Comparative analysis of the absorbed dose in the heart and anterior descending branch of the left coronary artery (LAD) in patients with left-sided breast cancer who received radiotherapy using 3D-CRT, IMRT and VMAT techniques.

PURPOSE: The purpose of this study was to compare the absorbed dose distributions within the heart and lad in patients with left-sided breast cancer who underwent radiotherapy using 3D-CRT, IMRT and VMAT techniques. METHODS: The treatment plans of 11 patients with left-sided breast cancer were analyzed. All of the patients were irradiated in our facility with DIBH 3D-CRT. For all patients the plans in the IMRT (sliding window) and VMAT (Rapid Arc - Varian) techniques were prepared. Cumulative dose-volume histograms (DVH) were used to compare the dose distributions between the plans for each patient. Statistical analysis was carried out using the one-way ANOVA with repeated measurements and Tukey's post hoc test. RESULTS: The use of IMRT and VMAT techniques allowed for a better coverage of the PTV with 95% isodose and a more homogeneous dose distribution compared to the 3D-CRT technique. The use of dynamic technique (IMRT or VMAT) did not provide significant protection for OARs - only the dose absorbed in LAD was slightly lower. CONCLUSION: The use of 3D-CRT allows better protection of critical organs compared to other techniques, except for the dose in the lad artery which was the lowest in IMRT technique. exposure of large tissue volumes to so-called low radiation doses is undoubtedly a disadvantage of using dynamic techniques.

The use of hyaluronic acid hydrogel as a tumour bed marker in breast-conserving therapy.

PURPOSE: To evaluate usefulness of hyaluronic acid (HA) hydrogel as a tumour bed marker in breast conserving therapy (BCT). To analyze inter- (Inter-OV) and intraobserver (Intra-OV) variability of contouring boost target volume (CTVboost) in external beam radiotherapy (EBRT). MATERIALS AND METHODS: Thirty-two patients in the HA group and 30 patients in the control group with an early stage breast cancer were included in the study. During the surgery 1-3 ml of HA hydrogel was injected into breast to mark the tumour bed for every patient in the HA group. Moreover, surgical clips were placed underneath the lumpectomy cavity. Patients in the control group were marked only by metal markers. Three radiation oncologists delineated CTVboost twice for every patient. Three parameters were calculated to quantify contouring variability: coefficient of variation for volumes (COVV), center of mass displacement (CoMd) and conformity index (CI). RESULTS: There were no significant differences between mean values of COVV for HA and control group, neither for Intra-OV (0.14 vs 0.13) nor Inter-OV (0.19 vs 0.18) calculations. The mean CoMd were 6.1 mm and 9.1 mm for Inter-OV calculations and 3.9 mm and 6.4 mm for Intra-OV in the HA and the control group respectively. The mean CI for Intra-OV improved from 0.61 to 0.65 and from 0.47 to 0.56 for Inter-OV in the control and HA group respectively. CONCLUSION: HA hydrogel used as a tumour bed marker improves tumour bed visibility and reduces inter- and intraobserver variability of EBRT boost target volume delineations.

The effect of radiotherapy and hormone therapy on osteopontin concentrations in prostate cancer patients.

PURPOSE: To evaluate and compare plasma osteopontin (OPN, a candidate prostate cancer biomarker) levels in prostate cancer patients receiving radiotherapy or combined radiotherapy or hormone therapy. METHODS: OPN levels were determined by ELISA in 40 prostate cancer patients eligible for radiotherapy (n=18 radiotherapy alone, n=22 combined radiotherapy and hormone therapy) before the start of irradiation, during treatment, and one month after its completion. RESULTS: OPN levels were significantly higher (p=0.02) in prostate cancer patients after receiving radiotherapy compared to baseline. In a subgroup analysis, there were no differences in OPN levels before and after treatment in patients undergoing radiotherapy alone, but OPN levels were significantly higher in patients after radiotherapy with hormone therapy compared to baseline (p=0.04) and in patients during radiotherapy compared to baseline (p=0.03). CONCLUSIONS: Radiotherapy can increase plasma OPN concentrations in patients with prostate cancer, and radiotherapy may interact with hormone therapy to increase OPN concentrations. These differences suggest that OPN is worthy of further study as a predictive biomarker.

