Volume 199 - Issue 9
The dilemmas of prostate cancer screening
Authors: Paul R McKenzie, Brett Delahunt and James G Kench
Med J Aust 2013; 199 (9): 582. || doi: 10.5694/mja13.10866
Published online: 4 November 2013
Published online: 4 November 2013
To the Editor: We are concerned
by conclusions drawn by Del Mar and colleagues,1 in stating that because some autopsy studies have claimed more than 50% prevalence of latent prostate cancer in men aged over 60 years, this could be considered normal, and that these latent cancers result in a high level of overdiagnosis of prostate cancer. The study cited was conducted at Wayne State University, ...
To the Editor: We are concerned by conclusions drawn by Del Mar and colleagues,1 in stating that because some autopsy studies have claimed more than 50% prevalence of latent prostate cancer in men aged over 60 years, this could be considered normal, and that these latent cancers result in a high level of overdiagnosis of prostate cancer. The study cited was conducted at Wayne State University, Detroit, in the early 1990s and indeed showed that as many as 70% of African American men in that age group showed latent prostate cancer.2 However, other articles relating to these data show that the lesions were very small, on average less than 2.3 mm, and were of a very low grade, mainly with a Gleason score of 2–5.3,4
In 2013, pathologists would regard carcinoma with a Gleason score of less than 6 as a rarity, and question the existence of neoplasia with a Gleason score of 1 + 1 = 2. This is reinforced by a study that reviewed 150 cases of low-grade carcinoma diagnosed at the Mayo Clinic between 1960 and 1970 and showed 21% of these to be misdiagnosed benign lesions.5 Reliance on studies such as that cited by Del Mar et al can greatly overestimate the risk of overdiagnosis of prostate cancer. Contemporary studies have shown a rate of about half this prevalence.6 Further, the clinical relevance of such small lesions has to be questioned as they would be unlikely to cause a detectable PSA rise or to be sampled by undirected core biopsies using current methods.
Competing interests
No relevant disclosures.
References
- Del Mar CB, Glasziou PP, Hirst GH, et al. Should we screen for prostate cancer? A re-examination of the evidence. Med J Aust 2013; 198: 525-527. 0_BABJFGFG
- Sakr WA, Grignon DJ, Haas GP, et al. Age and racial distribution of prostatic intraepithelial neoplasia. Eur Urol 1996; 30: 138-144. 0_i1142871
- Sakr WA, Haas GP, Cassin BF, et al. The frequency of carcinoma and intraepithelial neoplasia of the prostate in young male patients. J Urol 1993; 150: 379-385. 0_i1142873
- Sakr WA, Grignon DJ, Crissman JD, et al. High grade prostatic intraepithelial neoplasia (HGPIN) and prostatic adenocarcinoma between the ages of 20-69: an autopsy study of 249 cases. In Vivo 1994; 8: 439-443. 0_i1142875
- Bostwick DG, Chang L. Overdiagnosis of prostatic adenocarcinoma. Semin Urol Oncol 1999; 17: 199-205. 0_pgfId-2886705
- Yin M, Bastacky S, Chandran U, et al. Prevalence of Incidental prostate cancer in the general population: a study of healthy organ donors. J Urol 2008; 179: 892-895; discussion 895. 0_i1142879