Case #1 Answers:
Answer 1
Ductal carcinoma in situ comprises a group of heterogeneous proliferative
lesions within the ducts of the breast with diverse malignant potential,
with a range of treatment options. It’s a precursor lesion to invasive
ductal cancer. A transition from a benign to a malignant epithelium.
Answer 2
It is estimated that approximately 55,000 new cases will be diagnosed in
2004. Its incidence is increasing and closely parallels the utilization of
screening mammograms, which detects disease in asymptomatic individuals.
DCIS represents 20-40 percent of all mammographically detected breast
cancers.
Answer 3
May present as a palpable mass or more commonly as a mammographic abnormality (stippled micro calcifications) or rarely as bloody nipple discharge. Prior to 1985 DCIS commonly presented as a palpable mass.
Answer 4
By the characteristic mammographic finding sand tissue diagnosis. By
sterotactic biopsy or excisional biopsy.
Answer 5
A variety of histologic types occur in DCIS depending on the architectural
pattern. Solid, Cribriform, papillary and comedo types. The nuclear grading
of these could be low, intermediate or high and again with or without
necrosis in the comedo type. Some classify them as noncomedo and comedo
types.
The comedo variant has been associated with higher proliferative rates, over
expression of Her-2/neu, necrosis and higher incidence of local reoccurrence
after surgical excision.
Answer 6
In the past these patients had modified radical mastectomy and we now
understand this was overkill. Today breast conservation therapy (lumpectomy)
is the treatment of choice with the exception of extensive and diffuse DCIS
or Multifocal DCIS.
Lumpectomy is followed by breast radiation and adjuvant tanoxifen.
Answer 7
Prior to 1985 DCIS was treated by surgery. In 1985, NSABP began a randomized
clinical trial to see if lumpectomy with radiation therapy was more
effective than lumpectomy alone. The results were reported in 1993. Women
with lumpectomy alone developed ipsilateral breast cancer in 16.4 percent
and among those who received lumpectomy plus radiation ipsilateral breast
cancer developed in 7 percent. Radiation not only decreased the incidence of
ipsilateral breast cancer, but also decreased the incidence of invasive
breast cancer by 50 percent.
Answer 8
The presence of moderate/marked comedonecrosis was a significant independent
factor for predicting local recurrence. Uncertain or involved margins was
another predictive factor for recurrence.
Answer 9
No. DCIS by definition is intraductal carcinoma and hence metastasis does
not occur, unless there is microinvasion.
Answer 10
NSABP – B-24 study that followed B-17 study compared the effects of
Tamoxifen vs. Placebo following lumpectomy and radiation therapy with
tamoxifen. The incidence of ipsilateral invasive breast cancer was reduced
from 3.4 percent to 2.1percent contralateral breast cancer was reduced from
13 percent to 8.8 percent.
Currently adjuvant tamoxifen is prescribed for all patients with DCIS
following lumpectomy and radiation unless specific contraindication exists.
The best treatment for DCIS is in the process of evolution.
Answer 11
Answer 12
Answer 13
Answer 14
Answer 15
Answer 16
Answer 17
Answer 18
Answer 19
Answer 20
Answer 21
Answer 22
Answer 23