Thoracic radiotherapy of limited-stage small cell lung cancer : current situation of dose fractionation / 中华放射肿瘤学杂志

Thoracic radiotherapy is a major treatment and dose fractionation remains controversial in limited-stage small cell lung cancer. Twice-daily (BID) radiotherapy, as a standard protocol established in prospective studies, is often replaced by other treatment strategies in clinical practice due to the occurrence of side effects and inconvenience. In addition, in inoperable stage Ⅰ small cell lung cancer with negative lymph nodes, stereotactic ablative radiotherapy (SABR) provides a new option for some elderly patients who are expected to be unable to tolerate long-term radiotherapy. The appropriate dose fractionation scheme can both ensure the therapeutic effects and reduce toxic effects. This article reviews the research of limited-stage small cell lung cancer about dose fractionation.

Lattice radiation therapy - its concept and impact in the immunomodulation cancer treatment era

SUMMARY Voluminous tumors represent a challenge in radiation oncology, particularly when surgical resection is not possible. Lattice radiotherapy (LTR) is a technique that may provide equivalent or superior clinical response in the management of large tumors while limiting toxicity to adjacent normal tissues. LRT can precisely deliver inhomogeneous high doses of radiation to different areas within the gross tumor volumes (GTV). The dosimetric characteristic of LTR is defined by the ratio of the valley dose (lower doses - cold spots) and the peak doses, also called vertex (higher doses - hot spots), or the valley-to-peak dose ratio. The valley-to-peak ratio thereby quantifies the degree of spatial fractionation. LRT delivers high doses of radiation without exceeding the tolerance of adjacent critical structures. Radiobiological experiments support the role of radiation-induced bystander effects, vascular alterations, and immunologic interactions in areas subject to low dose radiation. The technological advancements continue to expand in Radiation Oncology, bringing new safety opportunities of treatment for bulky lesions.

RESUMO Tumores volumosos representam um desafio para a radio-oncologia, em especial quando a ressecção cirúrgica não é possível. A radioterapia com técnica Latisse (LTR) pode gerar resposta clínica equivalente ou superior ao tratamento convencional de grandes tumores, limitando a toxicidade nos tecidos normais adjacentes. A LRT pode fornecer com precisão altas doses não homogêneas de radiação em diferentes áreas do volume tumoral (GTV). A característica dosimétrica da LTR é definida pela razão entre a dose na região do vale (doses mais baixas - pontos frios) e as doses de pico, também chamadas de vértice (doses mais altas - pontos quentes) ou a razão da dose vale/pico. Dessa forma, a razão vale/pico quantifica o grau de fracionamento espacial da entrega de dose. A LRT entrega, dessa forma, altas doses de radiação sem exceder a tolerância de estruturas críticas adjacentes. Experimentos radiobiológicos suportam o chamado "efeito espectador" induzido por radiação, o qual promove alterações vasculares e interações imunológicas, levando à resposta tumoral mesmo em áreas expostas a baixas doses de radiação. Os avanços tecnológicos continuam a se expandir na radio-oncologia, trazendo, por meio da LTR, uma nova oportunidade segura de tratamento para lesões volumosas.

Research progresses of stereotactic body radiotherapy in gynaecological cancers / 中华放射医学与防护杂志

Stereotactic body radiation therapy(SBRT) is a new technology developed in recent years.The advantage of the technique resides in its ability to provide a high dose to tumor but spare normal tissues to an extent.The use of SBRT in gynecological cancers mainly concentrated in local treatment of pelvic recurrence,para-aortic lymph node metastasis and oligometastatic disease.SBRT boosts to macroscopic recurrences and oligometastatic disease can provide local control and a possibility of long-term disease-free survival in carefully selected patients.However,patients who received SBRT following prior irradiation,despite its tight conformality,were still confronted with significant morbidity.SBRT can be used as an alternative treatment for locally advanced cervical cancer after external-beam radiation therapy in patients who are unsuitable for brachytherapy.