Visualization of dose distribution in intraoperative electron beam Radiotherapy based on ultrasound images.

PURPOSE: The purpose of this study was to develop a method for dose distribution visualization in the case of Electron Beam Intraoperative Radiotherapy based on the images obtained in the operating room. This cannot be relied on CT images obtained before surgery due to significant tissue deformation. METHODS: The ultrasound scanning is the only method to obtain 3-dimensional (3D) reconstruction of a patient's tissue under operating room conditions. We decided to apply this modality as a background to visualize 3D dose distribution in terms of intraoperative radiotherapy (IORT). Dose distribution was obtained on the basis of dosimetric measurements carried out in the water phantom (PDD curves, transversal profiles). RESULTS: The method which has been developed in our department helps optimize the treatment. The amount of information depends strongly on the quality of the ultrasound image. We have verified the method (spatial correctness of dose painting) using commercially available phantom typically used for performance and quality assurance in ultrasound imaging (CIRS) and we noticed good correlation between 3D dose distribution and ultrasound image. CONCLUSIONS: Using up-to-date ultrasound tissue images allows better treatment optimization compared to the previous method that uses pre-surgery scans (CT or MRI). It helps optimize the angle of the beam axis and choose the beam with adequate range (energy) and avoid the risk of inaccurate irradiation of the area of interest.

Osteopontin And Angiogenic Factors As New Biomarkers Of Prostate Cancer.

PURPOSE: The novel biomarkers that would identify patients at risk for relapse and metastatic spread are needed. The aim of this study was the evaluation of serum levels of osteopontin (OPN) and tumor endogenous angiogenic factors such as vascular-endothelial growth factor (VEGF), vascular-endothelial growth factor receptor 2 (VEGF R2), endostatin, angiostatin and thrombospondin 1, in prostate cancer (PC) patients. MATERIAL AND METHODS: Blood concentrations of the analyzed parameters were determined in 40 prostate cancer patients eligible for radiotherapy as well as in the control group consisted of 25 volunteers. Commercial ELISA kits were used for the analysis. RESULTS: Significantly higher levels of OPN (101.49 ng/mL vs 59.88 ng/mL; P<.001), endostatin (252.60 ng/mL vs. 223.55 ng/mL; P=.043), angiostatin (47 ng/mL vs. 13 ng/mL; P=.047), VEGF (262.1 pg/mL vs. 138.0 pg/mL; P=.056) and VEGF R2 (11188.81 pg/mL vs. 9377.50 pg/mL; P=.047) were detected in PC patients compared with the control group. In PC patients we showed a positive correlation between OPN level and TNM clinical stage(R=0.36; P=.02) and negative correlation between OPN level and hemoglobin concentration (R=-0.33; P=.04). CONCLUSION: The study showed higher levels of the angiogenic factors in PC patients compared with the control group and identified OPN as an indicator of the PC clinical stage as well as a decreased hemoglobin level.

The analysis of the long-term outcomes in elderly women treated for locally advanced cervical cancer.

PURPOSE: Locally advanced cervical cancer (LACC) should be treated with a combination of external irradiation and brachytherapy with concurrent chemotherapy. However, as cervical carcinoma cells can disperse by way of the lymphatic system to either pelvic or para-aortic nodes, planning the extent of radiation requires precise information about the spread of the disease to the lymph nodes, especially to the para-aortic area. MATERIAL AND METHODS: All of the 75 women included in our study underwent chemoradiotherapy, which started with brachytherapy. Out of them, 54 have undergone radical hysterectomy with lymphadenectomy followed by chemoradiation. We have retrospectively analyzed the 5-year overall survival (OS) rates relative to the lymph node involvement, the type of lymphadenectomy performed (pelvic, para-aortic, or both), the size of the tumor (> or < 4 cm), the histological type, grading, and the age of patients. RESULTS: We observed significant differences in the OS rates relative to the age of the patients with LACC. We noted significant differences in the OS rates related to para-aortic lymphadenectomy and presence of lymph node metastases. CONCLUSIONS: Para-aortic lymphadenectomy seems to have a positive influence on long-term outcomes in the LACC patients, and elderly patients may benefit more from applied therapy.

15O-H2O PET/CT as a tool for the quantitative assessment of early post-radiotherapy changes of heart perfusion in breast carcinoma patients.

