I N V E S T I G A T I O N O F A N A C C I D E N T A L E X P O S U R E O F R A D I O T H E R A P Y PA T I E N T S I N PA N A M A Report of a Team of Experts, 26 May–1 June 2001 I N T E R N A T I O N A L A T O M I C E N E R G Y A G E N C Y INVESTIGATION OF AN ACCIDENTAL EXPOSURE OF RADIOTHERAPY PATIENTS IN PANAMA Report of a Team of Experts 26 May–1 June 2001 The following States are Members of the International Atomic Energy Agency: AFGHANISTAN GHANA PAKISTAN ALBANIA GREECE PANAMA ALGERIA GUATEMALA PARAGUAY ANGOLA HAITI PERU ARGENTINA HOLY SEE PHILIPPINES ARMENIA HUNGARY POLAND AUSTRALIA ICELAND PORTUGAL AUSTRIA INDIA QATAR AZERBAIJAN,REPUBLIC OF INDONESIA REPUBLIC OF MOLDOVA BANGLADESH IRAN,ISLAMIC REPUBLIC OF ROMANIA BELARUS IRAQ RUSSIAN FEDERATION BELGIUM IRELAND SAUDI ARABIA BENIN ISRAEL SENEGAL BOLIVIA ITALY SIERRA LEONE BOSNIA AND HERZEGOVINA JAMAICA SINGAPORE BRAZIL JAPAN SLOVAKIA BULGARIA JORDAN SLOVENIA BURKINA FASO KAZAKHSTAN SOUTH AFRICA CAMBODIA KENYA SPAIN CAMEROON KOREA,REPUBLIC OF SRI LANKA CANADA KUWAIT SUDAN CENTRAL AFRICAN LATVIA SWEDEN REPUBLIC LEBANON SWITZERLAND CHILE LIBERIA SYRIAN ARAB REPUBLIC CHINA LIBYAN ARAB JAMAHIRIYA THAILAND COLOMBIA LIECHTENSTEIN THE FORMER YUGOSLAV COSTA RICA LITHUANIA REPUBLIC OF MACEDONIA COTE D’IVOIRE LUXEMBOURG TUNISIA CROATIA MADAGASCAR TURKEY CUBA MALAYSIA UGANDA CYPRUS MALI UKRAINE CZECH REPUBLIC MALTA UNITED ARAB EMIRATES DEMOCRATIC REPUBLIC MARSHALL ISLANDS UNITED KINGDOM OF OF THE CONGO MAURITIUS GREAT BRITAIN AND DENMARK MEXICO NORTHERN IRELAND DOMINICAN REPUBLIC MONACO UNITED REPUBLIC ECUADOR MONGOLIA OF TANZANIA EGYPT MOROCCO UNITED STATES OF AMERICA EL SALVADOR MYANMAR URUGUAY ESTONIA NAMIBIA UZBEKISTAN ETHIOPIA NETHERLANDS VENEZUELA FINLAND NEW ZEALAND VIET NAM FRANCE NICARAGUA YEMEN GABON NIGER YUGOSLAVIA GEORGIA NIGERIA ZAMBIA GERMANY NORWAY ZIMBABWE The Agency’s Statute was approved on 23 October 1956 by the Conference on the Statute of the IAEA held at United Nations Headquarters, New York; it entered into force on 29 July 1957. The Headquarters of the Agency are situated in Vienna. Its principal objective is “to accelerate and enlarge the contribution of atomic energy to peace,health and prosperity throughout the world’’. © IAEA,2001 Permission to reproduce or translate the information contained in this publication may be obtained by writing to the International Atomic Energy Agency, Wagramer Strasse 5, P.O. Box 100, A-1400Vienna,Austria. Printed by the IAEA in Austria August 2001 STI/PUB/1114 INVESTIGATION OF AN ACCIDENTAL EXPOSURE OF RADIOTHERAPY PATIENTS IN PANAMA Report of a Team of Experts 26 May–1 June 2001 INTERNATIONAL ATOMIC ENERGY AGENCY VIENNA,2001 VIC Library Cataloguing in Publication Data Investigation of an accidental exposure of radiotherapy patients in Panama / report of a Team of Experts,26 May–1 June 2001. — Vienna :International Atomic Energy Agency,2001. p. ; 24 cm. STI/PUB/1114 ISBN 92–0–101701–4 Includes bibliographical references. 1. Radiotherapy — Accidents — Panama. Radiation — Physiological effect. I. International Atomic Energy Agency. VICL 01–00270 FOREWORD Early in 2001, serious accidental exposures involving patients undergoing radiotherapeutic procedures were discovered in Panama. The Government of Panama requested assistance from the IAEA under the terms of the Convention on Assistance in the Case of a Nuclear Accident or Radiological Emergency. The IAEA immediately notified the World Health Organization (WHO) and assembled and sent to Panama a team of senior experts from France, Japan, the USA and the IAEA, as well as a senior expert from the Russian Federation nominated by WHO. The expert team was requested to ensure that the “radiation source(s) involved in the accident was (were) in a safe and secure condition”; to “evaluate the doses incurred by the affected patients”; undertake a medical evaluation of the affected patients’prognosis and treatment; and to “identify issues on which the IAEA could offer to provide and/or co-ordinate assistance with a view to minimizing the consequences of the accident”. In addition, the Minister of Health of Panama had requested assistance from the Pan American Health Organization (PAHO/WHO), and a PAHO officer supported the expert team. This report contains the expert team’s assessment of the accidental exposure. The IAEA is very grateful to the Government of Panama for giving it the opportunity to assist in the aftermath of the accidental exposure described in this report and, as a consequence, to draw valuable lessons that can be shared with the international community worldwide. In particular,the IAEA wishes to express its thanks to the Panamanian Minister of Health and the Director General of Public Health, to the Director of the Instituto Oncológico Nacional (ION), to the Department of Radiation Health of the Social Security Complex Hospital and to the staff of all the Panamanian organizations which collaborated with the expert team. The IAEA is also very grateful to the members of the expert team for their dedication in carrying out their task and for their contribution to the development and review of this report. The IAEA wishes to express its thanks to: the Department of Radiology, School of Medicine, of the University of New Mexico, Albuquerque, USA; to the Département de Radiothérapie of the Institut Curie, Paris, and to the Institut de Protection et de Sûreté Nucléaire, Fontenay-aux-Roses, France; the Research Centre for Radiation Emergency Medicine of the National Institute of Radiological Sciences, Chiba, Japan; and to the Hematologic Department of the Russian Scientific Research Centre, Moscow, (a collaborating centre of WHO) for making their staff available for this mission. The IAEA is also grateful to PAHO for its readiness to collaborate fully with the expert team. The members of the team, as well as the names of the supporting experts, are given below: TEAM OF EXPERTS Akashi,M. Research Center for Radiation Emergency Medicine of the National Institute of Radiological Sciences, Chiba, Japan Cosset,J.