 |
Prostate Cancer Risk Assessment and
the UCSF-CAPRA Score
Prostate cancer is the most common cancer diagnosed among
American men, and causes more deaths annually among men than
any other tumor except lung cancer. However, only a small proportion
of prostate cancers diagnosed are ultimately lethal. A large
majority of men found to have prostate cancer ultimately die
of other causes, most commonly cardiovascular disease. All available
treatments for prostate cancer (surgery, radiation therapy, hormonal
therapy, and others) carry a risk of complications, side effects,
and other impacts to the patient's long-term quality of life.
Before making a decision regarding treatment for prostate cancer
it is important to estimate the likelihood
that a given tumor will recur after treatment, progress,
and pose a threat to life.
Risk Assessment Methods
Risk Assessment systems are not intended to replace individualized clinician-patient decision making, but rather to provide a straightforward instrument for facilitating disease risk classification in clinical decision making and in future research.
There are many approaches to risk assessment including the D'Amico
classification, a variety of nomograms and the UCSF-CAPRA
Score.
Risk classification (D'Amico): The classification
developed by D’Amico and
colleagues is one
of the most widely used and is a good
starting point for risk assessment. This system uses PSA
level (blood test), Gleason grade (microscopic appearance of
the cancer cells), and T stage (size of the tumor on rectal exam
and/or ultrasound) to group men as low, intermediate,
or high-risk.
Low-risk: PSA less than or equal to 10, Gleason score
less than or equal to 6, and clinical stage T1-2a
Intermediate
risk: PSA between 10 and 20, Gleason score 7, or clinical stage
T2b
High-risk: PSA more than 20, Gleason score
equal or larger than 8, or clinical stage T2c-3a
Limitations: Does not account
for multiple risk factors
For example,
Patient one: Gleason
3+4, PSA 3.2, stage T1c cancer in one
biopsy core
Patient two:
Gleason 4+3, PSA 19.2,
stage T2b cancer involving eight cores
• Both patients are classified as
intermediate risk, althought patient two
would have much higher disease risk.
Nomograms: Pioneered in prostate cancer by Kattan
and colleagues is an approach that incorporates multiple risk
variables to produce mathematical models that predict the likelihood
of disease recurrence or progression. The
models are often presented as nomograms, graphical calculating
devices that allow determination of the score based on values
presented on a paper table. Many such instruments
have been developed for prostate cancer.
Memorial Sloan-Kettering Cancer Center provides an on-line
calculator which allows some
of the models to be calculated. A few of these nomograms are
well known and have been validated in multiple settings.
Limitations: care must be taken
in interpreting the predictions from the calculators.
For example,
• A model
developed using data from patients treated by a high-volume
surgeon in a large city, may not be valid for
those treated by a lower-volume surgeon in rural area.
In general, nomograms developed using data from academic
series tend to be somewhat overly optimistic when applied
in the community practice setting.
• Each nomogram is developed using a different set of
patients in a different setting, and usually using different
definitions of cancer recurrence or progression. Because
the definitions of recurrence and progression are not consistent
across nomograms, scores
from the different treatment nomograms (e.g. pre-prostatectomy
and pre-brachytherapy) cannot be used to compare the likelihood
of a good result from one type of treatment versus another
type of treatment for an individual man. Each nomogram is deisgned
to give a prediction of treatment success only after a treatment
decision has already been made.
The UCSF-CAPRA score
In a effort to address the limitations of these approaches to
risk assessment UCSF developed the Cancer of the Prostate
Risk Assessment (UCSF-CAPRA) score. CAPRA is a
straightforward 0 to 10 score. It is nearly as easy to calculate
as the D’Amico
classification, yet with accuracy comparable to the best nomograms.
A CAPRA score is valid across multiple treatment
approaches and it predicts an individual's
likelihood of metastasis, cancer-specific mortality, and overall
mortality.
The score is calculated using points assigned to: age at diagnosis,
PSA at diagnosis, Gleason score of the biopsy, clinical stage
and percent of biopsy
cores involved with cancer. These variables are outlined
below.
|
 |
|
 |
Contents of This Page
Faculty
Peter
Carroll, MD, MPH
Matthew Cooperberg, MD, MPH
Appointments & Location
Urologic
Oncology, UCSF Helen
Diller Family Comprehensive Cancer Center
1600 Divisadero Street, 3rd Floor
San Francisco, CA 94143-1711
Contact Number
For patient consultation please call us at 415/353-7171
Additional Information
CaPSURE
G-CEPS
The Genitourinary Cancer Epidemiology and Population
Science (G-CEPS) program encompasses all studies involving patients
or populations conducted by or in collaboration with Urology.
|
 |