Our results on the action of mitomycin C in the treatment of urethral stricture indicate an additional effect on the regulatory system of the cell, in particular, disruption of the arginase / NO-synthase system of blood lymphocytes, leading to an imbalance of lymphocyte regulatory systems and NO regulatory function. Decreased H 2O2-induced iNOS activity by mitomycin C suggests that these antibiotics may prevent NO overproduction in blood lymphocytes. Nitric oxide, which is produced in excess in pathological conditions of the body, has a pronounced cytotoxic effect due to the formation of peroxynitrite – a product of the interaction of NO and superoxidanion-radical, capable of destroying almost all components of the cell. It is likely that one of the mechanisms of action of mitomycin C is a decrease in hyperproduction of NO.
Development and progression of chronic kidney disease (CKD) in patients with renal cell carcinoma (RCC) after radical nephrectomy remains an extremely pressing contemporary issue. Postoperative changes of the ultrasound resistance index (RI) in the contralateral kidney not affected by the tumor after surgical treatment of RCC, as well as correlations between changes in IR and in glomerular filtration rate (GFR) remain far from being comprehensively investigated. The RI changes in the parenchyma of the intact (unaffected by the tumor) kidney before and after surgical treatment for RCC, and establishing correlations between RI changes and creatinine-dependent GFR remain unexplored issues.
In order to determine ADC, a region of interest (ROI) was established on the ADC map above the required area (prostatic neoplasm, lymph node or normal tissue) with the lowest ADC value identified as the zone with the largest hypo-intensity of MR signal. Taking into consideration that DWIs are morpho-functional images with limited morphological information, in order to improve the accuracy of anatomical comparisons of suspicious areas, we additionally performed mutual overlap of axial T2-WIs and DWIs using RadiAnt DICOM Viewer 2020.2.3 software package, obtaining a color map, where color intensities corresponded to the degrees of diffusion restriction, allowing for accurate spotting of the abnormal lesions detected on DWIs. To obtain the precise ROI position above the area of the lymph node analyzed on ADC maps, we copied the ROI from the respective slice of axial T1-WIs or T2-WIs, which have served as a precise anatomical landmark. In addition to that, to ensure more precise identification of lymph nodes, we proposed a DWIbased method of pelvic lymph node mapping using a maximum intensity projection algorithm, which facilitated spatial identification of lymph nodes and preoperative preparation (Fig. 1). No significant differences were observed when comparing mean sizes of N+ and N– pelvic lymph nodes (p > 0.05). At the same time, when comparing mean ADC values for N+ and N– pelvic lymph nodes, we did observe a tatistically significant difference: in metastatic lymph node involvement, this value was 0.74 ± 0.09 × 10-3 mm2/s, while in lymph nodes without metastatic involvement this value was 1.05 ± 0.23 • 10-3 mm2/s (p < 0.001). Such findings reflect diffusion restriction of hydrogen molecules in N+ lymph nodes due to the increased cellular density in their tissues, which is the case in the development of malignant tumors (Fig. 2). The ROC-analysis using the ADC of DWI MRI for differentiation of N+ and N– pelvic lymph nodes in PCa has shown that in a threshold cut-off value of 0.87 •
10-3 mm2/s, the sensitivity and specificity were 87% and 75%, respectively, with a high accuracy of the method, area under the curve = 0.933; 95% confidence interval (CI) = 0.852–1.0; p < 0.001 (Fig. 3)
It can be argued that the apparent diffusion coefficient of diffusion-weighted images of MRI can be used as potential imaging marker for the iagnosis of local recurrence of RCC, provided it is localized in the renal parenchyma. However, further investigations with more cases are required.
To summarize, being an attractive research topic, the radiogenomics of PCa currently is not a comprehensively investigated area of oncourology. According to preliminary research findings conducted in this field, the combination of genomics and radiomics (and presumably metabolomics, proteomics, and transcriptomics) as integrative parts of precision medicine in the future has the potential to become the foundation for a personalized approach to the management of PCa. However, there are a number of hindrances to achieving this goal, such as relatively small numbers of patients included in current studies, a lack of available large randomized controlled trials, the need to use complex integrated methods of big data analysis, the comparatively high cost of genomic profiling and imaging methods, and the question of whether, before we include any potential genomic or transcriptomic marker into radiogenomic analysis, it should first be validated in order to prove its separate clinical value. If so, it greatly and significantly shifts the horizon of the actual use of radiogenomics in clinical practice, owing to the need for a huge body of future research.