How to interpret an ER/PR report in Breast Cancer

All human cells have some receptors present on their surface. Normal human breast cells respond to the female hormones i.e. estrogen & progesterone, therefore they carry estrogen (ER) and progesterone receptors (PR).

Like healthy breast cells, majority of the breast cancer cells also possess ER & PR receptors. Every breast cancer is different and knowing the fact whether the breast cancer is positive for ER, PR receptors, has an important bearing on the management of the patient’s disease. If a patient’s breast cancer shows these receptors, then they can be subjected to hormonal therapy, which can control the tumor growth by blocking these receptors.

fa7b1b4c02d39fe1ebf89819c8f3902c

Sometimes during the course of treatment, the breast cancer cells which are ER, PR positive initially can lose the receptors and become ER, PR negative and they stop responding hormonal therapy. Rarely, the opposite of this is true as well.

Considering this background, it is important that a lady knows how to interpret the hormone receptor status report & understand the implications in breast cancer management based on this report.

Most laboratories used a special method to stain these receptors known as IHC (immunohisto-chemistry). Each lab has their own way of analyzing these receptors, which is why I am covering the most commonly used methods:

  • A percentage that tells you how many cells out of 100 stain positive for hormone receptors.You will see a number between 0% (none have receptors) and 100% (all have receptors).

 

  • Allred score between 0 and 8. This system looks at what percentage of cells test positive for hormone receptors along with the intensity of staining. This information is then combined to score the sample on a scale from 0 to 8. The higher the score, the more receptors were found and the easier they were to see in the sample.

 

  • Positive or negative report

 

Different labs have different cutoff points for calling the cancer either positive or negative. For example, if less than 10% of your cells — or fewer than 1 in 10 — stain positive, one lab might call this a negative result. Another lab might consider this positive, even though it is a low result. Some studies have shown that even cancers with low numbers of hormone receptors may respond to hormonal therapy. A score of “0” means that the patient is hormone receptor negative and will not benefit from hormonal therapy.

Some points to remember

Once the report is declared, your oncologist with discuss your hormone receptor report with you and these are some points, which will help you in understanding your report:

  • ER+/PR+:Majority (65%) of the Breast cancers are ER, PR positive and these patients are candidates for hormonal therapy.
  • ER positive but PR negative OR ER negative but PR positive:Around 10-13% patients fall in these two categories. Despite one of the receptors being negative, these patients are still candidates for hormonal therapy.
  • ER-/PR-:Around 20% patients fall in this category and they are not considered to be candidates for hormonal therapy.

 

If your test result is positive for ER/ PR, you should discuss the role of hormonal therapy with your oncologists. Hormonal therapy helps in preventing the recurrence of disease in patients with localized breast cancer whereas it keeps the tumor growth under control in patients with metastatic breast carcinoma.

 

Article by:

Dr. Rohan Khandelwal

Consultant, Breast Onco-Surgeon

W Pratiksha Hospital,

Gurgaon, India

Advertisements

Endopredict vs Oncotype Dx for Breast Cancer

A new test, called EndoPredict, can predict the risk of a woman’s breast cancer spreading within 10 years of diagnosis more accurately than the current Oncotype Dx test. Also, research found that the results can be made available more quickly.
 
A study, published in the Journal of the National Cancer Institute, compared EndoPredict with Oncotype DX. Both tests can predict whether breast cancer will spread in women with oestrogen receptor positive, HER2 negative (ER+/HER2-) disease. This is a sub-type of breast cancer that accounts for about two-thirds of all cases.
 
The new EndoPredict test analyses eight different genes found in a sample of a patient’s tumour. This information, as well as the size of the patient’s tumour and their nodal status – whether the cancer has spread from the breast to their lymph nodes – are then used to determine the patient’s risk of their breast cancer spreading in the next 10 years.
 
An ‘EPclin’ score categorises patients into low- and high-risk groups. Patients placed in the high-risk group would be recommended to have chemotherapy, but those in the low-risk group could be spared this treatment – and the debilitating side effects associated with it.
 
In the study it was found that EndoPredict was more accurate and the results were available faster as compared to the conventional Oncotype Dx test.
 
Points to remember:
1. EndoPredict is meant for early breast cancers which are ER, PR positive (same as Oncotype Dx)
2. It analyses 8 genes as compared to 21 in Onctoype Dx