rare, incompletely characterized variant that must be distinguished from similar tumors of bladder or gastric origin. In this study, we used mucin and immunoperoxidase stains on formalin-fixed, paraffin-embedded sections from 12 prostatic adenocarcinomas with SRC components, with antibodies to prostate-specific antigen (PSA), cytokeratins, MIB-1, bcl-2, c-MET, CD44v6, and CD44v7; we performed a comparison study on six bladder and seven gastric carcinomas with SRCs. The prostatic SRC component was always associated with the usual high-grade adenocarcinoma. Both components were positive for PSA, AE1/AE3, and CAM 5.2 (12 cases of 12) and also expressed c-MET (5 cases of 9), CD44v6 (9 of 10), and CDv7 (9 of 10). Only rare cells stained for bcl-2 (3 cases of 9). The mean MIB-1 proliferation index was 8%. Intracellular mucin was identified (periodic acid-Schiff with diastase predigestion (PAS-D) in 9 cases of 10, mucicarmine in 5 of 10, alcian blue in 6 of 10). Bladder and gastric tumors were positive for PSA (3 cases of 6 and 2 of 7, respectively), using a polyclonal antibody, and for bcl-2 (5 cases of 6, 2 of 7), c-MET (6 of 6, 6 of 7), CD44v6 (5 of 6, 6 of 7), and CD44v7 (4 of 6, 4 of 7), with mean MIB-1 proliferation indices of 15 and 35%, respectively. All were negative for cytokeratin 34 beta E12. We conclude that prostatic adenocarcinomas with SRC components are typically accompanied by high-grade adenocarcinoma; are variably positive for mucin, with PAS-D being the most sensitive stain; show expression of PSA, cytokeratins, MIB-1, bcl-2, c-MET, and CD44 similar to that shown by high-grade adenocarcinoma components; have a low MIB-1 proliferation index; and are not always distinguishable from SRC components of bladder and stomach carcinomas with any of the above stains, including PSA.
Torbenson
M
M
Department of Pathology, University of Pittsburgh Medical Center, Pennsylvania, USA.
Dhir
R
R
Nangia
A
A
Becich
M J
MJ
Kapadia
S B
SB
D000368:Aged; D000369:Aged, 80 and over; D034961:Antigens, Nuclear; D015415:Biomarkers / Q000032:analysis*; D018279:Carcinoma, Signet Ring Cell / Q000737:chemistry / Q000473:pathology*; D006651:Histocytochemistry; D006801:Humans; D007124:Immunoenzyme Techniques; D007633:Keratins / Q000032:analysis; D019394:Ki-67 Antigen; D008297:Male; D008875:Middle Aged; D009687:Nuclear Proteins / Q000032:analysis; D017430:Prostate-Specific Antigen / Q000032:analysis; D011471:Prostatic Neoplasms / Q000737:chemistry / Q000473:pathology*; D012189:Retrospective Studies
D034961:Antigens, Nuclear; D015415:Biomarkers; D019394:Ki-67 Antigen; D009687:Nuclear Proteins; D007633:Keratins; D017430:Prostate-Specific Antigen