OBJECTIVE: Studies examining radiation-induced heart toxicity in breast cancer patients are inconclusive. The aim of this study was to prospectively and quantitatively asses myocardial blood flow (MBF) with, for the first time, 15O-H2O PET/CT as a marker of heart damage in irradiated breast cancer patients. METHODS: 15 breast cancer patients receiving intact breast or chest wall irradiation were included in the analysis (six with right-sided and nine with left-sided breast cancer). They underwent 15O-H2O PET/CT before radiotherapy (RT) and 2 and 8 months after RT. MBF was quantitatively assessed at rest and under stress conditions in 17 heart segments distinguished according to the American Ultrasound Association classification. Regional MBF values were derived in each of the coronary artery territories. RESULTS: MBF decreased in 53% and increased in 33% of cases 2 months after RT in both left-sided and right-sided breast cancer patients. Stress testing was more sensitive than at-rest testing, demonstrating decreased perfusion in the segments supplied by the left anterior descending coronary artery (LAD) [5.41 ± 1.74 vs 4.52 ± 1.82 ml (g*min)-1; p = 0.018], which persisted at 6 months [5.41 ± 1.74 vs 4.40 ± 1.38 ml (g*min)-1; p = 0.032] and a decrease in global heart perfusion [5.14 ± 1.49 vs 4.46 ± 1.73 ml (g*min)-1; p = 0.036]. A minimal radiation dose applied to the LAD correlated with MBF changes observed 2 months after RT (r = -0.57; p = 0.032). Radiological findings were not correlated with clinical symptoms of heart toxicity. CONCLUSION: 15O-H2O PET/CT is safe and effective for the early detection and quantitative analysis of subclinical post-RT changes in heart perfusion in breast cancer patients. The LV segments supplied by the LAD are the main site of MBF changes. A minimum radiation dose deposited in the LAD may be a predictor of radiation-induced heart toxicity. Advances in knowledge: This is the first time that 15O-H2O PET/CT has been used to assess MBF after RT and the first granular description of the distribution of blood flow changes after breast cancer RT.

Evaluation of Brain Edema Formation Defined By MRI After LINAC-based Stereotactic Radiosurgery.

BACKGROUND: Peri-lesional edema is a serious and well-known complication of stereotactic radiosurgery (SRS). Here we evaluated edema risk after SRS and assessed its formation and resolution dynamics. PATIENTS AND METHODS: 107 patients underwent SRS for heterogeneous diagnoses: 34 (29%) with arteriovenous malformations, 38 (35%) with meningiomas, 16 (15%) with metastatic tumors, 16 (15%) with acoustic neuromas, 3 with (3%) cavernomas, and 2 (2%) each with anaplastic astrocytomas and anaplastic oligoastrocytomas. Edema area was delineated in MRI T2-FLAIR sequences 0, 6, 12, 18, 24, 30, and 38 months after treatment. Lesion location was defined as either above (n = 80) or below (n = 32) the "Frankfurt modified line" (FML). RESULTS: 17% of patients developed or had worsening post-treatment edema. Edema volume was maximal at 6 months (mean 7.2, SD 1.2) post radiosurgery. Post-SRS edema was 5.1 (1.06 - 24.53) times more likely in patients with lesions above the FML. There was no association between edema development and age, PTV size, number of beams, and diagnosis (p = 0.07). CONCLUSIONS: Radiosurgery-associated edema develops within 6 months of treatment and decreases over time. Edema occurrence is strongly related to lesion location, and its presence is much more likely when the treated lesions are situated above the Frankfurt line.

Relationship between Glioblastoma Dose Volume Parameters Measured by Dual Time Point Fluoroethylthyrosine-PET and Clinical Outcomes.

