Feb 21, 2020 09:12PM Beesie wrote:Molecular Evaluation of Breast Ductal Carcinoma in Situ with Oncotype DX DCIS
"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."