Abril - 2017

adilha

CML

380

ssoc

ras

2017; 63(4):379-385

Patients with uterine cervix malignancies who are

referred for radiotherapy have advanced-stage disease,

which results in high rates of locoregional recurrence.

cases of cervical cancer, cytopathological examination

should be performed to control possible residual neoplasm

or recurrence of neoplasm after radiotherapy.

2,6,7

Follow-up of cervical cancer patients treated with

curative intent is based on the premise that early detec-

tion of a recurrence would result in decreased morbidity

and mortality from this disease. Currently, follow-up

protocols vary widely, especially in relation to the num-

ber of tests and intervals. There are no formal recom-

mendations for an ideal program to monitor these pa-

tients. However, the importance of performing periodic

exams (physical, cytopathological, colposcopic and im-

aging) is a consensus.

2,3,8

According to the handbook of gynecologic oncology

practice by Hospital A.C. Camargo (

Manual de condutas em

ginecologia oncológica

, 2010), clinical and colpocytological

reevaluations every 3-4 months in the first 2 years, with

intervals of 6 months from the third to the fifth year of

follow-up and annual return after 5 years, are recom-

mended for follow-up of patients irradiated due to cervi-

cal cancer, in addition to individualized imaging tests.

The use of radiotherapy as a treatment for cervical

cancer causes morphological changes in neoplastic and

nonneoplastic epithelial cells, as well as in stromal cells.

These alterations make it difficult to diagnose the re-

sidual lesion, resulting in a dilemma in cytopathological

routine.

Actinic cellular atypia may produce false-positive

results, but also false-negatives, given the difficulty in

collecting adequate samples due to changes in the anat-

omy of the cervix and vaginal canal, mainly caused by

brachytherapy.

Subjectivity in the interpretation of

changes is also a limitation of the method.

Based on the difficulties of cytopathologic evaluation

for the follow-up of patients treated with radiotherapy

for cervical cancer, our objective was to describe actinic

cytopathic effects in the follow-up of patients with cervi-

cal cancer after radiotherapy.

ethod

This paper was based on a structured review that includ-

ed the interval from June 2015 to April 2016, and followed

the methods proposed by Villas et al.

and Mendes et

al.,

aiming at an exploratory-descriptive study. Biblio-

graphic investigations were carried out through selection

and analysis of articles, list of authors and keywords, se-

lection of new articles focused on the analysis of biblio-

graphic references to previously selected documents, as

well as textbooks of recognized merit. The main purpose

of exploratory-descriptive studies is to characterize aspects

of a given research object compared to previously accu-

mulated knowledge. They are particularly suitable because

the object of study is not recurrent in the literature.

Data

collection included journals indexed in the following

databases: MedLine, LILACS, PsycINFO, SciELO Brasil,

and the CAPES Portal:

http://periodicos.capes.gov.br

There was no time limitation, but articles published be-

tween 2005 and 2016 were prioritized.

heoretical

basis

Conceptually, ionizing radiation consists of electromag-

netic waves with enough energy to cause electrons to

detach from atoms and molecules, changing their struc-

ture in a process known as ionization. As a result, they

become electrically charged. There are several types of

ionizing radiation and each has different penetration

power, causing different degrees of ionization in matter.

14,15

Ionizing radiation penetrates according to its type and

energy. While alpha particles can be blocked by a sheet of

paper, beta particles require a few millimeters of a mate-

rial such as aluminum, to block them, while high-energy

gamma radiation requires dense materials to block it,

such as lead or concrete.

14,15

Ionizing radiation can occur naturally, for example,

by the decomposition of natural radioactive substances

such as radon gas. The rate at which a radionuclide de-

composes (becomes less radioactive) is called half-life,

which is the time it takes for a radioactive material to

reduce its activity by half. Depending on the radionuclide,

this can range from fractions of a second to millions of

years. It is possible to measure radiation in various mate-

rials, even at very low levels, and the amount of measured

radioactivity is expressed as a concentration.

14,15

iological

effects

radiation

Ionizing radiation interacts with living matter in a process

that takes place at the atomic level. Biological molecules

are mainly constituted by atoms of carbon, hydrogen,

oxygen and nitrogen that can be ejected when irradiated.

The transformation of a macromolecule by the action of

radiation promotes harmful consequences that can be

observed in the cells. Likewise, the generation of new

chemical entities in the system also has an impact on the

irradiated cell. On the other hand, water molecules are the

most abundant in the human body, with about 2 x 10

molecules of water per kilogram, allowing us to state that,

in case of exposure to radiation, the molecules affected

in greater numbers will be those of water that suffer ra-