Download What Is Cancer Screening?

‫بسم هللا الرحمن‬
‫الرحيم‬
INTRODUCTION
Cancer
deaths seven million
half a million  die from cancer each year in the
United States (US) alone
It is estimated that 50 percent of cancer is
preventable
INTRODUCTION
risk
factors (account for two-thirds of all
cancers in the US
–tobacco use,
–excess weight,
–poor diet,
–inactivity
INTRODUCTION
nine
modifiable risks were identified as the cause of
35 percent of cancer deaths worldwide:
–smoking,
–alcohol use,
Harvard Report on
–diet low in fruit and vegetables,
Cancer Prevention
Volume 2:
–excess weight,
Prevention of
–inactivity,
Human Cancer.
Cancer Causes
–unsafe sex,
and Control
–urban air pollution,
1997; 8:S1.
–use of solid fuels, and
–contaminated injections in health-care settings
INTRODUCTION
Lifestyle
issues which promote cancer
are also risk factors for other diseases,
such as stroke, heart disease, and
diabetes.
TOBACCO
USE
–kills approximately 5 million people each year
–mostly through
malignancy,
cardiovascular, and
respiratory disease
–Approximately one-half of all smokers die of a
tobacco-related disease, and
–adult smokers lose an average of 13 years of life
due to this addiction
–What
Is Cancer Screening?
–Evaluation of a Screening Test
–Breast Cancer Screening
–Cervical Cancer Screening
–Colorectal Cancer Screening
–Skin Cancer Screening
–Prostate Cancer Screening
–Lung Cancer Screening
–Adherence to Cancer Screening
–Future of Screening
The
goal of cancer screening
–detect cancer at an early stage
when it is treatable and curable
For
a screening test to be useful:
–should detect cancer earlier than would occur
otherwise,
–should be evidence that earlier diagnosis results
in improved outcomes
Advances
in genetics and molecular biology
–will make it possible to detect cancer at earlier
and earlier stages along the carcinogenesis
pathway
–the line between prevention and screening may
narrow further, as it has for colorectal and
cervical cancers
The
National Cancer Policy Board
estimated that appropriate use of
screening among
–persons aged 50 and older could reduce
the mortality from colorectal cancer by
30% to 80%;
–women aged 50 and older could reduce
mortality from breast cancer by 25% to
30%,
–women aged 18 and older could reduce
the rate of cervical cancer mortality by
20% to 60%.
What Is Cancer Screening?
lead to early detection of asymptomatic or
unrecognized disease
acceptable
inexpensive tests or examinations
in a large number of persons
expeditiously to separate apparently well persons
who probably have disease from those who probably
do not.
What Is Cancer Screening?
The main objective of cancer screening is to:
– reduce morbidity and mortality from a particular cancer
among persons screened
What Is Cancer Screening?
Characteristics of Screening Tests versus Diagnostic
Tests
Screening
Diagnosis
Applied to asymptomatic
groups
Applied to symptomatic
individuals
Lower cost per test
Higher cost; all necessary tests
applied to identify disease
Lower yield per test
Higher probability of case
detection
Lower adverse
consequences of error
Failure to identify true positives
can delay treatment and worsen
prognosis
What Is Cancer Screening?
cancers
suitable for screening
–High morbidity and mortality,
–high prevalence in a detectable preclinical
state,
–possibility of effective and improved
treatment because of early detection, and
–availability of a good screening test with
high sensitivity and specificity,
–low cost, and
–little inconvenience and discomfort
What Is Cancer Screening?
cancers suitable for screening
–Breast CA
–Cervical CA
–colorectal CA
–Skin cancer
Evaluation of a Screening Test
If
the test is abnormal,
–what are the chances that disease is present?
If
the test result is normal,
–what are the chances that disease is absent?
Evaluation of a Screening Test
The validity of a screening test
–Sensitivity and specificity address the validity of
screening tests
Sensitivity is the probability of testing positive if the
disease is truly present.
–As sensitivity increases, false-negative decreases
Specificity is the probability of screening negative if
the disease is truly absent.