Glioblastoma multiforme (GBM) is highly invasive. Despite irradiation with wide margins, GBM usually recurs in-field. Recent in vitro data have suggested that progression might be promoted by sublethal irradiation. Fluoroethylthyrosine-PET (FET-PET) can be used to detect glioblastoma invasion not apparent on MRI. We therefore performed a retrospective analysis of a prospective clinical study to examine whether glioblastoma outcomes depend on dose volume parameters measured by MRI and FET-PET. Twenty-three patients were prospectively recruited to a study examining the role of dual time point FET-PET in the treatment planning of GBM radiotherapy. The dose delivered to the site of recurrence was subdivided into suboptimal-dose (SOD) and high-dose (HD) areas. Types of progression were defined for correlation with dosimetric parameters including V100% of gross tumor volume (GTV)PET, GTVPETMRI, and GTVMRI. The HD area did not cover the entire GTVPETMRI in any case. Recurrences were significantly more frequent in the SubD area (chi-squared test, p = 0.004). There was no relationship between increasing dose volume and progression. The V100% for GTVPET and progression-free survival (PFS) was positively correlated (Spearman's rho 0.417; p = 0.038). Progression is more common in areas with suboptimal dosing. Dose heterogeneity within GTVPET may be responsible for shorter PFS.

Pre-irradiation tumour volumes defined by MRI and dual time-point FET-PET for the prediction of glioblastoma multiforme recurrence: A prospective study.

BACKGROUND AND PURPOSE: The diagnostic accuracy of magnetic resonance imaging (MRI) for glioblastoma multiforme (GBM) is suboptimal. We analysed pre-treatment MRI- and dual time-point 18F-fluoroethylthyrosine-PET (FET-PET)-based target volumes and GBM recurrence patterns following radiotherapy with temozolomide. MATERIALS AND METHODS: Thirty-four patients with primary GBM were treated according to MRI-based treatment volumes (GTVRM). Patients underwent dual time-point FET-PET scans prior to treatment, and biological tumour volumes (GTVPET) were contoured but not used for target definition. Progressions were classified based on location of primary GTVs. Volume and uniformity of MRI- vs. FET-PET/CT-derived GTVs and progression patterns assessed by MRI were analysed. RESULTS: FET-based GTVs measured 10min after radionuclide injection (a.r.i.; median 37.3cm(3)) were larger than GTVs measured 60min a.r.i. (median 27.7cm(3)). GTVPET volumes were significantly larger than corresponding MRI-based GTVs. MRI and PET concordance for the identification of glioblastoma GTVs was poor (mean uniformity index 0.4). 74% of failures were inside primary GTVPET volumes, with no solitary progressions inside the MRI-defined margin +20mm but outside the GTVPET detected. CONCLUSIONS: The size and geometry of GTVs differed in the majority of patients. The GTVPET volume depends on time after radionuclide injection. FET-PET better defined failure site than MRI alone.

Whole breast irradiation vs. APBI using multicatheter brachytherapy in early breast cancer - simulation of treatment costs based on phase 3 trial data.

PURPOSE: A recent large phase 3 trial demonstrated that the efficacy of accelerated partial-breast irradiation (APBI) in the treatment of early breast cancer is non-inferior to that of whole breast irradiation (WBI) commonly used in this indication. The aim of this study was to compare the costs of treatment with APBI and WBI in a population of patients after conserving surgery for early breast cancer, and to verify if the use of APBI can result in direct savings of a public payer. MATERIAL AND METHODS: The hereby presented cost analysis was based on the results of GEC-ESTRO trial. Expenditures for identified cost centers were estimated on the basis of reimbursement data for the public payer. After determining the average cost of early breast cancer treatment with APBI and WBI over a 5-year period, the variance in this parameter resulting from fluctuations in the price per single procedure was examined on univariate sensitivity analysis. Then, incremental cost-effectiveness ratio (ICER) was calculated to verify the cost against clinical outcome. Finally, a simulation of public payer's expenditures for the treatment of early breast cancer with APBI and WBI in 2013 and 2025 has been conducted. RESULTS: The average cost of treatment with APBI is lower than for WBI, even assuming a potential increase in the unit price of the former procedure. There was no additional health benefit of WBI and the calculation of cost-effectiveness was based on the absolute difference in overall local control rate. However, this difference (0.92% vs. 1.44%) was fairly minimal and was not identified as statistically significant during 5 years. CONCLUSIONS: The use of APBI as an alternative to WBI in the treatment of early breast cancer would substantially reduce healthcare expenditures in both 2013 and 2025, even assuming an increase in the price per single APBI procedure.

Transition from Paris dosimetry system to 3D image-guided planning in interstitial breast brachytherapy.

