Valeur prédictive de l’inflammation prostatique asymptomatique dans la survenue du cancer de la prostate

Histological inflammation and risk of subsequent prostate cancer among men with initially elevated serum prostate-specific antigen (PSA) concentration in the Finnish prostate cancer screening trial

OBJECTIVE

To assess whether histological signs of inflammation are associated with an increased risk of subsequent prostate cancer (PCa) in men with elevated serum prostate-specific antigen (PSA) concentrations and benign initial biopsy.

MATERIALS AND METHODS

Study subjects were men aged 54-67 years with an elevated PSA (≥4 ng/mL or 3-4 ng/mL and free to total PSA ratio ≤0.16 or positive digital rectal examination), but a benign biopsy result within the Finnish population-based randomised screening trial for PCa, which started in 1996. A total of 293 prostate biopsies without PCa or suspicion of malignancy from the first screening round in the Tampere centre were re-evaluated by a uropathologist to assess histological inflammation. Results of the subsequent screening rounds were obtained from the trial database and PCa diagnoses made outside the screening were obtained from the Finnish Cancer Registry. The median length of follow-up was 10.5 years. Cox regression analysis was used to assess PCa risk after the initial benign biopsy.

RESULTS

Histological inflammation was found in 66% of the biopsies. Subjects with inflammation at the biopsy had a slightly lower PCa risk in the second screening round (18 vs 27%, rate ratio 0.69, 95% confidence interval [CI] 0.35-1.34) relative to men without inflammation. In further follow-up, the PCa risk remained nonsignificantly lower (hazard ratio [HR] 0.71, CI 0.46-1.10; P = 0.13). The risk was not appreciably affected by adjustment for age, PSA, prostate volume and family history of PCa (HR 0.67, CI 0.42-1.07; P = 0.092).

CONCLUSIONS

Histological inflammation in a prostate biopsy among men with an initial false-positive screening test was not associated with an increased risk of subsequent PCa, but instead with a decreased risk which was of borderline significance. Inflammation in prostate biopsy is not a useful risk indicator in PCa screening.

Does an inflammatory pattern at primary biopsy suggest a lower risk for prostate cancer at repeated saturation prostate biopsy?

INTRODUCTION

To evaluate if an inflammatory pattern at primary biopsy is associated with a lower risk for cancer in men submitted to repeated saturation prostate biopsy (SPBx).

METHODS

From January 2005 to January 2010, 320 patients, after a negative primary extended biopsy (median 18 cores), underwent SPBx by transperineal approach performing 27 cores (median). 210 (65.6%) patients had a normal parenchyma and 110 had an inflammatory pattern (34.4%) at primary biopsy (none of them complained of symptoms suggesting a diagnosis of acute prostatitis at the time of biopsy). Moreover, median prostate-specific antigen and abnormal digital rectal examination was equal to 7.3 ng/ml and 3.6% versus 8.2 ng/ml and 3.8%, respectively.

RESULTS

Prostate cancer (PCa) was found in 66 (20.5%) of 320 patients. Of these, 42 (63.6%) and 24 (36.4%; p = 0.007) had a histological diagnosis of chronic prostatitis and normal parenchyma at primary biopsy, respectively.

CONCLUSIONS

An inflammatory pattern at primary biopsy is not associated with a decrease in PCa incidence at repeated SPBx; therefore, only an accurate clinical evaluation including more parameters (i.e. urinary PCA3) could hopefully select men who need to undergo rebiopsy in the presence of persistent suspicion of cancer.

Neoplastic disorders of prostate glands in the light of synchrotron radiation and multivariate statistical analysis

The prostate gland is the most common site of neoplastic disorders in men. The pathogenesis of inflammatory cells, prostatic intraepithelial neoplasia (PIN) lesions, and prostate cancer is still under investigation. Inflammatory cells by producing free radicals are considered as major and universal contributors to cancerogenesis. PIN is regarded as a precursor lesion to prostate cancer or a marker signaling the vulnerability of the epithelium to neoplastic transformation [1]. Differentiation markers that are frequently changed in early invasive carcinoma are also changed in PIN lesions. In this study, prostate tissue samples obtained during surgical operation and classified as various disease states (inflammation, PIN lesions, and cancer) were examined. The samples were measured by means of microbeam synchrotron-radiation-induced X-ray emission (micro-SRIXE). Special attention was paid to examine the relationship between the earlier-mentioned disorders and changes in relative concentrations of S, K, Ca, Fe, Cu, and Zn. Applying the image-processing program ImageJ enabled us to select the areas of interest from two-dimensional maps of various prostate samples according to the histopathologist's evaluation. Detailed analysis of micro-SRIXE spectra based on multivariate methods shows significant differences between elemental concentrations in inflammatory cells, PIN lesions, and cancerous tissues, which confirms that this method can be used to distinguish various pathological states in prostate tissues. Information obtained in this way may provide better understanding of the biochemistry of unhealthy prostate tissues, thus opening the way to find new medicines/treatments to prevent or slow down some harmful intracellular processes.