Tumor pathological response and downstaging of locally advanced rectal cancer after neoadjuvant chemoradiotherapy: comparison of two radiation dose schedules / 中华放射医学与防护杂志

Objective To assess the short-term efficacy and tolerability of different radiotherapy doses schedules as 46 Gy and 50 Gy for locally advanced rectal cancer patients undergoing neoadjuvant chemoradiotherapy.Methods All patients with locally advanced rectal cancer who had received neoadjuvant chemoradiotherapy between Aug 2010 and May 2015 were enrolled.This retrospective analysis was performed according to the radiotherapy dose grouping of 46 Gy and 50 Gy groups.Concurrent chemotherapy regimen was capecitabine-based and oxaliplatin was added only when young patients (＜ 75 years old) were in a good condition.Total mesorector excision was scheduled 6-8 weeks after concurrent chemoradiotherapy.Results Totally 213 patients were enrolled in our analysis,including 61 cases in 46 Gy group and 152 cases in 50 Gy group.There were 145 male and 68 female patients.There were 22 patients diagnosed clinically with T2,180 with T3,and 11 with T4.Tumor distance from the anal verge was ≤5,＞5 and ＜ 10 cm,or ≥10 cm in 82,115 and 16 patients,respectively.T downstaging was observed in 95 (44.6％) patients,pathologic complete response (PCR) was shown in 48 (22.5％) patients.In the 46 Gy and 50 Gy groups,the rate of PCR was 18.0％ vs.24.3％ (P ＞0.05).In addition,good response rate (TRG 3 + 4) was 67.2％ vs.75.0％ (P ＞ 0.05),and T downstaging rate was 39.3％ vs.46.7％ (P ＞0.05).Subgroup analysis for T3N2/T4 patients,the rate of PCR was 6.3％ vs.23.3％ (P＞0.05),good response rate (TRG 3 +4) was 50.0％ vs.72.1％ (P＞0.05),and T downstaging was 31.3％ vs.46.5％ (P ＞0.05).There was no significant difference in treatment-related toxicity between the two groups.Conclusions The two different radiation dose fractionation (50 Gy vs.46 Gy) had no impact on pathologic tumor regression and T downstaging for locally advanced rectal cancer.Nonetheless,a further long-term follow-up is warranted to confirm the preliminary study.

Efficacy of high-dose hypofractionated radiotherapy in elderly patients with stage Ⅳ pancreatic cancer / 临床肝胆病杂志

ObjectiveTo investigate the efficacy and toxic and adverse effects of high-dose hypofractionated radiotherapy in elderly patients with stage Ⅳ pancreatic cancer. MethodsThe clinical data of the patients with pancreatic cancer and distant metastasis who were admitted to our hospital from September 2011 to May 2015 were collected, and all the patients underwent high-dose hypofractionated helical tomotherapy. The data on efficacy and toxic and adverse effects were obtained through follow-up, and the evaluation of adverse effects was performed according to National Cancer Institute-Common Terminology Criteria for Adverse Events version 4.02. The Kaplan-Meier method was used for survival analysis. ResultsA total of 33 patients older than 65 years received the high-dose hypofractionated radiotherapy. Of all the patients, 30 received follow-up visits, and the follow-up rate was 91.0%. The median survival time was 9 months, the 1-year overall survival rate was 24.0%, and the rate of pain relief was 80.0% (20/25). The treatment outcome of pancreatic lesions could be evaluated in 17 patients, among whom 4 (23.5%) achieved partial remission, 12 (70.6%) achieved stable disease, and 1 (5.9%) experienced progression. As for toxic and adverse effects, the incidence rate of grade 3 hematologic toxicity was 6.7% (2/30), and no patients experienced grade ＞2 upper gastrointestinal reactions. ConclusionIn elderly patients with stage IV pancreatic cancer, high-dose hypofractionated radiotherapy has tolerable toxic and adverse effects and can relieve cancer pain and prolong survival time.

