Van Nuys Prognostic index for DCIS, or VNPI
When a patient presents with ductal carcinoma in situ or DCIS (very early stage breast cancer), there might be unclear choices for treatment. Simply put, the attending physicians are faced with a dilemma in terms of balancing aggressive interventions that clearly ‘get all’ of the carcinoma, while at the same time trying not to ‘over-stage’ and over-treat the condition.
Just letting you know, this page is getting old. A new page on DCIS also covers the Van Nuys prognostic index and has up-to-date references there.
No one wants to be put through unnecessary mastectomy or radiation therapy. With experience and with the benefit of ‘team consultations’ and various diagnostic indicators, the most appropriate treatment course will be determined.
The main goal in the treatment of DCIS is to prevent local recurrence. One of the ‘base-line’ diagnostic evaluations for DCIS that has been used for a number of years is the Van Nuys Prognostic Index (VNPI), proposed by doctors at the University of Southern California, Van Nuys.
The VNPI was an attempt to objectively determine the aggressiveness of DCIS in terms of the likelihood of ‘local recurrence’ following ‘breast conserving’ surgeries. The index initially looked at three factors commonly associated with DCIS aggressiveness. These included: overall tumor size, pathologic ‘nuclear grade’ classification ( including presense or absence of necrosis), and the width of clear surgical margins.
Each of these factors were scored from one to three, and the sum-total of values for the three parameters was taken as an indication of probability of local recurrence. The original table is summarized below.
Summary of the scoring system. The table
VNPI scoring system | 1 | 2 | 3 |
Tumor size (diamter in mm) | less or equal to 15 | 16-40 | greater or equal to 41 |
Margin width ( in mm) | less or equal to 10 | 1-9 | < 1 |
Pathologic Classification | non-high grade, (nuclear grades 1 and 2) no necrosis | non-high grade, (nucelar grades 1 and 2)with necrosis | high grade(nuclear grade 3) with or without necrosis |
Overall VNPI score | 3 or 4 | 5-7 | 8 or 9 |
8 year local recurrence-free survival rate.(statistics from the original study, not a prediction) | 97% | 77% | 20% |
8 year breast-cancer specific survival rate.(statistics from the original study, not a prediction) | 100% | 97% | 100% |
At a later time, a fourth factor, “patient age” was added to the index. However, it is generally thought that the ‘age’ factor did not contribute all that much to the overall picture, as it is a well known fact that breast cancer risk increases with age.
Age: | 61 or older | 40-60 | 39 or younger |
---|---|---|---|
add: | 1 point | 2 points | 3 points |
Score | Chance of local recurrence | 5 and 5 years survival rates |
---|---|---|
4-6 points | 1% | 99% / 97% |
7-9 points | 20% | 84% / 73 % |
10-12 points | 50% | 51% / 34% |
Excisional margins tends to be the best indicator for radiation therapy
Treatment strategies will vary from patient to patient and from institution to institution, but VNPI does seem to be useful in determining which patients who have received a surgical excision of DCIS would most benefit from adjuvant radiation therapy. Of the 3 (or 4) predictive factors suggested in the VNPI, the one which is most widely accepted as a useful predictor of local recurrence after breast-conserving surgery is the excisional margin ( the thickness of unaffected tissue removed along with the malignant tumor). It is generally accepted now that women with very small excisional margins are the most at risk and the most likely to benefit from radiation therapy.
Conversely, hospitals might consider using the VNPI to help determine patients for whom the probable risk of local recurrence is so high, even with radiation therapy, that a mastecomy is recommended. It has been demonstrated over time that radiotherapy after breast-conserving surgery can decrease the rate of recurrence, but the debate as to which patients would best be treated by radiation therapy remains open. There is a large percentage of women with DCIS for whom radiation therapy has not demonstrated any clinically significant benefits after excision. However, it must be noted that there is no consensus in the field as to who should or should not receive radiation therapy, and whether or not it is universally beneficial, if not harmful.
Other factors can determine treatment course; mastecomy.
Regardless of the considerations in the VNPI, other factors can determine treatment aggressiveness. There is an informal ‘rule-of-thumb’ that when the tumor is larger than 4 cm, mastectomy is usually undertaken. Sometimes the location of the DCIS tumor within the breast is such that the surgeons cannot leave a negative margin on lumpectomy, so the breast is removed. Multicentric tumors (occuring in more than one breast quadrant) will also most often be treated by mastectomy.
Future directions for early breast cancer/DCIS predictions: Genetics
In terms of predicting the seriousness of DCIS and devising appropriate treatment schemes, researchers are now turning their attention to ‘genotype’ rather than observation of morphological changes. Many breast cancer specialists are now looking for genetic changes that precede morphologic changes (‘after the fact’ changes, diagnostic evidence and description) . If we consider early stage breast cancer/DCIS as a ‘malignant phenotype’ which has not yet ‘learned’ how to become invasive and to metastasize, the best hope for treatment lies in learning about this process and how to prevent it at the genetic level.
References
- Gillear, O., Goodman, A., Cooper, M., Davies, M., Dunn, J., The significance of the Van Nuys prognostic index in the management of ductal carcinoma in situ. World Journal of Surgical Oncology 2008 6:61.
- Boland,G.P., Chan,K.C., Knox,W.F., Roberts, SA, Bundred,N.J., Value of the Van Nuys Prognostic Index in prediction of recurrence of ductal carcinoma in situ after breast-conserving surgery. British Journal of Oncology, (2003) 90:4 p. 426-432
- Silverstein, MJ., Ductal Carcinoma In Situ of the Breast: Controversial Issues . The Oncologist, (april 1998) Vol. 3, No. 2, 94-103
- Douglas-Jones AG, Gupta SK, Attanoos RL et al. A critical appraisal of six modern classifications of ductal carcinoma in situ of the breast (DCIS): correlation with grade of associated invasive disease. Histopathology 1996;29:397-409.
- MacAusland SG; Hepel JT; Chong FK; Galper SL; Gass JS; Ruthazer R; Wazer DE., An attempt to independently verify the utility of the Van Nuys Prognostic Index for ductal carcinoma in situ. Cancer. 2007 Dec 15;110(12):2648-53.
- Schnitt SJ, Harris JR, Smith BL. Developing a prognostic index for ductal carcinoma in situ of the breast. Are we there yet? Cancer. 1996; 77:2189-92.
- Winchester DP, Jeske JM, Goldschmidt RA. The diagnosis and management of ductal carcinoma in-situ of the breast. CA: A Journal for Clinicians. 2000;50:184-200.
- Fisher B, Dignam J, Wolmark N, et al. Lumpectomy and radiation therapy for the treatment of intraductal breast cancer: findings from the National Surgical Adjuvant Breast and Bowel Project B-17. J Clin Oncol 1998;16:441-52.
- Schouten van der Velden AP, Peeters PH, Koot VC, Hennipman A, Local recurrences after conservative treatment of ductal carcinoma-in-situ of the breast without radiotherapy: the effect of age .Ann Surg Oncol. 2006 Jul;13(7):990-8. Epub 2006 May 22.
- Di Saverio S, Catena F, Santini D, Ansaloni L, Fogacci T, Mignani S, Leone A, Gazzotti F, Gagliardi S, De Cataldis A, Taffurelli M., 259 Patients with DCIS of the breast applying USC/Van Nuys prognostic index: a retrospective review with long term follow up. Breast Cancer Res Treat. 2008 Jun;109(3):405-16.
- Silverstein MJ. The University of Southern California/Van Nuys prognostic index for ductal carcinoma in situ of the breast. Am J Surg. 2003; 186: 337-343.
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