On 2014 Nov 20, Neven Patrick commented:

Looks like estrogen removal reduced the proliferation significantly and probably the tumor has high ER mRNA score and very sensitive to estrogen deprivation. My thought is to regard this tumor as luminal A. Also important would be to check the probability of the class assignment by PAM50. Some cases surely will have lower probability than others and this case might be one of those. Because I presume single case PAM50 algorithm based on distance from centroid of model cases of intrinsic subtype will be forcing the class assignment for the cases which in the clustering would be gray zone cases. Does Prosigna report provide such QC measure? Soon Paik

Truly fascinating (and not so simple) questions! To my knowledge this has not been studied, and I agree that removal of estrogen could potentially alter the proliferative rate of the tumor (and proliferation is a dominant aspect of most MGS to date). For this patient I would base treatment on the higher risk result. Kathy Albain

If one measures Ki67 on the core it will be higher because pt is on E but if you measure it again 2 wks later on the surgical specimen it will be lower and won't agree with that done on the core. I would be surprised if that is not true. C.Kent Osborne

Just saw a patient with an ER+ cancer, ki67 30% on core biopsy. Stopped HRT. Had surgery for T2N0 IDC and oncotype 14. Oncologist recommended chemo due to Ki67. Repeated ki67 on surgical sample and it was less than 5%. There is clearly an education opportunity here. Presumably the lower ki67 after stopping HRT is predicative of outcome and impact of hormone therapy. Interesting.<br> Hope S. Rugo

On 2014 Nov 20, Neven Patrick commented:

Looks like estrogen removal reduced the proliferation significantly and probably the tumor has high ER mRNA score and very sensitive to estrogen deprivation. My thought is to regard this tumor as luminal A. Also important would be to check the probability of the class assignment by PAM50. Some cases surely will have lower probability than others and this case might be one of those. Because I presume single case PAM50 algorithm based on distance from centroid of model cases of intrinsic subtype will be forcing the class assignment for the cases which in the clustering would be gray zone cases. Does Prosigna report provide such QC measure? Soon Paik

Truly fascinating (and not so simple) questions! To my knowledge this has not been studied, and I agree that removal of estrogen could potentially alter the proliferative rate of the tumor (and proliferation is a dominant aspect of most MGS to date). For this patient I would base treatment on the higher risk result. Kathy Albain

If one measures Ki67 on the core it will be higher because pt is on E but if you measure it again 2 wks later on the surgical specimen it will be lower and won't agree with that done on the core. I would be surprised if that is not true. C.Kent Osborne

Just saw a patient with an ER+ cancer, ki67 30% on core biopsy. Stopped HRT. Had surgery for T2N0 IDC and oncotype 14. Oncologist recommended chemo due to Ki67. Repeated ki67 on surgical sample and it was less than 5%. There is clearly an education opportunity here. Presumably the lower ki67 after stopping HRT is predicative of outcome and impact of hormone therapy. Interesting.<br> Hope S. Rugo