Immunohistochemical basis for adjuvant anti-angiogenic targeted therapy for renal carcinoid: initial case report.
OBJECTIVE
To evaluate the immunohistochemical profile of a carcinoid (low grade neuroendocrine tumor of the kidney) from a patient with lymph node positive disease who remains disease free for 31 months after radical nephrectomy, lymph node dissection, and adjuvant therapy with sunitinib malate.


METHODS
Immunohistochemical staining was performed for chromogranin, synaptophysin, CD31, VEGF, HIF-1α, HIF-2, and Glut-1. Staining was evaluated in 3 high-power fields and samples scored as strongly positive (3+), moderately positive (2+), weakly positive (1+), or negative (0). A clear cell renal cell carcinoma was used as positive control.


RESULTS
Immunohistochemical staining was strongly positive VEGF, weak to moderately positive for HIF-2, and negative for HIF-1α and Glut-1.


CONCLUSIONS
Our case of primary renal carcinoid stained intensely for VEGF and HIF-2, consistent with a VHL-HIF1-HIF2-Glut1 independent pathway for VEGF activation. These data suggest that like other neuroendocrine tumors, primary renal carcinoid is a potential target for anti-angiogenic therapy with sunitinib.
Finley
David S
DS
Department of Urology, University of California Irvine Medical Center, Orange, CA 92868, USA. finds@uci.edu
Narula
Navneet
N
Valera
Vladimir A
VA
Merino
Maria J
MJ
Fruehauf
John
J
Wu
Mark Li-cheng
ML
Linehan
W Marston
WM
Clayman
Ralph V
RV
D000328:Adult; D020533:Angiogenesis Inhibitors / Q000627:therapeutic use*; D042501:Angiogenic Proteins / Q000037:antagonists & inhibitors* / Q000378:metabolism; D002276:Carcinoid Tumor / Q000188:drug therapy* / Q000378:metabolism / Q000473:pathology; D002292:Carcinoma, Renal Cell / Q000188:drug therapy* / Q000378:metabolism / Q000473:pathology; D017024:Chemotherapy, Adjuvant; D005260:Female; D006801:Humans; D007124:Immunoenzyme Techniques; D007680:Kidney Neoplasms / Q000188:drug therapy* / Q000378:metabolism / Q000473:pathology; D014057:Tomography, X-Ray Computed
D020533:Angiogenesis Inhibitors; D042501:Angiogenic Proteins