Calculating H-Score

Get Permission

Immunohistochemistry results can be further evaluated by a semiquantitative approach used to assign an H-score (or “histo” score) to tumor samples.1,2 First, membrane staining intensity (0, 1+, 2+, or 3+) is determined for each cell in a fixed field. The H-score may simply be based on a predominant staining intensity, or more complexly, can include the sum of individual H-scores for each intensity level seen. By one method, the percentage of cells at each staining intensity level is calculated, and finally, an H-score is assigned using the following formula:

[1 × (% cells 1+) + 2 × (% cells 2+) + 3 × (% cells 3+)]

The final score, ranging from 0 to 300, gives more relative weight to higher-intensity membrane staining in a given tumor sample. The sample can then be considered positive or negative on the basis of a specific discriminatory threshold. ■


1. Hirsch FR, Varella-Garcia M, Bunn PA Jr, et al: Epidermal growth factor receptor in non-small-cell lung carcinomas: Correlation between gene copy number and protein expression and impact on prognosis. J Clin Oncol 21:3798-3807, 2003.

2. John T, Liu G, Tsao M-S: Overview of molecular testing in non-small-cell lung cancer: Mutational analysis, gene copy number, protein expression and other biomarkers of EGFR for the prediction of response to tyrosine kinase inhibitors. Oncogene 28:S14-S23, 2009.

Related Articles

No Benefit of High- vs Standard-Dose Radiotherapy or Addition of Cetuximab to Chemoradiation in Stage IIIA/IIIB NSCLC

As reported in The Lancet Oncology by Jeffrey D. Bradley, MD, of Washington University, and colleagues, the phase III Radiation Therapy Oncology Group 0617 trial showed no survival benefit of high- vs standard-dose radiotherapy or addition of cetuximab (Erbitux) to concurrent...




By continuing to browse this site you permit us and our partners to place identification cookies on your browser and agree to our use of cookies to identify you for marketing. Read our Privacy Policy to learn more.