ULTRASOUND OF THE BREAST - Pathology

For normal anatomy and scanning protocol

Normal Breast

Normal breast tissue showing: The premammary zone (skin and overlying breast fat) The mammary zone (fibroglandular tissue) The retro-mammary zone (predominantly fat and the muscles of the chest wall)	Normal lactating breast tissue. The prominent fluid filled ducts and their echogenic epithelial lining is readily visible.

BREAST CYSTS

• Simple V's Complex or complicated cysts
• To be simple it must be:
  
  1. Anechoic
  2. Well cicumbscribed
  3. Have posterior enhancement
  4. It's height should NOT exceed it's width.

A simple breast cyst	A complex breast cyst: Sedimentary movement may be visible by scanning the patient erect. Fine needle aspiration and cytological assessment can confirm the diagnosis. At the least, a follow-up ultrasound should be performed.

A simple cyst adjacent to a complex cyst, (confirmed by FNA to be a haemorrhagic cyst)	The material in this breast lesion is not in the dependent portion, therefore excluding mobile debris or fluid. Whilst it may represent a mural nodule, the neat linear edge suggests likely adherent haemorrhage. A fine needle aspiration may still be warranted. Or at least a 2 month follow-up scan.

FIBROADENOMA

• Benign.
• Well circumscribed solid ovoid mass with subtle posterior enhancement.

Histological confirmation via a biopsy is still recommended. A core biopsy is preferrable.

Well cicumscribed solid ovoid mass with subtle posterior enhancement. Histological confirmation via a biopsy is still necessary. A core biopsy is preferrable.	Fibroadenoma: A Phylloides tumour can have similar appearances and be indistinguishable from a fibroadenoma. If the mass is greater than 5cm or rapidly increasing in size a Phylloides should be considered even if a fine needle biopsy has suggested a diagnosis of Fibroadenoma.

PHYLLOIDES TUMOURS (also called Phyllodes)

• Very similar to fibroadenomas in appearance.
• Generally more rapidly growing.
• Poorly diffentiated by fine needle biopsy, so core biopsy is recommended.

PAPILLOMA

Whist often benign, their malignant tendancy generally leads to removal. Multipe papillomas have been shon to carry a far greater risk than solitary. (REF: Ohuchi N, Abe R, Kasai M. Possible cancerous change of intraductal papillomas of the breast. A 3-D reconstruction study of 25 cases. Cancer. 1984;54:605.)

• They are fibrovascular growths within milk ducts behind the nipple.
• Radiographic ductography has often been employed to confirm the diagnosis, however advancements in Ductoscopy are proving to be of great benefit.

For further information on Papillomas

For a document giving a proposed algorithm for management of suspected papilloma From: Int Semin Surg Oncol. 2006; 3: 1. Published online 2006 January 17. doi: 10.1186/1477-7800-3-1

A papilloma in a markedly dilated duct.	The same papilloma imaged in two planes

The nipple generally casts an acoustic shadow. To overcome this use either a stand-off pad or thick gel.	Accessory nipple at the lateral areola.

BREAST CARCINOMA

 Common ultrasound appearance:

• Poorly circumbscribed, hypoechoic mass.
• Height greater than width.
• Posterior shadowing

You may also see: punctate, micro-calcifications, tethering of adjacent tissues or the mass crossing tissure boundaries.

Elastography is also an emerging technique in assisting suspicion levels.

Types of Breast Cancer

****  Breast cancer grading and specific differentiation must involve a series of investigations and not be based on ultrasound alone. 

Carcinoma in-situ

 Indicates that the cancer is still contained entirely with the tissue of origin and not penetrated tissue boundaries (a histological diagnosis)

• Ductal Carcinoma In-Situ (DCIS) - The Cancer originated within breast milk ductal epithelium and is still contained by the ductal walls.
  
• Lobular Carcinoma In-Situ (LCIS)-
  

As the name suggests, the cancer has crossed multiple tussue boundaries, and is no longer contained in the tissue of origin.

• Infiltrating Ductal Carcinoma (IDC)
  
• Infiltrating Lobular Carcinoma (ILC)

There are several grades using the TNM grading

Medullary Carcinoma

•  Has better defined margins so has a better prognosis than ductal or lobular. Only accounts for approximately 5% of breast cancers.

Colloid (or Mucinous) Carcinoma

•  Rarer again. Arises from mucous secreting cells. Also a better prognosis.

Tubular Carcinoma

•  Is a form of Ductal carcinoma with tubular cells visible on histo-cytology. With increasing early (sub-clinical) screening, tubular carcinomas are being detected with increased frequency.