Dose fractionation of stereotactic body radiation therapy for locally advanced pancreatic cancer / 中华放射肿瘤学杂志

Stereotactic body radiation therapy ( SBRT ) for locally advanced pancreatic cancer ( LAPC) shows good signs of efficacy as measured by local control,which can also reduce toxicity. The dose fractionation in foreign countries have changed from conventional fractionation to single fraction and finally moderate hypofractionation. It is similar to that in China, with the dose fractionation changing from conventional fractionation to moderate hypofractionation. This review introduces the latest research results of dose fractionation of SBRT for LAPC.

Do Biliary Complications after Hypofractionated Radiation Therapy in Hepatocellular Carcinoma Matter? / Journal of the Korean Cancer Association, 대한암학회지

PURPOSE: The purpose of this study is to evaluate the efficacy of hypofractionated radiation therapy (RT) in the treatment of unresectable hepatocellular carcinoma (HCC) after failure of transarterial chemoembolization (TACE) or in cases of refractory HCC, and to investigate biliary complications after hypofractionated RT. MATERIALS AND METHODS: We retrospectively enrolled patients with unresectable, TACE-unresponsive, or refractory HCC treated with hypofractionated RT between July 2006 and December 2012. The perihilar region was defined as the 1-cm area surrounding the right, left, and the common hepatic duct, including the gallbladder and the cystic duct. Significant elevation of total bilirubin was defined as an increase of more than 3.0 mg/dL, and more than two times that of the previous level after completion of RT. RESULTS: Fifty patients received hypofractionated RT and 27 (54%) had a tumor located within the perihilar region. The median follow-up period was 24.7 months (range, 4.3 to 95.5 months). None of the patients developed classic radiation disease symptoms, but four patients (8%) showed significant elevation of total bilirubin within 1 year after RT. During follow-up, 12 patients (24%) developed radiologic biliary abnormalities, but only two patients had toxicities requiring intervention. Estimated local progression-free survival, progression-free survival, and overall survival of the patients at 3-year post-hypofractionated RT were 89.7%, 11.2%, and 57.4%, respectively. CONCLUSION: Biliary complications associated with a higher dose exposure of hypofractionated RT were minimal, even in the perihilar region. Hypofractionated RT provided excellent local control and may be a valuable option for treatment of unresectable cases of TACE-unresponsive or refractory HCC.

Radiation Therapy Alone in cT1-3N0 Non-small Cell Lung Cancer Patients Who Are Unfit for Surgical Resection or Stereotactic Radiation Therapy: Comparison of Risk-Adaptive Dose Schedules / Journal of the Korean Cancer Association, 대한암학회지

PURPOSE: High dose definitive radiation therapy (RT) alone is recommended to patients with cT1-3N0 non-small cell lung cancer, who are unfit for surgery or stereotactic RT. This study was conducted to evaluate the clinical outcomes and cost-effectiveness following RT alone using two different modest hypofractionation dose schemes. MATERIALS AND METHODS: Between 2001 and 2014, 124 patients underwent RT alone. From 2001 till 2010, 60 Gy in 20 fractions was delivered to 79 patients (group 1). Since 2011, 60 Gy in 20 fractions (group 2, 20 patients), and 60 Gy in 15 fractions (group 3, 25 patients) were selectively chosen depending on estimated risk of esophagitis. RESULTS: At follow-up of 16.7 months, 2-year rates of local control, progression-free survival, and overall survival were 62.6%, 39.1%, and 59.1%, respectively. Overall survival was significantly better in group 3 (p=0.002). In multivariate analyses, cT3 was the most powerful adverse factor affecting clinical outcomes. Incidence and severity of radiation pneumonitis were not different among groups, while no patients developed grade 2 esophagitis in group 3 (p=0.003). Under current Korean Health Insurance Policy, RT cost per person was 22.5% less in group 3 compared with others. CONCLUSION: The current study demonstrated that 60 Gy in 15 fractions instead of 60 Gy in 20 fractions resulted in comparable clinical outcomes with excellent safety, direct cost saving, and improved convenience to the patients with tumors located at ≥ 1.5 cm from the esophagus.

