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Moreira LAR et al .
192 Rev Assoc Med Bras 2016; 62(2):192-196
REVIEW ARTICLE
Cardiovascular effects of radiotherapy on the patient with cancer
Leonardo Augusto Robert Moreira1, Eduardo Nani Silva², Mario Luiz Ribeiro³, Wolney de Andrade M artins4*
1Specialist degree in Cardiology from Universidade Federal Fluminense (UFF), Rio de Janeiro, RJ, Brazil
²MSc in Medicine (Cardiology) from UFF. Adjunct Professor, Department of Internal Medicine, UFF, Rio de Janeiro, RJ, Brazil
³MSc in Medicine (Cardiology) from UFF. Assistant Professor, Department of Internal Medicine, UFF, Rio de Janeiro, RJ, Brazil
4PhD in Sciences (Cardiology) from Universidade de São Paulo. Professor, Medical School, UFF, Rio de Janeiro, RJ, Brazil
Summary
Study conducted at Curso de
Pós-graduação em Ciências
Cardiovasculares da Universidade Federal
Fluminense (UFF), Niterói, RJ, Brazil
Article received: 7/5/2014
Accepted for publication: 10/21/2014
*Correspondence:
Address: Rua Marquês do Paraná, 303,
6º andar, Centro
Niterói, RJ – Brazil
Postal code: 24030-215
Financial support: The Cardio-oncology
Study Group of UFF receives incentives
for research projects from the Carlos
Chagas Filho Foundation for Support
of Research in the State of Rio
de Janeiro (Faperj)
The incidence of cancer (CA) has increased globally and radiotherapy (RT) is a
vital component in its treatment. Cardiovascular injuries induced by RT in the
treatment of thoracic and cervical CA have been causing problems in clinical
practice for decades, and are among the most serious adverse effects of radia-
tion experienced by the growing number of cancer survivors. This article pres-
ents a review on the Lilacs, Scielo and Pubmed databases of the main cardiovas-
cular injuries, their mechanisms, clinical presentations, treatments and
prevention proposals. Injuries caused by RT include diseases of the pericardium,
coronary artery disease, valvular disease, myocardial disease with systolic and di-
astolic dysfunction, conduction disorders, and carotid artery and great vessels
disease. Thoracic and cervical irradiation increases cardiovascular morbidity and
mortality. Despite the great progress in the improvement of RT techniques, to-
tally excluding prime areas of the cardiovascular system from the irradiation
field is not yet possible. Guidelines must be created for monitoring, diagnosis
and treatment of patients with CA treated with RT.
Keywords: Radiotherapy, radiation injuries, cardiovascular diseases.
Introduction
Cancer (CA) is characterized by uncontrolled cell prolif-
eration that expresses varying degrees of differentiation
to the precursor cells. In general, CA has a natural and ir-
reversible history and autonomous growth, which per-
sists even after cessation of the stimulus that produced
it. CA has the property of invading adjacent tissues and
causing metastasis, where subpopulations of malignant
cells grow and invade tissues again.1
According to global estimates by the Globocan proj-
ect of the International Agency for Research on Cancer
and the World Health Organization, in 2012 there were
14.1 million new cases of CA and 8.2 million deaths due
to this disease worldwide. For 2030, the estimated glob-
al incidence of CA is 21.4 million cases and 13.2 million
deaths. In Brazil, the estimate for the period 2014-2015
is approximately 576,000 new cases of CA including
non-melanoma skin cancer. Chart 1 contains the esti-
mated incidence of the main thoracic and cervical tu-
mors for Brazil in 2014 according to the National Can-
cer Institute.2
CHART 1Estimated new cases of cancer in the cervical or
thoracic sites for the year 2014 in Brazil. Source: Instituto
Nacional do Câncer.2
Cancer’s primary location Estimated new cases
Female breast 57,120
Trachea, bronchi and lungs 27,330
Larynx 7,640
Esophagus 10,780
Hodgkin’s lymphoma 2,180
Thyroid 9,200
Stomach 20,390
Radiation therapy (RT) is a vital component in the treat-
ment of CA. It arose from the discovery of x-rays by Wil-
helm Röentgen in 1895, and radioactivity, by Henry Bec-
querel, in 1896. When radiation interacts with the air or
matter, it transfers a sufficient amount of power to the
electrons of the medium to rip them from the atom. This
process is called ionization. The density of this process
depends on the charge, the mass and the speed of the