PURPOSE: The purpose of this study is to evaluate our first experience with 3D image-guided breast brachytherapy and to compare dose distribution parameters between Paris dosimetry system (PDS) and image-based plans. MATERIAL AND METHODS: First 49 breast cancer patients treated with 3D high-dose-rate interstitial brachytherapy as a boost were selected for the study. Every patient underwent computed tomography, and the planning target volume (PTV) and organs at risk (OAR) were outlined. Two treatment plans were created for every patient. First, based on a Paris dosimetry system (PDS), and the second one, imaged-based plan with graphical optimization (OPT). The reference isodose in PDS implants was 85%, whereas in OPT plans the isodose was chosen to obtain proper target coverage. Dose and volume parameters (D90, D100, V90, V100), doses at OARs, total reference air kerma (TRAK), and quality assurance parameters: dose nonuniformity ratio (DNR), dose homogeneity index (DHI), and conformity index (COIN) were used for a comparison of both plans. RESULTS: The mean number of catheters was 7 but the mean for 20 first patients was 5 and almost 9 for the next 29 patients. The mean value of prescribed isodose for OPT plans was 73%. The mean D90 was 88.2% and 105.8%, the D100 was 59.8% and 75.7%, the VPTV90 was 88.6% and 98.1%, the VPTV100 was 79.9% and 98.9%, and the TRAK was 0.00375 Gym(-1) and 0.00439 Gym(-1) for the PDS and OPT plans, respectively. The mean DNR was 0.29 and 0.42, the DHI was 0.71 and 0.58, and the COIN was 0.68 and 0.76, respectively. CONCLUSIONS: The target coverage in image-guided plans (OPT) was significantly higher than in PDS plans but the dose homogeneity was worse. Also, the value of TRAK increased because of change of prescribing isodose. The learning curve slightly affected our results.

Dose estimation for different skin models in interstitial breast brachytherapy.

PURPOSE: Skin is a major organ at risk in breast-conserving therapy (BCT). The American Brachytherapy Society (ABS) recommendations require monitoring of maximum dose received, however, there is no unambiguous way of skin contouring provided. The purpose of this study was to compare the doses received by the skin in different models. MATERIAL AND METHODS: Standard treatment plans of 20 patients who underwent interstitial breast brachytherapy were analyzed. Every patient had a new treatment plan prepared according to Paris system and had skin contoured in three different ways. The first model, Skin 2 mm, corresponds to the dermatological breast skin thickness and is reaching 2 mm into an external patient contour. It was rejected in a further analysis, because of distinct discontinuities in contouring. The second model, Skin 4 mm, replaced Skin 2 mm, and is reaching 2 mm inside and 2 mm outside of the External contour. The third model, Skin EXT, is created on the External contour and it expands 4 mm outside. Doses received by the most exposed 0.1 cc, 1 cc, 2 cc, and the maximum doses for Skin 4 mm and Skin EXT were compared. RESULTS: Mean, median, maximum, and standard deviation of percentage dose difference between Skin EXT and Skin 4 mm for the most exposed 0.1 cc (D0.1cc) of skin were 18.01%, 17.20%, 27.84%, and 4.01%, respectively. All differences were statistically significant (p < 0.05). CONCLUSIONS: Monitoring of doses received by skin is necessary to avoid complications and obtain a satisfactory cosmetic effect. It is difficult to assess the compatibility of treatment plans with recommendations, while there is no unambiguous way of skin contouring. Especially, if a mean difference of doses between two models of skin contouring is 18% for the most exposed 0.1 cc and can reach almost 28% in some cases. Differences of this magnitude can result in skin complications during BCT.

Three-dimensional dosimetry of the full and empty bladder in high dose rate vaginal cuff brachytherapy.

