Multifocal, high-grade, prostatic epithelial neoplasia and prostate cancer risk
Posted Oct 18 2010 12:00am
The presence of high-grade, prostatic epithelial neoplasia (HG-PIN) in the absence of either prostate cancer or atypia (ASAP) on an initial biopsy has long been associated with risk for a subsequent diagnosis of cancer.A recent review by Dickinson discusses HG-PIN, its link to prostatic adenocarcinoma, and the significance of its presence on needle biopsy. In addition, Lee et al. have have just published a retrospective analysis of data from > 650 men to re-assess this risk.
The database analyzed by Lee et al., compiled between December 1997 and February 2008, included:
328 men diagnosed with HG-PIN alone on a first biopsy who subsequently received a second biopsy
335 men with no sign of HG-PIN (or cancer or atypia) on a first biopsy who received a second biopsy based only on clinical suspicion of risk.
All cases of HG-PIN were classified into groups based on the presence of multifocal disease (more than one biopsy core containing HG-PIN) and laterality (HG-PIN in both lobes of the prostate as opposed to just one lobe).
According to their analysis of these data, Lee et al. were able to show that:
The presence of any amount of HG-PIN alone on initial prostate biopsy nearly doubled the risk for a subsequent diagnosis of prostate cancer (hazard ratio [HR] = 1.89).
The presence of HG-PIN in more than one biopsy core (multifocal disease) more than doubled the risk for a subsequent diagnosis of prostate cancer (HR = 2.56).
The presence of HG-PIN in both lobes of the prostate (bilateral disease) also more than doubled the risk for a subsequent diagnosis of prostate cancer (HR = 2.20).
Multifocal HG-PIN on initial biopsy was associated with a 29.0 percent risk for a diagnosis of prostate cancer within 3 years.
Bilateral HG-PIN on initial biopsy was associated with a 37.0 percent risk for a diagnosis of prostate cancer within 3 years.
These data appear to substantiate data from an analogous, Canadian study by Merrimen et al. , published in August 2009, which also suggested that progression to prostate cancer was more probable in patients with multifocal HG-PIN, and that that risk rises with the number of sites of HG-PIN. Unlike Lee et al., the Canadian research team did not stratify their patients by laterality. Merrimen et al. (in another study published this year) have also shown that this risk is still evident when extended prostate biopsies are carried out compared to older sextant biopsy sampling.
It is important to remember, however, that a diagnosis of prostate cancer following an initial diagnosis of HG-PIN may still be a diagnosis of low- or very-low-risk prostate cancer. This is particularly important in men who, if diagnosed with HG-PIN in their late 60s, may be at minimal or limited risk for clinically significant prostate cancer during their lifetime. Thus, while HG-PIN is a clear risk factor for a subsequent diagnosis of prostate cancer, we are not yet aware of any analysis like this one that correlates an initial diagnosis of HG-PIN to the subsequent progression of symptomatic prostate cancer (let alone metastaic disease or prostate cancer-specific mortality).