Preoperative chemoradiation for locally advanced rectal cancer: comparison of three radiation dose and fractionation schedules

PURPOSE: The standard radiation dose for patients with locally rectal cancer treated with preoperative chemoradiotherapy is 45-50 Gy in 25-28 fractions. We aimed to assess whether a difference exists within this dose fractionation range. MATERIALS AND METHODS: A retrospective analysis was performed to compare three dose fractionation schedules. Patients received 50 Gy in 25 fractions (group A), 50.4 Gy in 28 fractions (group B), or 45 Gy in 25 fractions (group C) to the whole pelvis, as well as concurrent 5-fluorouracil. Radical resection was scheduled for 8 weeks after concurrent chemoradiotherapy. RESULTS: Between September 2010 and August 2013, 175 patients were treated with preoperative chemoradiotherapy at our institution. Among those patients, 154 were eligible for analysis (55, 50, and 49 patients in groups A, B, and C, respectively). After the median follow-up period of 29 months (range, 5 to 48 months), no differences were found between the 3 groups regarding pathologic complete remission rate, tumor regression grade, treatment-related toxicity, 2-year locoregional recurrence-free survival, distant metastasis-free survival, disease-free survival, or overall survival. The circumferential resection margin width was a prognostic factor for 2-year locoregional recurrence-free survival, whereas ypN category was associated with distant metastasis-free survival, disease-free survival, and overall survival. High tumor regression grading score was correlated with 2-year distant metastasis-free survival and disease-free survival in univariate analysis. CONCLUSION: Three different radiation dose fractionation schedules, within the dose range recommended by the National Comprehensive Cancer Network, had no impact on pathologic tumor regression and early clinical outcome for locally advanced rectal cancer.

Radiocirurgia e radioterapia estereotática no tratamento de meningeomas sintomáticos do seio cavernoso / Radiosurgery and stereotactic radiotherapy in the treatment of symptomatic cavernous sinus meningiomas

Introdução: Radiocirurgia estereotática (RCE) e radioterapia estereotática fracionada (RCEF) são inovações modernas de procedimentos radioterápicos, de alta precisão que modelam o feixe de radiação para coincidir com o contorno da lesão, por meio de um sistema de imobilização exata do paciente ao aparelho, com definição do alvo através da fusão de imagens de RM, TC, Angiografia e PET/CT; em que pelas coordenadas de referência estereotática, determina-se que a dose de radiação de alta energia prescrita pelo médico seja depositada somente no volume-alvo, com preservação dos tecidos sadios, órgãos ou estruturas localizadas em suas adjacências. Meningeomas do seio cavernoso (MSCs) representam um problema especial porque podem evoluir comprimindo ou infiltrando estruturas neurovasculares presentes no seio cavernoso. Há evidências de que a RCE e a RCEF proporcionam controle satisfatório do crescimento dos meningeomas do seio cavernoso (MSCs) com efeitos adversos reduzidos. Objetivo: Avaliar resultados da avaliação clínica e da neuroimagem de doentes sintomáticos com MSCs tratados com RCEF ou RCE exclusivamente ou de modo adjuvante à neurocirurgia. Casuística e métodos: Estudo tipo coorte e retrospectivo sobre a avaliação de 89 doentes com MSC sintomático tratados com RCE (36%) ou RCEF (64%) entre janeiro de 1994 e março de 2009 e acompanhados até o final de 2012. Haviam sido submetidos à ressecação neurocirúrgica parcial (Simpson IV) ou à biopsia (Simpson V) previamente à radioterapia 29,2% dos doentes. A dose média de RCE foi de 14Gy, e a dose total de RCEF variou entre 50,4 e 54Gy, sendo fracionada em 1,8-2Gy/dose/dia. Resultados: O período de acompanhamento variou entre 36 e 180 meses (mediana de 73 meses). A percentagem de melhora dos sintomas neuroclínicos individuais e de melhora clínica e radiológica (p > 0,05) apresentou valores semelhantes nos doentes tratados com RCE ou RCEF, sendo respectivamente de 41,6% e 48,3%. Em 37% dos doentes, houve...