OBJECTIVES: The objectives of the study were to assess the bladder doses during vaginal cuff brachytherapy and to examine the effect of bladder filling on normal tissue dosimetry by means of computed tomography. MATERIALS AND METHODS: A total number of 45 women were enrolled in a prospective clinical trial. Patients were treated with the application of a single-line source vaginal cylinder. All the patients were asked to consume 400 mL of water 40 minutes before computed tomography scans were taken. For each patient, 2 treatment plans were performed-one with full bladder and the other one when the bladder was emptied. A dose-volume histogram and the equivalent of 2-Gy dose for full and empty bladder were calculated. Doses to the bowels in 2 states of the bladder were estimated. RESULTS: Thirty-five patients received a lower dose to the empty bladder than to the filled organ. The average dose difference was 0.5 Gy. Ten patients received a lower dose to the full bladder than to the empty one. However, in this case, the difference amounted only to 0.2 Gy on average. Dose parameters (the maximal dose received by 0.1 cm of tissue and the maximal dose received by 2 cm of tissue) were lower in the empty state, but the volumetric parameters (the percent of bladder volume receiving ≥50% of the prescribed dose and the percent of bladder volume receiving ≥80% of the prescribed dose) were higher in the empty state of the bladder. Doses to the bowels seemed to be higher in the empty bladder. However, none of the doses exceeded the limitations. CONCLUSIONS: The results have shown that in most cases, the dose to the empty bladder is lower than when the bladder is full. Simultaneously, the doses to the bowels increase proportionally in the empty state of the bladder comparing to the full organ. Protection of the bowels, which are more radiosensitive, suggests treating the patients in the full state of the bladder. Early and late bowel toxicity should be investigated to establish clear standards of treatment.

Preliminary results of linac-based radiosurgery in arteriovenous malformations and cerebral tumours in the Oncology Centre in Bydgoszcz.

AIM OF THE STUDY: Efficacy of stereotactic radiosurgery (SRS) in the treatment in cerebral AVM's, mennigiomas, metastases, acoustic neuromas and recurrent anaplastic gliomas is well documented. The object of this work was the analysis of the results of the treatment of AVM and selected cerebral lesions with linear accelerator-based stereotactic radiosurgery. MATERIAL AND METHODS: THE LESIONS INCLUDED: 12 AVMs, 2 cavernomas, 27 meningiomas, 16 metastases, 5 acoustic neuromas, 16 gliomas in 78 patients. A mean radiation dose of 16Gy was delivered to the tumour or AVM margin and 12Gy to the tumours located in a ponto-cerebellar angle. Follow-up was 18 months. RESULTS: Control of tumour growth or AVM was achieved in all cases after 6 months and radiological regression was observed in 20 cases after 12 months. The best results were noted in AVM's, meningiomas and neuromas.There were no new permanent deficits nor complications after radiosurgery requiring medicamentation. CONCLUSIONS: Organization of SRS in Oncological Center in Bydgoszcz involving close co-operation of radiotherapist, neurosurgeon and physicist in the process of qualification and treatment planning is based on the best global standards. Preliminary results of treatment are consistent with the literature data. A longer follow-up is required to determine the long term efficacy and the toxicity of this treatment in our institution.

Measurement of primary tumor volume by PET-CT to evaluate risk of mediastinal nodal involvement in NSCLC patients with clinically negative N2 lymph nodes.

AIM: The study aimed to determine a prognostic value of primary tumor volume measured on the basis of integrated positron emission tomography-computerized tomography (PET-CT) in terms of mediastinal nodal metastases (N2) prediction in non-small-cell lung cancer (NSCLC) patients with PET-CT N2 negative lymph nodes. METHODS: The records of 70 potentially operable NSCLC patients treated with surgical resection were analyzed. All patients underwent diagnostic, preoperative PET-CT, which was the basis for tumor volume calculations as well as the evaluation of N2 nodes status. The logistic regression analysis was employed to determine correlation between mediastinal nodal involvement and volume of primary tumor (izoSUV2.5 volume), that is the volume of primary tumor inside SUV 2.5 line, tumor histology, location (peripheral vs. central), hilar node status. RESULTS: A statistically significant correlation between mediastinal node involvement and izoSUV2.5 volume, tumor histology, locations peripheral vs. central and hilar node status was found. The risk of mediastinal lymph node metastasis is 24% for tumor volume of 100 cm(3) and increases up to 40% for tumor volume of 360 cm(3). An increase of tumor volume by 1 cm(3) increases the risk of lymph node disease by 0.3%. Tumor histology adenocarcinoma vs. squamous cell carcinoma increases the risk of mediastinal lymph node involvement by 195%, location central vs. peripheral by 68% and hilar node involvement by 166%. CONCLUSIONS: The study demonstrates that izoSUV2.5 volume of primary tumor may be considered as a prognostic factor in NSCLC patients, since it strongly correlates with mediastinal lymph node pathological status. This correlation is modified by primary tumor location, histology and hilar node involvement.

