Breast-Conserving Therapy (Lumpectomy with Radiation Therapy)

David R. Farley, MD
Content Author:
Lisa Qiu, Matthew Zeller DO
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Background Information: 

There are several types of surgical approaches for management of breast disease differentiated by the level of invasiveness and the anatomical structures preserved post-operatively. Modified radical mastectomy, simple mastectomy, skin-sparing mastectomy, nipple-areolar sparing mastectomy, and lumpectomy with or without sentinel lymph node biopsy are most often utilized in practice. 

Lumpectomy is the removal of the suspicious lesion without the removal of the whole breast, therefore not requiring reconstruction. It is used to remove both invasive (invasive ductal, lobular) and non-invasive cancers (DCIS, LCIS) of the breast. Lumpectomy is often performed with sentinel lymph node biopsy to assess for nodal metastasis. When combined with adjuvant radiation treatment, as is commonly practiced, lumpectomy is termed breast-conserving therapy. If patients are candidates, breast-conserving therapy is preferred to mastectomy due to the similar rates of overall survival1 and favorable cosmetic outcomes. Studies are increasingly showing better overall survival with breast-conserving therapy when compared to mastectomy without radiation.² 


Breast-conserving surgery is considered the treatment of choice for non-metastatic breast cancer when the tumor can be removed with negative margins and a favorable cosmetic outcome. If patients are not willing to undergo or have a contraindication to adjuvant radiation treatment, they may not be candidates for breast-conserving therapy.

Procedure Description: 

Breast-conserving therapy begins with the surgical removal of the primary tumor (lumpectomy). Pre-operatively, radiology may place wires defining the lesion to aid the surgeon with localization in the OR. An incision is made directly superficial to the lesion or placed circumareolar, within the inframammary fold, or along the lateral contour of the breast to improve cosmesis and allow the best access to the tumor. Regardless of the location, the incision should follow Langer’s lines. The tumor is excised and oriented for pathological evaluation with a stitch or ink to ensure negative margins. The defect is closed cosmetically. 

Attention is now turned to the sentinel lymph node biopsy. With a radiotracer probe, the sentinel node is identified, removed, and sent for pathological evaluation. 

Key Anatomy:

  • Breast tissue
  • ~Glandular and fibrous tissue
  • ~Fatty connective tissue
  • ~Areola
  • ~Nipple
  • ~Cooper’s ligaments
  • Breast boarders
  • ~Superior: Clavicle
  • ~Medial: Lateral border of sternum
  • ~Inferior: Inframammary fold
  • ~Lateral: Anterior axillary line
  • Axillary lymph nodes
  • ~Levels I, II, III
  • ~~Level I nodes are lateral/inferior to the pectoralis minor 
  • ~~Level II nodes are deep to the pectoralis minor
  • ~~Level III nodes are medial/superior to the pectoralis minor
  • Musculature
  • ~Pectoralis major 
  • ~Pectoralis minor 
  • Langer’s lines of the breast


General surgical risks:

  • Bleeding
  • Breast infection

Risks specific to lumpectomy:

  • Clinically significant seroma (6%³) 
  • ~Defined as one or more aspirations or drain placement post-operatively. 

Key Literature:

  • NSABP B-06 Randomized Controlled Trialⁱ
  • ~A randomized controlled trial comparing total mastectomy, lumpectomy, and lumpectomy plus radiation therapy in patients with tumors 4 cm or less and clinically negative lymph nodes. The study population of 1851 with clinically negative lymph nodes was followed for 20 years. No significant difference was observed in disease-free survival, distant disease-free survival, or overall survival between the three treatment groups. They found a hazard ratio of 0.94 for those who underwent lumpectomy and radiation when compared to those undergoing mastectomy. 
  • ~The authors concluded lumpectomy with radiation is an appropriate therapy for those with negative margins and good cosmetic results. 


  • The ACOSOG Z0011 (Alliance) Randomized Clinical Trial⁴
  • ~A randomized control trial of 856 women with invasive primary breast cancer, no palpable axillary lymphadenopathy and maximum 1-2 sentinel lymph nodes with metastases. In addition to lumpectomy, irradiation, and systemic therapy, two groups were treated with either sentinel lymph node dissection or axillary lymph node dissection and followed for almost 10 years to collect data on survival and recurrence of cancer. No significant difference was found between the groups, indicating that routine use of axillary dissection does not improve overall survival in breast cancer patients who meet the criteria of those in the study
  • ~These results have greatly reduced the use of axillary dissection, which has been connected to significant morbidity, in breast cancer management. 

Additional resources


  • Sabiston Textbook of Surgery: The Biological Basis of Modern Surgical Practice by Courtney M. Townsend Jr. JR. MD
  • Atlas of General Surgical Techniques: Townsend, Evers

Online resources:

  1. Fisher, B., Anderson, S., Bryant, J., Margolese, R. G., Deutsch, M., Fisher, E. R., … Wolmark, N. (2002). Twenty-Year Follow-up of a Randomized Trial Comparing Total Mastectomy, Lumpectomy, and Lumpectomy plus Irradiation for the Treatment of Invasive Breast Cancer. New England Journal of Medicine, 347(16), 1233–1241.
  2. Hwang, E. S., Lichtensztajn, D. Y., Gomez, S. L., Fowble, B., & Clarke, C. A. (2013). Survival after lumpectomy and mastectomy for early stage invasive breast cancer: The effect of age and hormone receptor status. Cancer, 119(7), 1402–1411. 
  3. Boostrom, S. Y., Throckmorton, A. D., Boughey, J. C., Holifield, A. C., Zakaria, S., Hoskin, T. L., & Degnim, A. C. (2009, January). Incidence of Clinically Significant Seroma after Breast and Axillary Surgery. Journal of the American College of Surgeons. J Am Coll Surg. 
  4. Giuliano AE, Ballman KV, McCall L, et al. Effect of Axillary Dissection vs No Axillary Dissection on 10-Year Overall Survival Among Women With Invasive Breast Cancer and Sentinel Node Metastasis: The ACOSOG Z0011 (Alliance) Randomized Clinical Trial. JAMA. 2017;318(10):918–926. doi:10.1001/jama.2017.11470