Given the increasing numbers of long-term PC survivors [19], it is imperative to understand whether treatment modalities such as NSRP may result in long-lasting health benefits including better HRQoL and lower PC-specific symptom burden. This population-based study suggests, however, that HRQoL and symptom burden in PC survivors 5–10 years after diagnosis of localized PC in general does not vary according to type of surgery (NSRP versus Non-NSRP) except for the finding that PC survivors who underwent NSRP were significantly more sexually active than those treated with Non-NSRP.
In general, the results from our cross-sectional survey confirm and extend the results of the longitudinal survey based on the CaPSURE registry [14]. In addition to the results from the CaPSURE registry which described differences in SEF but comparable physical and mental health in PC survivors after NSRP and Non-NSRP, there appears to be no further differences between the two treatment groups with respect to global health status, role, emotional, cognitive and social functioning as well as burden of fatigue, insomnia, dyspnoea, constipation and pain according to our study.
Previous studies have reported that NSRP improves postoperative sexual function up to five [9,10,20] and 10 years after diagnosis [14] compared to Non-NSRP. In our study, no significant differences for SEF were reported, but patients treated with NSRP scored significantly higher on all sexual activity scales. The discrepancy between our results and the aforementioned studies are potentially based on the usage of different instruments to assess PC-specific symptom burden. In this study the EORTC-PR25 questionnaire was used whereas the other studies used the UCLA-PCI and the EPIC–26 questionnaire. In the EORTC-PR25 sexual activity is measured with two questions, which are asking about sexual interest and frequency of sexual activity. Only patients who were sexually active (183/382) answered the additional questions on the ability to have an erection and orgasm, and sexual desire [17], which correspond to the SEF domain. In contrast, all these items including level of sexual activity are part of the SEF domain in the other two instruments [21]. Therefore, results regarding SEF from studies using different QOL instruments are not directly comparable. Nevertheless, our results may have clinical implications. As most PC survivors have very good survival perspectives and are living with their partners, the finding that NSRP results in favourable sexual function even 5–10 years after diagnosis might have an impact on the treatment decision-making process.
The lack of differences with respect to long-term urinary symptoms and urinary bother might be surprising but our results are similar to another study performed in Switzerland [12], even though studies differ methodologically. The latter study continuously assessed and compared urinary incontinence over a 10 years period in PC survivors either treated with NSRP or Non-NSRP. This study was conducted in a canton, which was not part of this study, and adjusted its models for factors (such as PC volume, clinical risk group, positive margins and preoperative urinary incontinence score and PSA-values), which were not assessed in our study. Beside those differences, the similarity of the results supports the conclusion of the other study, stating that NSRP should not be conducted with the primary aim to improve urinary outcomes.
To our knowledge, this is the first study performed in Europe which compared HRQoL and PC-specific symptom burden according to NS surgery in long-term PC survivors, using a multiregional‐based design, including patient recruitment via multiple population‐based cancer registries in two different language regions. Beside these strengths, there are limitations which need to be discussed. For example, not in all study regions information were available whether participants received NSRP. Therefore, participants of two study regions were excluded from this analysis. Moreover, although we corrected our models for a range of clinical and sociodemographic variables, we did not have all information such as clinical risk group, the degree of nerve sparing, urinary outcome scores and most importantly baseline SEF, which might have influenced either the treatment choice or the outcome. Finally, information on whether RP was performed open or robotic-assisted were not assessed in the study, what might also influence the generalizability of our results, even though these two techniques yielded similar functional outcomes in short-term PC survivors as seen in randomized controlled trials [22].