Indications for postoperative radiotherapy in patients with prostate cancer after surgery with positive surgical margins.

AIM OF THE STUDY: Prostate cancer is the second most prevalent cancer among men in Poland. The main methods of radical treatment are radical prostatectomy and radiotherapy. In patients who have been correctly qualified for surgery, a positive surgical margin is always an unexpected and undesirable factor. The aim of this prospective study was to evaluate the incidence of positive margins in more than 100 consecutive patients with prostate cancer undergoing radical prostatectomy. MATERIAL AND METHODS: The study included 114 patients aged 44-78 years (mean 61.5 years) who underwent surgery for prostate cancer in stage cT1-3N0/M0 (according to the TNM staging system) in the years 2010-2011 in the Clinical Department of Oncological Urology in the Center of Oncology in Bydgoszcz. RESULTS: The presence of positive surgical margins was found in 45 (39.47%) patients, and in 20 (17.54%) margins were assessed as close (1-2 mm). Among the patients with positive surgical margins about 22% had biochemical recurrence. Among patients with negative surgical margins 13% of pT2c and 12.5% of pT3a had biochemical recurrence. Patients with positive surgical margins, along with patients diagnosed with tumor extending beyond the prostate (pT3a) or invading seminal vesicles (pT3b), are at an increased risk of recurrence and progression, reaching up to 30-50% over 10 years. The risk is 2-4 times higher than in patients without positive operating margins.

Time-dependent changes of plasma concentrations of angiopoietins, vascular endothelial growth factor, and soluble forms of their receptors in nonsmall cell lung cancer patients following surgical resection.

Even when patients with nonsmall cell lung cancer undergo surgical resection at an early stage, recurrent disease often impairs the clinical outcome. There are numerous causes potentially responsible for a relapse of the disease, one of them being extensive angiogenesis. The balance of at least two systems, VEGF VEGFR and Ang Tie, regulates vessel formation. The aim of this study was to determine the impact of surgery on the plasma levels of the main angiogenic factors during the first month after surgery in nonsmall cell lung cancer patients. The study group consisted of 37 patients with stage I nonsmall cell lung cancer. Plasma concentrations of Ang1, Ang2, sTie2, VEGF, and sVEGF R1 were evaluated by ELISA three times: before surgical resection and on postoperative days 7 and 30. The median of Ang2 and VEGF concentrations increased on postoperative day 7 and decreased on day 30. On the other hand, the concentration of sTie2 decreased on the 7th day after resection and did not change statistically later on. The concentrations of Ang1 and sVEGF R1 did not change after the surgery. Lung cancer resection results in proangiogenic plasma protein changes that may stimulate tumor recurrences and metastases after early resection.

Oxidative stress markers in prostate cancer patients after HDR brachytherapy combined with external beam radiation.

Assessment of oxidative stress markers was perfomed in prostate cancer (PCa) patients subjected to high-dose brachytherapy (HDR) with external beam radiotherapy (EBRT). Sixty men with PCa were subjected to combined two-fraction treatment with HDR (tot. 20 Gy) and EBRT (46 Gy). Blood samples were taken before treatment, immediately afterwards, after 1.5-3 months, and approx. 2 years. Control group consisted of 30 healthy men. Erythrocyte glutathione peroxidase activity in the patients was lower than in healthy subjects by 34% (P < 0.001), 50% (P < 0.001), 30% (P < 0.05), and 61% (P < 0.001), respectively, at all periods. No significant differences were found by comparing superoxide dismutase and catalase activity in PCa patients with that of the controls. After 2 years of the end of treatment, the activity of studied enzymes demonstrated a decreasing tendency versus before therapy. Blood plasma thiobarbituric acid reactive substances (TBARS) concentration was higher than in the controls at all periods, while erythrocyte TBARS decreased after 2 years to control levels. The results confirm that in the course of PCa, imbalance of oxidant-antioxidant processes occurs. The therapy did not alter the levels of oxidative stress markers, which may prove its applicability. Two years is too short a period to restore the oxidant-antioxidant balance.