[CyberKnife for prostate cancer patients. Update of 200 patients treatment results].

Introduction: This is an update regarding the treatment results of 200 prostate cancer patients' (PCP) CyberKnife based radioablation (the first group in Poland). The purpose of this study is reevaluation (after 2 years) of this treatment modality results of low (LR) and intermediate risk (IR) (including T2c) PCP and failure analysis. Material and Methods: 200 PCP (95 LR, 86 IR, 19 T2c) 53 ­ 83 y.o. (mean 69) treated between 2011 and 2014. 48% used neoadjuvant ADT. The patients were irradiated every other day with a fraction dose of 7.25 Gy to the total dose 36.25 Gy (5 fractions in 9 days). Fiducials based tracking was performed. The patients were controlled on the treatment completion day, 1, 4, 8 months later and subsequently every 6 months. The PSA concentration, ADT usage, acute and late adverse effects (EORTC/RTOG) and other symptoms were evaluated. FU ranged from 1 to 63.6 months (mean 32.2, median 32.9). Results: The adverse effects percentage was very low; only 1 month after treatment the percentage of acute urinary reaction exceeded 40%. Only single G3 adverse effects were noted. Over 4 months the median PSA concentration declined from 3.75 to 0.27 ng/ml. 9 failures (4.5%) were noted ­ more among IR and patients without neoadjuvant ADT. No failure in the T2c group was found. Median time to failure was 32.4 months. Cox analysis revealed that the failure risk increases with the value of maximal PSA before treatment. Conclusions: CK based radioablation of LR and IR PCP is a safe and highly effective treatment modality. The main prognostic factor of failure after this treatment is probably the maximal PSA concentration before treatment. The neoadjuvant ADT in IR group should be considered. The lack of failures in the T2c group enables us to suggest that even more locally advanced patients (T3) with low PSA and maximal Gleason 3+4 could be treated with this modality.

Identification of serum proteome signatures of locally advanced and metastatic gastric cancer: a pilot study.

BACKGROUND: The gastric cancer is one of the most common and mortal cancer worldwide. The initial asymptomatic development and further nonspecific symptoms result in diagnosis at the advanced stage with poor prognosis. Yet, no clinically useful biomarkers are available for this malignancy, and invasive gastrointestinal endoscopy remains the only reliable option at the moment. Hence, there is a need for discovery of clinically useful noninvasive diagnostic and/or prognostic tool as an alternative (or complement) for current diagnostic tools. Here we aimed to search for serum proteins characteristic for local and invasive gastric cancer. METHODS: Pre-treatment blood samples were collected from patients with diagnosed gastric adenocarcinoma at the different stage of disease: 35 patients with locally advanced cancer and 18 patients with metastatic cancer; 50 healthy donors were also included as a control group. The low-molecular-weight fraction of serum proteome (i.e., endogenous peptidome) was profiled by the MALDI-ToF mass spectrometry, and the whole proteome components were identified and quantified by the LC-MS/MS shotgun approach. RESULTS: Multicomponent peptidome signatures were revealed that allowed good discrimination between healthy controls and cancer patients, as well as between patients with locally advanced and metastatic cancer. Moreover, a LC-MS/MS approach revealed 49 serum proteins with different abundances between healthy donors and cancer patients (predominantly proteins associated with inflammation and acute phase response). Furthermore, 19 serum proteins with different abundances between patients with locally advanced and metastatic cancer were identified (including proteins associated with cytokine/chemokine response and metabolism of nucleic acids). However, neither peptidome profiling nor shotgun proteomics approach allowed detecting serum components discriminating between two subgroups of patients with local disease who either developed or did not develop metastases during follow-up. CONCLUSIONS: The molecular differences between locally advanced and metastatic gastric cancer, as well as more obvious differences between healthy individuals and cancer patients, have marked reflection at the level of serum proteome. However, we have no evidence that features of pre-treatment serum proteome could predict a risk of cancer dissemination in patients treated due to local disease. Nevertheless, presented data confirmed potential applicability of a serum proteome signature-based biomarker in diagnostics of gastric cancer.

