The treatments of localized PCa include AS, EBRT, RP and BT. RP is considered a standard treatment for early stage PCa[2]. Because of the complete resection of the tumor and detailed pathological analysis, the surgery is selected more commonly by patients. Major advantages of RP include precise assessment of the extent of the disease at a low morbidity cost, high level of confidence in the long-term eradication, ease of detection of recurrence with a tumor marker, and availability for treatment of the long-term complications (i.e. urinary incontinence and erectile dysfunction) that affect the quality of life. Unfortunately, poor erectile function outcomes and elevated incontinence rates represent major disadvantages[3].
With the development and application of a computerized treatment planning system and new radionuclide, BT for PCa has developed rapidly. BT is a technology by which a radioactive isotope is placed inside or around the tumor. The tumor receives a high dose of radiation without elevating the dose to surrounding normal tissues. Some advantages of BT include being minimally invasive and having a definite effect and fewer complications, which may contribute to its popularity in Western countries[11]. The American Brachytherapy Society consensus guidelines suggest that BT is a safe and effective treatment for patients with localized PCa[4]. Furthermore, BT is considered a great therapeutic option for aged patients and those with complicated medical diseases who may have difficulty tolerating radical surgery[6,5].
In the present study, we analyzed 415 patients with localized PCa who underwent RP (n=280) or BT (n=135). The BT group was older, had higher iPSA, and a higher proportion of high-risk patients. The results indicated that the 3-year bRFS rate was 77.3% (low risk: 90.3%, intermediate risk: 79.6%, and high risk: 71.3%) in the RP group versus 84.0% (low risk: 90.9%, intermediate risk: 93.8%, and high risk: 80.7%) in the BT group. Although the 3-year bRFS for RP was lower compared with BT, there was no statistically significant difference between the two groups (all P > 0.05). In addition, there was no significant difference between RP and BT with regard to bRFS by multivariate analysis. The 3-year CSS was 100% for the two groups with low- and intermediate-risk disease. For high-risk disease, the 3-year CSS was 92.8% in the RP group versus 92.4% in the BT group, a non-statistically significant difference (P > 0.05).
In a recent study, Giberti C et al.[12] reported similar 5-year biochemical disease-free survival rates for RP (91.0%) or BT (91.7%) in patients with low-risk PCa. Fisher CM et al.[13] reported a comparative study of men with low- to intermediate-risk PCa treated with BT and RP. After RP, the 5-year bRFS were 96.1% and 90.6% for low- and intermediate-risk patients, respectively. After BT, the 5-year bRFS were 92.5% and 95.8% for low- and intermediate-risk disease, respectively. The 5-year CSS for patients was 100% for both RP and BT. This finding argued that excellent disease control outcomes can be achieved after RP and BT for men with early stage localized PCa. Similarly, Colberg et al.[14] reported that BT provided equivalent 5-year bRFS compared with RP in patients with early PCa.
These results were similar with our study. The 3-year bRFS (93.8%) in the BT group was higher than that (79.6%) in the RP group for intermediate risk patients, but the difference between the two groups did not reach statistical significance (P=0.213). We considered that this result may be related to lower number of intermediate-risk patients in BT group.
There are a large number of prognostic factors of PCa, such as age, initial PSA, Gleason score, and T stage[15]. Ciezki et al.[16] reported that clinical stage T3, biopsy Gleason score 8-10, higher pretreatment PSA, shorter ADT duration and more frequent PSA testing following therapy were associated with significantly worse bRFS. Zhou et al.[17] reported that clinical stage ≥ T2b, was associated with significantly worse bRFS. Similarly, in the multivariate analysis of the present study, we also considered clinical stage ≥ T2b as the main independent prognostic factor for bRFS. The treatment modality, age, iPSA and Gleason score exerted no influence on bRFS.
It is necessary to consider not only cancer control but also HRQoL for patients facing the decision of which treatment to choose for localized PCa. HRQoL was measured in patients treated for localized PCa with RP and BT using the EPIC questionnaire at baseline and 3, 6, 12, and 24 months after the treatment. The EPIC is a 50-item questionnaire with eight domains, including urinary function, urinary irritation/obstruction, urinary incontinence, urinary bother, bowel function, bowel bother, sexual function and sexual bother[10]. Each domain is scored from 0 to 100, with higher scores indicating better HRQoL. For HRQoL in this study, compared with baseline, both treatments produced a significant decrease in HRQoL in different aspects at 3, 6 months and 1 year after treatment. Patients in the BT group had lower HRQoL with regard to urinary irritation/obstruction and bowel function or bother, while patients in the RP group had lower HRQoL regarding urinary incontinence and sexual function or bother. The scores reached a nadir 3 months after treatment and then recovered. There was no significant difference in HRQOL aspects between the two groups after 2 years of follow-up.
Chen RC et al.[18] reported a comparative study about the quality of life after RP, EBRT, and BT vs AS. Compared with AS, sexual dysfunction worsened by 3 months in patients who underwent RP, EBRT, and BT. Compared with AS at 3 months, worsened urinary incontinence was associated with RP, acute worsening of urinary obstruction and irritation with EBRT and BT, and worsened bowel symptoms with EBRT. By 24 months, the mean scores between the treatment groups vs AS were not significantly different in most domains. Giberti C et al.[12] reported the functional outcomes after radical retropubic prostatectomy (RRP) versus BT for the treatment of low-risk PCa during a 5-year assessment. At 6 months and 1 year, both treatments produced a significant decrease in aspects of the quality of life, while in BT patients, a significantly higher and longer lasting rate of urinary irritation disorders but better erectile function than in the RRP group. No differences in the functional outcomes were encountered after 5 years in either group.
The incidence of urinary irritation or obstruction was higher after BT, which is related to the dose and distribution of radioactive seeds[19]. Urethral irradiation dose should be reduced as much as possible in order to reduce postoperative urinary irritation or obstruction. Furthermore, Elshaikh et al.[20] found that prophylactic tamsulosin before BT significantly improved lower urinary tract symptoms. Transurethral resection of the prostate (TURP) may be considered for recurrent urinary retention due to bladder outlet obstruction. In this study, three patients eventually required TURP because of prolonged urinary retention. The urinary incontinence and sexual function in the BT group was better than that in the RP group. This is because BT preserves the prostate’s anatomical structure and does not directly damage the neurovascular bundle. Therefore, BT is a potential alternative therapeutic modality to RP for patients (especially for aged patients or those with complicated medical diseases) seeking a potentially curative treatment.