–A highly specific test false-positive decreases
Evaluation of a Screening Test
The validity of a screening test
–Predictive value
is a function of sensitivity, specificity, and prevalence
of disease
PV+ is an estimate of test accuracy in predicting
presence of disease;
PV– is an estimate of the accuracy of the test in
predicting absence of disease
Definitions of Criteria for Evaluating a Screening Test
Truth (Diagnostic Classification)
Screening Test Results
Cancer Present
Cancer Absent
Positive
TP
FP
Negative
FN
TN
Sensitivity = TP/TP + FN x 100
Specificity = TN/FP + TN x 100
PV+ = TP/TP + FP x 100
PV– = TN/TN + FN x 100
Accuracy = TP + TN/TP + TN + FP + FN x 100
FN, false-negative (number of subjects with cancer who are incorrectly
classified as cancer-free by the test);
FP, false-positive (number of cancer-free subjects who are incorrectly classified
as having cancer by the test);
PV, predictive value; TN, true-negative
(number of cancer-free subjects who are correctly classified by the test);
TP, true-positive (number of subjects with cancer who are correctly classified
Evaluation of a Screening Test
–The optimal outcome is a reduction in cancer
mortality
Evaluation of a Screening Test
Measures of Effectiveness
–Potential negative effects of screening include
 physical, economic, and psychological consequences
of false-positives and false-negatives,
the potential for overdiagnosis,
the potential carcinogenic effects of screening,
the labeling phenomenon.
Evaluation of a Screening Test
Measures of Effectiveness
–Potential negative effects of screening include
 physical, economic, and psychological consequences
of false-positives and false-negatives,
the potential for overdiagnosis,
the potential carcinogenic effects of screening,
the labeling phenomenon.
Evaluation of a Screening Test
Measures of Effectiveness
–Physicians should engage patients in discussions
of the risks and benefits of cancer screening
Table 22-5: Screening Guidelines for Breast, Colorectal, Prostate, and Cervical Cancers for Selected Health Care Organizations
Ty
pe
of
Ca
nc
er
American Cancer Society20
U.S. Preventive Services Task Force3
National Cancer Institute's Physician
Data Query (PDQ) System1
Br
ea
st
ca
nc
er
Annual mammography for women aged 40–69
y. No age cutoff. To the extent possible, a CBE
should be performed at the time of
mammography. Monthly BSE.136 Women aged
20–39 y should have a CBE from a health
professional every 3 y and should perform BSE
monthly.20
Recommends screening mammogram, with or
without CBE, every 1–2 y.
Mammography every 1–2 y for women age 40
y and older. Women at higher risk should talk
with their physicians about schedule.
Ce
rvi
cal
ca
nc
er
For all women who are, or have been, sexually
active or who have reached age 21 y, Pap test
and pelvic examination yearly with Pap tests
or every 3 y with liquid-based tests. At or
after age 30 y, women who have had 3 normal
tests can be screened every 2–3 y. Women
with risk factors (e.g., HPV infection) may
require more frequent screening. Screening is
not necessary for women who have had total
hysterectomies unless the surgery was for
treatment of cervical cancer.
Pap test every 1–3 y for all women who are
sexually active and/or have a cervix. No
evidence to support an upper limit, but age 65
y can be defended in women with a history of
normal and regular Pap tests.
Evidence strongly suggests a decrease in
mortality for regular screening with Pap tests
in women who are sexually active or who have
reached age 18 y. The upper limit at which
such screening ceases to be effective is
unknown.
Col
ore
cta
l
ca
nc
er
One of the following schedules for men and
women aged 50 y and over at average risk:
FOBT yearly; sigmoidoscopy every 5 y; FOBT
+ sigmoidoscopy every 5 y; colonoscopy
every 10 y; DCBE every 5 y. Those at high
risk for colorectal cancer should begin
screening earlier and/or more frequently.
Screening for colorectal cancer is strongly
recommended for men and women aged 50 y
and over. Several screening modalities are
effective. Good evidence has been shown that
periodic FOBT reduces mortality from
colorectal cancer, and there is fair evidence
that sigmoidoscopy alone or in combination
with FOBT reduces mortality. No direct
evidence has been shown for either
colonoscopy or DCBE.
FOBT either annually or biennially using
rehydrated or nonrehydrated stool specimens
in people aged 50 y and over decreases
mortality for colorectal cancer. Regular
screening by sigmoidoscopy in people over
age 50 y may decrease mortality from
colorectal cancer. Evidence is insufficient to
determine the optimal interval for such
screening.