Re-irradiation for intra-thoracic tumours and extra-thoracic breast cancer: dose accumulation, evaluation of efficacy and toxicity based on a literature review.

The improvement seen in the diagnostic procedures and treatment of thoracic tumours means that patients have an increased chance of longer overall survival. Nevertheless, we can still find those who have had a recurrence or developed a secondary cancer in the previously treated area. These patients require retreatment including re-irradiation. We have reviewed the published data on thoracic re-irradiation, which shows that some specific healthy tissues can tolerate a significant dose of irradiation and these patients benefit from aggressive treatment; however, there is a risk of damage to normal tissue under these circumstances. We analysed the literature data on re-irradiation in the areas of vertebral bodies, spinal cord, breast, lung and oesophagus. We evaluated the doses of primary and secondary radiotherapy, the treatment techniques, as well as the local control and median or overall survival in patients treated with re-radiation. The longest OS is reported in the case of re-irradiation after second breast-conserving therapy where the 5-year OS range is 81 to 100% and is shorter in patients with loco-reginal re-irradiation where the 5-y OS range is 18 to 60%. 2-year OS in patients re-irradiated for lung cancer and oesophagus cancer range from 13 to 74% and 18 to 42%, respectively. Majority grade ≥3 toxicity after second breast-conserving therapy was fibrosis up to 35%. For loco-regional breast cancer recurrences, early toxicity occurred in up to 33% of patients resulting in mostly desquamation, while late toxicity was recorded in up to 23% of patients and were mostly ulcerations. Early grade ≥3 lung toxicity developed in up to 39% of patients and up to 20% of Grade 5 hemoptysis. The most frequently observed early toxicity grade ≥3 in oesophageal cancer was oesophagitis recorded in up to 57% of patients, followed by hematological complications which was recorded in up to 50% of patients. The most common late complications included dysphagia, recorded in up to 16.7% of patients. We have shown that thoracic re-irradiation is feasible and effective in achieving local control in some patients. Re-irradiation should be performed with maximum accuracy and care using the best available treatment methods with a highly conformal, image-guided approach. Due to tremendous technological progress in the field of radiotherapy, we can deliver radiation precisely, shorten the overall treatment time and potentially reduce treatment-related toxicities.

The Prognostic Value of PI-RADS Score in CyberKnife Ultra-Hypofractionated Radiotherapy for Localized Prostate Cancer.

Prostate Imaging-Reporting and Data System (PI-RADS) has been widely implemented as a diagnostic tool for significant prostate cancer (PCa); less is known about its prognostic value, especially in the setting of primary radiotherapy. We aimed to analyze the association between PI-RADS v. 2.1 classification and risk of metastases, based on a group of 152 patients treated with ultra-hypofractionated stereotactic CyberKnife radiotherapy for localized low or intermediate risk-group prostate cancer. We found that all distant failures (n = 5) occurred in patients diagnosed with a PI-RADS score of 5, and axial measurements of the target lesion were associated with the risk of developing metastases (p < 0.001). The best risk stratification model (based on a combination of greatest dimension, the product of multiplication of PI-RADS target lesion axial measurements, and age) achieved a c-index of 0.903 (bootstrap-validated bias-corrected 95% CI: 0.848−0.901). This creates a hypothesis that PI-RADS 5 and the size of the target lesion are important prognostic factors in early-stage PCa patients and should be considered as an adverse prognostic measure for patients undergoing early treatment such as radiation or focal therapy.

Ultra-Hypofractionated Stereotactic Body Radiotherapy for Localized Prostate Cancer: Clinical Outcomes, Patterns of Recurrence, Feasibility of Definitive Salvage Treatment, and Competing Oncological Risk.

