These results suggest that the discordant patients had clinical outcomes that were more accurately selleck chemicals llc predicted by MammaPrint; therefore, 34% of Adjuvant! Online high-risk patients could have avoided chemotherapy because they had low-risk MammaPrint results. Similarly, 14% of patients who were categorized as low risk by Adjuvant! Online had high-risk profiles as determined by MammaPrint and might have benefited from additional treatment.41 Bueno-de-Masquita et al43 reported the results of 123 breast cancer patients with pT1-T2N0 disease, <55 years of age, who were followed up for a median of 5.8 years. In this dataset, 48% of patients had high-risk MammaPrint scores, which corresponded to a median 5-year OS of 82%, (95% CI �� 5%), with low-risk score patients having a corresponding median OS of 97% (��2%).

43 MammaPrint was shown to have a high negative predictive value for distant recurrence after adjuvant treatment (both endocrine and chemotherapy) in 100 postmenopausal breast cancer patients treated at the Massachusetts General Hospital.44 In this patient population, the 70-gene signature correctly identified 100% of women at low-risk for distant metastases at 5 years.44 Additional work revealed that MammaPrint has a strong prognostic value in patients with up to 3 positive lymph nodes.45 The 10-year distant metastasis-free survival was 91%, for the good prognosis-signature group (99 patients), and 76% for the poor prognosis-signature group (142 patients).

Further work by Mook et al45 demonstrated that MammaPrint can accurately select postmenopausal women at low-risk of breast cancer-related death within 5 years of diagnosis and can be used clinically to identify postmenopausal women who would benefit most from adjuvant chemotherapy.46 MammaPrint appears to be effective in classifying patients into either a low-risk (<10%) or high-risk of developing distant metastases. Corresponding hazard ratios for time to distant metastasis adjusted for clinical risk in patients with high-risk MammaPrint tumors in the first 5 years following curative treatment vary from 4.5 to 4.7.41 It is important to note that it is in these same years that chemotherapy exerts its maximal beneficial effect.47 Patients who received adjuvant treatment clearly show a lower risk of recurrence compared to untreated patients in this same 5-year period, whereas beyond this interval the difference in risk of recurrence stabilizes.

The predictive value of MammaPrint for chemotherapy benefit Entinostat in addition to endocrine therapy has been analyzed from pooled study series. In a study involving 541 patients who received either endocrine treatment (n = 315) or chemotherapy followed by endocrine treatment (n = 226), distant disease-free survival at 5 years was determined for MammaPrint high- and low-risk groups.