-M. Section Médicale et Hospitalière, Département de Radiotherapie,Service B, Institut Curie,Paris,France; Member of Committee 3 of the International Commission on Radiological Protection (ICRP) Gourmelon,P. Commissariat á l’Energie Atomique, Centre d’Etudes Nucléaires de Fontenay-aux-Roses, Institut de Protection et de Sûreté Nucléaire, Fontenay-aux-Roses,France Konchalovsky,M.V. Hematologic Department of the Scientific Research (representing WHO) Center of the Russian Federation, Moscow, Russian Federation Mettler,F.A.,Jr., Department of Radiology, (Chairman) The University of New Mexico, School of Medicine, Albuquerque, New Mexico, United States of America; Delegate of USA to UNSCEAR; Member of the Main Commission and Chairman of Committee 3 of the ICRP Ortiz López,P. Radiation Safety Section, (Team co-ordinator) Division of Radiation and Waste Safety, International Atomic Energy Agency; Member of Committee 3 of the ICRP Vatnitsky,S. Dosimetry and Medical Radiation Physics Section, Division of Human Health,International Atomic Energy Agency SUPPORTING EXPERTS Pan American Health Organization Borrás,C. Program of Essential Drugs and Technology, Division of Health Systems and Services Development, Pan American Health Organization, Washington,D.C.,United States of America Panamanian Government Arenas,E. Médica Epidemióloga,Ministerio de Salud (MINSA) Barés,J.P. Director General,Instituto Oncológico Nacional (ION) Gibbs,E. Jefe del Departamento de Salud Radiológica, Caja de Seguro Social (CSS) López,R.I. Médico Oncólogo del ION Morales,E. Director General de Salud,MINSA Pinzón,N. Subdirectora del ION Panamanian experts Bedoya,R. Técnico de Salud Radiológica CSS Bolaños,V. Técnico de Salud Radiológica CSS De Infante,M. Técnico de Salud Radiológica CSS Douglas,A. Técnico de Salud Radiológica CSS Fernández,M. Técnico de Salud Radiológica CSS Fisher,V. Técnico de Salud Radiológica CSS Scotland,E. Técnico de Salud Radiológica CSS Terán,L.A. Técnico de Salud Radiológica CSS Tuñón,E. Técnico de Salud Radiológica CSS EDITORIAL NOTE This report is based on information made available by or through the Panamanian authorities. The report does not address questions of responsibility,legal or otherwise,for acts or omissions on the part of any person. Although great care has been taken to maintain the accuracy of information contained in this report, neither the IAEA nor its Member States assume any responsibility for consequences which may arise from its use. The use of particular designations or countries or territories does not imply any judgement by the publisher,the IAEA,as to the legal status of such countries or territories,of their authorities and institutions or of the limitation of their boundaries. The mention of names of specific companies or products (whether or not indicated as registered) does not imply any intention to infringe proprietary rights, nor should it be construed as an endorsement or recommendation on the part of the IAEA. Material made available by persons who are in contractual relation with governments is copyrighted by the IAEA, as publisher, only to the extent permitted by the appropriate national regulations. CONTENTS EXECUTIVE SUMMARY . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 The accidental exposure . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 Lessons and recommendations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2 1. INTRODUCTION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7 1.1. Background . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7 1.2. Objectives . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9 1.3. Scope . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9 1.4. Structure . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9 2. BACKGROUND INFORMATION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10 2.1. Radiotherapy departments in Panama . . . . . . . . . . . . . . . . . . . . . . 10 2.2. The Radiotherapy Department at the Instituto Oncológico Nacional . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10 2.2.1. External beam radiotherapy . . . . . . . . . . . . . . . . . . . . . . . . 11 2.2.2. Brachytherapy . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13 2.3. Treatment planning system . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14 2.4. Radiation protection infrastructure and regulatory control . . . . . . . 15 2.4.1. Authorization of the Radiotherapy Department . . . . . . . . . . 16 2.5. History of recent audits of the Radiotherapy Department . . . . . . . . 16 2.5.1. Audit in February 1999 . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16 2.5.2. Audit in February 2001 . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18 2.5.3. Results of IAEA/WHO TLD postal dose quality audits performed at the ION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19 3. THE ACCIDENTAL EXPOSURE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19 3.1. Initiating event . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19 3.2. Discovery of the problem . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23 4.. RESPONSE TO THE ACCIDENTAL EXPOSURE . . . . . . . . . . . . . . . . 24 4.1. Actions taken upon discovery of the error . . . . . . . . . . . . . . . . . . . 24 4.2. Response from the IAEA . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25