Fifteen year quality of life outcomes in men with localised prostate cancer: population based Australian prospective study

Dear Editor,

This paper interested me.

1. Age-matched controls were chosen from the electoral roll. "Potential controls were checked against the New South Wales Cancer Registry to exclude those with a previous diagnosis of prostate cancer." The lack of a previous diagnosis does not exclude their having had cancer at the time they were enrolled. "The absence of evidence is not the evidence of absence." My understanding is that almost all men die with prostate cancer, but few from it. How sure were the authors about its absence in the controls?

2. "Because we were unable to ascertain whether conservatively managed patients were managed through active surveillance or watchful waiting, these patients were grouped together as active surveillance/watchful waiting."
How were active surveillance or watchful waiting done? On the basis of PSA tests, PSMA scans, or by other means? The unreliability and significance of PSA levels are much debated, especially since the well-known disclaimers by Ablin[1] and Stamey[2].

3. While the controls were age-matched, were they checked for symptoms of benign prostatic hypertrophy – with symptoms similar to complications of treatment of Ca prostate?

4. Did the authors match the ethnicity of controls and subjects? Genetic variation exists in the propensity to develop prostatic cancer[3] and in germ-line mutations mediating DNA repair processes. [4]

[1] Ablin RJ New York Times, 9 March 2010
[2] Stamey TA et al DOI: 10.1097/01.ju.0000139993.51181.5d
[3] Kristal AR et al doi.org/10.1016/j.juro.2006.11.065
[4] Pritchard CC et al DOI: 10.1056/NEJMoa1603144