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Diagnosing and treating cancer cost £6bn per year, a disease that will affect one in three of us during our lifetime. Despite year-on-year improvements in cancer treatment the UK still trails other OECD counties for cancer outcomes. Better prevention, screening and early detection were identified in the 2011 NHS Cancer Outcome Strategy as ways to reduce the growth in incidence of cancer and improve one and five year survival. from diagnosis. Bowel cancer detection and treatment has improved but still lags when compared with other developed nations. A major program of bowel cancer screening has been rolled out in England with the aim of detecting and removing pre-cancerous polyps. A national advertising campaign has been used to raise awareness of cancer symptoms to encourage patients not to delay in contacting their doctor when they have “blood in their poo”. A hybrid model has been developed to link through from the early patient behavioural aspects of cancer detection through to outcomes. The hybrid approaches uses a discrete event simulation to represent the pre-cancerous stages through to initial contact points with the NHS and then onto to diagnosis and staging by the multi multidisciplinary teams (MDT). From the stage of diagnosis a probabilistic pathways model was used to predict annual costs and mortality for up to 10 years after initial diagnosis. This approach permitted developing a total lifetime cost measure for patients with a cancer diagnosis and the ability to test out how this might change with different policy options. Early modeling results have assisted the better understanding of the medium and long term implications of policies on bowel cancer and have helped set priorities to improve outcomes
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Modelling your way out of the poo
Forecasting costs and outcomes of bowel cancer
David Halsall, John Osmond and Laura Bown
NHS England Analytical Services
So what is the problem with bowel cancer?
• 325,000 people diagnosed with cancer in the UK in 2010, half of them will die of the disease. A third of people will develop cancer in their lifetime
• There has been a 35% increase in incidence since 1970s, largely related to lifestyle and improvements in other conditions e.g. heart disease.
• Bowel cancer survival is poor compared to other countries which is largely down to late presentation.
• Current polices to address this poor performance are based around screening and better awareness.
• We want to model how current policies will feed through to the better outcomes and estimate how much it will cost over a 5 -10 year period.
Background to the problem
One in three of us will get cancer in our lifetime
10,000
20,000
30,000
40,000
50,000
60,000
0-19 20-64 65-74 75+
Ne
w c
as
es
of
can
ce
r
New cases of cancer 2000 & 2010 by age
Breast 15% Lung 13%
Colorectum 13%
Prostate 13%
One in three people can expect to have a
cancer diagnosis at some time in their life.
This cancer incidence rate is average for
north Europe, higher than western Europe
and lower than the US and Canada
For many cancers having a healthy lifestyle
can reduce the risk of getting the disease.
Tobacco, being over weight, low fruit & veg & alcohol
are known risk factors for cancer. Most of lung
cancers and half of bowel cancers could be
preventable by lifestyle
Male =
Female =
2000
2010
Lifestyle choices and improved treatment for
cardiovascular conditions is leading to an increase in
the incidence of cancer. Soon over 2 million people will
have had a cancer diagnosis.
Four cancer types are responsible for half of new
cases reported each year. Leukaemia, brain,
melanoma, ovary, uterus lymphoma & pancreas
make up the next most frequent sites. There are a
further 20 sites of rarer cancers.
Background of cancer
Cancer survival is improving but England is still lagging by
international comparisons
Background of cancer
Five year cancer survival
Over the past 30 years the chances of surviving five
years after diagnosis has doubled for breast and bowel
cancer. Some cancers, such as lung, are particularly
hard to treat and progress has been much slower.
Colorectal cancer, five-year relative
survival rate by sex, 2004-09 (or nearest period)
Despite this improvement England and the UK have
lagged behind comparator countries but current
strategies aim to halve the difference between England
and the average of Australia, New Zealand Canada.
Health at a Glance 2011: OECD Indicators
Biology of cancer – slow start & explosive finish
Stage 1 (Duke A)
Stage 4 (Duke D)
Stage 3 (Duke C)
Stage 2 (Duke B)
Cut off point for curative
treatment
Symptoms and the first
opportunity for imaging
diagnosis
Generic (Bowel)
Background of cancer
If you die of cancer
you will have around
1kg of cancer cells in
your body
Why is cancer survival poor in the UK? Why is survival poor in the UK?
