Cancer Genomics - Genomics in predicting prognosis of cancer - Week 10 Flashcards
Genomics can be used to
predict prognosis of cancer
Breast cancer is the
third most common cause of UK cancer-related deaths.
Breast cancer survival depends on a number of factors including
stage of disease, tumour biology and treatment.
Breast cancer survival - early diagnosis
More than 90% of women diagnosed with early breast cancer survive for at least 5 years, and 78% survive for 10 years.
Breast cancer survival - late diagnosis
In contrast, only 13% of those diagnosed with advanced disease survive for more than 5 years. In this talk we will be focusing on early breast cancer.
Treatment for early stage breast cancer usually involves
surgery followed by adjuvant therapy of radiotherapy, chemotherapy, hormone therapy, biological therapy or a combination of these.
The side effects of these adjuvant therapies, particularly
chemotherapy can be particularly unpleasant so it is important to only give it to those patients that need it.
The decision whether to give adjuvant therapy is based on
clinical history, stage and grade of the disease, the likely course of the disease, molecular characteristics of the tumour and the patients preferences.
what is PREDICT?
online prognostic and treatment benefit calculator, is the most widely used tool in the NHS in England to calculate risk of recurrence in patients who have had early breast cancer.
the PREDICT tool looks at
size and type of the cancer at diagnosis, whether the cancer has spread to involve lymph nodes, and whether or not the cancer expresses markers such as the oestrogen receptor (ER), HER2 and KI67 to predict average survival and how much benefit might be gained on average from different treatment options (shown in the bottom picture).
PREDICT and other such computer algorithms produce
good estimates of survival and recurrence, but they cannot say whether an individual patient will survive their cancer or not.
Limitation of PREDICT
It can only provide the average survival rate for people in the past of a similar age and with similar cancers so do have limitations.
For this reason a number of tumour profiling tests have been developed that look at
the activity of a range of genes in tumour sample to help decision making about whether adjuvant chemotherapies required to ensure patients are not being under or over treated.
Examples of some of the profiling tests:
EndoPRedict (Myriad Genetics)
MammaPrint (Agendia)
Oncotype DX Breast recurrence Score (genomic Health)
Prosigna (NanoString Technologies)
IHC4 and IHC4+C
EndoPRedict (Myriad Genetics)
Measure the expression of 12 genes: 3 proliferation-associated genes, 5 hormone recetpro-associated genes, 3 reference (normalisation) genes and 1 control gene