Thermal Ablation for Breast Cancer

Microwave breast tumor ablation.

NO SURGERY

Breast Tumor Ablation

Breast cancer surgery has evolved considerably since the days of those draconian radical mastectomies and disfigurement, to a far more conservative surgical approach today!

Yet, many requisite breast tumor resections – particularly within the EU -- have now been replaced with safe and effective thermal ablations (either cryoablation or microwave ablation) with considerable rarity in the U.S. because of the lack of FDA approval, and no health insurance reimbursement.

Microwave breast tumor ablation (MWA) is one of the newer modalities of thermal ablation which has been proven to be safe and effective in the destruction of many primary and metastatic breast tumors. MWA uses electromagnetic waves to produce a “directed” heat that destroys the cancerous tumor cells without requiring surgery or causing body disfigurement.

Breat Tumor Ablation

MWA is a minimally invasive technique widely used in the treatment of tumors of various organs. A microwave breast tumor ablation is similar to an ultrasound-guided needle biopsy performed by an interventional radiologist with the patient awake and comfortable.

Once the probe has entered the tumor cells, extreme heat is transmitted directly into the cancerous tumor cells, causing instantaneous cell death/destruction (well within preset margins) without causing harm to healthy tissue.

Pts can undergo MWA multiple times, either singularly or with other treatments if indicated.

The advantages of MWA as compared to conventional surgery, are faster recovery, reduced morbidity and mortality, minimal, if any, body disfigurement, accurate targeting under ultrasound or CT guidance, short outpatient treatment, and easily repeatable if residual lesions reappear.

MWA Preparation

  • Physical exam, complete analysis (CBC, Blood Chemistry, Urinalysis).
  • Imaging Studies: X-Rays, CT, or MRI when indicated.
  • Ascertain if the patient has taken any of the following:
    • aspirin
    • clopidogrel
    • arthritis medicines
    • blood thinning medicines such as warfarin, rivaroxaban, and dabigatran

The procedure begins with an ultrasound detecting the exact location of the cancer breast tumor, followed by a local anesthetic injected into the skin above the targeted area. A small (3mm) skin incision is made. Followed by a needle-like instrument called a probe inserted through the incision and placed into the center of the tumor. The procedure takes approximately 30 minutes, with the entire process taking about 1 hour from start to finish.

Post MWA Expectations

  • Breast Bruising: Bruising of the breast is normal and usually develops in the first couple of days after the procedure, gradually disappearing within several days. Bruising may extend to the flank below the breast.
  • Fluid Drainage from Skin Puncture Wound. The small puncture wound will typically drain watery and bloody fluid for the first few hours after the procedure. The drainage should stop within 24-48 hours after the puncture wound sealing. Extra gauze pads to place inside your bra to absorb the drainage. Change the gauze as often as needed to keep your clothes dry.
  • Some Persistent Swelling: MWA usually causes swelling at the insertion site. This will make the tumor feel much larger than it did before the procedure. For example, the MWA of a 2 cm tumor will produce a lump about the size of a large egg or small lemon which will gradually disappear over the next year or so as your body absorbs the ablated tissue.
  • Skin Redness: Redness of the skin is normal. It’s similar to a mild sunburn that will heal after a few days.

Notify ICCA if

  • Shortness of breath
  • Increasing pain that is not relieved by Tylenol
  • Fever (Temperature ≧ 38.5C or 101F) or chills that develop after the procedure
  • Wound bleeding that persists for more than two hours and does not diminish gradually
  • An open sore appears on the breast after the procedure

Potential Imaging Deficiencies

There is a large body of evidence that MWA effectively destroys multiple cancer types. However, the key requirement for successful MWA is a well-defined tumor that can be accurately targeted.

Unfortunately, the complete extent of breast cancer might not be detectable on mammography, ultrasound, MRI, or thermography – which is why a PET/CT is often the preferred imaging of choice.

This is especially true for non-invasive breast cancer or ductal carcinoma in situ (DCIS), which is typically invisible unless it is associated with microcalcifications. DCIS co-exists with most invasive breast cancer, and may also extend a few millimeters or more beyond the main cancer mass.

There may also be small, undetectable areas of invasive cancer outside the main tumor. Unlike surgery, which permits microscopic examination of the surgical margins to determine if cancer extends beyond the visible tumor, MWA does not facilitate microscopic examination of the tissue surrounding the visible tumor. Consequently, when MWA is performed for breast cancer, our physicians intentionally ablate an area 1-2 cm beyond the visible tumor to treat undetectable DCIS and/or invasive cancer in the immediate perimeter of the visible tumor.

MWA and DCIS

Many patients with DCIS (ductal carcinoma in situ, non-invasive breast cancer, or stage 0 breast cancer) can undergo MWA. Requirements include a small area of involvement (typically 4.5 cm or less) and DCIS that is visible by ultrasound since MWA is usually performed under ultrasound guidance.

When DCIS is not visible by ultrasound, the treating physician can arrange for the insertion of an ultrasound-visible marker in the center of the area of DCIS (or next to your existing biopsy site marker), which is used as a target for the MWA procedure.

Placement of the ultrasound-visible marker is usually performed under stereotactic or mammographic guidance using a procedure similar to your original stereotactic needle biopsy. In some cases, the marker placed at the time of the original needle biopsy is already ultrasound visible. When this is the case, the placement of another ultrasound-visible marker is unnecessary. Our treating physicians will review your mammogram, ultrasound, and MRIs to assess your eligibility for MWA, and to determine if placement of an ultrasound-visible marker is needed.

MWA followed by Short-course Radiation and/or Chemotherapy

One of the major misconceptions about MWA is that it completely replaces the need for radiation or systemic medicines. Radiation is usually recommended with surgery to treat undetected residual disease in the surrounding breast, skin, or lymph nodes. The addition of radiation to surgery is generally associated with a 60% reduction in the risk of recurrence in the breast and lymph node area. Moreover, nearly all breast cancer patients with metastatic nodes should consider undergoing radiation pre- or post-micro ablation!

Drug therapies like anti-estrogen therapy and chemotherapy have a role after surgery to treat cancer cells that had already escaped the breast. The same principle applies to MWA. Most patients treated with MWA would benefit from some form of anti-cancer therapy. Women certainly have the right to refuse radiation and medication therapy. However, the primary intent of MWA is to replace surgery, and other measures may be needed to minimize the risk of potential recurrence, especially for larger or more aggressive tumors.