Nottingham Prognostic Index Explained

The Nottingham prognostic index (NPI) is used to determine prognosis following surgery for breast cancer.^{[1] [2]} Its value is calculated using three pathological criteria: the size of the tumour; the number of involved lymph nodes; and the grade of the tumour. It is calculated to select patients for adjuvant treatment.

Calculation

The index is calculated using the formula:^[3]

NPI = [0.2 x S] + N + G

Where:

• S is the size of the index lesion in centimetres
• N is the node status: 0 nodes = 1, 1-3 nodes = 2, >3 nodes = 3
• G is the grade of tumour: Grade I =1, Grade II =2, Grade III =3

Interpretation

Score	5-year survival^[4]
>/=2.0 to	93%
>2.4 to	85%
>3.4 to	70%
>5.4	50%

External links

• Online calculator based on Todd et al, 1987 study
• The Nottingham Prognostic Index Biomedical Informatics Research Group
• Nottingham prognostic index Ganfyd

Notes and References

1. Griffiths. K.. Nicholson. R. I.. Campbell. F. C.. P. J. Doyle. Johnson. J.. Elston. C. W.. Blamey. R. W.. Haybittle. J. L.. 1982. A prognostic index in primary breast cancer. British Journal of Cancer. en. 45. 3. 361–366. 10.1038/bjc.1982.62. 1532-1827. 7073932. 2010939.
2. Haybittle. J. L.. Blamey. R. W.. Hinton. C. P.. I. O. Ellis. Elston. C. W.. Williams. M. R.. Dowle. C.. Todd. J. H.. 1987. Confirmation of a prognostic index in primary breast cancer. British Journal of Cancer. en. 56. 4. 489–492. 10.1038/bjc.1987.230. 3689666. 1532-1827. 2001834.
3. Lee. Andrew H. S.. Ellis. Ian O.. 2008-06-01. The Nottingham Prognostic Index for Invasive Carcinoma of the Breast. Pathology & Oncology Research. en. 14. 2. 113–115. 10.1007/s12253-008-9067-3. 18543079. 24513251 . 1532-2807.
4. Book: Garner, Jeff.. Questions for the MRCS vivas. 2004. Arnold. 0340812923. London. 231. In the case of breast cancer, how can these be combined to give prognostic information?. 57193230.