BENIGN MALE BREAST DISEASE
1.GYNAECOMASTIA (See figures 1-3)
The most common abnormality within the male breast is gynaecomastia(3).
Affects up to 40-60% of the male population (5).
It is caused by benign ductal and stromal proliferation (4).
There are various etiologies of gynaecomastia some of which are:
- Physiological - during infancy,
adolescence or senescence.
- Drugs – marijuana,
cimetidine,
spironolactone etc.
- Hormonal – Klinefelter syndrome (XXY)
- Cirrhosis and chronic renal disease
- Neoplasms e.g.
germ cell tumours
- Idiopathic
Clinical Presentation:
Usually presents as a soft,
tender,
concentric,
mobile subareolar mass.
Unilateral or bilateral.
There are three main imaging patterns of gynaecomastia,
which include
- nodular
- dendritic
- diffuse
Nodular Gynaecomastia
Represents the early florid phase of ductal and stromal proliferation.
Usually seen in patients with gynaecomastia for less than 1 year ( 3).
Can be reversible if stimulus eliminated.
Mammography:
fan shaped density radiating from the nipple
irregular borders as it usually blends into the surrounding fat tissue
Ultrasound:
hypoechoic subareolar fan shaped density
can be hypervascular due to proliferation of stroma
Histology:
proliferation of the intraductal epithelium
periductal inflammation and oedema
Dendritic Gynaecomastia
Represents the quiescent,
fibrotic phase
Usually seen in patients with gynaecomastia for more than 1 year (3).
Usually irreversible due to the fibrotic process
Mammography:
fingerlike projections extending into the retroareolar tissue
may extend into the upper outer quadrants
Ultrasound:
flame-shaped subareolar density radiating from the nipple into deeper adipose tissue
Histology:
stromal fibrosis
dilated ducts
Diffuse Gynaecomastia
Mammography:
heterogeneously dense nodular breasts which may appear similar to a heterogeneously dense female breast
Ultrasound:
diffuse glandular gynaecomastia
may mimic malignancy (however there is usually no mass on clinical examination and no secondary features suggestive of malignancy in gynaecomastia).
2.
PSUEDOGYNAECOMASTIA
True gynaecomastia must be distinguished from pseudogynaecomastia,
which is fat deposition within the breasts typically seen in obese patients.
Manifests as unilateral or bilateral breast enlargement rather than a discrete mass.
Caused by benign diffuse proliferation of normal fatty tissue rather than stimulation of ductal and stromal elements.
3.
FIBROADENOMA (See figure 4)
Extremely rare in men due to the lack of lobules in the male breast
Men on oestrogen therapy have increased risk of developing fibroadenomas.
Mammography:
well-circumscribed,
oval or round mass
occasional coarse calcification
Ultrasound:
well-circumscribed,
homogenous
oval hypoehoic mass
gentle lobulations
smooth thin echogenic capsule
variable acoustic enhancement
homogenity
4.
GRANULAR CELL TUMOUR
Uncommon,
typically benign breast tumour
Male to female ratio 1:9
Clinical presentation – unilateral (bil.
rare finding in men),
solitary,
firm,
hard,
painless mass
Mimics malignancy with occasional features of skin retraction and nipple inversion
Mammogram :
round,
well circumscribed mass/spiculate mass/indistinct mass
occasionally calcification
Ultrasound :
variable architecture
circumscribed/angular/spiculate margins
variable acoustic
5. HAEMANGIOMA (See figures 5 & 6)
Uncommon benign stromal tumour predominantly seen in elderly men
Even after excision which is the treatment of choice,
these lesions can recur.
Typically do not under malignant transformation (1).
6.
MYOFIBROBLASTOMA (See figure 7)
Uncommon benign stromal tumour predominantly seen in elderly men
Even after excision which is the treatment of choice,
these lesions can recur.
Typically do not under malignant transformation (1).
