No more lesive prostate cancer diagnosis

Andrea Fandella1, Francesco Di Toma2, Sara Benvenuto1
  • 1 Casa di Cura Giovanni XXIII - U.O. Urologia (Monastier di Treviso)
  • 2 Casa di Cura Giovanni XXIII - U.O. Radiologia (Monastier di Treviso)

Objective

In Europe, PCa is the most common solid neoplasm, with an incidence rate of 214 cases per 1000 men, outnumbering lung and colorectal cancer. Nowadays we have a problem of over diagnosis of prostate cancer (PC).
A reference strategy that screens men aged 50 to 74 years annually with a PSA threshold for biopsy referral of 4 µg/L reduces the risk for prostate cancer death to 2.15%, with risk for overdiagnosis of 3.3%.
We have the duty to identified only the significant PC. PSA is not enough sensible to rule out latent PC. Pro2PSA and PHI (prostate health index) can help us (1). Multi-parametric MRI (mp-MRI) may have a role in ruling-out clinically significant prostate cancer.
we decided to perform for patients with psa values between 4:10ng/ml to the possibility to test the PHI and in those patients in whom the PHI was lower at 40 to subject them to mpMRI.

Methods and results

Between January 2011 and December 2013 were evaluated 220 men with a mean age of 67 years (range 40-76) and psa average value of 6.2 ng / ml (range 4,1-10). After running the PHI performed MP-MRI. (T1/T2, dynamic contrast enhancement and diffusion weighting, 1.5Tesla, pelvic phased array). 2 uro-radiologists experienced MRI on prostate evaluated the images and put them in correlation with patient age and PSA.
Each prostate was divided into 4 regions of interest (ROI) and a score of 1 to 5 assigned to each ROI (1 – ‘no cancer’, 5 – ‘highly suspicious’). 95 patiens had a negative mpMRI they enter in a program of follow-up. 125 underwent trus guided biopsy for suspicious lesions.

Discussion

In 125 lesions evidenced by MRI found 75 tumors (46 Gleason 7 and 29 Gleason 6) at the first biopsy .
In 95 patients who underwent follow-up, 85 have the Psa over time remained stable and 10 instead had a significant increase in the PSA. Therefore were subjected to biopsies 8 Gleason 6 cancer were found
In this setting, low risk patients (PSA 30< 40)
For optimal clinical decision making, it is important not only to know the location of clinically significant cancer foci, but also the likelihood that such foci demonstrate an aggressive phenotype. Because higher-grade lesions tend to have higher cellular density, it follows that higher-grade lesions would demonstrate more pronounced restricted diffusion on DWI sequences. (2-4) Indeed, several publications have reported an inverse correlation between Gleason score and ADC values derived from DWI (3-4). Attempts to define ADC cutoff values to differentiate between low-grade lesions and intermediate- to high-grade lesions have been hampered by the overlap in ADC values for different aggressiveness categories described in different publications. Litjens et al (5) recently reported substantial inter-patient variation in ADC values in normal PZ tissue, and showed a significantly improved ability to discriminate between low-grade and high-grade lesions when a given patient’s background ADC values in noncancerous PZ tissue are taken into account. In the authors’ experience, DWI performs better for aggressiveness assessment than DCE-MRI. The high negative predictive value for clinically significant cancer as defined suggests that mp-MRI may have a role in ruling-out clinically significant prostate cancer. This finding could be used to address the over-diagnosis burden from PSA screening by using mp-MRI as a triage test to identify men who could avoid a prostate biopsy.

References

1.Lazzeri M, Haese A, de la Taille A, Palou Redorta J, McNicholas T, Lughezzani G, Scattoni V, Bini V, Freschi M, Sussman A, et al. Serum isoform [-2]proPSA derivatives significantly improve prediction of prostate cancer at initial biopsy in a total PSA range of 2-10 ng/ml: a multicentric European study.
Eur Urol. 2013 Jun; 63(6):986-94.
2.Woodfield C, Tung G, Grand DJ, et al. Diffusion-weighted MRI of peripheral zone prostate cancer: comparison of tumor apparent diffusion coefficient with Gleason score and percentage of tumor on core biopsy. Am J Roentgenol. 2010;194:W316-W322.
3. Verma S, Rajesh A, Morales H, et al. Assessment of aggressiveness of prostate cancer: correlation of apparent diffusion coefficient with histologic grade after radical prostatectomy. Am J Roentgenol. 2011; 196:374-81.
4. Hambrock T, Somford DM, Huisman HJ, et al. Relationship between apparent diffusion coefficients at 3.0-T MR imaging and Gleason grade in peripheral zone prostate cancer. Radiology. 2011;259:453-61.
5. Vargas HA, Akin O, Franiel T, et al. Diffusion-weighted endorectal MR imaging at 3 T for prostate cancer: tumor detection and assessment of aggressiveness. Radiology. 2011;259:775-84
6. Litjens GJS, Hambrock T, Hulsbergen-van de Kaa C, et al. Interpatient variation in normal peripheral zone apparent diffusion coefficient: effect on the prediction of prostate cancer aggressiveness. Radiology. 2012;265:260-6

Argomenti: