Miroslav Louda

Magnetic Resonance Imaging in Postprostatectomy Radiotherapy Planning

PURPOSE To investigate whether the use of magnetic resonance imaging (MRI) in prostate bed treatment planning could influence definition of the clinical target volume (CTV) and organs at risk. METHODS AND MATERIALS A total of 21 consecutive patients referred for prostate bed radiotherapy were included in the present retrospective study. The CTV was delineated according to the European Organization for Research and Treatment of Cancer recommendations on computed tomography (CT) and T(1)-weighted (T(1)w) and T(2)-weighted (T(2)w) MRI. The CTV magnitude, agreement, and spatial differences were evaluated on the planning CT scan after registration with the MRI scans. RESULTS The CTV was significantly reduced on the T(1)w and T(2)w MRI scans (13% and 9%, respectively) compared with the CT scans. The urinary bladder was drawn smaller on the CT scans and the rectum was smaller on the MRI scans. On T(1)w MRI, the rectum and urinary bladder were delineated larger than on T(2)w MRI. Minimal agreement was observed between the CT and T(2)w images. The main spatial differences were measured in the superior and superolateral directions in which the CTV on the MRI scans was 1.8-2.9 mm smaller. In the posterior and inferior border, no difference was seen between the CT and T(1)w MRI scans. On the T(2)w MRI scans, the CTV was larger in these directions (by 1.3 and 1.7 mm, respectively). CONCLUSIONS The use of MRI in postprostatectomy radiotherapy planning resulted in a reduction of the CTV. The main differences were found in the superior part of the prostate bed. We believe T(2)w MRI enables more precise definition of prostate bed CTV than conventional planning CT.

Bi-weekly epirubicin, etoposide and low-dose dexamethasone for hormone-refractory prostate cancer

Background: Recent studies have demonstrated the efficacy and favorable toxicity profile of chemotherapy regimens given at lower doses and frequent intervals. The aim of our study was to evaluate the efficacy and toxicity of a bi‐weekly chemohormonal regimen consisting of epirubicin, etoposide, and low‐dose dexamethasone (EED) in patients with hormone‐refractory prostate cancer (HRPC).

Radical prostatectomy in high-grade prostate cancer, salvage and adjuvant radiotherapy.

Introduction: Prostate cancer with a Gleason score (GS) of 8–10 is linked to a higher risk of recurrence and progression. The aim of this paper is to evaluate treatment results of our high-risk patient cohort.Patients and Methods: The cohort of 42 patients with radical prostatectomy (RP) specimen histology GS 8–10 was assessed. The patients were followed up after RP and radiotherapy (RT) was delivered in case of a biochemical relapse. Adjuvant radiotherapy (aRT) was delivered only in case of a positive surgical margin (PSM). The following parameters were evaluated: biochemical progression-free survival (BPFS), overall survival (OS) and cancer-specific survival (CSS). The second objective was to evaluate adverse effects of RP and RT. Results: The median follow-up time was 88 months (18–168). RP led to BPFS in 16 patients (38%). Five patients with PSM underwent aRT and 20 underwent salvage radiotherapy (sRT). One patient died of myocardial infarction and 1 patient died of metastatic disease. Skeletal metastases were recorded in 2 patients. The BPFS in RP combinations with sRT or aRT was reached in 29 patients (69%). The OS and CSS in our cohort reached 95 and 98%, respectively. Conclusion: Management with aRT only in PSM was very effective, according to our retrospective study.

Selective aortic arch perfusion enables to avoid deep hypothermic circulatory arrest for extirpation of renal cell carcinoma with tumour thrombus extension into the right atrium

OBJECTIVES Renal cell carcinoma with a tumour thrombus extending into the right heart chambers necessitates extensive combined urological and cardiac surgery. Maximum safety and exactness in extirpation of the caval and intracardiac thrombus is achieved under deep hypothermic circulatory arrest, at a price of its non-physiological burden and time constraints. We propose a simple surgical manoeuvre enabling selective arch perfusion allowing for a milder hypothermia and liberal interval of circulatory arrest. METHODS On a routine cardiopulmonary bypass via median sternotomy, the dissection is extended along the aortic arch to identify the origins of the supra-aortic vessels. After standard aortic cross-clamping and cardioplegic cardiac arrest at moderate hypothermia, a second cross-clamp is applied at the aortic arch beyond the left carotid artery. A selective closed aortic arch perfusion is started while the extirpation of the tumour thrombus from the right atriotomy and abdominal cavotomy is being performed under conditions of circulatory arrest. RESULTS Using selective aortic arch perfusion, successful and uncomplicated extirpation of voluminous caval and intracardiac tumour thrombi was accomplished in 3 presented patients. Unexpectedly difficult thrombus adhering to hepatic veins in 1 patient required 42 min of circulatory arrest. Postoperative courses were uneventful in all 3 patients. CONCLUSIONS Second aortic cross-clamp to start selective closed aortic arch perfusion provides excellent surgical control of the operative field over a liberal time interval during circulatory arrest under milder hypothermia.

The susceptibility to fosfomycin of Gram-negative bacteria isolates from urinary tract infection in the Czech Republic: data from a unicentric study

BackgroundAgainst a background of rapid increase of β-lactamase-producing or multi-resistant pathogenic bacteria and the resulting lack of effective antibiotic treatment, some older antibiotics have been tested for new therapeutic uses. One of these is fosfomycin, to which according to studies these resistant bacteria are very sensitive. Our study was designed because there is no data on the fosfomycin susceptibility rate in the Czech Republic.MethodIn this study from January 2013 to June 2014 3295 unique isolates of Gram-negative bacteria which had caused urinary tract infections were examined. The antibiotic susceptibility was measured by disk diffusion test. Both EUCAST and CLSI guidelines criteria (for fosfomycin only) were used for the antibiotic susceptibility evaluation.ResultsThe most frequently tested bacterial isolates were Escherichia coli (51.3%, n = 1703), Klebsiella pneumoniae (19.4%, n = 643) and Proteus spp. (11.8%, n = 392). Among all isolates 29.0% (n = 963) were resistant to fluoroquinolones, 11.3% (n = 374) produced extended spectrum β-lactamase and 4.2% (n = 141) produced AmpC β-lactamase. The overall in vitro susceptibility was significantly higher for fosfomycin compared to the other tested per-oral antibiotics (nitrofurantoin, ampicillin, co-trimoxazole, ciprofloxacin and cefuroxime) against all tested Gram-negative rod isolates (excluding Morganella morgani and Acinetobacter spp. isolates). Fosfomycin also remained highly active against those isolates with extended spectrum β-lactamase (ESBL) production (95.8% in Escherichia coli isolates and 85.3% in Klebsiella pneumoniae isolates), unlike other tested per-oral antibiotics, which showed significant (p < 0.0001) susceptibility decrease.ConclusionWe have confirmed in the Czech Republic the very high susceptibility to fosfomycin trometamol of urinary tract infection pathogens, particularly Gram-negative rods including those producing β-lactamase.