918
Chapter 33
and the new primary tumor that arises in residual breast
tissue (Fig. 33.27).
Surgical treatment for ectopic invasive mammary carci
nomas is wide local excision and regional lymphadenectomy.
Metastases frommammary-type carcinomas that arose in ec
topic breast tissue have been reported in ipsilateral axillary
189
and groin lymph nodes.
192,195
SLN biopsy has been success
fully performed in such situations.
201
The choice of the lymph
node group most likely to be involved by metastases may be
difficult if, for example, the lesion is located over the ster
num or the upper abdomen.
209
Mastectomy is not indicated
if origin in ectopic axillary breast tissue can be documented
and there is no evidence of a separate primary tumor in the
breast. Vulvar lesions are managed by partial vulvectomy
with SLN sampling and/or ipsilateral groin dissection. Many
of these tumors have had an aggressive clinical course, with
systemic metastases reported to have arisen from axillary and
vulvar lesions.
195
Adjuvant treatment with tamoxifen
191,192
or
A
B
FIG. 33.24.
Ectopic breast tissue in axilla with invasive
carcinoma.
A,B:
Invasive carcinoma presenting as a distinct
axillary mass (
Courtesy: Dr. Alexander Swistel
).
B:
Poorly
differentiated ductal carcinoma in ectopic breast tissue in the
axilla.
C–E:
These images are from a single axillary tumor.
C:
A
normal lobule in axillary breast tissue.
D:
ILC in axillary tissue
above a lobule.
E:
Pagetoid LCIS in a duct surrounded by ILC.