A cohort of 650 patients treated for localized prostate cancer (PCa) with CyberKnifeTM ultra-hypofractionated radiotherapy between 2011 and 2018 was retrospectively analyzed in terms of survival, patterns of failure, and outcomes of second-line definitive salvage therapies. The analysis was performed using survival analysis including the Kaplan-Meier method and Cox regression analysis. At a median follow-up of 49.4 months, the main pattern of failure was local-regional failure (7.4% in low-, and 13% in intermediate/high-risk group at five years), followed by distant metastases (3.6% in low-, and 6% in intermediate/high-risk group at five years). Five-year likelihood of developing a second malignancy was 7.3%; however, in the vast majority of the cases, the association with prior irradiation was unlikely. The 5-year overall survival was 90.2% in low-, and 88.8% in intermediate/high-risk patients. The independent prognostic factors for survival included age (HR 1.1; 95% CI 1.07-1.14) and occurrence of a second malignancy (HR 3.67; 95% CI 2.19-6.15). Definitive local salvage therapies were feasible in the majority of the patients with local-regional failure, and uncommonly in patients with distant metastases, with an estimated second-line progression free survival of 67.8% at two years. Competing oncological risks and age were significantly more important for patients' survival compared to primary disease recurrence.

Dose-response with stereotactic body radiotherapy for prostate cancer: A multi-institutional analysis of prostate-specific antigen kinetics and biochemical control.

BACKGROUND AND PURPOSE: The optimal dose for prostate stereotactic body radiotherapy (SBRT) is still unknown. This study evaluated the dose-response relationships for prostate-specific antigen (PSA) decay and biochemical recurrence (BCR) among 4 SBRT dose regimens. MATERIALS AND METHODS: In 1908 men with low-risk (50.0%), favorable intermediate-risk (30.9%), and unfavorable intermediate-risk (19.1%) prostate cancer treated with prostate SBRT across 8 institutions from 2003 to 2018, we examined 4 regimens (35 Gy/5 fractions [35/5, n = 265, 13.4%], 36.25 Gy/5 fractions [36.25/5, n = 711, 37.3%], 40 Gy/5 fractions [40/5, n = 684, 35.8%], and 38 Gy/4 fractions [38/4, n = 257, 13.5%]). Between dose groups, we compared PSA decay slope, nadir PSA (nPSA), achievement of nPSA ≤0.2 and ≤0.5 ng/mL, and BCR-free survival (BCRFS). RESULTS: Median follow-up was 72.3 months. Median nPSA was 0.01 ng/mL for 38/4, and 0.17-0.20 ng/mL for 5-fraction regimens (p < 0.0001). The 38/4 cohort demonstrated the steepest PSA decay slope and greater odds of nPSA ≤0.2 ng/mL (both p < 0.0001 vs. all other regimens). BCR occurred in 6.25%, 6.75%, 3.95%, and 8.95% of men treated with 35/5, 36.25/5, 40/5, and 38/4, respectively (p = 0.12), with the highest BCRFS after 40/5 (vs. 35/5 hazard ratio [HR] 0.49, p = 0.026; vs. 36.25/5 HR 0.42, p = 0.0005; vs. 38/4 HR 0.55, p = 0.037) including the entirety of follow-up, but not for 5-year BCRFS (≥93% for all regimens, p ≥ 0.21). CONCLUSION: Dose-escalation was associated with greater prostate ablation and PSA decay. Dose-escalation to 40/5, but not beyond, was associated with improved BCRFS. Biochemical control remains excellent, and prospective studies will provide clarity on the benefit of dose-escalation.

Polyostotic sclerosing histiocytosis (Erdheim-Chester disease) treated with combined vertebroplasty and radiation therapy.

