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Objective:To investigate the feasibility of surface-guided hypo-fractionated radiotherapy for intracranial metastasis with open face mask immobilization.Methods:Nineteen patients treated with hypo- fractionated radiotherapy for intracranial metastasis in our hospital were included. Before the start of treatment, each patient underwent simulation with open face mask immobilization. During the treatment, cone-beam CT(CBCT)images were collected for verification each time. Laser-guided positioning was used for the first time in the treatment, and surface images were captured after six-dimensional position correction as the reference images for subsequent treatment. Subsequent treatment was randomly divided into laser-guided positioning group(LG, 85/F)and optical surface-guided positioning group(SG, 101/F). The six-dimensional error data of patients with two positioning methods were compared and expressed as mean ± standard deviation. Meanwhile, the correlation and consistency between the optical surface error data and the gold standard CBCT error data were compared in the laser-guided fraction. GraphPad Prism 6.0 software was used for data processing and mapping, and SPSS 21.software was used for mean analysis and normality test. Pearson correlation analysis was used to analyze the correlation, and Bland-Altman plot analysis was used to test the coincidence between two methods.Results:Compared with the laser-guided positioning, the 3D error of optical surface-guided positioning was reduced from(0.35±0.16)cm to(0.14±0.07)cm. The Pearson coefficient of correlation along all three directions was less than 0.01,R 2 was 0.91,0.70 and 0.78 on Lat, Lng and Vrt, and R 2 was 0.75,0.85 and 0.77 on Pitch, Roll and Rtn(all P<0.01), respectively. The measurement results of two methods were positively correlated. The Bland-Altman plot analysis showed that the 95% limits of agreement were within preset 3 mm tolerance([-0.29 cm, 0.19 cm], [-0.25 cm, 0.25 cm], [-0.27 cm, 0.19 cm]), and the 95% limits of agreement were within preset 3° tolerance(Pitch[-1.76°,1.76°], Roll[-1.54°,1.60°], ROT[-2.18°,1.69°]), indicating agreement between two methods. Conclusions:The optical surface-guided positioning can reduce the setup errors in the hypo-fractionated radiotherapy for intracranial metastasis with open face mask immobilization. The optical surface error and CBCT error have good correlation and agreement.
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Objective To compare the toxicity between different dose fractionation regimens in postoperative radiotherapy for prostate cancer. Methods Patients with prostate cancer who received postoperative radiotherapy with moderate hypo-fractionation ( 62. 75 Gy in 25 fractions, 2. 51 Gy per fraction) or conventional fractionation (72 Gy in 36 fractions, 2 Gy per fractions) in our hospital from 2011 to 2017 were enrolled as subjects.All patients received intensity-modulated radiotherapy and daily cone-beam computed tomography image-guided radiotherapy. According to the propensity score matching ( PSM ) method, 35 patients treated with moderately hypo-fractionated radiotherapy were matched to 35 patients treated with conventionally fractionated radiotherapy based on age, irradiated volume, hormonal therapy, interval between surgery and radiotherapy, and comorbidities ( diabetes and hypertension). Toxicity was evaluated according to Radiation Therapy Oncology Group criteria. Comparison was made by the Fisher's exact probability test. Results One hundred and thirteen patients, consisting of forty-one in moderate hypo-fractionation group and seventy-two in conventional fractionation group, were enrolled as subjects. The median follow-up time in the two groups was 5. 6 and 45. 0 months, respectively. There were no significant differences in incidence rates of grade 2 acute gastrointestinal (GI) or genitourinary (GU) toxicity between the two groups ( 7% vs. 7%, P＝ 1. 000; 15% vs. 17%, P＝ 0. 847). After PSM, there were still no significant differences in incidence rates of grade 2 acute GI or GU toxicity between the two groups (9% vs. 11%, P＝0. 814; 14% vs. 11%, P＝ 0. 670). None of patients reported ≥grade 3 GI or GU toxicity. Conclusions Preliminary results show that moderate hypo-fractionation, compared with conventional fractionation, does not increase the risk of acute GI or GU toxicity in patients undergoing postoperative radiotherapy for prostate cancer.
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Objective To assess the acute toxicity of a hypo-fractionated regimen of intensity-modulated radiotherapy to the prostatic bed after prostatectomy.Methods From February to August 2017,twenty cases with prostate adenocarcinoma after prostatectomy were recruited.The prescribed dose to the whole pelvis and the prostatic bed was 45 Gy delivered in 1.8 Gy per fraction and 62.75 Gy delivered in 2.51 Gy per fraction,respectively.Acute toxicity was recorded and graded according to Radiation Therapy Oncology Group (RTOG) criteria and Common Terminology Criteria for Adverse Events (CTCAE) 4.0.Results The median follow-up was 7.5 months.Grade 2 acute genitourinary and gastrointestinal toxicity was observed respectively in two cases (10％) and one (5％),respectively.Two cases (10％) complained of grade 2 urinary incontinence during radiation therapy,but recovered to grade 0 or grade 1 after the first month of follow-up.Conclusions After prostatectomy,moderately hypo-fractionated radiotherapy (2.51 Gy × 25) compared with conventional fractionated radiotherapy previously reported did not increase the risk of acute toxicity.The incidence of urinary incontinence did not increase during short-term of follow-up.
