Please clarify HER2 result

never saw it written like that...however, 0 or +1 is negative. A +2 means more testing is necessaryto determine if it is negative (0, +1). positive is +3

If the HER2 testing methodology was by validated immunohistochemistry ("IHC"), the result should be one of the following:

0 ("negative") OR

1+ ("negative") OR

2+ ("equivocal") OR

3+ ("positive")

The conclusion "not overexpressed" with reference to both "1+" and "3+" is ambiguous and requires review and clarification. This is because "1+" may be described as "not overexpressed" ("negative"), but 3+ would be described as "overexpressed" ("positive").

(Sometimes tumors are "heterogeneous" with areas having differing HER2 statuses. However, in such case, the presence of a HER2-positive area by IHC (3+) should be expressly indicated in the report by "overexpressed" or more preferably "positive" per guidelines.)

Please contact your surgeon at this time to point out this ambiguity. The pathologist should be asked to review this matter, and if indicated, provide clarification or a corrected pathology report.

HER2 status sometimes has implications for whether a surgery-first treatment plan is recommended, or whether consideration would be given to administration of chemotherapy plus HER2-targeted therapy (if HER2-positive) before surgery ("neoadjuvant therapy").

BarredOwl

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[[[ EDIT (03 June 2018): Please see also this 2018 ASCO Focused Guideline Update for HER2 testing:

Wolff (2018): "Human Epidermal Growth Factor Receptor 2 Testing in Breast Cancer: American Society of Clinical Oncology/College of American Pathologists Clinical Practice Guideline Focused Update"

http://ascopubs.org/doi/pdf/10.1200/JCO.2018.77.8738 ]]]

Wolff (2013): "Recommendations for Human Epidermal Growth Factor Receptor 2 Testing in Breast Cancer: American Society of Clinical Oncology/College of American Pathologists Clinical Practice Guideline Update"

http://ascopubs.org/doi/pdf/10.1200/jco.2013.50.9984

For additional details and correspondence, see also, "Related Content" on Main Page:

http://www.asco.org/practice-guidelines/quality-guidelines/guidelines/breast-cancer#/9751