Erdheim-Chester disease is an uncommon form of non-Langherans-cell histiocytosis, with a heterogeneous range of systemic manifestations and a pattern of typical clinico-pathological and radiological features. Symmetric sclerotic radiological alterations of the long bones are peculiar, such as the infiltration of several organs by lipid-laden histiocytes. Radiation therapy has been anecdotally employed in a palliative setting in order to relieve symptoms mainly due to cerebral, retro-orbital and skeletal localizations. Exclusive osseous involvement is rarely described in the medical literature. Moreover, the role, timing and schedule of radiotherapy in this subset of patients remain controversial. We herein report on a case of osseous-only Erdheim-Chester disease treated with a combined modality approach including transoral vertebroplasty and external beam radiation therapy, which gave an analgesic effect that lasted 1 year, with no treatment-related side effects.

Prostate-specific antigen kinetics and biochemical control following stereotactic body radiation therapy, high dose rate brachytherapy, and low dose rate brachytherapy: A multi-institutional analysis of 3502 patients.

BACKGROUND AND PURPOSE: Stereotactic body radiation therapy (SBRT), low dose rate brachytherapy (LDR-BT) and high dose rate brachytherapy (HDR-BT) are ablative-intent radiotherapy options for prostate cancer (PCa). These vary considerably in dose delivery, which may impact post-treatment prostate-specific antigen (PSA) patterns and biochemical control. We compared PSA kinetics between SBRT, HDR-BT, and LDR-BT, and assessed their relationships to biochemical recurrence-free survival (BCRFS). METHODS AND MATERIALS: Retrospective PSA data were analyzed for 3502 men with low-risk (n = 2223; 63.5%), favorable intermediate-risk (n = 869; 24.8%), and unfavorable intermediate-risk (n = 410; 11.7%) PCa treated with SBRT (n = 1716; 49.0%), HDR-BT (n = 512; 14.6%), or LDR-BT (n = 1274; 36.4%) without upfront androgen deprivation therapy at 10 institutions from 1990 to 2017. We compared nadir PSA (nPSA), time to nPSA, achievement of nPSA <0.2 ng/mL and <0.5 ng/mL, rates of nPSA <0.4 ng/mL at 4 years, and BCRFS. RESULTS: Median follow-up was 72 months. Median nPSA and nPSA <0.2 ng/mL were stratified by risk group (interaction p ≤ 0.001). Median nPSA and time to nPSA were 0.2 ng/mL at 44 months after SBRT, 0.1-0.2 ng/mL at 37 months after HDR-BT, and 0.01-0.2 ng/mL at 51 months after LDR-BT (mean log nPSA p ≤ 0.009 for LDR-BT vs. SBRT or HDR-BT for low/favorable intermediate-risk). There were no differences in nPSA <0.4 ng/mL at 4 years (p ≥ 0.51). BCRFS was similar for all three modalities (p ≥ 0.27). Continued PSA decay beyond 4 years was predictive of durable biochemical control. CONCLUSION: LDR-BT led to lower nPSAs with longer continued decay compared to SBRT and HDR-BT, but no differences in BCRFS.

Stereotactic Ablative Radiotherapy for Prostate Cancer-The Treatment Results of 500 Patients and Analysis of Failures.

OBJECTIVE: Stereotactic ablative radiotherapy is a very promising approach for the treatment of patients with prostate cancer. The aim of this study was to evaluate the clinical tolerance, effectiveness, patterns of failure, and attempt to define predictive factors based on our experience. METHODS: The cohort consists of 264 low-risk and 236 intermediate-risk consecutive patients treated at one institution. Prostate-specific antigen (PSA), adverse effects, and androgen deprivation therapy (ADT) usage were noted. RESULTS: Median follow-up was 31.3 months. Over 90% of the patients reported no gastrointestinal toxicity. There were 4 occurrences of G3+ sequelae. 75% patients had no genitourinary toxicity at first month, and up to 90% during the rest of follow-up, with only 1 case of G3 adverse event. The toxicity was more pronounced in patients with higher PSA concentrations. Prior to stereotactic ablative radiotherapy, the mean PSA was 7.59 and 277 patients used ADT. The PSA decreased for up to 20 months before reaching a plateau. The decline was slower, and PSA levels were higher in patients without ADT. A total of 15 treatment failures occured in a median time of 19.9 months. Higher PSA concentrations were connected with higher failure rates, even in the first month and prior to reaching Phoenix criterion. CONCLUSION: CyberKnife-based stereotactic ablative radiotherapy of low-risk and intermediate-risk prostate cancer patients is an effective and well-tolerated modality of treatment. PSA is the most important predictive factor. The evolution of PSA concentration in a particular subgroup of patients suggests that ADT in intermediate-risk cases could improve long-term results.

