practical to approach planning in terms of a strategy that is adapted to the availability of resources. The purpose of the present publication is to make the case for an adequate level of radiotherapy to meet current and future needs worldwide. It presents an overview of the ideas shared by the IAEA in more technical publications. This publication presents an overview of the major topics and issues to be taken into account when planning and implementing radiotherapy services. 9 It has been planned with the health manager in mind, with the understanding that while the planning of cancer radiotherapy services is normally undertaken by managers, it should also involve collaboration with technical experts who have experience in the field. The chapters in this book present topics of current importance to the general discussion of radiotherapy services. Each chapter has been written by an author, or authors, with direct experience and expertise in that particular area. The topics are addressed from a global perspective. REFERENCES [I.1] GOLDBERG, S.W., LONDON, E.S., Zur Frage der Beziehungen zwischen Becquerel-strahlen und Hautaffectionen, Dermatol. Z. 10 (1903) 457–462. [I.2] LENNMALM, F. (Ed.), Fördhandlingar vid Svenska Lakare–Sallskapets Sammanskomster ar 1899, Isaac Marcus, Stockholm (1900) 205–209. [I.3] MOLLER, T.R., et al., A prospective survey of radiotherapy practice 2001 in Sweden, Acta Oncol. 42 (2003) 387–410. [I.4] RODEMANN, H.P., WOUTERS, B.G., Molecular and translational radiation biology/oncology: What’s up? Radiother. Oncol. 99 (2011) 257–261. [I.5] STRATTON, M.R., Exploring the genomes of cancer cells: Progress and promise, Science 331 (2011) 1553–1558. [I.6] INTERNATIONAL ATOMIC ENERGY AGENCY, DIRAC (Directory of Radiotherapy Centres), Expanding global access to radiotherapy, Lancet Oncol. Comm. 16 10 (2015) 1153–1186. [I.8] INTERNATIONAL ATOMIC ENERGY AGENCY, Setting Up a Radiotherapy Programme: Clinical, Medical Physics, Radiation Protection and Safety Aspects, IAEA, Vienna (2008). [I.9] INTERNATIONAL ATOMIC ENERGY AGENCY, Planning National Radiotherapy Services: A Practical Tool, IAEA Human Health Series No. 14, IAEA, Vienna (2010). [I.10] ROSENBLATT, E., et al., Radiation therapy utilization in middle-income countries, Int. J. Radiat. Oncol. Biol. Phys. 96 25 (2016) S37. [I.11] WORLD HEALTH ORGANIZATION, Political Declaration of the High-level Meeting of the General Assembly on the Prevention and Control of Non-communicable Diseases, WHO, Geneva (2011), [I.12] INTERNATIONAL ATOMIC ENERGY AGENCY, Dosimetry and Medical Radiation Physics (DMRP): About DMRP, http://www-naweb.iaea.org/nahu/DMRP/about.html 10 [I.13] INTERNATIONAL ATOMIC ENERGY AGENCY, Dosimetry and Medical Radiation Physics (DMRP): The IAEA’s Dosimetry Laboratory, http://www-naweb.iaea.org/nahu/DMRP/laboratory.html [I.14] INTERNATIONAL ATOMIC ENERGY AGENCY, Nuclear Medicine and Diagnostic Imaging (NMDI): About NMDI, http://www-naweb.iaea.org/nahu/NM/about.html Part II RADIOTHERAPY IN CANCER CARE 13 Chapter 1 RADIOTHERAPY IN CANCER CARE E. Rosenblatt, E. Zubizarreta, R. Camacho, B. Vikram 1.1. INTRODUCTION Cancer control, cancer care and cancer treatment are three different concepts, although the terms are often used interchangeably. Cancer control is the reduction in the incidence, morbidity and mortality of cancer, as well as the improvement in the quality of life of cancer patients and their families. As such, cancer control includes actions relating to prevention, early detection and screening, diagnosis, treatment and palliative care. Cancer care includes all actions and interventions aimed at supporting, assisting and treating cancer patients. Cancer care includes cancer treatment, but also other forms of support such as nutrition, symptom relief, speech therapy, physiotherapy, stoma care, nursing care, lymphoedema care and psychosocial care. Cancer treatment includes medical interventions aimed at the cure or palliation of a patient who has been diagnosed with cancer. As such, cancer treatment modalities include surgery, radiotherapy, systemic therapies such as chemotherapy, hormone therapy, immunotherapy, gene therapy and other investigational