62 Multi-institutional药理药效研究 动物模型

PII S0360-3016(99)00253-9

CLINICAL INVESTIGATION Esophagus

MULTI-INSTITUTIONAL RANDOMIZED TRIAL OF EXTERNAL

RADIOTHERAPY WITH AND WITHOUT INTRALUMINAL BRACHYTHERAPY

FOR ESOPHAGEAL CANCER IN JAPAN T OMOHIKO O KAWA ,M.D.,*T AKUSHI D OKIYA ,M.D.,†M ASAMICHI N ISHIO ,M.D.,‡

Y OSHIO

H ISHIKAWA ,M.D.,§K OZO M ORITA ,M.D.,࿣AND J APANESE S OCIETY OF T HERAPEUTIC R ADIOLOGY

AND O NCOLOGY (JASTRO)S TUDY G ROUP

*Department of Radiology and Oncology,Tokyo Women’s Medical University,Tokyo,Japan;†Department of Radiology,Tokyo Medical Center,Tokyo,Japan;‡Department of Radiology,Sapporo National Hospital,Hokkaido,Japan;§Health and Welfare

Department,Hyogo Prefectural Government,Hyogo,Japan;and ࿣Department of Radiation Oncology,Aichi Cancer Center,Aichi,Japan

Purpose:With the aim of improving the results of treatment of esophageal cancer,we designed this multi-institutional,randomized trial to establish the optimal irradiation method in radical radiation therapy for esophageal cancer by clinically evaluating external irradiation alone and in combination with intraluminal brachytherapy.

Methods and Materials:The study population consisted of patients with squamous cell carcinoma who were expected to be successfully treated with radical radiation therapy.The patients who could be given intraluminal brachytherapy at the end of external irradiation of 60Gy were stratified into 2groups.Patients assigned to receive external irradiation alone received boost irradiation of 10Gy/week on a schedule similar to the previous one,and with the same or smaller irradiation field.Intraluminal brachytherapy was performed,as a rule,with the reference dose point set at a depth of 5mm of the esophageal submucosa,and a total of 10Gy was irradiated at a daily dose of 5Gy,on a once-weekly schedule with low-dose-rate or high-dose-rate brachytherapy equipment.

Results:A total of 103patients were registered,94of whom were analyzable,with 8ineligible,and 1for whom complete information was unavailable.The overall cumulative survival rate was 20.3%at 5years.The cause-specific survival rate was 31.8%at 5years.The cause-specific survival rate at 5years was 27%in the external irradiation alone group and 38%in intraluminal brachytherapy combined group.There was no significant difference between the 2groups (p ؍0.385).However,in the patients with 5cm or less tumor length,the cause-specific survival rate was 64%at 5years in the intraluminal brachytherapy combined group,which showed a significant improvement over 31.5%in the external irradiation alone group (p ؍0.025).In the patients with Stage T1and T2disease,cause-specific survival rates tended to be better in the intraluminal brachytherapy combined group than in the external irradiation alone group (p ؍0.088).In the patients with more than 5cm tumor length or Stage T3–4disease,there were no significant differences between the two groups by treatment methods (p ؍0.290).The incidence of early and late complications did not differ according to whether intraluminal brachytherapy was used.

Conclusion:For the purpose of establishing the usefulness of intraluminal brachytherapy,further prospective randomized studies are necessary to evaluate the efficacy in tumors with short length and those with shallow invasion,or to assess the usefulness of intraluminal brachytherapy,as additional irradiation in large advanced tumors have been shown to have disappeared by diagnostic imaging after chemoradiotherapy with 60Gy/6w external irradiation.©1999Elsevier Science Inc.

Esophageal cancer,Radiotherapy,Intraluminal Brachytherapy.

INTRODUCTION

To improve the results of treatment of patients with esoph-ageal cancer,it is important to achieve good local control.Because the esophagus is adjacent to highly radiation-sen-sitive organs such as the lungs,bone marrow,etc.,it is difficult to irradiate tumors with high doses.Although irra-diation techniques have improved as a result of advances in treatment planning equipment and irradiation equipment,there are still some patients in whom radical radiation therapy within doses that the bone marrow and lung can tolerate is difficult with external irradiation alone.On the other hand,intraluminal brachytherapy allows high-dose irradiation of esophageal cancer,with little exposure of

Reprint requests to:Tomohiko Okawa,M.D.,Department of Radiology and Oncology,Tokyo Women’s Medical University,8-1Kwada-cho,Shinjuku Ku Tokyo,162-8666,Japan.Tel:03-3353-8111;Fax:035269-7355.

Acknowledgments —We wish to express our sincere thanks to the medical institutions and physicians who kindly contributed to this investigation by registering cases and recording case report forms.Accepted for

publication 28April 1999.

Int.J.Radiation Oncology Biol.Phys.,Vol.45,No.3,pp.623–628,1999

Copyright ©1999Elsevier Science Inc.Printed in the USA.All rights reserved

0360-3016/99/$–see front matter

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