Proposed prognostic scoring system evaluating risk factors for biochemical recurrence of prostate cancer after salvage radiation therapy

Prostate Cancer Scoring Index for Risk of Progression of Radioresistant Disease

Prostate cancer (Pca) is among the most common malignant diseases in men and the fourth leading cause of death worldwide. Surgery and radical radiotherapy (RT) remain the gold standard for the treatment of localized or locally advanced prostate cancer. The efficiency of radiotherapy treatment is limited by toxic side effects due to dose escalation. Cancer cells often develop radio-resistant mechanisms that are related to the DNA repair, inhibition of apoptosis or changes in cell cycle. Based on our earlier research on biomarkers that are involved in those cellular mechanisms (p53, bcl-2, NF-kb, Cripto-1 and Ki67 proliferation) and correlation with clinico-pathological parameters (age, PSA value, Gleason score, grade group, prognostic group), we created the numerical index for risk of tumor progression in patients with radioresistant tumors. For each of these parameters, the strength of association with disease progression was statistically assessed, and a specific number of points was assigned proportional to the strength of the correlation. Statistical analysis identified an optimal cut-off score of 22 or more as an indicator of significant risk for progression with a sensitivity of 91.7% and a specificity of 66.7%. The scoring system in the retrospective receiver operating characteristic analysis showed AUC of 0.82. The potential value of this scoring is the possibility of identifying patients with clinically significant radioresistant Pca.

GATA2 expression and biochemical recurrence following salvage radiation therapy for relapsing prostate cancer

OBJECTIVE

High GATA2 expression has been associated with an increased risk of poor clinical outcomes after radical prostatectomy; however, this has not been studied in relation to risk of biochemical recurrence (BCR) after salvage radiation therapy (SRT) for recurrent prostate cancer after radical prostatectomy. Our aim was to evaluate the association between protein expression levels of GATA2 in primary prostate cancer tumour samples and the risk of BCR after SRT.

METHODS

109 males who were treated with SRT were included. The percentage of cells with nuclear staining and GATA2 staining intensity were both measured. These two measures were multiplied together to obtain a GATA2 H-score (range 0-12) which was our primary GATA2 staining measure.

RESULTS

In unadjusted analysis, the risk of BCR was higher for patients with a GATA2 H-score >4 (hazard ratio = 2.04, p = 0.033). In multivariable analysis adjusting for SRT dose, pre-SRT PSA, pathological tumour stage and Gleason score, this association weakened substantially (hazard ratio = 1.45, p = 0.31). This lack of an independent association with BCR appears to be the result of correlations between GATA2 H-score >4 and higher pre-SRT PSA (p = 0.021), higher Gleason score (p = 0.044) and more severe pathological tumour stage (p = 0.068).

CONCLUSION

Higher levels of GATA2 expression appear to be a marker of prostate cancer severity; however, these do not provide independent prognostic information regarding BCR beyond that of validated clinicopathological risk factors. Advances in knowledge: A higher GATA2 expression level appears to be correlated with known measures of prostate cancer severity and therefore is likely not an independent marker of outcome after SRT.

An Examination of the Association between FOXA1 Staining Level and Biochemical Recurrence following Salvage Radiation Therapy for Recurrent Prostate Cancer

BACKGROUND

Standardly collected clinical and pathological patient information has demonstrated only moderate ability to predict risk of biochemical recurrence (BCR) of prostate cancer in men undergoing salvage radiation therapy (SRT) for a rising PSA after radical prostatectomy (RP). Although elevated FOXA1 staining has been associated with poor patient outcomes following RP, it has not been studied in the specific setting of SRT after RP. The aim of this study was to evaluate the association between FOXA1 staining level and BCR after SRT for recurrent prostate cancer.

METHODS

A total of 141 men who underwent SRT at our institution were included. FOXA1 staining levels in primary tumor samples were detected using immunohistochemistry. FOXA1 staining percentage and intensity were measured and multiplied together to obtain a FOXA1 H-score (range 0-12) which was our primary staining measure. P-values ≤ 0.0056 were considered as statistically significant after applying a Bonferroni correction for multiple comparisons.

RESULTS

There was not a significant association between FOXA1 H-score and risk of BCR when considering H-score as an ordinal variable or as a categorical variable (all P ≥ 0.090). Similarly, no significant associations with BCR were observed for FOXA1 staining percentage or staining intensity (all P ≥ 0.14).

CONCLUSIONS

FOXA1 staining level does not appear to have a major impact on risk of BCR after SRT.