Medical Policy


Subject: Focused Microwave Thermotherapy for Breast Cancer
Document #: SURG.00137 Publish Date:    06/06/2018
Status: Reviewed Last Review Date:    05/03/2018


This document addresses focused microwave thermotherapy as a treatment for breast cancer. Focused microwave thermotherapy has been investigated in a number of settings, including as a treatment for primary breast cancer in conjunction with lumpectomy for early stage breast cancer and as a cytoreductive technique in conjunction with preoperative chemotherapy in locally advanced breast cancer.

Note: For additional information see the following topics:

Position Statement

Investigational and Not Medically Necessary:

Focused microwave thermotherapy is considered investigational and not medically necessary as a treatment for breast cancer.


There is limited published clinical trial data regarding focused microwave thermotherapy for the treatment of breast cancer. Gardner and colleagues (2002) reported the results of a phase I and II clinical trial of 10 individuals and concluded the procedure was technically feasible. Vargas and colleagues (2004) reported a dose-finding study in 25 individuals, performed as part of an Investigational Device Exemption (IDE) trial. Study subjects underwent microwave thermotherapy at various doses before undergoing surgical resection of breast cancer to determine whether the use of thermotherapy before breast conserving surgery (BCS) could potentially reduce the incidence of positive surgical margins, and thus the need for re-excision. The authors concluded microwave thermotherapy caused tumor necrosis and could be performed safely with minimal morbidity. The degree of tumor necrosis is a function of the thermal dose.

A review of ablative therapies including microwave thermotherapy for the treatment of malignant diseases of the breast (Huston, 2005) reported that long-term follow-up data are lacking regarding local effects on the surrounding breast tissue or recurrence rates. The authors concluded, "The challenge will lie in the ability to identify multifocal disease and in situ carcinoma as well as to ensure complete and effective eradication."

Dooley and colleagues (2010) reviewed results of four clinical studies evaluating focused microwave thermotherapy for preoperative treatment of invasive breast cancer. In the initial phase I study, 8 of 10 (80%) participants receiving one low dose of focused microwave thermotherapy prior to mastectomy had a partial tumor response. Partial tumor response was identified by ultrasound measurements of tumor volume reduction or by pathologic cell kill. In the phase II study, the focused microwave thermotherapy dose was increased to stimulate 100% pathologic tumor cell kill for invasive carcinoma prior to BCS. In a randomized trial comprised of participants with early-stage invasive breast cancer, it was reported that of those who had received preoperative focused microwave thermotherapy at ablative temperatures, 0 of 34 (0%) had positive tumor margins, while positive margins were found in 4 of 41 (9.8%) of participants receiving only BCS. In a randomized trial of participants with large breast tumors, the median reduction of tumor volume based on ultrasound measurements was 88.4% (n=14) for those who received focused microwave thermotherapy and chemotherapy, as compared with 58.8% (n=10) reduction in those who received chemotherapy alone. Study limitations include small numbers of participants.

The National Comprehensive Cancer Network® (NCCN) (2018) Clinical Practice Guidelines in Oncology document for the treatment of breast cancer does not address the use of focused microwave thermotherapy as a treatment option.

There is insufficient evidence in the peer-reviewed literature documenting the safety and efficacy of microwave thermotherapy for the treatment of breast cancer. Published clinical studies have not demonstrated that the use of microwave thermotherapy results in improved health outcomes among individuals with breast cancer.


According to the American Cancer Society (ACS), breast cancer is the most common cancer among American women, except for skin cancers. About 1 in 8 (12%) women in the United States will develop invasive breast cancer during their lifetime. The ACS estimates that for American women in 2018 there will be:

Once breast cancer has been detected, there are several treatment options available depending upon the severity of the disease. Removal of a single tumor, referred to as a lumpectomy, is usually limited to early stage cancers. Mastectomy, or removal of the affected breast, is also an option.

Focused microwave thermotherapy has been investigated as a type of heat therapy for treating either primary breast cancer in conjunction with lumpectomy in individuals with early stage breast cancer or as a technique to reduce tumor size in conjunction with preoperative chemotherapy in those with advanced breast cancer. 

Microwave thermotherapy works on the principle that microwave energy excites water molecules to create heat. During this procedure, the breast to be treated is compressed between two microwave emitters and a surgical probe is placed within the breast to monitor the temperature of the tissue. When activated, the emitters cover a large volume of breast tissue with microwave energy. In breast cancer, the tumor tissue contains a higher volume of water than the surrounding tissue. The cancerous tissue heats more rapidly and is destroyed while leaving the healthy tissue relatively undisturbed.

If determined to be effective, the focused microwave thermotherapy could function similarly to the role of whole breast irradiation therapy after BCS, that is, by destroying microscopic residual cancer cells. In individuals with locally advanced primary breast cancer, focused microwave thermotherapy may sufficiently reduce the size of the tumor to allow a less invasive surgical procedure to be performed. However, at this time there is insufficient evidence in the published literature to support the use of focused microwave thermotherapy as a treatment for breast cancer.


Carcinoma in situ: Non-invasive and is the earliest form of breast cancer.

Cytoreductive: To reduce the number of cells in a lesion, usually a malignancy.


The following codes for treatments and procedures applicable to this document are included below for informational purposes. Inclusion or exclusion of a procedure, diagnosis or device code(s) does not constitute or imply member coverage or provider reimbursement policy. Please refer to the member's contract benefits in effect at the time of service to determine coverage or non-coverage of these services as it applies to an individual member.

When services are Investigational and Not Medically Necessary:
For the following procedure codes or when the code describes a procedure indicated in the Position Statement section as investigational and not medically necessary.





Unlisted procedure, breast [when specified as focused microwave thermotherapy]




ICD-10 Procedure



For the following codes when specified as focused microwave thermotherapy:


Destruction of right breast, external approach


Destruction of left breast, external approach


Destruction of bilateral breast, external approach



ICD-10 Diagnosis



All diagnoses


Peer Reviewed Publications:

  1. Dooley WC, Vargas HI, Fenn AJ, et al. Focused microwave thermotherapy for preoperative treatment of invasive breast cancer: a review of clinical studies. Ann Surg Oncol. 2010; 17(4):1076-1093.
  2. Gardner RA, Vargas HI, Block JB, et al. Focused microwave phased array thermotherapy for primary breast cancer. Ann Surg Oncol. 2002; 9(4):326-332.
  3. Huston TL, Simmons RM. Ablative therapies for the treatment of malignant diseases of the breast. Am J Surg. 2005; 189(6):694-701.
  4. Mauri G, Sconfienza LM, Pescatori LC, et al. Technical success, technique efficacy and complications of minimally-invasive imaging-guided percutaneous ablation procedures of breast cancer: A systematic review and meta-analysis. Eur Radiol. 2017; 27(8):3199-3210.
  5. Vargas HI, Dooley WC, et al. Focused microwave phased array thermotherapy for ablation of early state breast cancer: results of thermal dose escalation. Ann Surg Oncol. 2004; 11(2):139-146.

Government Agency, Medical Society, and Other Authoritative Publications:

  1. American Cancer Society (ACS). Breast Cancer Facts & Figures. 2015-2016. Available at: Accessed on March 08, 2018.
  2. NCCN Clinical guidelines in Oncology (NCCN Guidelines®). © 2018 National Comprehensive Cancer Network, Inc. For additional information visit the NCCN website: Accessed on March 09, 2018. Breast Cancer (V.4.2017). Revised February 07, 2018.
Websites for Additional Information
  1. American Cancer Society. About Breast Cancer. Available at: Accessed on March 09, 2018.
  2. U.S. National Library of Medicine. MedlinePlus Breast Cancer. Last updated on March 06, 2018. Available at: Accessed on March 09, 2018.

Breast Cancer
Focused Microwave Phase Array Thermotherapy
Focused Microwave Thermotherapy (FMT)
Microwave Thermotherapy

The use of specific product names is illustrative only. It is not intended to be a recommendation of one product over another, and is not intended to represent a complete listing of all products available.

Document History






Medical Policy & Technology Assessment Committee (MPTAC) review.



Hematology/Oncology Subcommittee review. Updated References and Websites sections.



The document header wording updated from “Current Effective Date” to “Publish Date.” Updated Coding section with 01/01/2018 CPT changes; removed 0301T deleted 12/31/2017, added 19499.



MPTAC review.



Hematology/Oncology Subcommittee review. Updated Description/Scope, Rationale, References and Websites sections.



MPTAC review.



Hematology/Oncology Subcommittee review. Updated Rationale, Background/Overview, References and Websites for Additional Information sections. Removed ICD-9 codes from Coding section.



MPTAC review.



Hematology/Oncology Subcommittee review. Updated Rationale, Background/Overview and References sections.



MPTAC review.



Hematology/Oncology Subcommittee review. Updated Rationale and References sections.



MPTAC review.



Hematology/Oncology Subcommittee review. Initial document development.