Correlation between chromosome 9p21 locus deletion and prognosis in clinically localized prostate cancer.

BACKGROUND: Some studies have reported that deletions at chromosome arm 9p occur frequently and represent a critical step in carcinogenesis of some neoplasms. Our aim was to evaluate the deletion of locus 9p21 and chromosomes 3, 7 and 17 in localized prostate cancer (PC) and correlate these alterations with prognostic factors and biochemical recurrence after surgery. METHODS: We retrospectively evaluated surgical specimens from 111 patients with localized PC who underwent radical prostatectomy. Biochemical recurrence was defined as a prostate-specific antigen (PSA) >0.2 ng/mL and the mean postoperative follow-up was 123 months. The deletions were evaluated using fluorescence in situ hybridization with centromeric and locus-specific probes in a tissue microarray containing 2 samples from each patient. We correlated the occurrence of any deletion with pathological stage, Gleason score, ISUP grade group, PSA and biochemical recurrence. RESULTS: We observed a loss of any probe in only 8 patients (7.2%). The most common deletion was the loss of locus 9p21, which occurred in 6.4% of cases. Deletions of chromosomes 3, 7 and 17 were observed in 2.3%, 1.2% and 1.8% patients, respectively. There was no correlation between chromosome loss and Gleason score, ISUP, PSA or stage. Biochemical recurrence occurred in 83% cases involving 9p21 deletions. Loss of 9p21 locus was significantly associated with time to recurrence (p = 0.038). CONCLUSIONS: We found low rates of deletion in chromosomes 3, 7 and 17 and 9p21 locus. We observed that 9p21 locus deletion was associated with worse prognosis in localized PC treated by radical prostatectomy.

Chromosome 9p deletions are an independent predictor of tumor progression following nephrectomy in patients with localized clear cell renal cell carcinoma.

OBJECTIVES: Chromosome 9p deletions have been observed in 14% to 36% of patients with clear cell renal cell carcinoma (ccRCC) and are associated with advanced-stage tumors. We evaluated whether chromosome 9p deletions are an independent predictor of worse outcomes in patients with localized ccRCC. MATERIALS AND METHODS: In this retrospective study, tumor samples from 94 patients with ccRCC NX-0 M0 who underwent radical nephrectomy or conservative renal surgery were analyzed using a fluorescence in situ hybridization technique. RESULTS: The median follow-up period was 11.7 years, and 9p deletions were identified in 15% of cases. The cancer-specific survival rate estimated at 5 and 10 years was 99% and 96%, respectively, for patients without such chromosomal losses and 71% and 57% in patients with a loss of 9p (P<0.001). Chromosome 9p deletions were an independent prognostic factor in a multivariate analysis, increasing the risk of death due to disease by 28-fold (95% CI: 5-155, P<0.001). In patients with a low risk of progression, i.e., a low Stage, Size, Grade, and Necrosis score (0-2), low risk according to the University of California at Los Angeles Integrated Staging System, and low risk according to the pathological triad used at University of Sao Paulo, tumors with 9p deletions were significantly associated with a poorer cancer-specific survival at 10 years: 70%, 67%, and 67% vs. 98%, 97%, and 98%, respectively, in patients without 9p deletions. CONCLUSION: Chromosome 9p deletions independently establish a poorer prognosis for patients with localized ccRCC, providing further relevant clinical information that may improve the predictive ability of the main prognostic systems currently in use.