strategies. Cancer is a term used for diseases in which abnormal cells divide without control and are able to invade other tissues. Cancer cells can spread to other parts of the body through the blood and lymphatic system. Cancer is not just one disease, but many diseases. There are more than a hundred different types of cancer. Most cancers are named for the organ or type of cell from which they start — for example, cancer that begins in the basal cells of the skin epidermis is called basal cell carcinoma. Cancer types can be grouped into broader categories according to the type of cells or tissue of origin. The main types are carcinomas, sarcomas, melanomas, lymphomas and leukaemias. With ongoing developments in genetic profiling, it is possible that in the future the response of cancers to therapy will be assessed by looking at their genetic expression rather than their histological type. All cancers begin in cells, the body’s basic unit of life. To understand cancer, it is helpful to know what happens when normal cells become cancer cells. The body is made up of many types of cells. Cells evolve and differentiate during embryonic development from relatively undifferentiated embryonic stem 14 cells through a complex process of signalling. These cells grow and divide in a controlled manner to produce more cells as they are needed to maintain the body structure and functions. When cells become old or damaged, they die and are replaced by new cells. Sometimes, this orderly process goes wrong. The genetic material (particularly the nuclear deoxyribonucleic acid, or DNA) of a cell can become damaged or changed, producing mutations that affect normal cell growth and division. When this happens, cells do not die when they should and new cells form when the body does not need them. The extra cells will then form a non-functional mass of tissue called a tumour. These cells, the cancer cells, not only have lost the capacity to respond to normal control mechanisms, but for this very reason they are locally invasive, invade, push, infiltrate and destroy other tissues and have the potential to spread following the lymphatic channels and blood vessels to create distant deposits of cancer known as distant metastases. The cellular origin of cancer was described by Virchow in 1863 [1.1]. The molecular structure of DNA was elucidated by J.D. Watson and F. Crick in 1953 [1.2]. At that time, the relative survival rate of cancer patients as a whole in the United States of America was 35% [1.3]. Hybridomas for the production of monoclonal antibodies were developed in 1995, and by this time the relative survival rate was 50%. The year 2005 saw the first absolute decrease in the total number of deaths from cancer in the United States of America. That year the relative survival rate was 68%. These figures highlight a steady improvement in the relative survival rates for cancer in an industrialized country, an improvement associated with ongoing medical research. The aetiology of cancer is multifactorial, with genetic, environmental and lifestyle factors interacting to induce and maintain the process of malignant transformation. Knowledge of cancer genetics is rapidly improving our understanding of cancer biology, helping to identify at-risk individuals, furthering the ability to characterize malignancies, establishing treatment tailored to the molecular fingerprint of the disease, and leading to the development of new therapeutic modalities. This expanding knowledge base has implications for all aspects of cancer management, including prevention, screening and treatment. The ultimate cancer cure will be possible when a therapeutic intervention will induce ‘cell kill’ limited to the malignant cells only, while sparing the non-malignant cells; a ‘magic bullet’, like many antibiotics against bacterial infections. Current research into targeted therapies, genetic research and gene manipulation may be steps in that direction. 15 1.2. RADIOTHERAPY IN THE CONTEXT OF CANCER CONTROL Radiotherapy is the medical use of ionizing radiation in the treatment of disease, mostly cancer but also non-malignant disease. The historical development of the use of radiation as a medical