The use of pre-diluted VENTANA HER2 (4B5) Rabbit Monoclonal Antibody RxDx1, in combination with the fully automated BenchMark IHC/ISH slide staining instrument, standardizes all IHC processes from baking through staining, and reduces the possibility of human error. It also minimizes inherent variability resulting from individual reagent dilution and other processes found in manual and semi-automated IHC methods.
The Roche HER2 (4B5) clone* empowers you to:
Building on the same proven technology trusted for consistently achieving higher overall proficiency scores compared to other clones2, Roche’s widely adopted assay* is now approved to identify HER2-low breast cancer patients, helping to match even more women with highly effective, personalised therapies. It is the first and only test approved to identify breast cancer patients with HER2-low status who may be eligible for targeted treatment with ENHERTU.1
* PATHWAY/VENTANA anti-HER2/neu (4B5) Rabbit Monoclonal Primary Antibody products
The Roche HER2 (4B5) clone* has shown the most consistent performance and superior quality when compared to other on-market HER2 clones.2
* Based on data for PATHWAY® anti-HER2/neu (4B5) Rabbit Monoclonal Primary Antibody and VENTANA anti-HER2/neu (4B5) Rabbit Monoclonal Primary Antibody products.
For breast carcinoma specimens when using the staining procedure for all HER2 assessment including potential HER2-low assessment
| Staining pattern | HER2 (4B5) score (report to treating physician) | Recommended reporting status | Therapy* |
|---|---|---|---|
| No membrane staining is observed OR Faint, partial staining of the membrane in 10% or less of the cancer cells** |
0 | HER2-negative | None |
| Faint, partial staining of the membrane in > 10% of the cancer cells** | 1+ | HER2-low expression | ENHERTU (trastuzumab deruxtecan) |
| Weak to moderate complete staining of the membrane in > 10% of the cancer cells** | 2+*** Reflex test: HER2 non-amplified |
HER2-low expression |
|
| 2+*** Reflex test: HER2 amplified |
HER2-positive/overexpression | HERCEPTIN (trastuzumab) KADCYLA (trastuzumab emtansine) PERJETA (pertuzumab) |
|
| Intense complete staining of the membrane in > 10% of the cancer cells | 3+ | HER2-positive/overexpression |
For breast carcinoma specimens when using the alternative staining procedure intended for use in assessing HER2-positivity and not in assessing HER2-low expression
| Staining pattern | HER2 (4B5) score (report to treating physician) | Recommended reporting status | Therapy* |
|---|---|---|---|
| No membrane staining is observed OR Faint, partial staining of the membrane in 10% or less of the cancer cells |
0 | HER2-negative | None |
| Faint, partial staining of the membrane in > 10% of the cancer cells | 1+ | HER2-negative | |
| Weak to moderate complete staining of the membrane in > 10% of the cancer cells | 2+*** Reflex test: HER2 non-amplified |
HER2-negative |
|
| 2+*** Reflex test: HER2 amplified |
HER2-positive/overexpression | HERCEPTIN (trastuzumab) KADCYLA (trastuzumab emtansine) PERJETA (pertuzumab) |
|
| Intense complete staining of the membrane in > 10% of the cancer cells | 3+ | HER2-positive/overexpression |
For gastric carcinoma specimens
| Staining pattern - resection specimen | HER2 (4B5) score (report to treating physician) | Recommended reporting status | Therapy* |
|---|---|---|---|
| No reactivity or membranous reactivity in < 10% of tumour cells | No reactivity or membranous reactivity in any tumour cell | 0 | Negative |
| Faint/barely perceptible membranous reactivity in ≥ 10% of tumour cells; cells are reactive only in part of their membrane | Tumour cell cluster† with a faint/barely perceptible membranous reactivity irrespective of percentage of tumour cells stained | 1+ | Negative |
| Weak to moderate complete, basolateral or lateral membranous reactivity in ≥ 10% of tumour cells | Tumour cell cluster† with a weak to moderate complete, basolateral or lateral membranous reactivity irrespective of percentage of tumour cells stained | 2+ |
Equivocal†† |
| Strong complete, basolateral or lateral membranous reactivity in ≥ 10% of tumour cells | Tumour cell cluster† with a strong complete, basolateral or lateral membranous reactivity irrespective of percentage of tumour cells stained | 3+ | Positive |
* Refers to HER2-targeted therapies
** Recommend re-reading by a second pathologist for cases with “faint, partial staining of the membrane” and % TC near the threshold of 10%, when the range of % TC is between 5%-25%
*** Recommend reflex test to assess gene amplification per ASCO/CAP guidance
† ≥ 5 cohesive cells
†† Recommend reflex to ISH
References