Pro
sta
te
ca
nc
er
PSA test and DRE should be offered annually,
beginning at age 50 y, to men who have a life
expectancy of at least 10 y. Men at high risk
for cancer should start screening at 45 y. Men
should be given the information needed to
make informed decisions about prostate
cancer screening.
Evidence is insufficient to recommend for or
against routine screening for prostate cancer
using PSA testing or DRE.
Evidence is insufficient to establish that a
decrease in mortality occurs with screening by
DRE, transrectal ultrasound, or PSA.
Screening Guidelines for Breast, Colorectal, Prostate, and Cervical Cancers
for Selected Health Care Organizations
Type
of
Cancer
American Cancer
Society
U.S. Preventive
Services Task
Force
National Cancer
Institute's Physician
Data Query (PDQ)
System
Breast
cancer
Annual mammography
for women aged 40–69
y. No age cutoff. To the
extent possible, a CBE
should be performed at
the time of
mammography. Monthly
BSE.Women aged 20–39
y should have a CBE
from a health
professional every 3 y
and should perform BSE
monthly.20
Recommends
screening
mammogram, with or
without CBE, every
1–2 y.
Mammography every 1–2
y for women age 40 y and
older. Women at higher
risk should talk with their
physicians about
schedule.
Table 22-5: Screening Guidelines for Breast, Colorectal, Prostate, and Cervical Cancers
for Selected Health Care Organizations
Type
of
Cance
r
American Cancer
Society20
U.S. Preventive Services
Task Force3
National Cancer Institute's
Physician Data Query
(PDQ) System1
Cervic
al
cancer
For all women who are, or
have been, sexually active
or who have reached age
21 y, Pap test and pelvic
examination yearly with
Pap tests or every 3 y with
liquid-based tests. At or
after age 30 y, women
who have had 3 normal
tests can be screened
every 2–3 y. Women with
risk factors (e.g., HPV
infection) may require
more frequent screening.
Screening is not necessary
for women who have had
total hysterectomies
unless the surgery was for
treatment of cervical
cancer.
Pap test every 1–3 y for all
women who are sexually
active and/or have a cervix.
No evidence to support an
upper limit, but age 65 y
can be defended in women
with a history of normal and
regular Pap tests.
Evidence strongly suggests a
decrease in mortality for
regular screening with Pap
tests in women who are
sexually active or who have
reached age 18 y. The upper
limit at which such screening
ceases to be effective is
unknown.
Type of
Cancer
American
Cancer
Society20
U.S. Preventive
Services Task Force3
National Cancer
Institute's Physician
Data Query (PDQ)
System1
Colorectal
cancer
One of the
following
schedules for
men and women
aged 50 y and
over at average
risk: FOBT
yearly;
sigmoidoscopy
every 5 y; FOBT
+ sigmoidoscopy
every 5 y;
colonoscopy
every 10 y;
DCBE every 5 y.
Those at high
risk for colorectal
cancer should
begin screening
earlier and/or
more frequently.
Screening for colorectal
cancer is strongly
recommended for men
and women aged 50 y
and over. Several
screening modalities are
effective. Good evidence
has been shown that
periodic FOBT reduces
mortality from colorectal
cancer, and there is fair
evidence that
sigmoidoscopy alone or in
combination with FOBT
reduces mortality. No
direct evidence has been
shown for either
colonoscopy or DCBE.
FOBT either annually or
biennially using
rehydrated or
nonrehydrated stool
specimens in people aged
50 y and over decreases
mortality for colorectal
cancer. Regular screening
by sigmoidoscopy in
people over age 50 y may
decrease mortality from
colorectal cancer.
Evidence is insufficient to
determine the optimal
interval for such
screening.
Type of
Cancer
American
Cancer
Society20
U.S. Preventive
Services Task Force3
National Cancer
Institute's Physician
Data Query (PDQ)
System1
Prostate
cancer
PSA test and
DRE should be
offered annually,
beginning at age
50 y, to men who
have a life
expectancy of at
least 10 y. Men
at high risk for
cancer should
start screening
at 45 y. Men
should be given
the information
needed to make
informed
decisions about
prostate cancer
screening.
