average wait time for oncotype results

Hi JuniperCat:

Mustlovepoodles will eventually reply that no, the OncotypeDX test did not reveal the mutations in PALB2 or CHEK2. She would have had to have separate genetic testing done to determine mutation status. OncotypeDX does not test those genes.

OncotypeDX looks at 16 cancer-related test genes (and 5 reference genes) and determines the level of "gene expression", meaning how much are the genes being used by the tumor cells. Based on what is known about patterns of gene expression of these genes in tumor cells, and how such patterns correlate with low, intermediate or high risk, the test provides guidance about chemotherapy decisions.

It is important to understand that the OncotypeDX test is NOT a genetic test in that it does not provide any information about the presence or absence of genetic mutations in the test genes (or any other genes). If one is concerned about having a genetic predisposition to cancer based on factors like family history of breast cancer or other cancers, personal history of breast cancer, early age at presentation, etc., please request a referral to Genetic Counselor who can advise you if you are a candidate for genetic testing.

Here is an explanation of the two kinds of tests, highlighting some ways that they differ:

"Genetic testing" is performed on a sample containing normal cells (e.g., blood) to determine if you carry a mutation in your DNA that confers a genetic pre-disposition to cancer. By using normal cells, the implication is that all your cells, including germ cells (oocytes (F) or sperm (M)), also contain the mutation and the mutation is heritable. The methodology used entails extensive genomic DNA sequencing and may also include an assessment of certain gene rearrangements.

In contrast, Oncotype DX for "invasive" disease is performed on a sample of tumor cells and assesses the levels of gene expression (not the DNA sequence) from 16 cancer-related genes and five reference genes, meaning it looks at how much the genes are being used in the tumor cell. The methodology used is quantitative "RT-PCR" (reverse-transcriptase polymerase chain reaction) which looks at transcription (how much mRNA is being produced from each test gene).

If you are interested in the particular genes tested for expression, a list can be found here:

http://breast-cancer.oncotypedx.com/en-US/Professi...

BarredOwl

Hi JuniperCat:

While I understand what the tests are and how they are done (because I have some biology background), the clinical implications, particularly in the intermediate range, are a harder question! Hopefully, once you have a chance to discuss your Oncotype score with your MO, you will have a clearer picture of what your score means, and the weight of any other relevant pathological findings and presentation (e.g., age).

By the way, please make sure you get a copy of the original Oncotype report for your records if you do not already have one. You may want to ask your MO to review the report content with you, so you understand all of the information provided.

The following is some information about the MammaPrint test. Be sure to obtain current professional advice from your medical oncologist and confirm any information below.

Here is some information from the National Comprehensive Cancer Network (NCCN) guidelines for breast cancer (Professional Version, 1.2016) about MammaPrint (emphasis added by me):

"MammaPrint assay uses microarray technology to analyze a 70-gene expression profile from breast tumor tissue (formalin-fixed, paraffin-embedded fresh or frozen breast tumor tissue) to help identify patients with early-stage breast cancer likely to develop distant metastases.(242-248) MammaPrint is approved by the FDA to assist in assignment of women with ER-positive or ER-negative breast cancer into a high versus low risk for recurrence, but not for predicting benefit from adjuvant systemic therapy. MammaPrint is approved by the FDA and assigns women of all ages with ER-positive or ER-negative breast cancer as having high versus low risk for recurrence. The prospective RASTER study reported that breast cancer patients classified by MammaPrint as low risk (of whom 85% did not receive adjuvant chemotherapy) had an overall 97% distant recurrence-free interval at five years.(249)" [Note: 15% received chemo]

The MammaPrint test has not been incorporated into the NCCN treatment guidelines, although they do discuss its use. That may simply reflect that the Oncotype test is better validated, and can provide more information in a single test. In particular, the NCCN guidelines indicate:

"[B]ased on the currently available data, the panel believes that the 21-gene assay [OncotypeDX for invasive disease] has been best-validated for its use as a prognostic test as well as in predicting who is most likely to respond to systemic chemotherapy."

It seems like in the NCCN view, the MammaPrint test can currently be used to assess risk of distant recurrence.

My understanding is that patients are classified as "high risk" or "low risk". However, the MammaPrint results do not provide individualized risk, but only provide the average risk associated with the high risk cohort or the average risk associated with the low risk cohort.

"The MammaPrint® FFPE result is indicated for use by physicians as a prognostic marker only, along with other clinico-pathological factors." In other words, MammaPrint is not recommended as a stand-alone (does not dictate decisions), but is used in conjunction with other factors.

In some cases, this type of information might help inform or supplement the risk/benefit analysis. In fact, some members here, including Stage I, node negative patients, have received the MammaPrint test after they got an intermediate score by OncotypeDX. So, please do not hesitate to ask your MO about the MammaPrint test, what kind of information it can provide, and whether the information may be useful in your case.

More information can be found at Agendia's web site:

http://www.agendia.com/patient/breast/

All the best as you work to come to a decision that is right for you.

BarredOwl

Major thanks to Barred Owl for her accurate description of both the Oncotype DX test and genetic testing. Due to my family history of lung, colon, breast, and pancreatic cancer, my genetics counselor recommended that I have the 32-gene assay test, rather than just testing for the BRCA genes. So glad I did, because the simpler test would not have revealed the two much rarer genes.

My MO recommended chemo for 3 reasons: Oncotype 23, gene mutations, and PR- status. She also advised BMX, which will happen later in Jan, and ovary removal or total hysterectomy.