Introduction: Stereotactic radiosurgery (SRS) and fractionated stereotactic radiotherapy (FSRS) are modern innovations in radiotherapy procedures, precision shaping the radiation beam to match the contour of the lesion, through a system of accurate patient immobilization to the device, defining target through the fusion of MRI, CT, angiography and PET / CT, which is determined by reference to stereotactic coordinates. The radiation dose of high energy prescribed by the doctor to be delivery only in the target interest, with preservation of healthy tissues, organs or structures located in their vicinity. Cavernous sinus meningiomas (CSMs) pose a special problem because they can evolve compressing or infiltrating the neurovascular structures present of the cavernous sinus. There are evidences that SRS and FRS are efficient in the treatment of CSMs. Objectives: The evaluation of the long-term clinical results and neuroimaging findings in patients with symptomatic CSM treated with FSRT or SRS as single therapy or after a previous neurosurgical treatment. Patients and methods: Retrospective cohort study involving 89 patients with symptomatic CSMs treated with SRS (36%) or FSRS (64%) from January 1994 to March 2009, and followed until the end of 2012. Previous neurosurgical partial resection (Simpson IV) or biopsies (Simpson V) had been performed in 29.2% of the patients. The median dose of SRS was 14Gy and the total dose of FSRT ranged from 50.4 to 54Gy, fractionated in 1.8 to 2Gy/dose/day. Results: The follow-up period ranged from 36 to 180 months (median= 73months). There was improvement in the individual symptoms and in the clinical and radiological findings regardless the radiotherapeutic method in 41.6% and 48.3% of the patients treated with SRS or FSRT, respectively (p > 0,05). In 37% of the patients, at least one neurological complaint present before the treatment did not change and in 43.8% patients, the image of the tumor remained stable....

Study of two different dose fractionation schedules of post mastectomy chest wall irradiation in carcinoma breast patients.

Background: Breast cancer is the most frequently diagnosed cancer and the leading cause of cancer death in women. Aims & Objective: To compare two different dose fractionation schedules in terms of overall treatment, locoregional control, acute and late toxicities and patient compliance. Material and Methods: Patients of postmastectomy non metastatic breast cancer were randomized in two arms: Arm A (45) Arm B (46) according to dose fractionation schedule of external radiation given to chest wall and draining lymphatics. Arm A was given 50 Gy in 25 fractions and Arm B was given 40 Gy in 17 fractions. After completion of radiation patients were kept on follow up. Results: Median follow up was 20 months. In arm A & B the median overall treatment time was 40 and 27 days with respective ranges of 36-47 days and 22-33 days .The patients in both the arms tolerated radiation well, skin reactions were most common followed by nausea and vomiting .Grade II and III acute reactions were comparable in both arms. There was non-significant increase in both late skin and subcutaneous skin toxicities in arm B. Result of treatment of both arms are, chest wall failure 5% v/s 9% (p> 0.05), nodal failure 8% v/s 7% (p> 0.05) and distant metastasis 25% v/s 28% (p> 0.05). Conclusion: Both the studied dose fractionation schedules are equally efficacious in terms of locoregional control, acute and late toxicities. The shorter schedules in Arm B gives an added advantage of decreased overall treatment time giving better compliance and reduces work load of overburdened department.