Evidence is insufficient to
recommend for or against
routine screening for
prostate cancer using PSA
testing or DRE.
Evidence is insufficient to
establish that a decrease
in mortality occurs with
screening by DRE,
transrectal ultrasound, or
PSA.
Breast
Cancer Screening
lifetime breast cancer incidence is 7.8%,
Widely
accepted techniques for breast cancer
screening,
–mammography,
–clinical breast examination (CBE), and
–breast self-examination (BSE).
–No cancer screening test has been studied more than
mammography (with or without CBE).
Breast
Most
Cancer Screening
trials have included women in their 40s,
 two trials began accrual at age 45.
One of the Canadian trials [the first National Breast
Cancer Screening Study (NBSS1)] was designed to
examine mammography and CBE versus usual care
for women in their 40s
‫معاینه بالینی‬
‫بدون عالمت‬
‫معاینه فیزیکی نرمال‬
‫در گروه با ریسک نرمال‬
‫سن بین ‪ 40-20‬سال‬
‫‪ CBE -1‬هر سه سال‬
‫‪ BSE -2‬دوره ای‬
‫سن بیش از ‪ 40‬سال‬
‫‪-1‬ساللیانه ‪CBE‬‬
‫‪-2‬ماموگرافی سالیانه‬
‫‪ BSE-3‬دوره ای‬
‫معاینه بالینی‬
‫بدون عالمت معاینه فیزیکی نرمال‬
‫ریسک باالی کانسر‬
‫ا‬
‫اشعه درمانی قبلی به قفسه صدری‬
‫سن بیش از‬
‫‪ 25‬سال‬
‫سن کمتر از‬
‫‪ 25‬سال‬
‫‪ -1‬مامو گرافی سالیانه‬
‫‪ +‬هر ‪ 12-6‬ماه ‪BCE‬‬
‫از ‪ 10-8‬سال بعد از‬
‫‪ xrt‬یا ‪ 40‬سالگی‬
‫‪CBE -1‬‬
‫سالیانه‬
‫‪BSE -2‬‬
‫دوره ای‬
‫ریسک ‪ 5‬ساله‬
‫سرطان پستان بیش‬
‫از ‪ %1.7‬در‬
‫خانمهای بیش از‬
‫‪ 35‬سال‬
‫‪ -1‬مامو گرافی سالیانه‬
‫‪ +‬هر ‪ 12-6‬ماه ‪BCE‬‬
‫‪ BSE -2‬دوره ای‬
‫‪ BSE -2‬دوره ای‬
‫‪-3‬در نظر گرفتن کاهش‬
‫ریسک‬
‫سابقه فامیلی شدید یا تمایل قوی‬
‫ژنتیکی‬
‫سن کمتر از ‪25‬‬
‫سال‬
‫سن بیشتر از‬
‫‪ 25‬سال‬
‫‪-1‬ماموگرافی سالیانه ‪ CBE+‬هر‬
‫‪ 12-6‬ماه‬
‫‪ BSE -2‬دوره ای‬
‫‪ MRI -3‬به عنوان کمک به‬
‫ماموگرافی و ‪BCE‬‬
‫‪-4‬در نظر گرفتن کاهش ریسک‬
‫‪ -1‬از ‪ 25‬سالگی در‬
‫‪HBOS‬‬
‫‪ 10-5-2‬سال بعد از تظاهر‬
‫در جوانترین بیمار فامیل‬
‫‪lCIS /Atypical‬‬
