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Five year survival from breast cancer is lower in deprived areas, says UK report

BMJ 2011; 342 doi: (Published 13 June 2011) Cite this as: BMJ 2011;342:d3661

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Breast cancer outcome and social class

Breast cancer outcomes are closely related to social class and
deprivation. Initially it was assumed that this was simply due to late
presentation. Although it is true that more socially deprived and ill
educated women present with advanced disease than their more fortunate
sisters, if matched stage for stage, their prognosis is still compromised. [1] The issue is therefore more complicated than at face value. Next it
was thought that these differential outcomes might be related to access to
health care. This might indeed be true for the 50 million uninsured in the
USA but can hardly be true for the UK where the NHS mandates equal rapid
access to specialist breast clinics. However even in the USA correcting
for access to health care providers cannot explain the differences. [2]

Next we have to consider the ethnicity of the socially deprived. In many
parts of the USA and the UK, social deprivation is closely linked to
ethnicity and some of these ethnic groups develop breast cancers that are
biologically different than those of the majority of the Caucasian
population. For example black Afro-Caribbean women develop the disease at
an earlier age and with a more aggressive phenotype [3] whilst many women
from the Indian sub-continent or the Arabian Gulf come from families where
consanguineous marriages are common and also develop breast cancer at an
early age with features suggestive of a genetic predisposition. [4] Yet a
fourth possibility has been suggested that women of low social class fail
to comply with their medication are more likely to abandon their course of
tamoxifen than a better educated class. [5] Finally new data from Georgios
Lyratzopoulos and colleagues [6] describes a narrowing of the margins in
the absolute differences in 5 year survival for breast cancer between the
more and less affluent sections of society over the last 32 years that are
attributed to a slow but steady uptake of improved modalities of therapy
e.g. tamoxifen, over this period.

When one considers the impact of screening on the outcomes described in
terms of one or 5-year survival based on social class the subject becomes
more problematic. [7] It is tiresome to constantly have to remind the
proponents of screening of the biases involved in using "survival"
outcomes rather than mortality in assessing the impact of this public
health intervention. These are lead-time bias (extending the period of
observation to the left) that at its extreme is linked to the "over-diagnosis" of latent disease when the lead- time is in fact the natural
duration of that woman's life. Length bias whereby interval cancers, the
aggressive fast growing tumours, are ignored whilst only counting the
slower growing tumours that tend to wait for the screener to come along
before diagnosis. Finally there is Attendance bias, which recognises the
fact that socially deprived women are more likely to ignore the invitation
to be screened and as described above start off with a poorer chance of
cure. In the NCIN report highlighted in this discussion [7] the measured
outcomes are stratified by social class so in theory at least; the third
bias can be excluded. So what are we left with? If we cajole and coerce
poor, ill educated and socially deprived women into screening then they
have the same chance of the over-diagnosis and over-treatment of breast
cancer as their more fortunate sisters, whilst also enjoying the extended
period of observation of their slow growing disease resulting from lead
time bias. Now there's progress for you. All that's left is to persuade
them to carry on taking their tablets.


1. Kogevinas M, Porta M. Socioeconomic differences in cancer survival: a
review of the evidence. IARC Sci Publ. 1997;(138):177-206.

2. Retsky MW, Demicheli R, Gukas ID, Hrushesky WJ. Enhanced surgery-
induced angiogenesis among premenopausal women might partially explain
excess breast cancer mortality of blacks compared to whites: an
hypothesis. Int J Surg. 2007 Oct;5(5):300-4.

3. Demicheli R, Retsky MW, Hrushesky WJ, Baum M, Gukas ID, Jatoi I. Racial
disparities in breast cancer outcome: insights into host-tumor
interactions. Cancer. 2007 Sep 17.

4. Gukas I, Jatoi I, Demicheli R, Retsky M, Hrushesky W, Baum M. Complex interplay between race and breast cancer: Should this affect
breast cancer diagnostic and therapeutic strategies? Current Medical Literature 21:1-8, 2009.

5. Kimmick G, Anderson R, Camacho F, Bhosle M, Hwang W, Balkrishnan
R. Adjuvant hormonal therapy use among insured, low-income women with
breast cancer. J Clin Oncol. 2009 Jul 20;27(21):3445-51

6. Lyratzopoulos G, Barbiere JM, Rachet B, Baum M, Thompson MR,
Coleman MP. Changes over time in socioeconomic inequalities in breast and
rectal cancer survival in England and Wales over a 32-year period (1973-
2004): the potential role of health care; In press; Annals of Oncology

7. NCIN Second all breast cancer report, NHS cancer screening
programmes 2011:

Competing interests: No competing interests

16 June 2011
Michael Baum
Professor emeritus of Surgery