Effects of preoperative irradiation using fractioned electron beam on the healing process of colocolonic anastomosis in rats undergoing early and late surgical intervention

PURPOSE: To investigate the effects of preoperative fractioned irradiation using an electron beam on the healing process of colocolonic anastomoses in rats that underwent early and late surgical intervention. METHODS: Thirty Wistar rats, distributed as follows: group A (surgery only), group B (fractionated irradiation for 30 days (if), surgery seven days after the end of it), group C (if for 30 days, and surgery after 30 days of termination). On the seventh postoperative day the anastomotic segment analysis was taken, using tension tests, histology and collagen deposition evaluation by computerized analysis. RESULTS: Regarding the tension resistance of the anastomosis, there were no statistical differences (p=0.42). However, a significant increase in cells number in the inflammatory infiltrate in the group with a longer interval between surgery and pre op radiation (p<0.05). The collagen concentration had no significant variance. CONCLUSION: The irradiation in divided doses increased local inflammatory cellularity when the surgery was performed later. This result did not affect the increase of complications, nor on the local concentration of collagen, achieving similar clinical outcomes.

Long-term results of late-course accelerated hyperfractionation radiotherapy for nasopharyngeal carcinoma / 中国肿瘤临床

Objective:This work aims to explore the long-term efficacy and complications of late-course accelerated hyperfrac-tionation (LCAHF) for treating nasopharyngeal carcinoma. Methods:A total of 58 patients who consulted from December 2005 to May 2008 and histologically proven nasopharyngeal carcinoma at initial diagnosis were randomized into an LCAHF group (experimental group) and a conventional fractionation (CF) group (control group). The treatment dose for both groups was 2 Gy per fraction once dai-ly, 5 days a week. After the 40 Gy to 50 Gy dose, the dosage in the LCAHF group was increased to two daily doses at 1.5 Gy per frac-tion 6 h apart, 5 days a week. The total dose in this group was 73 Gy to 76 Gy, the total dose in the CF group was 70 Gy to 76 Gy, with the total course of the treatment shortened by 0.5 weeks to 1.5 weeks in the former group. Results:The 5-year control rates of the naso-pharyngeal cancers was 86% in the LCAHF group and 59% in the CF group (P=0.021), with statistically significant differences be-tween the two groups. The late complications slightly increased in the LCAHF group than in the CF group, but the differences were not statistically significant. Conclusion:LCAHF treatment improves the local control of nasopharyngeal carcinoma without increasing the incidence of long-term complications.

Hypofractionated radiotherapy for non-small-cell lung cancer / 国际肿瘤学杂志

Hypofractionated three-dimensional confornul radiotherapy (3DCRT) makes it possible to further improve loeal control,overall survival and the quality of life for the patients with non-small-cell lung cancer (NSCLC).But the dose-fractionation and total dose are not yet clear,which need further study.Hypofractionated stereotactic body radiotherapy (SBRT) for early-stage NSCLC patients is well tolerated and results in excellent local control and overall survival.SBRT is expected to become a new standard treatment in patients with early stage NSCLC.

Definitive Radiation Therapy for Early Glottic Cancer: Experience of Two Fractionation Schedules

OBJECTIVES: The authors would report the results of definitive radiation therapy (RT) for early glottic cancer by two different radiation dose schedules. METHODS: From February of 1995 till June of 2008, 157 patients with T1-2N0 glottic cancer were treated with curative RT at Samsung Medical Center. All patients had squamous cell carcinoma, and there were 89 patients (56.7%) with T1a, 36 (22.9%) with T1b, and 32 (20.4%) with T2. Two different radiation dose schedules were used: 70 Gy in 35 fractions to 64 patients (40.8%, group A); and 67.5 Gy in 30 fractions to 93 patients (59.2%, group B). The median treatment durations were 50 days (range, 44 to 59 days) and 44 days (range, 40 to 67 days) in the groups A and B, respectively. RESULTS: The median follow-up durations were 85 and 45 months for the groups A and B. No severe late complication of RTOG grade 3 or higher was observed, and there was no difference in acute or chronic complication between the groups. Twenty-four patients experienced treatment failure: local recurrence only in 19 patients; regional recurrence only in one; combined local and regional recurrence in four; and systemic metastasis in none. The overall 5-year disease-free survival and disease-specific survival rates were 84.7% and 94.8%. The disease-free survival rate in the group B was better (78.3% vs. 90.8%, P=0.031). This difference was significant only in T1 stage (83.4% vs. 94.6%, P=0.025), but not in T2 (62.7% vs. 60.6%, P=0.965). Univariate analysis showed that the tumor extent, cord mobility, T-stage, and the dose schedule had significant influence on the disease-free survival, and multivariate analysis showed that only the tumor extent and the dose schedule were associated with the disease-free survival. CONCLUSION: Superior disease-free survival could be achieved by 2.25 Gy per fraction without increased toxicity over shorter RT duration, when compared with 2.0 Gy per fraction.

