Primary Treatment

Local-regional treatment

Stage I, II, IIIA, and operable IIIC breast cancer often requires a multimodality approach to treatment. Irrespective of the eventual procedure selected, the diagnostic biopsy and surgical procedure that will be used as primary treatment should be performed as two separate procedures. In many cases, the diagnosis of breast carcinoma using core needle biopsy or fine-needle aspiration cytology may be sufficient to confirm malignancy. After the presence of a malignancy is confirmed and histology is determined, treatment options should be discussed with the patient before a therapeutic procedure is selected. The surgeon may proceed with a definitive procedure that may include biopsy, frozen section confirmation of carcinoma, and the surgical procedure elected by the patient. Estrogen-receptor (ER) and progesterone-receptor (PR) protein status should be determined for the primary tumor.[1] Additional pathologic characteristics, including grade, proliferative activity, and human epidermal growth factor receptor 2 (HER2/neu) status, may also be of value.[2-5]

Options for surgical management of the primary tumor include breast-conserving surgery plus radiation therapy, mastectomy plus reconstruction, and mastectomy alone. Surgical staging of the axilla should also be performed. Survival is equivalent with any of these options as documented in randomized prospective trials (including the European Organization for Research and Treatment of Cancer’s trial [EORTC-10801]).[6-13] Selection of a local therapeutic approach depends on the location and size of the lesion, analysis of the mammogram, breast size, and the patient’s attitude toward preserving the breast. The presence of multifocal disease in the breast or a history of collagen vascular disease are relative contraindications to breast-conserving therapy.[14] A retrospective study of 753 patients who were divided into three groups based on receptor status (ER- or PR-positive; ER- and PR-negative but HER2/neu-positive; and ER-, PR-, and HER2/neu-negative [triple-negative]) found no differences in disease control within the breast in patients treated with standard breast-conserving surgery; however, there are not yet substantive data to support this finding.[15]

All histologic types of invasive breast cancer may be treated with breast-conserving surgery plus radiation therapy.[16] The rate of local recurrence in the breast with conservative treatment is low and varies slightly with the surgical technique used (e.g., lumpectomy, quadrantectomy, segmental mastectomy, and others). Whether completely clear microscopic margins are necessary is debatable.[17-19]

Retrospective studies have shown the following examples of tumor characteristics to correlate with a greater likelihood of finding persistent tumor on re-excision:

  • Large tumors (T2 lesions).
  • Positive axillary nodes.
  • Tumors with an extensive intraductal component.[20]
  • Palpable tumors.
  • Lobular histology.

Patients whose tumors have these characteristics may benefit from a more generous initial excision to avoid the need for a re-excision.[21,22]

Radiation therapy (as part of breast-conserving local therapy) consists of postoperative external-beam radiation therapy (EBRT) to the entire breast with doses of 45 Gy to 50 Gy, in 1.8 Gy to 2.0 Gy daily fractions over a 5-week period. Shorter hypofractionation schemes achieve comparable results.[23-25] A further radiation boost is commonly given to the tumor bed. Two randomized trials conducted in Europe have shown that using boosts of 10 Gy to 16 Gy reduces the risk of local recurrence from 4.6% to 3.6% at 3 years (P = .044),[26][Level of evidence: 1iiDiii] and from 7.3% to 4.3% at 5 years (P < .001), respectively.[27][Level of evidence: 1iiDiii] If a boost is used, it can be delivered either by EBRT, generally with electrons, or by using an interstitial radioactive implant.[28]

The age of the patient should not be a determining factor in the selection of breast-conserving treatment versus mastectomy. A study has shown that treatment with lumpectomy and radiation therapy in women 65 years and older produces survival and freedom-from-recurrence rates similar to those of women younger than 65 years.[29] Whether young women with germ-line mutations or strong family histories are good candidates for breast-conserving therapy is not certain. Retrospective studies indicate no difference in local failure rates or overall survival (OS) when women with strong family histories are compared with similarly treated women without such histories.[30,31][Level of evidence: 3iiiDii] The group with a positive family history, however, does appear more likely to develop contralateral breast cancer within 5 years.[30] This risk for contralateral tumors may be even greater in women who are positive for BRCA1 and BRCA2 mutations.[32][Level of evidence: 3iiiDii] Because of the available evidence indicating no difference in outcome, women with strong family histories should be considered candidates for breast-conserving treatment. For women with germ-line mutations in BRCA1 andBRCA2, further study of breast-conserving treatment is needed.

Breast-conserving surgery alone without radiation therapy has been compared with breast-conserving surgery followed by radiation therapy in six prospective randomized trials (including the National Surgical Adjuvant Breast and Bowel Project’s trial [NSABP-B-06] and the Cancer and Leukemia Group B’s trial [CLB-9343]).[6,33-37] In two of these trials, all patients also received adjuvant tamoxifen.[36,37] Every trial demonstrated a lower in-breast recurrence rate with radiation therapy, and this effect was present in all patient subgroups. In some groups, for example, women with receptor-positive small tumors [36] and those older than 70 years,[38] the absolute reduction in the rate of recurrence was small (<5%). The limited impact of radiation therapy in this group of women was also reported in a confirmatory observational study looking at in-breast control rates using the Surveillance, Epidemiology, and End Results (SEER)-Medicare database.[39] The impact of radiation therapy on local control was additionally clarified by showing that healthy women aged 70 to 79 years were most likely to benefit from radiation therapy (number needed to treat [NNT] to prevent one event = 21–22 patients) when compared to women aged 80 years or older or to those who have comorbidities (NNT = 61–125 patients).[39] The administration of radiation therapy may be associated with short-term morbidity, inconvenience, and potential long-term complications.[38]