The Correlation of Blood Parameters with Size in Cases of Neoplastic Tumor

Purpose: This study aimed to evaluate the impact of tumor volume on platelet counts (PLT) and mean platelet volume (MPV) and involve these parameters on overall survival. Methods: It is a retrospective study of 99 patients with lung cancer (confirmed histologically or cytologically). Sixty-six patients underwent radical operating treatment and 33 patients had only biopsies ­ due to the inoperable status of tumor According to the histopathology profile: non-small cell carcinoma ­ 23%, adenocarcinoma - 23 %, squamous - 36%, small cell carcinoma -11%, carcinoid ­ 6%. The overall survival was measured from the time of surgery to last observation or death. The tumor's size was established based on information from histopathology protocol by using model for the ellipsoid (V=4/3 π r abc). Results: KM median survival time after surgery was 20 months (95% C.I. = 16­42). The survival time depends significantly on: Tumor feature, MPV (p=0.03, p=0.04). Patients with normal PLT levels have longer survival time (median: 11 months) than thrombocytosis group (9.5) (p=0.6). Following both the PLT and MPV, a change-point that is equal to approximately 18.5 cm3 (approx. 3.3 cm in diameter) stands for a segmented relationship between tumor volume and analyzed blood indicators. Conclusions: After an overstepping of the change-point of tumor volume inflammatory processes start and they are associated with poor prognosis. MPV may be a valuable biomarker for the diagnosis and follow up of various types of carcinoma.

Multi-Institutional Analysis of Prostate-Specific Antigen Kinetics After Stereotactic Body Radiation Therapy.

PURPOSE: Understanding prostate-specific antigen (PSA) kinetics after radiation therapy plays a large role in the management of patients with prostate cancer (PCa). This is particularly true in establishing expectations regarding PSA nadir (nPSA) and PSA bounces, which can be disconcerting. As increasingly more patients are being treated with stereotactic body radiation therapy (SBRT) for low- and intermediate-risk PCa, it is imperative to understand the PSA response to SBRT. METHODS AND MATERIALS: PSA data from 5 institutions were retrospectively analyzed for patients with localized PCa treated definitively with SBRT alone from 2004 to 2016. Patients received 35 to 40 Gy in 5 fractions, per institutional standards. Patients who had less than 12 months of PSA data or received androgen deprivation therapy were excluded from this study. Linear and logistic multivariable analysis were performed to identify predictors of nPSA, bounce, and biochemical recurrence, and joint latent class models were developed to identify significant predictors of time to biochemical failure. RESULTS: A total of 1062 patients were included in this study. Median follow-up was 66 months (interquartile range [IQR], 36.4-89.9 months). Biochemical failure per the Phoenix criteria occurred in 4% of patients. Median nPSA was 0.2 ng/mL, median time to nPSA was 40 months, 84% of patients had an nPSA ≤0.5 ng/mL, and 54% of patients had an nPSA ≤0.2 ng/mL. On multivariable analysis, nPSA was a significant predictor of biochemical failure. Benign PSA bounce was noted in 26% of patients. The median magnitude of PSA bounce was 0.52 ng/mL (IQR, 0.3-1.0 ng/mL). Median time to PSA bounce was 18.1 months (IQR, 12.0-31.1 months). On multivariable analysis, age and radiation dose were significantly associated with a lower incidence of bounce. Joint latent class models modeling found that nPSA and radiation dose were significantly associated with longer time to biochemical failure. CONCLUSIONS: In this multi-institutional cohort of patients with long-term follow-up, we found that SBRT led to low nPSAs. In turn, lower nPSAs are associated with reduced incidence of, and longer time to, biochemical failure. Benign PSA bounces occurred in a quarter of patients, as late as several years after treatment. Further studies are needed to directly compare the PSA response of patients who receive SBRT versus other treatment modalities.