Câncer de mama estádio inicial e radioterapia: atualização / Early stage breast cancer and radiotherapy: update

O câncer de mama é a neoplasia maligna mais frequente entre as mulheres. A escolha terapêutica depende do estádio clínico da doença, das características anatomopatológicas, idade, entre outros. O objetivo do presente estudo é apresentar uma atualização dos conceitos e definições da radioterapia (RT) no tratamento conservador do câncer de mama estádio inicial, enfatizando as indicações, contraindicações, dose e fracionamento da RT (esquema clássico, hipofracionado e irradiação parcial da mama), RT adjuvante no carcinoma ductal in situ (CDIS), irradiação das cadeias linfonodais e relação da RT com preditores moleculares de recorrência. Foram utilizadas as bases de dados MEDLINE, SciELO e Cochrane para a seleção dos principais artigos disponíveis sobre a temática proposta. A RT adjuvante tem um papel definido na abordagem das pacientes com câncer da mama submetidas à terapia cirúrgica conservadora. Em pacientes selecionadas, podem-se empregar esquemas de RT hipofracionada ou irradiação parcial das mamas. Todas as pacientes com CDIS devem receber RT adjuvante. Não se sabe a correlação do papel da RT com preditores moleculares de recorrência local e sistêmica.

Breast cancer (BC) is the most common malignancy among women. Therapeutic options are based on disease staging, histopathological characteristics, age, and others. The objective of the present study is to carry out an update of the concepts and definitions of radiotherapy (RT) in conservative treatment of early-stage breast cancer, with emphasis on indications, contraindications, RT dose fractionation schedules (classic, hypofractionated and partial breast irradiation), adjuvant RT in ductal carcinoma in situ (DCIS) and molecular predictors of recurrence. MEDLINE, SciELO and Cochrane databases were used for article selection. Adjuvant RT is indicated for patients with BC who underwent conservative breast surgery. In selected patients, hypofractionated or partial breast irradiation can be used. Adjuvant RT should be provided for all patients with DCIS. The correlation of RT and molecular predictors of local and systemic recurrence are not yet well-known.

The effect of dose fractionation on overall survival in patients with limited-stage small cell lung cancer / 中华放射肿瘤学杂志

Objective To study the effect of different dose fractionation on overall survival in patients with limited-stage small cell lung cancer (LS-SCLC). Methods LS-SCLC patients treated with radical combined chemotherapy and radiotherapy (RT) between January 2001 and Dec 2007 were analyzed retrospectively. According to the dose fractionation schemes, patients were divided into three groups:conventional fractionated RT (1. 8 -2.0 Gy,once daily), hyperfractionated RT (1.4 Gy, twice daily) and hypofractionated RT (2. 5 Gy,once daily). Overall survival, disease free survival and pattern of failures of the three groups were compared. A total of 177 patients were enrolled, including 63 patients in conventional fractionated RT group, 79 in hyperfractionated RT group and 35 in hypofractionated RT group. Results The overall follow-up rate was 96. 6%. The patient numbers with follow-up of more than 2 and 5 years were 153 and 92, respectively. The median survival time of the entire group was 22. 4 months, and the 2-and 5-year survival rates were 43.4% and 23. 5%, respectively. The 2-year survival rates for three groups were 31%, 46% and 59% (x2 =7.94,P=0.019), respectively. The 2-year disease free survival for three groups were 20%, 31% and 40% ( x2 = 4. 86, P = 0. 088 ), respectively. In the pairwise comparisons,patients in hypofractionated RT group have better survival than those in conventional fractionated RT group ( x2 = 7. 81, P = 0. 005 ), the effect of hyperfractionated RT group lies between the hypo-and the conventional fractionated RT groups, but no significant differences were detected ( x2 = 2. 31, P = 0. 128; x2 = 2. 95, P =0. 086). The mildest side effect was found in the hypofractionated RT group. No statistically significant differences were found in the patterns of first failure. Conclusion The hypofractionated RT scheme showed potential survival benefits for patients with LS-SCLC and should be considered in the setting of randomized clinical trials.

