Verzenio® (Abemaciclib)

Para consultar la información para prescribir completa de Verzenio® (Abemaciclib) de clic en el siguiente enlace: Información para prescribir

La información es proporcionada en respuesta a su solicitud, y puede contener datos relacionados a dosis, usos, formulaciones y poblaciones diferentes a la Información para Prescribir del producto. Consulte la Información para Prescribir en la liga que aparece arriba.

Abemaciclib: Ki-67 Diagnostic Test Information for Pathologists

Ki-67 is a nuclear marker used to assess cellular proliferation in breast cancer tumors .

MX_cFAQ_ABE080_KI67_DIAGNOSTIC_PATHOLOGISTS
MX_cFAQ_ABE080_KI67_DIAGNOSTIC_PATHOLOGISTS
es-MX

Background

Ki-67 is a nuclear marker present during all phases of the cell cycle, except the resting phase (G0), with peak levels of the marker occurring during mitosis. Ki-67 has been used to assess cellular proliferation in breast cancer tumor samples using IHC assays.1,2

Interpretation of Ki-67 assessments by IHC assays has previously lacked reproducibility across laboratories.3 Furthermore, no standardized procedure or cut-off definition existed prior to its prospective evaluation within the monarchE clinical trials, limiting its routine use in pathology.4

External Reproducibility Study

A study was completed to evaluate the external reproducibility of an analytically validated Ki-67 IHC assay developed for investigational use in breast cancer samples from patients participating in the abemaciclib adjuvant early breast cancer monarchE study.5

The reproducibility study was conducted in 2 parts. Part A assessed inter-site and intra-site reproducibility of Ki-67 staining and interpretation of 5 replicated sets of 30 FFPE breast carcinoma specimens performed at 3 external laboratories.5

Part B assessed inter-observer and intra-observer reproducibility with one pre-stained set of 60 FFPE breast carcinoma specimens.5

Reproducibility was measured using diagnostic endpoints of

  • “positive” if Ki-67-expressing tumor cells were >20%, and
  • “negative” if <20% of tumor cells stained with the antibody.5

Negative percent agreement, positive percent agreement, and overall percent agreement with 2-sided 95% confidence intervals were calculated. Acceptance criteria for all agreements required that the 2-sided 95% confidence intervals lower-bound values must be >85%.5

Results

The calculated lower bounds of the 95% confidence intervals were >85% for all parameters at the >20% cut-off. Acceptance criteria was met by

  • inter-site reproducibility across 3 sites,
  • intra-site/inter-day reproducibility across 5 days within 3 sites,
  • inter-observer reproducibility across 3 pathologists, and
  • intra-observer reproducibility across 3 reads by 3 pathologists.5

The study successfully demonstrated external reproducibility results at the >20% cut-off and support the use of this Ki-67 IHC assay to reproducibly detect Ki-67 in breast carcinomas.5

References

1Dowsett M, Nielsen TO, A'Hern R, et al. Assessment of Ki67 in breast cancer: recommendations from the International Ki67 in Breast Cancer working group. J Natl Cancer Inst. 2011;103(22):1656-1664. https://doi.org/10.1093/jnci/djr393

2Yerushalmi R, Woods R, Ravdin PM, et al. Ki67 in breast cancer: prognostic and predictive potential. Lancet Oncol. 2010;11(2):174-183. https://doi.org/10.1016/S1470-2045(09)70262-1

3Harris LN, Ismaila N, McShane LM, et al. Use of biomarkers to guide decisions on adjuvant systemic therapy for women with early-stage invasive breast cancer: American Society of Clinical Oncology Clinical Practice Guideline. J Clin Oncol. 2016;34(10):1134-1150. https://doi.org/10.1200/JCO.2015.65.2289

4Inwald EC, Klinkhammer-Schalke M, Hofstädter F, et al. Ki-67 is a prognostic parameter in breast cancer patients: results of a large population-based cohort of a cancer registry. Breast Cancer Res Treat. 2013;139(2):539-552. https://doi.org/10.1007/s10549-013-2560-8

5Polewski MD, Nielsen GB, Tabuena-Frolli ST, et al. External reproducibility of an analytically validated immunohistochemistry assay for detection of Ki-67 expression in breast carcinomas. Arch Pathol Lab Med. 2020;144(9s1):e2-e212. CAP20 Virtual abstract 400-68. http://dx.doi.org/10.5858/arpa.2020-0991-AB

Glossary

FFPE = formalin-fixed paraffin-embedded

IHC = immunohistochemistry

Fecha de la última revisión: 2020 M10 16


Contáctenos para saber más de la información Médica de Lilly

Contacto vía correo electrónico

Correo electrónico: infomed@lilly.com

Envíe su consulta

Escriba su consulta