The triple assessment is the gold standard when it comes to diagnosing breast cancer but, whilst not new, it is still not being used by all clinicians. Every patient should have an ultrasound and mammogram (depending on their age) and, wherever possible, a needle biopsy – preferably a core needle biopsy. This allows the surgeon to understand the nature of the breast cancer and to discuss treatment options with the patient, prior to them undergoing surgery.
ASSESSING THE BREAST
Doctors use three modalities to assess the breast as it reduces the chances of missing a cancer. This is called the triple assessment:
- Clinical examination
- Mammography and ultrasound
- Core needle biopsy.
Once a cancer has been diagnosed there is no harm in taking a few days to discuss the different treatment options. Waiting a day or two, participating in the treatment discussions and getting to understand the different treatment options will help to ensure the best psychological, cosmetic and cancer outcomes.
It is important to realise that in most cases it is not necessary for a women to undergo a general anaesthetic to determine whether the lump in her breast is a cancer or not, this is the important concept behind the triple assessment. Incision and excision biopsies of breast masses for diagnostic purposes should not be done unless a needle biopsy has failed to provide adequate pathological information. BUT, no cancer should be treated without a core needle biopsy result.
A specialist radiologist, using ultrasound to guide the process, is the only person who should carry out needle biopsies. Doctors do not have eyes on their fingers! No matter how good a doctor thinks they are at locating a mass for biopsy, using an ultrasound probe is far more accurate. Any doctor who wants to do “blind” needle biopsies in their consulting rooms should be discouraged!
FINE NEEDLE ASPIRATION (FNA)
With this form of biopsy the pathologist examines the cytology – the cell morphology (cell form and structure). FNA can tell if the lump (tumour) is a cancer or not. Because the pathologist is just viewing cells down a microscope, they can’t tell if the cancer is invading (awake) or non-invading (sleeping).
Method: A needle is attached to a syringe, inserted directly into the breast mass and suction maintained on the plunger. For solid lesions, or lumps, several passes of the lump are made so that samples from various areas can be obtained for analysis of the cells.
The sample material is placed on a microscope slide where it is chemically stained. The staining is for cytology and receptor analysis. Receptor analysis indicates a patient’s likely hormonal response to endocrine manipulation of their tumour.
Significance: Cytology tells us whether a lump is benign or malignant. FNA is most commonly done on lymph nodes and not on the actual cancer in the breast, as it does not inform on the detailed personality of the cancer.
Histopathology examines tissues and is necessary when deciding whether a cancer is invasive (infiltrating) or in situ (has not spread beyond the basement membrane of the lining cells). Breast lumps can be biopsied for histology by taking a core of tissue, using local anaesthetic.
Recent international reviews declare core biopsies superior to FNA in terms of diagnosis.
Method: A core biopsy is usually obtained using a hand driven device (Tru-Cut) or a pneumatic gun (Biopti-Gun). The extra tissue obtained allows the pathologist to type, stage (invading) and grade the cancer as well as test for certain receptors such as HER 2, oestrogen and progesterone receptors.
Significance: If the breast lesion is found during screening mammography, a mammogram guided core biopsy will be done, as the lump is not yet palpable (cannot be felt). These “silent breast masses” can be accurately located using technology built into the mammogram apparatus. The radiologist can take a core of the suspicious area. If the pathologist says the cells are benign, this avoids an unnecessary operation
to excise (surgically remove) the suspicious area.
A special type of core biopsy called a Mammotome, or Vacuum Assisted Biopsy, is also available. Vacuum Assisted Biopsy is an automated, image guided, biopsy tool capable of obtaining a number of adjacent core samples. The vacuum pulls tissue into the probe and sucks the tissue into the collection chamber. Vac-assist can be used with x-ray or sonar guidance and is highly reliable in confirming a lack of malignant change in radial scars and atypical ductal hyperplasia.
Both FNAs and core biopsies are accurate and do not spread cancer cells. They allow the doctor to plan a definitive treatment, and the patient to understand the options and diagnosis prior to surgery. A core biopsy is preferable for diagnosis, as the information gained allows an oncologist or cancer specialist to direct treatment, due to the specific markers that can be studied in the bigger core biopsy specimen.
HOOKWIRE NEEDLE BIOPSY
This procedure can be used as a diagnostic tool or to define an area for surgical removal.
A diagnostic hookwire biopsy is done when an area on a mammogram is suspicious and a needle biopsy result is inconclusive, unsuccessful or equivocal. The area of the breast is marked on a mammogram and the wire is inserted, under local anaesthetic, into the area that is suspicious. This will later guide the surgeon on the area
to be removed.
A therapeutic hookwire is done when an impalpable (cannot be felt) breast cancer is detected on mammography and a core biopsy has confirmed breast cancer. A hook wire is inserted into the cancer under mammography control. Now the surgeon can readily excise the cancer including the hooked needle. This avoids removing the entire breast (to be avoided at all costs) in an attempt to find the lesion.
A variation on the hookwire is the ROLL (radio-isotope localisation) technique where an isotope is injected into the suspicious area and a hand-held probe, (a gamma probe) is used to locate the area.