Moderately low alpha/beta ratio for rectal cancer may best explain the outcome of three fractionation schedules of preoperative radiotherapy.

PURPOSE: To estimate the alpha/beta ratio for rectal cancer according to the outcome of three fractionation schedules of preoperative radiotherapy. METHODS AND MATERIALS: Between 1996 and 2002, 168 patients with locally advanced rectal cancer were treated as follows: 53 patients received 25 Gy in 5 Gy per fraction, 45 received 30 Gy in 3.0 Gy per fraction, and 70 were treated with accelerated hyperfractionation (42 Gy, 1.5 Gy per fraction, given twice daily). No patients received concurrent chemotherapy. The clinical characteristics of the groups were comparable. Surgery was performed shortly after radiotherapy. Crude data on locoregional tumor control were fitted directly using a linear-quadratic model, and the actuarial data were analyzed using Cox model. RESULTS: A linear-quadratic model provided an alpha estimate of 0.339 (SE 0.115) and beta estimate of 0.067 (SE 0.027), which resulted in an alpha/beta ratio of 5.06 Gy (95% confidence interval -0.1 to 10.3). In all three schemes the overall radiation treatment time was short, which limits the rationales for incorporating time effect into the model. If, however, time was incorporated the alpha/beta ratio was 11.1 Gy and the dose increment required to compensate for repopulation was 0.15 Gy/day. The actuarial analysis provided similar alpha/beta estimates. CONCLUSION: Although because of the retrospective character of the study, nonrandomized selection of fractionation schedule, and uncontrolled quality of surgery the present results can be regarded as hypothesis generating only, the control rates obtained in the pelvis are consistent with a moderately low alpha/beta ratio for rectal cancer.

Delineation of Margins for the Planning Target Volume (PTV) for Image-Guided Radiotherapy (IGRT) of Gastric Cancer Based on Intrafraction Motion

Background: Application of the image-guided radiotherapy (IGRT) system for gastric cancer involving daily verification of patient positioning on the treatment machine allows minimisation of geometrical errors as a consequence of intra- and inter-fraction motion. The purpose of this study was to define the intrafraction motion in gastric cancer patients during a treatment session based on the IGRT system and designation of margins around the clinical target volume CTV (internal target volume ITV) necessary to delineate the planning target volume (PTV). Methods: Twenty gastric cancer patients were analysed. The total radiation dose for each was 45Gy in 25 fractions within 5 weeks. The margins for the PTV were calculated according to van Herk (2004), Stroom and Heijmen (2002) and the International Commission on Radiation Units and Measurements (ICRU) Report 62 formulas based on craniocaudal (Y axis), laterolateral (X axis) and anteroposterior (Z axis) shifts. Results: Delineated margins for the PTV in gastric cancer with the three formulas applied were respectively 0.2, 0.2, and 0.2cm in the lateral plane, 0.3, 0.3, and 0.3cm in the craniocaudal plane and 0.3, 0.3, and 0.2cm in the anteroposterior plane. Conclusions: Recommended margins for the PTV in gastric cancer calculated in this study based on intrafraction motion are 0.3cm, 0.2cm and 0.3cm in the craniocaudal, lateral and anterioposterior directions, respectively. Use of the IGRT system corrects for the motions between factions and allows reduction in ITV-PTV margins. The main advantage of the smaller margins in comparison to the non-IGRT radiotherapy is a reduction in the probability of radiation complications.

