The Distribution of Residual Cancer in Radical Prostatectomy Specimens in Stage a Prostate Cancer

Abstract

To assess the volume and distribution of residual cancer after transurethral resection of the prostate in stage A cancer patients 42 step-sectioned radical prostatectomy specimens were examined, and the volume, location, grade and extracapsular extension of the residual tumor were recorded. A total of 13 patients had stage A1 tumors (5% or less tumor in the transurethral resection specimen and a Gleason sum of 7 or less) and 29 had stage A2 disease. Residual cancer was present in the radical prostatectomy specimen in 41 patients (98%) with a mean volume of 1.28 cc. The location of residual cancer, that is multifocal (76%), peripheral (81%) and distal to the verumontanum (66%), makes complete removal or even identification of residual tumor (restaging) by repeat transurethral resection improbable. Of the stage A1 cancer patients 4 (30%) had more than 1 cc residual tumor volume, extracapsular extension or seminal vesicle invasion. On the other hand, 14 of the stage A2 cancer patients (48%) had less than 1 cc residual tumor completely confined to the gland. Foci of residual cancer were found in the transition zone in 67% and in the peripheral zone in 90% of the patients. The grade of the residual peripheral zone cancer was significantly higher than that of the transition zone cancer in the same gland (p = 0.0004). Eight of 13 instances of extracapsular extension and all 5 of seminal vesicle invasion were directly attributable to peripheral zone cancer. These observations imply that the greatest threat to patients with stage A prostate cancer may be a separate, associated cancer in the peripheral zone rather than the primary transition zone cancer incidentally removed at transurethral resection.

Percentage of Gleason pattern 4 and 5 predicts survival after radical prostatectomy

“…Prostate cancer is a multifocal and heterogeneous disease with diverse histopathologic patterns. 13,[30][31][32] In evaluating a series of whole-mounted radical prostatectomies, Aihara et al 30 found that greater than half contained 3 different Gleason patterns. Recent studies have found that the volume of tumor present in biopsies does not correlate with the postoperative radical prostatectomy Gleason score, emphasizing the significance of small-volume, high-grade elements.…”

Maximum tumor diameter is an independent predictor of prostate-specific antigen recurrence in prostate cancer

“…Stamey et al 16 noted that tumor volume (as determined by computer planimetry), percent Gleason grade 4-5, positive lymph nodes, and intraprostatic vascular invasion were associated with progression as defined by increasing PSA level. 16 Tumor progression occurred in 14% of men with tumor volumes in the range of 0.5-2.0 cm 3 , compared to 97% of men with tumor volumes greater than 12.0 cm 3 .…”

“…Multiple histologic techniques have been utilized to assess tumor size since the gross features of prostatic carcinoma are subtle 1 and the tumors are often multifocal. [2][3][4] Maximum tumor diameter has been suggested as a fast, easy, and objective method of estimating the amount of tumor. Renshaw et al 5 demonstrated that measurements of the maximum diameter of the largest focus of tumor, the largest single tumor area, and the sum of the areas of two separate tumor foci correlated with tumor volume.…”

Fluorescence in situ hybridization analysis of matched primary tumour and lymph‐node metastasis of D1 (pT2–3pN1M0) prostate cancer

“…Several studies [6,8,12,29,30,34,35] showed that the long arm of chromosome 7 is genetically unstable in prostate cancer and associated with a poor prognosis [12]. Moreover, Greene et al [36] detected gains of the 7p region in 10% of localized cancers and in 56% of recurrent and hormone-resistant prostate tumours, using comparative genomic hybridization.…”