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.

Prognostic value and clinical correlations of 18-fluorodeoxyglucose metabolism quantifiers in gastric cancer.

AIM: To investigate the correlations of pre-treatment positron emission tomography-computer tomography (PET-CT) metabolic quantifiers with clinical data of unstratified gastric cancer (GC) patients. METHODS: Forty PET-CT scans utilising 18-fluorodeoxyglucose in patients who received no prior treatment were analysed. Analysis involved measurements of maximum and mean standardised uptake volumes (SUV), coefficient of variation (COV), metabolic tumour volumes and total lesion glycolysis of different thresholds above which the tumor volumes were identified. The threshold values were: SUV absolute value of 2.5, 30% of SUVmax, 40% of SUVmax, and liver uptake-based (marked 2.5, 30, 40 and liv, respectively). Clinical variables such as age, sex, clinical stage, performance index, weight loss, tumor histological type and grade, and CEA and CA19.9 levels were included in survival analysis. Patients received various treatment modalities appropriate to their disease stage and the outcome was defined by time to metastasis (TTM) and overall survival (OS). Clinical and metabolic parameters were evaluated by analysis of variance, receiver operating characteristics, univariate Kaplan-Meier, and multivariate Cox models. P < 0.05 was considered statistically significant. RESULTS: Significant differences were observed between initially disseminated and non-disseminated patients in mean SUV (6.05 vs 4.13, P = 0.008), TLG2.5 (802 cm(3) vs 226 cm(3); P = 0.031), and TLG30 (436 cm(3) vs 247 cm(3), P = 0.018). Higher COV was associated with poor tumour differentiation (0.47 for G3 vs 0.28 for G1 and G2; P = 0.03). MTV2.5 was positively correlated to patient weight loss (< 5%, 5%-10% and > 10%: 40.4 cm(3) vs 123.6 cm(3) vs 181.8 cm(3), respectively, P = 0.003). In multivariate Cox analysis, TLG30 was prognostic for OS (HR = 1.001, 95%CI: 1.0009-1.0017; P = 0.047) for the whole group of patients. In the same model yet only including patients without initial disease dissemination TLG30 (HR = 1.009, 95%CI: 1.003-1.014; P = 0.004) and MTV2.5 (HR = 1.02, 95%CI: 1.002-1.036; P = 0.025) were prognostic for OS; for TTM TLG30 was the only significant prognostic variable (HR = 1.006, 95%CI: 1.001-1.012; P = 0.02). CONCLUSION: PET-CT in GC may represent a valuable diagnostic and prognostic tool that requires further evaluation in highly standardised environments such as randomised clinical trials.

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.