Cyberknife Radioablation of Prostate Cancer ­ Preliminary Results for 400 Patients

Objectives: To evaluate the tolerance and effectiveness of stereotactic ablative radiotherapy (SABR) applied in the treatment of low and intermediate risk (LR & IR) prostate cancer patients (PCP) and provide an evaluation of the level of risk group impact on treatment results. In addition, androgen deprivation therapy (ADT) usage and prostatic specific antigen (PSA) decline after SABR were assessed. Material and Methods: A total of 400 PCP (213 LR and 187 IR, including T2c) were irradiated with a CyberKnife using fd 7.25 Gy to TD 36.25 Gy. At the start of treatment, 60.3% of patients were undergoing ADT and this gradually decreased to 0% after 38 months. Follow-up was for a median of 15.0 months. Patients were monitored on SABR completion and 1, 4, 8 months later and then subsequently every 6 months. GI (Gastro-Intestinal) and GU (Genito-Urinary) acute and late adverse effects, PSA and ADT usage were evaluated. Results: Failure was noted in 9 patients (2.25%) (5 in LR and 4 in IR groups) - 4 relapses and 5 nodal metastases. No G3/4 late adverse effects (EORTC/RTOG) were observed. Some 0.5% of G3 GU and 0.3% of G3 GI acute reactions were noted respectively on the SABR completion day and one month later. The median of PSA declined 1.5 ng/ml during the first month and 0.6 ng/ml during the next three months. No impact of risk groups on treatment results was found. An impact of ADT on PSA decline was only confirmed for time point interactions. Conclusions: SABR for LR and IR PCP is a safe and effective treatment. The inclusion of T2c patients and the low percentage of IR patient failure permit us the assumption that this procedure could be utilized in the treatment of more advanced cases. The results do not allow clear definition of the impact of ADT on radioablation results in LR and IR+ T2c cases.

Protection of organs at risk during neoadjuvant chemoradiotherapy for gastric cancer based on a comparison between conformal and intensity-modulated radiation therapy.

The aim of the present study was to compare the techniques of dynamic intensity-modulated radiation therapy (IMRT) and three-dimensional conformal radiotherapy (3DCRT) in patients with gastric cancer. Implementation of the IMRT technique does not significantly affect the minimum and maximum dose levels in the planning target volume (PTV), but more effectively protects the critical organs. The study group consisted of 25 patients. The results of the analysis of the conformity index (CI) and the homogeneity index (HI) showed that the doses in the PTV regions were at a comparable level. The CI for the PTV was 0.95 for the 2-field technique, 0.95 for the 3-field technique, 0.96 for the 4-field technique and 0.94 for the IMRT technique. The CIs for these techniques for the clinical target volume (CTV) were 0.96, 0.96, 0.97 and 0.96, respectively, and the CIs for the gross tumor volume (GTV) were 0.99, 0.99, 0.99 and 0.98, respectively. The HI values for the PTV were 1.12 for the 2-field technique, 1.12 for the 3-field technique, 1.09 for the 4-field technique and 1.09 for the IMRT technique, and the HI values for the CTV were 1.12, 1.12, 1.09 and 1.08 for the same techniques, respectively. The HI values for the GTV were 1.09, 1.09, 1.07 and 1.06, respectively, which indicated significantly superior performance in the regions of healthy tissue. Statistical study was based on Friedman's rank analysis of variance to determine the level of reliability of the tested groups of variables (P<0.001). The present study demonstrated that the IMRT technique in the pre-operative radiotherapy of gastric cancer patients results in superior treatment tolerance and reduces the risk of damage to healthy tissue that is in close proximity to the irradiated area.

CyberKnife-based prostate cancer patient radioablation - early results of irradiation in 200 patients.

