Collecting duct carcinoma of the kidney: an immunohistochemical study of 11 cases.
BACKGROUND
Collecting duct carcinoma (CDC) is a rare but very aggressive variant of kidney carcinoma that arises from the epithelium of Bellini's ducts, in the distal portion of the nephron. In order to gain an insight into the biology of this tumor we evaluated the expression of five genes involved in the development of renal cancer (FEZ1/LZTS1, FHIT, TP53, P27kip1, and BCL2).


METHODS
We studied eleven patients who underwent radical nephrectomy for primary CDC. All patients had an adequate clinical follow-up and none of them received any systemic therapy before surgery. The expression of the five markers for tumor initiation and/or progression were assessed by immunohistochemistry and correlated to the clinicopathological parameters, and survival by univariate analysis.


RESULTS
Results showed that Fez1 protein expression was undetectable or substantially reduced in 7 of the 11 (64%) cases. Fhit protein was absent in three cases (27%). The overexpression of p53 protein was predominantly nuclear and detected in 4 of 11 cases (36%). Immunostaining for p27 was absent in 5 of 11 cases (45.5%). Five of the six remaining cases (90%) showed exclusively cytoplasmic protein expression, where, in the last case, p27 protein was detected in both nucleus and cytoplasm. Bcl2 expression with 100% of the tumor cells positive was observed in 4 of 11 (36%) cases. Statistical analysis showed a statistical trend (P = 0.06) between loss and reduction of Fez1 and presence of lymph node metastases.


CONCLUSIONS
These findings suggest that Fez1 may represent not only a molecular diagnostic marker but also a prognostic marker in CDC.
Vecchione
Andrea
A
Department of Urology, Kimmel Cancer Center, Thomas Jefferson University, 1025 Walnut Street, Philadelphia, PA, 19107, USA. a_vecchione@mail.jci.tju.edu
Galetti
Tommaso Prayer
TP
Gardiman
Marina
M
Ishii
Hideshi
H
Giarnieri
Enrico
E
Pagano
Francesco
F
Gomella
Leonard G
LG
Croce
Carlo M
CM
Baffa
Raffaele
R
D017766:Acid Anhydride Hydrolases / Q000378:metabolism; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D044584:Carcinoma, Ductal / Q000235:genetics / Q000378:metabolism* / Q000473:pathology; D018797:Cell Cycle Proteins / Q000378:metabolism; D050760:Cyclin-Dependent Kinase Inhibitor p27; D005260:Female; D006801:Humans; D007150:Immunohistochemistry / Q000379:methods; D007680:Kidney Neoplasms / Q000235:genetics / Q000378:metabolism* / Q000473:pathology; D008297:Male; D008875:Middle Aged; D009363:Neoplasm Proteins / Q000378:metabolism*; D019253:Proto-Oncogene Proteins c-bcl-2 / Q000378:metabolism; D016159:Tumor Suppressor Protein p53 / Q000235:genetics; D025521:Tumor Suppressor Proteins / Q000378:metabolism; D000099170:Bis(5'-adenosyl)triphosphatase
D017766:Acid Anhydride Hydrolases; D018797:Cell Cycle Proteins; D050760:Cyclin-Dependent Kinase Inhibitor p27; D009363:Neoplasm Proteins; D019253:Proto-Oncogene Proteins c-bcl-2; D016159:Tumor Suppressor Protein p53; D025521:Tumor Suppressor Proteins; D000099170:Bis(5'-adenosyl)triphosphatase