Cancer Genetics and Epigenetics 2017, Vol.5, No.2, 6-10
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3.2 Mirror view
The histology of ACC of the breast is similar to that of their salivary gland counterparts. Tumor tissue arranged in
cribriform type, small tube - trabecular and solid type, the three architectural patterns are often mixed. In each
structure, there was a mixture of glandular epithelium and myoepithelial-basal cells (Lakhani et al., 2012). The
glandular epithelium and myoepithelial-basal cells were respectively composed of the two different structures:
true and false glandular spaces. Luminal cells, characterized by round nuclei and eosinophilic cytoplasm, surround
true gland Lumina containing euphoria neutral mucin. On the other hand, the myoepithelial-basal cells exhibit
central oval nuclei and scant cytoplasm, and form pseudo Lumina, which result from intraluminal invaginations of
the stroma.
3.3 Immunohistochemistry
A variety of markers detected in salivary adenoid cystic carcinoma are also expressed in breast of ACC. The
luminal cells are positive for CK7, CK8/18, epithelial membrane antigen, and CD117(c - kit) (Franzese et al.,
2013). The myoepithelial-basal cells’ marker includs CK5, CK5/6, CK14, CK17, and it also expresses partial
myoepithelial cell markers such as p63, actin, calponin, S-100 protein, vimentin and epidermal growth factor
receptor (EGFR) are often positive (Reyes et al., 2013). The glandular epithelial cells and myoepithelial-basal
cells of Adenoid cystic carcinoma of the breast are most often hormone receptor [estrogen receptor (ER) and
progesterone receptor (PR)] negative, do not express human epidermal growth factor receptor 2 (Her2) (
Kulkarni
et al., 2013
). The immunohistochemical characteristics of breast of ACC are very consistent with the three
negative breast cancer with basal cell-like characteristics.
3.4 Graded
In a way akin to the ACC of the salivary gland, ACCs of the breast are graded according to the proportion of solid
growth: tumors with either cribriform or tubular-trabecular pattern and without solid elements are considered
grade II, tumors with ≤ 30% of solid growth are classified as grade II, and tumors having more than 30% solid
growth are designated grade III, and that tumors with a solid pattern (grade II and III) had a larger tendency
(
Miyai et al., 2014
).
3.5 Precancerous lesions
The incidence of the breast of ACC may be associated with a variety of benign lesions, including micro-gland
adenosis, tubular adenoma, adenomyoblastoma and fibroadenoma (Canyilmaz et al., 2014). The breast of ACC
rarely incorporates other types of breast cancer, but there are also cases of coexistence of breast of ACC and
invasive ductal carcinoma (Righi et al., 2011).
4 Differential Diagnosis
The breast of ACC is the representative breast disease with the sieve structure, often need to be identified with the
disease such as cribriform ductal carcinoma in situ and invasive cribriform carcinoma and breast benign disease
collagenous spherulosis etc (Zhang and Bu, 2014).
5 Treatment
So far, there is still no uniform optimal treatment regimen for breast of ACC, and the choice of specific treatment
regimens varies greatly in clinical practice.
5.1 Surgical treatment
Surgical treatment is one of the main treatment methods of breast of ACC, and there are many kinds of surgical
methods. Radical mastectomy, then modified radical mastectomy was the most reported surgical procedures for
ACC of the breast, simply because it used to be the standard treatment for common breast cancers. Currently
based on its low invasiveness and metastatic potential and good prognosis, breast ACC commonly used
breast-conserving surgery. Local excision alone was performed occasionally in the past with recurrence rates
varying from 6% to 37% (Boujelbene et al., 2012). At present, multiple authors recommend extended resection or
quadrant resection with or without radiation therapy for margin negative tumors (Khanfir et al., 2012). When
