Increasing Incidence of Minimal Residual Cancer In Radical Prostatectomy Specimens

Abstract

Residual cancer in radical prostatectomy specimens from men with biopsy-proven adenocarcinoma occasionally may be difficult, or even impossible, to identify. Although this finding was recently described as "minimal residual cancer" or the "vanishing cancer phenomenon," there are no data on the incidence of this phenomenon in surgical pathology practice. We evaluated 3,038 consecutive radical prostatectomies performed at the Johns Hopkins Hospital between 1988 and 1995, excluding cases with a history of transurethral resection, prior therapy with a luteinizing hormone-releasing hormone agonist, focal Gleason grade 4 or 5, capsular penetration, or a positive surgical margin. Of this group, 84 cases with minimal or no residual cancer were identified. In 60 of these cases, residual cancer was "difficult to find" (mean total volume, 0.03 cc; range, 0.01-0.08 cc); in 20 cases, residual cancers were classified as "minute" (mean total volume, 0.07 cc; range, 0.03-0.13 cc). In four cases, no residual cancer could be identified, including two cases in which the diagnosis of cancer on needle biopsy was confirmed, one case in which review of the diagnostic needle biopsy revealed only high-grade prostatic intraepithelial neoplasia, and one case in which molecular analysis demonstrated mislabeling of the needle biopsy specimen. The annual incidence of minimal residual cancer increased from 0.5% in 1988 to 4% in 1993 and has begun to plateau at 3 to 4% since 1993 (p = 0.0016 for increasing trend). These data confirm the general impression that with more vigilant screening of men for prostate cancer, there has been an associated increase in cancer with little or no residual cancer at radical prostatectomy.

‘Vanishing’ prostate cancer in radical prostatectomy specimens: incidence and long‐term follow‐up in 38 cases

“…The present incidence of no residual cancer is about two cases per 1000 RPs. This decline may be offset in recent years by two factors: (i) an increase in the number of patients receiving preoperative androgen deprivation therapy (or radiation therapy), which causes an apparent reduction in cancer volume in some patients, although this trend was not apparent in the present data because such therapy was given only rarely; and (ii) increasing vigilance in screening shows that prostate cancer is now being detected at a smaller volume and lower stage than before [1].…”

“…The incidence of 'vanishing cancer' in RP samples is uncertain, with only one study finding two cases in 3038 consecutive RPs [1]. The clinical significance of this finding is unknown and there are no previous studies.…”

“…There has also been a parallel decline in the volume of residual cancer in radical prostatectomy (RP) samples [1]. Rarely, there is little or no residual cancer despite exhaustive histological evaluation of the entire specimen [1,3].…”

Minimal or No Residual Prostatic Adenocarcinoma on Radical Prostatectomy: A 5-Year Experience With “Vanishing Carcinoma Phenomenon”

“…[9][10][11] Mazzucchelli et al, 9 in a study of 1328 RPs, found 8 cases without residual cancer on RP, for an incidence of 0.6%. Five of these cases were from hormonally treated patients and only 3 from untreated patients.…”

Vanishing endometrial carcinoma in hysterectomy specimens: probable implications for fertility sparing management

“…Both cases involved low-grade and early stage disease with low-volume tumors in the biopsy specimens. The authors proposed that the possible reasons for vanishing cancer in biopsy proven specimens as early detection of prostate cancer in asymptomatic men (2,3) and a larger number of low-stage cancers being treated by prostatectomy. In early stage and low volume tumors (<0.01 cc), determining the residual microscopic tumor in the radical prostatectomy specimen is challenging for the pathologist.…”