Outcomes of treatment for localized prostate cancer in a single institution: comparison of radical prostatectomy and radiation therapy by propensity score matching analysis.

OBJECTIVES: To compare the outcomes of radical prostatectomy (RP), intensity-modulated radiation therapy (IMRT), and low-dose-rate brachytherapy (BT) using propensity score matching analysis in patients with clinically localized prostate cancer. METHODS: A group of 2273 patients with clinically localized prostate cancer between January 2004 and December 2015 at the Yokohama City University hospital were identified. The records of 1817 of these patients, who were followed up for a minimum of 2 years, were reviewed; 462 were treated with RP, 319 with IMRT, and 1036 with BT. The patients were categorized according to the National Comprehensive Cancer Network risk classification criteria, and biochemical outcomes and overall survival rates were examined. Biochemical failure for RP was defined as prostate-specific antigen (PSA) levels > 0.2 ng/ml, and for IMRT and BT as nadir PSA level + 2 ng/ml. Propensity scores were calculated using multivariable logistic regression based on covariates, including the patient's age, preoperative PSA, Gleason score, number of positive cores, and clinical T stage. RESULTS: Median follow-up was 77 months for the RP, 54 months for IMRT, and 66 months for BT patients. After the propensity scores were adjusted, a total of 372 (186 each) and 598 (299 each) patients were categorized into RP vs IMRT and RP vs BT groups, respectively. Kaplan-Meier analysis did not show any statistically significant differences in terms of overall survival rate between these groups (RP vs IMRT: p = 0.220; RP vs BT: p = 0.429). IMRT was associated with improved biochemical failure-free survival compared to RP in all risk groups (high-risk: p < 0.001; intermediate-risk: p = 0.009; low-risk: p = 0.001), whereas significant differences were observed only in the intermediate-risk group (p = 0.003) within the RP vs BT group. CONCLUSION: The results of our propensity score analysis of mid-term localized prostate cancer treatment outcomes demonstrated no significant differences in the overall survival rate. Despite the difference in biochemical failure definition between surgery and radiotherapeutic approaches, the results of this study demonstrate improved biochemical control favoring IMRT and BT as compared to RP.

[A case of ductal carcinoma of the prostate after transurethral resection of prostate].

A 66-year-old man visited our hospital complaining of a high prostate-specific antigen (PSA) (6.9 ng/ml) and dysuria. Prostatic needle biopsies revealed no malignancy in January 1998 and February 1999 (PSA 8.0 ng/ml). Transurethral resection of prostate (TURP) was performed in March 1999. Although none of the TURP specimen showed any malignancy, the PSA level remained high (3.7 ng/ml 1 year after the TURP), and gradually increased. About 3 years later, re-biopsy was done (PSA 13.2 ng/ml) and pathological finding was moderately differentiated adenocarcinoma (Gleason score 3 + 3 = 6). After 9-month MAB, radical prostatectomy (RP) was performed in January 2003 (PSA 4.2 ng/ml). Though the RP specimen showed moderately differentiated adenocarcinoma with negative capsule penetration and negative surgical margins, PSA decreased to 2.5 ng/ml and gradually increased. Computed tomography (CT), magnetic resonance imaging (MRI), and bone scintigraphy showed neither distant metastasis nor local recurrence. Review of the RP specimen revealed ductal carcinoma with positive capsular penetration and suspicion of positive surgical margins. Although the patient was treated with maximum androgen blockade, diethylstilbestrol diphosphate, and tegafururacil, PSA gradually increased and was kept at a high level (5-6 ng/ml). In December 2005, the patient complained of anal pain and MRI showed a 4.8 x 2.3 cm tumor in the prostatic bed. Needle biopsy of the tumor revealed ductal carcinoma (PSA 6.39 ng/ml). In January 2006 (PSA 11.9 ng/ml), we initiated a treatment with 66 Gy of intensity modulated radiation therapy. In November 2006, PSA decreased to 0.279 ng/ml, and the tumor reduced (3.8 x 1.0 cm) on MRI.

[Prostate cancer development after transurethral resection of the prostate--histopathological studies of radical prostatectomy specimens].

PURPOSE: We investigated prostate cancer (ca.) development after transurethral resection of the prostate (TURP). PATIENTS AND METHODS: From 1995 to 2003, 430 patients (pts.) received TURP at Toshiba Rinkan Hospital. Of them, 23 pts. (5.3%) had incidental carcinoma (Stage A), which developed into clinically significant ca. after 1 to 5 years in 5 (22% of Stage A, 1.2% of TURP). In 13 (3.2%) of 407 Non-Stage A pts. (who had no ca. initially), prostate ca. developed after 1 to 7 yrs. A total of 21 pts. (including 3 Stage A pts. diagnosed before 1994) underwent radical prostatectomy. Stage A pts. received regular needle biopsy of prostate (Pbx). Non-Stage A pts. were followed by yearly PSA measurement and digital rectal examination (DRE). Detailed histopathological studies were done on 21 radical prostatectomy specimens. RESULTS: Clinically significant ca. developed in 8 Stage A pts. (all A2) after 1 to 14 yrs. Long term (5 or 10 years) MAB therapy changed moderately-differentiated adenocarcinoma (AC) to poorly-differentiated AC in 2 pts. during follow-up. When ca. developed PSA increased in only 3 of them, DRE was positive just in 1 pt. Tumor invasion was observed mainly in transition zone (TZ), especially anterior to urethra. In spite of no capsular penetration, surgical margin was positive in 2 pts. PSA failure occurred in another 2 pts. Thirteen Non-Stage A pts. showed aggressive ca. (6 moderately-differentiated AC, 6 poorly-differentiated AC, and 1 ductal carcinoma which showed metastasis later), most of which invaded widely in peripheral zone (PZ). Pbx before TURP was done to reveal that there was no cancer in 11 pts. Capsular penetration was seen in 4 pts. Surgical margin was positive in 4 pts. PSA (8.6 +/- 4.0 ng/ml) decreased after TURP but was kept in high level (4.8 +/- 2.2 ng/ml) after 1 year and increased (8.7 +/- 4.5) when cancer was diagnosed in all 13 pts. DRE was positive in 38% of them. Interval between TURP and diagnosis was short in pts. who had cancer of high Gleason Score (GS) or large prostate. CONCLUSIONS: As significant cancer developed in 22% of Stage A pts. (1.2% of TURP) in long term follow-up, regular Pbx (to get TZ tissue) is mandatory regardless of PSA value or DRE. Aggressive cancer developed in 3.2% of Non-Stage A pts. (3.0% of TURP). Pts. with high PSA or abnormal DRE after TURP must receive needle biopsy actively. Considering that more than 4% of TURP pts. eventually require radical prostatectomy, relatively younger pts. who received TURP have to be carefully followed for a long period.