402
Chapter 11
The significance of multiple microinvasive foci is yet to be
determined. The finding of microinvasion will lead to ALN
staging, often by SLN mapping, in many patients prior to
consideration of systemic therapy.
430
Advances in the understanding of molecular biology of
breast carcinoma progression and the development of novel
pathway-specific targeted therapy has led to the emergence
of molecular-based individually tailored treatment planning
for invasive breast carcinoma. Increasing understanding of
molecular pathobiology of breast carcinoma progression
underlies the potential of molecular-based “tailored” ther-
apy.
431
Thus far, such advances have not affected the practi-
cal management of DCIS. However, the routine testing of
ER and PR, as well as the emerging adoption of HER2 and
gene signature testing, herald the emergence of such a thera-
peutic approach for DCIS.
432
Novel approaches for the management of DCIS are un-
der investigation. As hypothesized by Espina and Liotta, “the
survival of DCIS cells in the hypoxic, nutrient-dependent in-
traductal niche could promote genetic instability and the de-
repression of the invasive phenotype.” Thus, “understanding
of potential survival mechanisms, such as autophagy, which
might be functioning in DCIS lesions, provides strategies for
arresting invasion at the premalignant stage.”
433
The poten-
tial utility of ductoscopy in detecting occult intraductal le-
sions, and of ductoscopically guided lumpectomy, is under
investigation and could potentially lead to more targeted
lumpectomy procedures.
434
The treatment of DCIS continues to evolve
435
and, in at
least a proportion of cases, remains a “conundrum.”
436
It is
likely that various nomograms
415
andmolecular marker stud-
ies
437
will assume an increasingly significant role in its man-
agement. Advances in various forms of radiologic screening,
and refinements therein, will likely optimize the detection of
DCIS, that is, breast carcinoma in its earliest form.
438,439
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4. Bloodgood JC. The pathology of chronic cystic mastitis of the female
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7. Schultz-Brauns O. Die geschwulste der Brustbrüse. In: Henke F,
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1938;36:225–244.
10. Cheatle GL, Cutler M. Tumors of the breast.
Their pathology, symp-
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Philadelphia: JB Lippincott, 1931.
11. Fechner RE. One century of mammary carcinoma
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. What have
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Am J Clin Pathol
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12. Farante G, Zurrida S, Galimberti V, et al. The management of ductal
intraepithelial neoplasia (DIN): open controversies and guidelines of
residual DCIS was significantly greater if the original mar-
gins were positive, 43% of those with initially negative mar-
gins had carcinoma in the reexcision. There was also a higher
risk (76%) for residual DCIS if the primary focus was 2.5 cm
or larger, but residual carcinoma was present in 57% of re-
excisions for lesions smaller than 2.5 cm. Goldstein et al.
426
analyzed the quantitative relationship between the amount
of DCIS in a lumpectomy and in the subsequent reexcision.
The study was based on 98 patients who had a reexcision
performed after a lumpectomy for DCIS. Residual DCIS was
present in 52 reexcision specimens (53%). Features that were
significantly related to finding DCIS in the reexcision were
multifocal involvement of margins by DCIS or by DCIS ex-
tending into TDLUs and extensive DCIS represented by the
number of slides with the lesion. When DCIS was limited to
one or two slides in the initial excision, no DCIS was detected
in 62% of reexcisions, whereas DCIS was present in 100% of
excisions after initial biopsies with DCIS in more than six
slides.
It must be reemphasized that methods for the quantita-
tion of DCIS are imprecise. No method for measuring the
size of DCIS has gained wide acceptance. Lagios
267
has ob-
served that “quantitation, or better, estimating the extent
of DCIS, should be a collaborative exercise between mam-
mographer and pathologist, but is more a fictional practice
than a reliable fact.” For this and other reasons summarized
by Schnitt et al.,
427
classifications proposed to determine the
treatment of DCIS such as the VNPI, which depend on and
offer precise size categories, may be viewed, at best, as gen-
eral guidelines rather than as strict criteria for making thera-
peutic decisions.
Axillary dissection is not indicated in the majority of pa-
tients with DCIS.
428
Some low ALNs may be taken with the
axillary tail of the breast in the course of a mastectomy. If
the lesion is extensive, DCIS, especially comedo type with
marked duct distortion, it would be prudent to perform SLN
mapping because of concern for undetected invasion. Mi-
crometastases were detected in axillary SLNs from 4 (4.6%)
of 87 patients with DCIS studied by Haigh and Giuliano
429
and in 11 (7.3%) of 150 patients reported by Cox et al.
430
As
noted by Haigh and Giuliano,
429
“if metastases are detected,
microinvasion can be assumed.”
Treatment for the majority of patients with microinvasive
duct carcinoma previously described in the literature has
been mastectomy, as discussed earlier in this chapter. The
outcome overall was relatively favorable after mastectomy,
but the studies were not directly comparable because of dif-
fering criteria for defining microinvasion. Patients treated
by breast conservation therapy were described in several re-
ports with results indicating that this was equally as effective
as mastectomy. These and other published reports indicate
that the presence of microinvasion, as variously defined in
the past or as currently described in the TNM staging sys-
tem (T1
mic
), probably has little independent impact on the
effectiveness of conservation for local control in the breast.
The characteristics of the DCIS that are associated with
microinvasion, such as high grade, the presence of necro-
sis, and lesion size, are crucial determinants for treatment.