Uncertainty of target volume and organ at risk during fractional radiotherapy / 国际肿瘤学杂志

Anatomic structures and their relative position of the target and organs at risk surrounded will change more or less during fractional radiotherapy.These uncertainties will affect the practice of treatment planning correctly.The degree of these uncertainties can be investigated by imaging verification system during clinical practice.The possible reasons of these uncertainties may be tumor volume variations,organ motions orshape changes,patients weight or form changes and set-up errors.The development and practice of imageguided radiotherapy,dose guided radiotherapy and adaptive radiotherapy can offer rational approaches to over-come the uncertainties of the target and organ at risk surrounded during radiotherapy.

Clinical study of whole course accelerated fractionation radiotherapy for 126 patients with esophageal carcinoma / 肿瘤研究与临床

Objective To evaluate the therapeutic effects of whole course hyperfractionation radiotherapy for esophageal carcinoma. Methods Form January 2000 to December 2001,126 patients with esophageal carcinoma were treated by whole course hyperfractionation radiotherapy(120～140 cGy per fraction, 2 times per day, to a total dose of 6400～7400 cGy) in our department. Results The short-term effective rate was 99.21%. The 1, 2 and 5 year survival rate was 61.11%, 41.27%, 23.02% and the median survival time was 1.29 years. The 1, 2 and 5 year disease-free survival rates was 57.94%, 38.10%, 19.84% and the median disease-free survival time was 1.16 years. Conclusion It is promising of whole course hyperfractionation radiotherapy for esophageal carcinoma. But it must be validated by the large-scale clinical trials.

Late course accelerated hyperfractionation radiotherapy for nasopharyngeal carcinoma / 中华放射肿瘤学杂志

Objective To study the efficacy of late course accelerated fractionation(LCAF) radio- therapy in the treatment of nasopharyngeal carcinoma(NPC).The end-po s were local control,radiation-in- duced complications,factors influencing survival.Methods From December 1995 to April 1998,178 NPC patients were admitted for radiation treatment.The radiation beam used was ~(60)Co?or 6 MV X-ray.For the first two-thirds of the treatment,two daily fractions of 1.2 Gy were given to the primary lesion ,with an interval of≥6 hours,5 days per week to a total dose of 48 Gy/40 fractions,over a period of 4 weeks.For the last one third of the treatment,i.e.beginning from the 5th week,an accelerated hyperfractionation schedule was carried out.The dose per fraction was increased to 1.5 Gy,2 fractions per day with an interval of≥6 hours,the total dose for this part of the protocol was 30 Gy/20 fractions over 2 weeks.Thus the total dose was 78 Gy in 60 fractions in 6 weeks.Results All patients completed the treatment.Acute mucosi- tis:none in 2 patients,Grade 1 in 43,Grade 2 in 78,Grade 3 in 52,and Grade 4 in 3 patients.Local control rate:the 5-year nasopharyngeal local control rate was 87.7%,and the cervical lymph node local control rate was 85.7%.The 5-year distant metastasis rate was 26.1%,and 5-year survivals was 67.9%. Sixteen patients had radiation-induced cranial nerve palsy.Conclusions With this treatment schedule, patient's tolerance is good,local control and 5 year survivals are better than control groups of conventional fractionation and hyperfractionation radiotherapy.Radiation-related late complication does not increase.Ran- domized clinical trials are being carried out to further confirm the efficacy of LCAF for nasopharyngeal carci- noma.