Why is survival poor in the UK?
• The excess of very early deaths in the UK suggests late diagnosis plays a major part of the story
• Around 25% of cancers are diagnosed as emergency admission in A&E. Many of these patients may only live for a couple of weeks after first diagnosis
• It is likely that late presentation by patients, late investigation and/or onward referral and suboptimal primary treatment all play a part in the explanation. But the sooner treatment is started the better the outcome
•
Why are UK cancer outcomes poor
Colon cancer: all-ages, one-year net
survival by stage of first diganosis A B C D
98.3% 90.8% 78.1% 36.7% Colon cancer: all-ages, one-year net survival* (NS, %) by stage at diagnosis ECRIC cancer registry
Patients diagnosed during 2006 in the cancer registries included in the ICBP analyses
Cancer screening can spot cancers before symptoms
become apparent.
• Breast and cervical cancer have well established screening programmes.
• Lung cancer screening may be beneficial for those who smoke
• Bowel cancer screening was first piloted in 2000 and has rolled out in waves and now offers screening every two years to all men and women aged 60 to 69.
• The NHS is now also rolling out bowel scope screening to all men and women aged 55 to remove polyps before they become cancerous
• There are no other major cancers which are routinely screened for.
Cancer screening
An abnormal bowel cancer screening test
can lead to the detection of pre-cancerous polyps or
cancer at an earlier stage
8
Dukes stage at
diagnosis
Screen-
detected Non-
participant % %
A 27.9 10.4 B 22.7 23.5 C 25.7 26.7 D 6.3 21.0
Unknown 17.4 18.4
Removal of pre-cancerous polyps
can lead to a reduction of
cancer incidence
Crude 1 year survival 96% 77% Morris et at BJC (2012) 107 757-764
Promptly diagnosing cancer is key to good
outcomes in non-screened patients
Delays in the patient presenting with symptoms • Most patients present to their GP with symptoms – and most present quite
quickly
• Some patients present symptoms late or never. These patients frequently
report that they were unaware their symptoms could be serious.
• People in the UK (rather than patients) frequently report that they would be
worried about wasting their GPs time.
Delays in diagnosis • Most patients with cancer are referred promptly by GPs (one or two visits only)
down the rapid access 2 week wait route.
• Some are only referred after multiple visits.
• There are large variations in use of direct access diagnostic tests, such as
chest x-ray between general practices.
• There are large variations in the use (and accuracy of use) of urgent referral
2WW routes
Why are UK cancer outcomes poor
The Be Clear on Cancer advertising
campaign targets those with symptoms
Early detection of cancer
The lifetime cost of bowel cancer is heavily dependent on
complications and the treatment of secondary cancers
11 Stage of diagnosis D C B A
Produced by Monitor Company Group, L.P.
for Macmillan cancer support 2012
Cost of treating bowel cancer
The aim is to increase the proportion of cancers diagnosed at stages A & B
which will improve outcomes but may not reduce costs in the short term
Modelling the problem
Stage of
diagnosis
at
MDT*
0%
10%
20%
30%
DukeA
DukeB
DukeC
DukeD
Colon cancer 2006 ECRIC
Duke B
Duke C
Duke D
Survival – 1 to 5 years
Duke A 12K
Total costs
22K
24K
10K
Screening
Population
Emergency
GP
2WW
Other
Modelled with discrete
event simulation
Modelled with Excel based
Stocks and Flow simulation
* Multi-disciplinary team
Part 1: Pre First MDT
Symptoms
Screening
Cancer Symptoms
A&E
1%
96% GP
Death
Death
3%
MDT Routine
1%
76%
23%
Urgent
Modelling the problem
National Cancer Intelligence Network, Routes to Diagnosis
What is microsimulation?
Example: Pharmacy
Arrival Queue Served Exit
Microsimulation models operate at individual unit level, e.g
vehicles on a road, suitcases in an airport. NHS patients can
be modelled in the same way.
Each unit has its own unique set of characteristics. Rules and
probabilities control the movement of these units through the
model. Rules and probabilities can then be changed to assess
the impact of policy interventions.
