## 4 Diagnosis of Indolent and Aggressive Forms of PCa before Treatment  
### Data  
Studies on the use of pretreatment data in patients with PCa are being conducted to facilitate clinical decisions regarding the type of treatment and to assess the risk of disease recurrence after treatment. According to the results of retrospective studies, preoperative overdiagnosis (when the stage of prostate cancer exposed before surgery is higher than that identified by the final histological conclusion) occurs in 30-45% of cases [21], and underdiagnosis--in 10-15% of cases [22; 23]. For this reason, patients with indolent forms of prostate cancer received over-treatment with difficulties in subsequent labor and social rehabilitation and a decrease in the quality of life in general; and in case of preoperative underestimation of the degree of aggressiveness of the tumor process, the volume of primary therapeutic measures, including surgical ones, was insufficient, with a high probability of disease recurrence. Thus, the correct preoperative staging of prostate cancer is one of the most important and urgent tasks of modern urological oncology. To this end, new machine techniques are being developed to improve the preoperative stage of prostate cancer.  
To classify patients with indolent and aggressive PCa, we used data from P.A. Hertzen Moscow Research Oncological Institute (Branch of the Federal State Budgetary Institution \"National Medical Research Radiological Centre\", Ministry of Health of the Russian Federation). The data sample was taken from the case histories of 341 patients operated on with a diagnosis of PCa: 124 patients with indolent PCa (class \(\omega_{1}\)) and 217 patients with aggressive PCa (class \(\omega_{2}\)). The form of prostate cancer was determined by postoperative data.  
The preoperative state of the patient is described by the following indicators:  
1. Histological analysis data (needle 12-gauge biopsy). Gleason Group (GrGl) for two characteristic biopsy sites on the Gleason scale [24]. The indicator takes the following values: \[\text{GrGl}=1\text{, if the score is 6 or less;}\] \[\text{GrGl}=2\text{, if the score is 7 = 3 + 4 (the order of the items is important);}\] \[\text{GrGl}=3\text{, if the score is 7 = 4 + 3 (the order of the items is important);}\] \[\text{GrGl}=4\text{, if the score is 8 or higher.}\]
2. Indicators of immunochemical analysis of blood (Beckman Coulter--Access 2 chemi-luminescent analyzer, USA; Hybritech calibration) [25]. \[\text{tPSA}\text{ is a total Prostate-Specific Antigen.}\] \[\text{fPSA}\text{ is a free PSA.}\] \[[-2]\text{proPSA is a precursor isoform of PSA.}\] \[\text{fPSA}/\text{tPSA}.\] \[\text{PHI}=\frac{[-2]\text{proPSA}}{\text{HSA}}\times\sqrt{\text{tPSA}} \text{ is the Prostate Health Index.}\]
3. Indicators of clinical group.  
\(V\) is the volume of the prostate according to ultrasound (cm\({}^{3}\)).  
Tumor process localization. The indicator takes on the following values:  
T1 = 1, T2 = 1, if the tumor process is local;  
T3 = 2, if the tumor process is locally distributed;  
T4 = 3, there were no cases of T4 in the study population.
4. Anthropometric indicators.  
Age (years).  
(BMI) = (body mass)/(height)\({}^{2}\) is a Body Mass Index (kg/m\({}^{2}\)).  
The form of the disease after surgery was determined by two postoperative indicators: clinical stage (GrT) and Gleason Group (GrGl). If, as a result of histological examination,it was found that the prevalence of the primary tumor in the prostate did not exceed T2 (the tumor process was local and there were no metastases to regional lymph nodes and distant metastases) and the Gleason Group was no more than six points, then the cancer status of the prostate was considered indolent. Otherwise, the PCa status was considered aggressive.