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BACKGROUND: Surgery is the standard of care for early stage (T1-2, N0, M0) non-small cell lung cancer. A considerable number of these patients are ineligible for surgery due to age and comorbidities. Hypo fractionated high-dose stereotactic body radiotherapy (SBRT) is being performed for these group of patients. There is paucity of literature regarding this novel technique from the Indian subcontinent. AIMS AND OBJECTIVES: We hereby report the dosimetry, response and outcome of our small cohort of early stage non-small cell lung cancer patients treated with SBRT. MATERIALS AND METHODS: Between December 2007 and December 2010, 8 patients of early stage (T1-2N0M0) underwent SBRT at our centre. All the patients had undergone whole body PET-CT scan, MRI brain and pulmonary function test (PFT with DLCO). The SBRT schedules included 48 Gy in 6 fractions for peripherally located and 48 Gy in 8 fractions for centrally located tumors. Response and toxicity were assessed in 3 monthly follow up visits. RESULTS: The median duration of follow up was 18 months (range 8-44 months). The median age of the patients was 70 years (range 63-82 years) and the median tumor diameter was 4 cm (range 2.8-5.0 cm). The mean PTV volume was 165 cc(range 127.3- 193.9 cc). The mean dose to the PTV was 99.5% (range 97.7- 102.1%). After 3 months, 7 patients had complete metabolic response and 1 patient had partial metabolic response. Overall survival at 1.5 years was 87.5%. One patient had grade 2 pneumonitis. No toxicities of grade 3 or higher were identified. CONCLUSION: SBRT for early stage NSCLC resulted in excellent local control with minimal toxicity and can be considered as a treatment option in properly selected patients.
Subject(s)
Aged , Aged, 80 and over , Carcinoma, Non-Small-Cell Lung/pathology , Carcinoma, Non-Small-Cell Lung/surgery , Female , Humans , Lung Neoplasms/pathology , Lung Neoplasms/surgery , Male , Middle Aged , Neoplasm Staging , Radiosurgery/methods , Treatment OutcomeABSTRACT
Resultados preliminares del tratamiento con radioterapia hipofraccionada, en pacientes con cáncer de mama en estadio precoz, y cirugía preservadora. Análisis retrospectivo de 64 pacientes estadios 0, I y II, ganglios negativos, tratadas entre marzo 2009 abril 2011. Tratamiento con planificación conformada tridimensional, dosis de 42,6 Gy en 16 fracciones de 2,66 Gy a toda la mama, más dosis adicional de 7,98 Gy en 3 fracciones al lecho del tumor primario. La distribución por estadios fue: estadio 0 15/ 64 pacientes 23,4%; estadio I 41/64 64,1%, estadio II 8/64 12,6%. Seguimiento de 1 a 2,3 meses, promedio 4,4 meses. Todas las pacientes se encuentran vivas, libres de enfermedad hasta el momento. Complicaciones agudas: 85,94 radiodermatitis grado 0-I (55/64), 7,81% radiodermatitis grado II (5/64),3,1% grado III (2/64) y 2 pacientes no fueron evaluables, 6-24 meses después de finalizar la irradiación, 53,1% no presentó complicaciones, 32,8% (21/64) presentaron radiodermatitis grado I (eritema, hiperpigmentación), 1,6% (1) dermatitis grado II, 2 pacientes dermatitis grado III,6/64 (9,3%). 3 estudios aleatorios han demostrado la efectividad de los regímenes de hipofraccionamiento, resultados comparables a los esquemas de fraccionamiento convencional. Los resultados preliminares, nos animan a continuar el empleo de estos esquemas de radioterapia en la práctica clínica. Es necesario un mayor tiempo de seguimiento en la serie de pacientes presentadas, para evaluar los resultados de control local, sobrevida y morbilidad tardía por radioterapia
Preliminary results obtained with hypo fractionated radiotherapy in patients with early breast cancer who have undergone breast conserving surgery. Retrospective analysis 64 patients treated from March 2009- April 2011. Treated with 3D conformal radiation therapy; dose 42.6 Gy in 16 fractions 2.66 Gy was given to the breast followed by a boost to tumor bed of 7.98 Gy in 3 fractions. Distribution according to stage was: Stage 0 15/64 patients 23.4%; stage I 41/64 64.1% and stage II 8/64 12.6%. Mean follow up 4, 4 months, with range 1 to 2.3 months. All patients are alive and free of disease, at moment analysis the data. Acute complications: Grade 0-1 skin reactions 85.94% (55/64 ), grade II 7.81% (5/64 ), grade III 3,1% (2/64), 2 patients could not be evaluated. 6-24 months after completion treatment 53,1% had no complications; 32.8% (21/64) grade I dermatitis (Erythema, hyper pigmentation); 1.6% (1) grade II, 2 patients grade III dermatitis, 6/64 patients (9.3%) there was mild subcutaneous fibrosis. 3 randomized clinical trials, regimens of hypo fraction y have produced results comparable to conventional fractionation. The preliminary results of this study are encouraging; we continue to apply this regimen in the clinical practice. Obviously a longer follow up time is necessary to determine results regarding survival, local control and chronic complications of radiotherapy in the present study