7. PSEUDOANGIOMATOUS STROMAL HYPERPLASIA (PASH)
Benign proliferative condition that is thought to represent a hormonally driven process involving stromal myofibroblasts in the breast (1)
In men PASH is associated with gynaecomastia.
Clinical presentation: commonly manifests as incidental microscopic foci on biopsy of other lesions. Rarely presents as a palpable mass.
Mammogram:
noncalficied,
circumscribed or partially circumscribed masses
rarely with indistinct or spiculated borders
Ultrasound:
circumscribed,
ovid,
homogenous,
hypoechoic mass.
hetergenous tissue or increased echotexture (less common presentation).
7. SCHWANNOMA (See figure 8)
A rare male breast neoplasm arising from Schwann cells of peripheral nerve sheaths.
Schwannomas associated with Neurofibromatosis type 2 are more cellular than the sporadic type and have a higher chance of malignant transformation.
Clinical presentation in men: smooth,
soft,
painless mass.
Mammogram:
nonspecific,
well-defined,
round/oval mass
Ultrasound:
well-defined,
hypoechoic,
solid mass with variable acoustic enhancement.
rarely a central cystic component
8.
NODULAR HIDRADENOMA (See figure 9)
Nodular hidradenoma is a rare benign skin adenexal tumour which arises from the eccrine sweat glands.
These tumours are extremely rare.
MALIGNANT MALE BREAST DISEASE
Most common histological subtype of male breast cancer is invasive ductal carcinoma which makes up approximately 80% of breast cancer cases in men (4).
Ductal carcinoma in situ (DCIS) is the second most common subtype (approximately 5%).
Less common subtypes
- infiltrating mammary carcinoma
- invasive papillary carcinoma
- metastasis to the breast from extramammary primary malignancy is extremely rare (See figures 10-12)
Male breast cancers account for up to 1% of all breast cancers.
Mean age = 59 years (between 6 and 1 years higher than women)
Worse prognosis due to the later presentation in men compared to women (8).
1.
Invasive Ductal Carcinoma (See figures 12-20)
Clinical Presentation:
irregular,
subareolar mass - eccentric to the nipple
nipple retraction and skin ulceration.
25% of cases – bloody nipple discharge(4)
50% of cases axillary nodal metastasis at presentation (9)
Mammography:
high density,
usually ill-defined or spiculated.
15% are well-circumscribed – rounded,
oval +/- (micro)lobulations
Skin thickening, ulceration,
nipple retraction,
axillary lymphadenopathy
MCC in 13-30% - coarse and less linear than in female breast cancer (8)
Ultrasound:
solid,
hypoechoic subareolar mass that is eccentric to the nipple
Ill-defined borders however can also have well-defined margins with evidence of lobulations.
variable degree of acoustic transmission.
2. Papillary Carcinoma
Occurs twice as common in men than women (4)
Important Note: benign cystic disease does not occur within the male breast so cystic lesions found in the male breast should generally be biopsied
Clinical presentation: subareolar mass
Mammogram:
subareolar,
irregular/well-circumscribed/ spiculated mass
occasional calcifications
Ultrasound:
complex cysts + mixed solid and cystic features
solid nodules or papillary projections arising along a cyst wall are chacteristic of papillary carcinoma
3. Invasive Lobular Carcinoma
Clinical presentation: painless mass in the older male patient
Mammogram:
spiculated mass /architectural distortion/asymmetrical density or normal mammographic features.
Ultrasound:
irregular mass,
hypoechoic,
heterogenous occasionally - well-circumscribed mass/shadowing/occult
Less than 4% of all cases of breast cancer
Association with oestrogen therapy and Klinefelter syndrome
4. Adenoid Cystic Carcinoma
Rare tumour
Mammogram:
well-defined or irregular mass
parallel growth pattern
smooth,
macrolobulated or indistinct margins
occasionally architectural distortion/aymmetrical density
Ultrasound:
hetergenous or hypoechoic irregular mass.
