Chapter 1 14 Besides DRE and radiological examination, histopathological verification is obtained through systematic biopsies. Currently, the European Association of Urology (EAU) guidelines recommend mp-MRI-targeted biopsies, as this improves the detection of International Society of Urological Pathology (ISUP) grade ³ 2 prostate cancer.28 Histopathology is needed for verification of the tumour type (most often adenocarcinoma) and for establishing the Gleason score.35 The Gleason score consists of two scores for the two most dominant growth patterns. This ranges from one (well differentiated) to five (poorly differentiated). The two scores result in a sum score (Table 1). In case only a single dominant growth pattern is present, this is counted twice. In the original grading system, sum scores ranged from two to ten. Currently, sum scores 2-5 are no longer assigned.36 Five grade groups, as suggested by Epstein et al.36, can be distinguished based on the sum score (Table 1). Gleason sum score Grade group £ 6 1 3 + 4 = 7 2 4 + 3 = 7 3 8 4 9 or 10 5 The combination of the clinical T-stage, Gleason grade group, and serum PSA level allows for stratification of patients into risk groups (Table 2). These prognostic groups are based on the risk of cancer recurrence after treatment. Several risk group stratification guidelines have been established, with minor differences in the definition of intermediate- and high-risk disease.28,37–39 In recent years, specific risk groups have been identified – such as favourable and unfavourable intermediate-risk – to aid treatment individualisation (Table 2).37 Treatments for primary localised prostate cancer Several curative treatment options exist for patients with localised, non-metastatic prostate cancer, depending on the risk classification. In case of active treatment, whole-gland treatment is generally offered to patients in the form of surgery (radical prostatectomy [RP]) or radiotherapy. Both treatments appear to have equivalent outcomes with respect to disease control in selected patients.40 Nevertheless, there are differences in terms of expected side effects and potential complications. In (very) low-risk patients, active surveillance is the preferred strategy, as these indolent tumours may not need active treatment right away – or ever. Long-term data in predominantly low-risk patients shows that 10-year prostate cancer-specific mortality is very low (approximately 1%) and does not differ between patients who initially undergo active treatment (RP or radiotherapy) or active surveillance (with or without active treatment at a later point in time).40 However, disease progression occurs – not unexpected – more frequently in patients who undergo Table 1 – Gleason sum scores and grade groups.
RkJQdWJsaXNoZXIy MTk4NDMw