Paget's Disease of the breast

•  Greater than 97% of patients with Pagets diseaes of the nipple have an underlying breast cancer (REF breastcancer.org)
• Accordingly, accurate diagnosis is important.
• Clinically, the patient may have an eczema-like rash around the nipple/areola and nipple discharge. There may be itching/tingling or hypersensitivity of the nipple.
• As many Pagets related breast cancers begin in the ducts behind the nipple, ensure this area is scanned thoroughly with high resolution equipment.
• Mammography and Breast MRI are appropriate investigations in these patients

For detailed information on Paget's Disease of the breast

Inflammatory Breast Cancer

•  Rare but aggressive
• The cancer blocks the lymphatic drainage of the cutaneous tissues.
• Unexplained onset of reddened, swollen, firm breast in the abscence of  infection.

For detailed information in inflammatory Breast Cancer

The posterior shadowing and irregular outilne raises the suspicion from fibroadenoma to possible carcinoma.	The core biopsy needle is seen to transverse this complex lesion.

Ductal Carcinoma

This focal Ductal Carcinoma is easily seen. The red arrows indicate the microcalcifications. Note how readily visible these are on the adjacent mammogram confirming the importance of the complimentary modalities. DCIS is by far more common than LCIS, and more importantly, it should be distinguished as a clearly malignant lesion. Ductal epithelial cells undergo malignant transformation and proliferate intraluminally. Eventually, the cells outstrip their blood supply and become necrotic centrally. This debris can calcify and be detected mammographically. Moreover, the lesions also may be palpable clinically. Five pathologic subtypes have been identified: comedo, papillary, micropapillary, solid, and cribriform. Most lesions represent a combination of at least two of these subtypes. The presence of comedo necrosis is an independent risk factor for subsequent ipsilateral breast cancer (NSABP-B17). REF: http://emedicine.medscape.com

DC (Ductal Carcinoma) The extent of this carcinoma is far more evident on the mammogram. The peripheral mass and extensive micro-calcification extending towards the nipple is readily apparant.

Infiltrating Lobular Carcinoma: Infiltrating lobular carcinoma has a much lower incidence and comprises less than 15% of invasive breast cancer. It is characterized histologically by the Indian file arrangement of small tumor cells. Like ductal carcinoma, these typically metastasize to axillary lymph nodes first. However, it also has a tendency to be more multifocal. Despite this, the prognosis is comparable to that of ductal carcinoma. Ref: http://emedicine.medscape.com

Lobular breast carcinoma. Transverse.

GYNAECOMASTIA

• Is the abnormal enlargement of rudimentary male breast tissue.
• Can be idiopathic, related to steroid abuse or associated with hormonal treatments such as prostate cancer therapies.
• May present as a retroareolar lump with or without pain.
• On ultrasound it will be hypoechoic with spiculations radiating away from the nipple.

Male breast gynaecomastia - mild. A tender (often) lump deep to the nipple with spiculations radiating away from the nipple. Can be unilateral or bilateral.	Male breast gynaecomastia-acute. Mildy increased vascularity can be seen. Can be idiopathic, related to steroid abuse or associated with hormonal treatments such as prostate cancer therapies.

BREAST IMPLANTS

• Should be scanned with the patient positioned as normal.
• Treat the scan as a 2-fold examination:

1. The breast tissue.
2. The deeper implant. This may require lower frequency or a curved probe to investigate.

The implant should be anechoic with well defined margins. Folds are commonly seen in the implant surface.

Also, small traces of simple fluid will be seen overlying the implant but is contained by the overlying fibrous capsule that contains the implant. This fluid is routinely seen within the implant folds (see image below).

Most saline implants will have a small valve visible (see image below)

For a link to breast implant types, valves and history.

The normal appearance of a fold in an implant with normal physiological amount of capsular free fluid. The mammogram below shows the typical appearance of folds.	A normal finding of an implant 'valve'. Also visible in the mammogram below.

The typical appearance of folds in a breast implant.

Most often there is a rupture only of the elastomer biluminal shell of the implant. The ruptured material is then contained by the fibrous capsule generated by the body.	Silicone extruded outside the fibrous capsule. This can be seen as an island of poorly defined echogenic material ,distant to the implant, casting a 'dirty' shadow .

A large siliconoma. This is a palpable lump of silcone. The cystic space within the silicon is a commonly seen variant.	Silicon has made its way into the intercostal space.

COLLECTIONS AND INFECTIONS

SEROMA

• A post-operative seroma is not an uncommon finding in the post mastectomy patient.
• They can be very painful and rapidly increase in size.
• Therapeutic ultrasound guided fine-needle aspiration can be performed as required to relieve symptoms.

	Click to enlarge
A post-operative seroma is not an uncommon complication post mastectomy.	Panoramic view of a breast seroma.

HAEMATOMA

• May occur following trauma, biopsy or surgery.
• Seatbelt injuries cause substantial cutaneous bruising. This usually appears on ultrasound as diffusely increased echogenicity of the underlying breast tissue, perhaps with some small hypoechoic collections.

	Click to enlarge
A large, expansive breast haematoma adjacent to a breast implant.	Panoramic ultrasound of an extensive breast haematoma

ABSCESS

• Acutely tender lump or swelling with erythema.
• May be secondary to lactating mastitis