Molecular Evaluation of Breast Ductal Carcinoma in Situ with Oncotype DX DCIS

https://ajp.amjpathol.org/article/S0002-9440(18)30581-9/fulltext

"The score helps to identify a subset of women >50 years old with unifocal disease that carries <10% risk of any local recurrence after breast-conserving surgery alone. In this population, individual patients and physicians may consider omitting adjuvant radiotherapy."

"The final 12-gene panel for the Oncotype DX Breast DCIS Score includes seven cancer-related (Ki-67, AURKA/STK15, BIRC5/survivin, CCNB1, MYBL2, PGR, and GSTM1) and five reference genes (ACTB, GAPDH, RPLPO, GUS, and TFRC). The DCIS Score is scaled numerically from zero to 100 and classified into three risk prespecified categories: i) low risk (Oncotype DX DCIS Score <39); ii) intermediate risk (Oncotype DCIS DX Score = 39 to 54); and iii) high risk (Oncotype DX DCIS Score ≥55). The Oncotype DCIS DX Score was designed to quantify the 10-year risk of any ipsilateral breast event (local or invasive recurrence) after BCS for pure DCIS after BCS for pure DCIS without radiotherapy."

"A few studies on the correlation between the Oncotype DCIS Score and traditional histopathologic prognosticators were recently published. A single-institution study of 46 cases of pure DCIS....A low Oncotype DCIS Score was significantly associated with low nuclear grade, ERand PGR expression ≥90%, mitotic count ≤1, and absence of dense periductal inflammation. They found a significant association between high ERand PGR expression, low mitotic rate, and low Oncotype DCIS Score, as well as absence of dense periductal chronic inflammation. In this limited sample, all 13 cases with PR expression ≥90%, ≤1 mitotic figure, and absence of dense chronic inflammation around DCIS had a low score. Moreover, a low score was not observed in any case with at least two of the following: negative PGR expression, >1 mitotic figure, and/or presence of dense chronic inflammation....

Another single-institution study...included 37 patients with DCIS...low Oncotype DCIS Score was associated with low nuclear grade, absence of necrosis, high ER and PGR expression by immunohistochemistry, and a lower rate of adjuvant radiotherapy (P < 0.008). In this study, patient age, mitoses, DCIS size, final margin, DCIS cellularity, dense inflammation, and calcification were not significantly different between the low, intermediate, and high Oncotype DCIS Score groups. However, in approximately one-fifth of cases, Oncotype the DCIS Score was considered unexpected in relation to the histopathologic findings (ie, high nuclear grade with comedo necrosis and a low Oncotype DCIS Score) or hormone receptor discrepancies."

Nope, it's a completely different test. The Oncotype DCIS is looking at the genetic make-up of the DCIS cells. A genetic test that looks at BRCA and other genes a blood test that looks at the genes we are all born with, seeing if there are any irregularities (mutations) within any genes.

Genetic testing and advanced genomic testing https://www.cancercenter.com/diagnosing-cancer/gen...

"Genetic testing and genomic testing may sound similar, but they are very different procedures. Genetics refers to the genes a person is born with that are inherited from past generations. Genetic tests may help determine whether a person has inherited gene mutations that may increase the risk of cancer. Genomics refers to the molecular composition of a tumor."

I didn't get an OncotypeDX test at the time of my lumpectomy (Sep 2019), as it was felt to be obvious that I wouldn't need chemo and I was with an HMO. Now I am on medicare and just curious, if an Oncotype test be done now, 9 months later?

Since this thread is entitled "Questions about the DCIS Oncotype DX test", just for clarity, there are two different Oncotype tests for breast cancer patients.

The first is the Oncotype DX test, which, as windingshores mentioned, is used mainly to determine whether chemo will be recommended for those diagnosed with invasive breast cancer.

The second is the "Oncotype DX Breast DCIS", which is used to determine the need for radiation in patients who've had a lumpectomy with a diagnosis of Stage 0 DCIS. It is this second Oncotype test that was the initial subject of this thread, and it's important that the two tests not be confused for each other (which is difficult, given the similar names).