Chromosome 9p deletions identify an aggressive phenotype of clear cell renal cell carcinoma.
BACKGROUND
The authors investigated whether deletion of chromosome 9p in clear cell renal cell carcinoma (ccRCC) predicted worse disease-specific survival (DSS) and recurrence-free survival (RFS) and whether it was associated with more aggressive behavior in small renal masses.


METHODS
In total, 703 ccRCC tumors were analyzed using fluorescence in situ hybridization (316 tumors) and cytogenetics (388 tumors). Tumor grade, classification, and size; 9p status; Eastern Cooperative Oncology Group performance status (ECOG PS); lymph node involvement; and the presence of metastasis were recorded. Outcomes were stratified by 9p status, and a Cox proportional hazards models was constructed using TNM staging, ECOG PS, tumor size, tumor grade, and 9p status.


RESULTS
Deletions of 9p were detected in 97 tumors (13.8%). At presentation, 9p-deleted tumors were larger and were more likely to be high grade (grade 3 or 4), to have a high tumor (T) classification (T3-T4), and to have lymph node or distant metastases (P < .01). The median DSS for patients with and without 9p deletions was 37 months and 82 months, respectively (P < .01). In patients with localized disease, the median RFS in those who had 9p deletions was 53 months and was not reached in those without 9p deletions (P < .01). In patients who had localized lesions that measured ≤4 cm in greatest dimension, 9p-deleted tumors were more likely to recur (19% vs 2%; P = .01).


CONCLUSIONS
Deletion of chromosome 9p in ccRCC occurred in 14% of patients and was associated with higher grade and T classification, and the presence of lymph node and distant metastases. In addition, 9p deletion independently conferred a worse prognosis for patients with localized ccRCC, and most noteworthy, in patients with localized, small renal masses. Preoperatively identifying patients with 9p deletions will improve risk stratification and will help to select appropriate patients for surveillance protocols or aggressive treatment.
La Rochelle
Jeffrey
J
Department of Urology, David Geffen School of Medicine at the University of California, Los Angeles, Los Angeles, California 90025, USA.
Klatte
Tobias
T
Dastane
Aditi
A
Rao
Nagesh
N
Seligson
David
D
Said
Jonathan
J
Shuch
Brian
B
Zomorodian
Nazy
N
Kabbinavar
Fairooz
F
Belldegrun
Arie
A
Pantuck
Allan J
AJ
D002292:Carcinoma, Renal Cell / Q000235:genetics* / Q000401:mortality / Q000473:pathology; D002872:Chromosome Deletion; D002899:Chromosomes, Human, Pair 9; D018572:Disease-Free Survival; D006801:Humans; D007680:Kidney Neoplasms / Q000235:genetics* / Q000401:mortality / Q000473:pathology; D008207:Lymphatic Metastasis; D009362:Neoplasm Metastasis