5. Basal Cell Carcinoma of the Nipple
Basal cell carcinoma is a common skin malignancy but a rare,
aggressive tumour of the nipple areolar complex (NAC)
Clinical presentation: nipple mass +/- ulceration/bleeding
occasionally BCC of NAC is pigmented which can therefore mimic melanoma
Mammogram:
nipple mass +/- MCC
Ultrasound:
well-defined nodular mass
very rarely axillary lymph node metastases
6. Dermatofibrosarcoma
Rare tumor of the male breast
Arises from the dermis and invades the subcutaneous soft tissues
Clinical presentation: middle aged men
Erythematous,
indurated,
subcutaneous,
firm nodule
slow growing
Mammogram:
dense mass with no calcification
Ultrasound:
ovid lesion with a well-defined or microlobulated margin
hetero/homogenous,
hypoechoic mass +vascularity
7. Liposarcoma
Rare tumour of the breast.
Clinical presentation : painful,
unilateral mass
slow growth
no axillary lymphadenopathy or skin changes
Mammogram:
large encapsulated/circumscribed,
dense mass.
Ultrasound:
heterogeneous,
hyperechoic mass
8. Haematopoietic Malignancies (See figures 22 & 23)
Lymphoma is the commonest haematopoeitic malignancy of the breast.
Non-Hodgkin B-cell lymphomas is the commonest subtype.
(See figures 11 & 12)
Mammogram:
LYMPHADENOPATHY – bilateral multiple enlarged dense axillary lymph nodes with irregular cortex and loss of fatty hilum.
circumscribed or indistinctly marginated intramammary masses
occ.
solitary mass/architectural distortion/mammographically occult
no calcification
Ultrasound:
hypo/hyperechoic heterogeneous mass
posterior acoustic enhancement
Leukemia
A disease of children and young adult
Spreads haematogenously
Rare in the breast
Mammogram:
unilateral/bilateral masses
breast enlargement +/- axillary lymph node enlargement.
Ultrasound:
mixed echotexture in masses
peripherally increased architecture with anechoic centers
margins lobulated or irregular
possible increased vascularity
CUTANEOUS LESIONS
1.
LIPOMA
2nd commonest benign lesion in the male breast
Clinical presentation: soft,
palpable,
mobile,
well-circumscribed subcutaneous mass
Differential diagnosis: fat necrosis however a history of trauma and coarse/dystrophic calcification may be present.
Mammography:
difficult to detect as a separate entity from the surrounding fat occasionally a thin radiopaque capsule can be seen
Ultrasound:
solid,
well-defined,
hyperechoic,
homogenous subcutaneous mass
occasionally posterior acoustic enhancement or an encapsulated margin
2. EPIDERAMAL INCLUSION CYST (See figure 24)
3rd commonest benign lesion in the male breast
Caused by proliferation and implantation of epidermal elements within a circumscribed
space in the dermis.
Clinical presentation: soft,
fixed to the skin,
well-defined,
cutaneous/subcutaneous mass
Mammography:
well-defined,
dense,
peripheral mass
Ultrasound:
well-defined,
hypoechoic mass
variations : solid,
complex heterogenous mass.
the majority extend into the dermis thereby suggesting a cutaneous origin
3. HAEMATOMA
Can result from preceding trauma,
surgery,
biopsy (rare).
Occasionally can be spontaneous in patients on anticoagulation
Mammography:
variable findings – single nodule/diffusely increased glandular tissue
density/radiolucent nodule(s) with calcification
eventually fat necrosis may occur
Ultrasound:
variable findings – fluid collections/solid nodule(s)/cystic nodule(s)/
diffuse parenchymal abnormalities/calcified nodule(s)
AUGMENTED MALE BREASTS (See figure 25)
A common practice in countries such as South America is injection into the male breast of highly viscous fluids e.g paraffing,
silicon,
automobile transmission fluid).
Mammogram:
injected fluids may appear as extensive MCC and coarse calcification.
Long term complications:
scelorosing lipogranulomatosis (inflammation and necrosis).