INTRODUCTION: Prostrate cancer (PC) is one of the most common malignancies and is frequently treated with an 8-week course of radiotherapy. CyberKnife (CK) based radioablation enables completion of therapy within 5-9 days. The aim of this study is an evaluation of the effectiveness and tolerance of CyberKnife-based radioablation in prostate cancer patients. MATERIAL AND METHODS: 200 PC patients (94 low risk [LR], 106 intermediate risk [IR]) underwent CK irradiation every other day (fraction dose [fd] 7.25 Gy, total dose [TD] 36.25 Gy, time 9 days). PSA varied from 1.1 to 19.5 (median 7.7) and T stage from T1c to T2c. The percentage of patients with Androgen Deprivation Therapy (ADT), GI (gastrointestinal) and GU (genitourinary) toxicity (EORTC/RTOG scale), and PSA were checked at 1, 4 and 8 months, and thereafter every 6 months - up to a total of 26 months - post-treatment. RESULTS: The percentage of patients without ADT increased from 47.5% to 94.1% after 26 months. The maximum percentage of acute G3 adverse effects was 0.6% for GI, 1% for GU and G2 - 2.1% for GI and 8.5% for GU. No late G3 toxicity was observed. The maximum percentage of late G2 toxicity was 0.7% for GI and 3.4% for GU. Median PSA decreased from 7.7 to 0.1 ng/ml during FU. One patient relapsed and was treated with salvage brachytherapy. CONCLUSIONS: We conclude that CK-based radioablation in low and intermediate risk PC patients is an effective treatment modality enabling OTT reduction and presents a very low percentage of adverse effects.

Radiotherapy and chemoradiotherapy as a novel option for the treatment of locally advanced inoperable gastric adenocarcinoma: A phase II study.

This phase II trial aimed to evaluate the tolerance and efficacy of radical radiotherapy or chemoradiotherapy in patients with primarily inoperable gastric cancer. The analysis was based on 13 patients with primarily inoperable gastric cancer. A total of 6 (46.2%) patients refused surgery and 7 (53.8%) had contraindications to anesthesia due to cardiological or respiratory reasons (4 and 3 patients, respectively). The treatment regimen consisted of radiotherapy and chemotherapy based on 5-fluorouracil. Half of the patients were not qualified to receive chemotherapy due to the presence of comorbidities. A total dose of 45 Gy was administered in 25 fractions. Of the 13 patients who started treatment, 12 (92.3%) completed radiotherapy. Local treatment response was observed in 6/12 patients (50%), with 5/12 (41.7%) displaying clinical complete response and 1/12 (8.3%) partial response. The 1- and 3-year overall survival rates and the median survival were 59 and 48% and 17.1 months, respectively. In conclusion, radical radiotherapy, either alone or in combination with chemotherapy, is safe for patients with inoperable locally advanced gastric cancer and may prolong survival.

Primary duodenal follicular lymphoma: 6-years complete remission after combined radio-immunotherapy.

Primary gastrointestinal lymphoma (PGL) is known to account for 40% of all extranodal non-Hodgkin's lymphomas (NHLs) and between 4% to 12% of all NHLs. The small intestine is the site of presentation in 20-30% of cases, with the terminal ileum usually involved. Duodenal localizations have always been thought to be rare, but are presently growing in incidence. We herein report on a case of Stage IV primary duodenal FCL, located to the second portion of the duodenum with concomitant minimal bone marrow involvement. The patient was frontline approached with a conservative combined modality treatment consisting of 4 weekly infusions of the chimeric human-murine IgG1 mono-clonal antibody against the B-cell surface antigen CD-20, Rituximab (375 mg/m2) and consolidation 3D conformal external beam radiotherapy up to a total dose of 36 Gy given into 20 fractions to the involved duodenal portion. Six years after treatment has been completed, the patient is free from disease with no treatment-related toxicity.