Nottingham Prognostic Index
The Nottingham prognostic index (NPI) is used to determine prognosis following surgery for breast cancer. Its value is calculated using three pathological criteria: the size of the lesion; the number of involved lymph nodes; and the grade of the tumour.
The index is calculated using the formula:
- NPI = [0.2 x S] + N + G
- S is the size of the index lesion in centimetres
- N is the node status: 0 nodes = 1, 1-4 nodes = 2, >4 nodes = 3
- G is the grade of tumour: Grade I =1, Grade II =2, Grade III =3
|>/=2.0 to </=2.4||93%|
|>2.4 to </=3.4||85%|
|>3.4 to </=5.4||70%|
- Haybittle JL, Blamey RW, Elston CW, Johnson J, Doyle PJ, Campbell FC, Nicholson RI, Griffiths K. A prognostic index in primary breast cancer. British journal of cancer. 1982 Mar; 45(3):361-6.
- Todd JH, Dowle C, Williams MR, Elston CW, Ellis IO, Hinton CP, et al. Confirmation of a prognostic index in primary breast cancer. British journal of cancer. 1987;56:489-92
- Galea MH, Blamey RW, Elston CE, Ellis IO. The Nottingham Prognostic Index in primary breast cancer. Breast Cancer Research & Treatment 1992;22(3):207-19
- Garner J, Goodfellow P The Nottingham Prognostic Index Questions for the MRCS vivas 2004 First Edition Page 231