Ductal
carcinoma in-situ: treatment decision breakpoints
reference: Silverstein MJ, Lagios
MD, Craig PH, et al: A prognostic index for ductal carcinoma in situ of the breast. Cancer
77(11): 2267-2274, 1996. There has been an update so that some call the index the USC/VNPI
(Silverstein MJ, "The University of Southern California/Van Nuys prognostic index for ductal
carcinoma in situ of the breast", Am. J. Surg. 186(4): 337-43, 2003.
Update 2016: the biology of the DCIS is considered and CBS is much more aggressively used as promoted by the NAPBC and many other authorities as of 2016.
Update note as of 2010: in our
program, conservative breast surgery for non-invasive breast cancer has become quite complex
as it almost always results in additionally using radiation and medical hormonal blockade
when ER and/or PR positive. Cases are reviewed at a multidisciplinary conference at every
step in surgical treatment decisions until satisfactory surgery is accomplished. Whether to
re-excise and how much depends on patient compliance issues, breast texture & need for
possible MRI based on pathological circumscription or lack there-of, breast texture for
mammographic follow-up and whether the case is suitable for hormonal blockade. So, our
program does not officially use this calculation.
BACKGROUND: There is controversy and confusion regarding therapy
for patients with the non-invasive cancer known as "ductal carcinoma in situ (DCIS) of the breast".
The Van Nuys Prognostic Index (VNPI) was developed to aid in the complex treatment-choice selection
process...with an eye toward statistically characterizing a patient's situation relative to the
issue of conservative breast cancer surgery (CBS): how safe is lumpectomy only vs. lumpectomy PLUS
radiation (XRT) vs. identification of those cases in which mastectomy may be the only advisable
option. It is an index which is not really easy to calculate; therefore, I don't know that treating
doctors actually use the VNPI (ours do not). Rather, they more likely use the general lessons from
the study. Nevertheless, for those who want possibly more precise info., here is how it is done. A
link to a "worksheet" for your use is at the bottom of this page, and it includes the numerical
calculation coefficients for each parameter. Be aware, nevertheless, that mastectomy will be
strongly considered in a "rule-of-thumb" manner for cases in which the:
- DCIS tumor is larger
than 4 cm.
- DCIS tumor location
in breast is such that it is surgically technically difficult to get negative lumpectomy
margins.
- DCIS is multicentric
(tumors in more than one breast quadrant) cancer.
other factors about your breast are not OK for
CBS.
METHODS: The USC/VNPI combines
four significant predictors of local recurrence: overall tumor size
[largest single-direction size measure], closest clear surgical margin width [thinnest
width], pathologic nuclear grade classification, and patient age. Scores of 1 (best) to
3 (worst) are assigned for each of the 4 predictor parameters and then summed/totaled to give
an overall VNPI score ranging from 4 to 12.
Three hundred
thirty-three patients with pure, [non-invasive] DCIS treated with breast preservation/CBS (195 by
excision only [lumpectomy] and 138 by excision plus radiation therapy) were studied with detection
of local recurrence as the end point. The later analysis was of a total of 583 cases.
calculate DCIS tumor
SIZE
calculate DCIS tumor NUCLEAR
GRADE
calculate DCIS tumor CLOSEST SURGICAL
MARGIN
Original CONCLUSIONS: DCIS
patients with VNPI scores of 4-6 can be considered for treatment with excision/lumpectomy
only. Patients with intermediate scores (7-9) show a 17% decrease in their worse (than 3 and
4) local recurrence rates with the addition of radiation therapy (XRT) and are candidates for
surgery PLUS radiation therapy. Patients with VNPI scores of 9-12 exhibit extremely high
local recurrence rates, regardless of lumpectomy only or lumpectomy plus irradiation, and
should be strongly considered for mastectomy.
Calculate the non-beta-weighted VNPI score
AND
chose VNPI Group, below
VNPI
SCORE= tumor-size [_____pts] plus nuclear [_____pts]
plus margin [_____pts] plus age [___pts]=_____total VNPI
points
a study of 333 cases treated by CBS
at the Van Nuys Breast
Center
|
lumpectomy:
Decision Group 1
VNPI points =
4,5,6
|
lumpectomy & XRT:
Decision Group 2
VNPI points =
7,8,9
|
lumpectomy & XRT:
Decision Group 3
VNPI points =
10,11,12
|
data totals
or
averages
|
number of patients
|
196
|
320
|
67
|
583
|
average size
|
8.6 mm.
|
17.3 mm.
|
36 mm.
|
16.5 mm.
|
ave. nuclear grade
|
1.63
|
2.43
|
2.88
|
2.21
|
number of cases
with recurrence
|
4(2%)
|
70(22%)
|
35(52%)
|
109
|
number of cases
with invasive
recurrence
|
0
|
32(46%)
|
15(43%)
|
47 (43%)
|
8 yr. actuarial local recurrence-free survival
rate
|
97%
|
77%
|
20%
|
80%
|
deaths by breast cancer
|
0
|
3
|
0
|
3
|
5&10 yr. breast cancer specific local recurrence-free
survival rate
|
99%/96%
|
83%/73%
|
54%/37%
|
85%/77%
|
breast cancer deaths
|
0
|
4
|
1
|
5
|
5&10 yr. breast cancer specific survival
rate
|
100%/100%
|
100%/97.7%
|
97.6%/97.6%
|
99.7%/98.5%
|
conclusions generalized
from this and other studies
to future DCIS cases
|
POSSIBLE
CBS ONLY
|
CBS plus XRT
|
PROBABLE
mastectomy
|
|
Your VNPI calculation Worksheet
By The Way: how is your spiritual resource?
***give me your comments about this
page***
(posted 17 Dec. 2000; latest update 10 October
2016)
|