Clock
Discrete
Continuous
Modelling the problem
The microsimulation model The model is split into two parts – a microsimulation of the pathway up until
first MDT which gives results of stage of diagnosis. These results are then
linked to costs and survival data
Modelling the problem
Post first MDT treatment pathway
Symptoms
Stage A
MDT
Stage C
Stage B
Stage D
Radio-
Therapy
Chemo-
Therapy
Chemo-
Therapy
Minor
Surgery
Major
Surgery
Modelling the problem
1 – 5 year survival treatment with curative intent treatment with palliative intent
With in the modelling solution it has been assumed that
cancer survival will continue to improve independent of
funding
17
0
20
40
60
80
100
1971-1975 1976-1980 1981-1985 1986-1990 1991-1995 1996-2000 2001-2005 2006-2010 2011-2015 2016-2020 2021-2025
Per
cen
tage
of
case
s su
rvei
ng
on
e ye
ar
Probability of surviving one year by Duke stage used in model
Dukes D
Dukes C
Dukes A
Dukes C
Modelling the problem
Assumed probability living more than 1 year by cancer stage over time.
The Baseline case shows costs and the number of
in-year deaths both rising
This shows in the baseline
case in-year deaths from
symptom presentations
rising but at a slower
rate than new cases or cost
Dukes A Dukes B Dukes C Dukes D
New cases died New cases died New cases died New cases died
2013 2,995 488 7,336 1,180 7,346 1,716 5,309 3,650
2018 3,252 469 7,967 1,140 7,979 1,678 5,766 3,980
2023 3,510 403 8,599 1,049 8,611 1,716 6,222 4,276
Base line symptom based presentation
in-year cost (£m) New PC cases Died EME/unstaged
2013 22,986 7,033 7,462 338
2018 24,964 7,267 8,104 364
2023 26,942 7,444 8,746 389
250
300
350
400
450
500
0
5,000
10,000
15,000
20,000
25,000
30,000
2013 2018 2023
Baseline symptom based bowel cancer model output
New PC cases
Died in year
Costs
Results
0%
10%
20%
30%
Baseline stage of diagnosis
The model can predict what will happen over time if we
stage shift the distribution of first diagnosis from D to C
Results
live "saved" Cost (£M)
New cases died New cases died New cases died New cases died
2013 0 0 0 0 0 0 0 0 0
2018 0 0 0 0 500 86 -500 -325 -238 1
2023 0 0 0 0 1,000 178 -1,000 -664 -486 2
Dukes A Dukes B Dukes C Dukes D
Number of additional cases
above baseline. An additional
100/year cases are shifted
down one stage from Duke’s
D to C by 2023.
This will save 484 lives at an
additional cost of £2m / year
above baseline.
Stage of diagnosis
Assume 100 patients a year
Are shifted from D to C over 10 years
The model can predict what will happen over time if we shift
100 patients from each stage down by one stage.
Results
Number of additional cases
above baseline. 100/year
cases are shifted down one
Stage from Duke’s D to C to
B to A by 2023.
This will save 664 lives at an
additional cost of £1m / year
Above baseline .
live "saved" Cost (£M)
New cases died New cases died New cases died New cases died
2013 0 0 0 0 0 0 0 0 0
2018 500 35 0 0 0 0 -500 -325 -325 0
2023 1,000 83 0 0 0 0 -1,000 -664 -664 1
Dukes A Dukes B Dukes C Dukes D
Assume 100 patients a year are shifted D >C>B>A
0%
5%
10%
15%
20%
25%
30%
Duke A Duke B Duke C Duke D Unstaged
Baseline
100/year shift up
Baseline 10% 24% 24% 17% 25%
Shifted 13% 24% 24% 15% 25%
Net change over baseline
Summary and Next Steps
• Coarse modelling to demonstrate principle.
• Benefit: 200/300 lives saved per year via earlier diagnosis
by 2018
• 6% of the 5000 lives saved per year required across all
cancers in mortality call to action.
• Cost: Small increase of £1m/£2m per year
• Add appropriate level of detail and repeat in microsimulation.
Questions?