‫‪hyperplasia‬‬
‫‪-1‬‬
‫‪CBE‬‬
‫سالیانه‬
‫‪-2‬‬
‫‪BSE‬‬
‫دوره‬
‫ای‬
‫‪-1‬ماموگرافی‬
‫سالیانه‬
‫‪ CBE+‬هر‬
‫‪ 12-6‬ماه‬
‫‪BSE -2‬‬
‫دوره ای‬
‫‪-3‬در نظر‬
‫گرفتن کاهش‬
‫ریسک‬
‫معاینه بالینی‬
‫یافته مثبت در معاینه‬
‫توده یا سفتی‬
‫پوسته ریزی یا اکزما‬
‫ترشح از نیپل بدون توده‬
‫قابل لمس‬
‫تغییرات پوست‬
‫ترشح نوک پستان‬
‫اریتم‬
‫پوست پرتقالی‬
‫ضخیم شدن ‪/‬ندوالریته‬
‫‪BSCR-5‬‬
‫نامشخص یا‬
‫مشکوک‬
‫احتماال خوش‬
‫خیم‬
‫‪BRCR-6‬‬
‫‪BSCR-7‬‬
‫توده‬
‫سونوگرافی‬
‫‪BI‬‬‫=‪RADS‬‬
‫‪1-3‬‬
‫آسپیراسیون‬
‫کیست غیر‬
‫ساده یا عالمت‬
‫دار‬
‫‪BSCR-7‬‬
‫‪BSCR-1‬‬
‫اگر جدار‬
‫نامنظم و یا‬
‫توده کیست‬
‫باشد بیوپسی‬
‫اکسیژنال‬
‫توصیه می‬
‫شود‬
‫گزارش هر‬
‫تغییری توسط‬
‫بیمار‬
‫کیست‬
‫‪ 4-2‬ماه‬
‫پیگیری‬
‫‪BSCR-5‬‬
‫‪biopsy -‬‬‫‪>BSCR-5‬‬
‫پیشرفت یا‬
‫بزرگ شدن‬
‫‪BSCR-1‬‬
‫ثبات‬
‫ماموگرام‬
‫کیست بدون‬
‫عالمت یا ساده‬
‫بیوپسی بافتی‬
‫پیگیری هر‬
‫‪ 6-3‬ماه ‪-/+‬‬
‫ماموگرافی‬
‫برای ‪2-1‬‬
‫سال جهت‬
‫بررسی ثبات‬
‫سونوگرافی‬
‫نرمال‬
‫‪BSCR-16‬‬
‫‪BI‬‬‫‪rads=4‬‬
‫‪-5‬‬
‫توده یا‬
‫المپ‬
‫در بیش‬
‫‪30‬‬
‫سال‬
‫توده‪ :‬ریسک متوسط یا مشکوک‬
‫بیوپسی بافتی‬
‫تکه برداریی‬
‫اگر ‪CNB‬‬
‫مقدور نباشد‬
‫‪malignant‬‬
‫‪LCIS‬‬
‫‪Atypical‬‬
‫‪hyper‬‬
‫‪plasia‬‬
‫‪ ( CNB‬ترجیحا )‬
‫خوش خیم‬
‫ ‪LCIS‬‬‫بدخیم‬
‫مسیر زیر‬
‫مشکوک ‪atypical -‬‬
‫‪hyperplasia‬خوشخیم ولی‬‫گرافی مشکوک‪LCIS-‬‬
‫‪Atypical‬‬
‫‪hyperplas‬‬
‫‪ia‬‬
‫خوش خیم‬
‫روتین و‬
‫کاهش ریسک‬
‫کانسر‬
‫روتین‬
‫خوش خیم(هم در پاتولوژی و هم در‬
‫گرافی )‬
‫معاینه بالینی‬
‫‪-/+‬‬
‫سونوگرافی‬
‫هر ‪12-6‬‬
‫ماه برای ‪-1‬‬
‫‪ 2‬سال‬
‫تکه برداری‬
‫توسط‬
‫جراحی‬
‫ثبات‬
‫افزایش اندازه‬
‫معاینه روتین‬
‫((‪BSCR-1‬‬
‫بیوپسی مجدد‬
‫سونوگرافی‬
‫عدم مایع‬
‫‪FNA‬‬
‫سونوگرافی‬
‫آسپیراسیون ساده‬
‫بررسی مایع‬
‫)‪(BSCR-7‬‬
‫مایع(کیست)‬
‫برخورد معمول‬
‫(‪(BSCR-1‬‬
‫از بین رفتن نوده‬
‫مانند باال‬
‫از بین نرفتن توده‬
‫سن کمتر از ‪30‬‬
‫یرای ‪ 2-1‬سیکل‬
‫ماهیانه تحت نظر‬
‫باشد (برای بیماران‬
‫با ریسک کم‬
‫بدخیمی‬
‫توده یا سفتی در‬
‫پستان‬