Axillary lymph node surgery

The axillary lymph nodes should be staged to aid in determining prognosis and therapy. Sentinel lymph node (SLN) biopsy is the initial standard axillary staging procedure performed in women with invasive breast cancer. The SLN is defined as any node that receives drainage directly from the primary tumor, therefore, allowing for more than one SLN, which is often the case. Studies have shown that the injection of technetium-labeled sulfur colloid, vital blue dye, or both around the tumor or biopsy cavity, or in the subareolar area, and subsequent drainage of these compounds to the axilla results in the identification of the SLN in 92% to 98% of patients.[40,41] These reports demonstrate a 97.5% to 100% concordance between SLN biopsy and complete axillary lymph node dissection (ALND).[42-45]

A multicenter randomized phase III trial of 5,611 patients randomly assigned to either SLN plus ALND or to SLN resection alone with ALND only if the SLNs were positive showed no detectable difference in OS, disease-free survival (DFS), and regional control. OS was 91.8% versus 90.3% in the SLN plus ALND and SLN alone, respectively (P = .12).[46][Level of evidence: 1iiA]

Similarly, a single-center randomized trial of 532 patients with T1 carcinomas undergoing either SLN biopsy plus complete axillary dissection or SLN biopsy alone showed, after a median follow-up of 78 months, no difference in 5-year DFS (92.9% in the SLN biopsy without routine axillary dissection group vs. 88.9% in patients having axillary dissection irrespective of SLN findings, P = .1).[47][Level of evidence: 1iiDii]

The reported false-negative rates of SLN biopsy using axillary node dissection as the gold standard range from 0% to 15% with an average of 8.8%.[48] The success rate varies with the surgeon’s experience and with the primary tumor characteristics. In general, studies have restricted the use of SLN biopsy to women with T1 and T2 disease, without evidence of multifocal involvement or clinically positive lymph nodes. SLN biopsy alone is associated with less morbidity than axillary lymphadenectomy. In a randomized trial of 1,031 women that compared SLN biopsy followed by axillary dissection when the SLN was positive with axillary dissection in all patients, quality of life at 1 year (as assessed by the frequency of patients experiencing a clinically significant deterioration in the Trial Outcome Index of the Functional Assessment of Cancer Therapy-Breast scale) was superior in the SLN biopsy group (23% vs. 35% deteriorating in the SLN biopsy vs. axillary dissection groups, respectively; P = .001).[49][Level of evidence 1iiC] Arm function was also better in the SLN group. The NSABP-B-32 (NCT00003830) trial, a randomized study of 5,611 women, found the same results with respect to accuracy and technical success.[50] Based on this body of evidence, SLN biopsy is the standard initial surgical staging procedure of the axilla for women with invasive breast cancer.

A multicenter, randomized clinical trial sought to determine whether ALND is required after an SLN biopsy reveals an SLN metastasis of breast cancer.[51] This phase III noninferiority trial planned to randomly assign 1,900 women with clinical T1–T2 invasive breast cancer without palpable adenopathy and with one to two SLNs containing metastases identified by frozen section to undergo ALND versus no further axillary treatment. All patients underwent lumpectomy, tangential whole-breast irradiation, and appropriate systemic therapy, and OS was the primary endpoint. Because of enrollment challenges, a total of 891 women out of a target enrollment of 1,900 women were randomly assigned to one of the two treatment arms. At a median follow-up of 6.3 years, 5-year OS was 91.8% (95% CI, 89.1%–94.5%) with ALND and 92.5% (95% CI, 90.0–95.1%) with SLN biopsy alone. The secondary endpoint of 5-year disease-free survival (DFS) was 82.2% (95% CI, 78.3%–86.3%) with ALND and 83.9% (95% CI, 80.2%–87.9%) with SLN biopsy alone.[51][Level of evidence: 1iiA] On the basis of the results of this trial, the medical necessity of ALND after a positive SLN biopsy in patients with limited SLN-positive breast cancer treated with breast conservation, radiation, and systemic therapy is called into question.

For patients who require an ALND, the standard evaluation usually involves only a level I and II dissection, thereby removing a satisfactory number of nodes for evaluation (i.e., 6–10 at least), while reducing morbidity from the procedure. Several groups have attempted to define a population of women in whom the probability of nodal metastasis is low enough to preclude axillary node biopsy. In these single-institution case series, the prevalence of positive nodes in patients with T1a tumors ranged from 9% to 16%.[52,53] In another series, the incidence of axillary node relapse in patients with T1a tumors treated without ALND was 2%.[54][Level of evidence: 3iiiA] Because the axillary node status remains the most important predictor of outcome in breast cancer patients, insufficient evidence is available to recommend that lymph node staging can be omitted in most patients with invasive breast cancer.

Breast reconstruction

For patients who opt for a total mastectomy, reconstructive surgery may be used at the time of the mastectomy (i.e., immediate reconstruction) or at some subsequent time (i.e., delayed reconstruction).[55-58] Breast contour can be restored by the submuscular insertion of an artificial implant (saline-filled) or a rectus muscle or other flap. If a saline implant is used, a tissue expander can be inserted beneath the pectoral muscle. Saline is injected into the expander to stretch the tissues for a period of weeks or months until the desired volume is obtained. The tissue expander is then replaced by a permanent implant. (Visit the FDA’s Web site for more information on breast implants.) Rectus muscle flaps require a considerably more complicated and prolonged operative procedure, and blood transfusions may be required.

Following breast reconstruction, radiation therapy can be delivered to the chest wall and regional nodes either in the adjuvant setting or if local disease recurs. Radiation therapy following reconstruction with a breast prosthesis may affect cosmesis, and the incidence of capsular fibrosis, pain, or the need for implant removal may be increased.[59]