Population‐based analysis of occult primary breast cancer with axillary lymph node metastasis

Abstract

BACKGROUND Single-institution data suggest that treatment with radiation and axillary lymph node dissection (ALND) may be an appropriate alternative to mastectomy for T0N+ breast cancer. Population-based multi-institutional data supporting this approach are lacking. METHODS The cause-specific survival (CSS) and overall survival (OS) of women with T0N+M0 ductal, lobular, or mixed breast cancer in the Surveillance, Epidemiology, and End Results database from 1983 to 2006 were analyzed. Groups were defined as: 1) no ALND, mastectomy, or RT (observation); 2) ALND only; 3) mastectomy plus ALND with or without postmastectomy radiation (Mast); and 4) breast-conserving therapy (BCT) with ALND and radiation (BCT). RESULTS In total, 750 of 770,030 patients with breast cancer had T0N+ M0 disease (incidence, 0.10%), and 596 of those patients underwent ALND (79.5%). Patients who underwent Mast or BCT (n = 470) had a 10-year OS rate of 64.9% compared with 58.5% for patients who underwent ALND only (n = 126; P = .02) and 47.5% for patients who underwent observation only (n = 94; P = .04). The 10-year CSS rate was 75.7% for patients who underwent BCT versus 73.9% for patients who underwent Mast (P = .55). In multivariate analysis of CSS for patients who underwent Mast or BCT, the following factors were correlated with an unfavorable outcome: positive estrogen receptor status (hazard ratio [HR], 0.48; 95% confidence interval [CI], 0.24–0.96; P = .04), ≥10 positive lymph nodes (HR, 5.7; 95%CI, 2.4–13.4; P ≤ .01), and <10 resected lymph nodes (HR, 42.9; 95%CI, 1.2–7.1; P = .02). Mast did not improve CSS compared with BCT (HR, 1.09; 95%CI, 0.57–2.1; P = .79). CONCLUSIONS Definitive locoregional treatment with either Mast or BCT improved the outcome of patients with T0N+breast cancer, and no difference in survival was observed between the treatments.

Occult Breast Cancer: Is it Time to Minimize Surgical Intervention?

“…A broad spectrum of treatment choices has been proposed, ranging from surveillance only to total modified mastectomy with radiotherapy and adjuvant or neoadjuvant systemic therapy [2]. Worldwide, surgical treatment continues to be the preferred treatment for OBC, with total mastectomy being the most commonly adopted treatment [3,4]. Observational studies suggest that whole breast radiotherapy (WBRT) is a reasonable and safe alternative, perhaps even offering a better prognosis for the treatment of OBC [5].…”

The Research Progress of Occult Breast Cancer

“…There was no significant difference in the 10 year survival rate between the modified radical mastectomy group and the breast conserving 1 group, but breast conserving 2 group was significantly lower than those two groups. Breast conserving surgery should be used cautiously (Walker et al, 2010) for patients with diffuse growth of OBC. There was no significant difference in total survival rate and disease-free survival rate between ALND+mastectomy, ALND+XRT and ALND alone (Wang et al, 2013).…”

Case 27-2012

“…12 This phenomenon appears to occur in 0.1 to 0.4% of all breast cancers. [13][14][15] However, much of the available data antedate the availability of breast MRI; with contemporary imaging, the incidence is most likely lower. Without evidence of distant metastatic disease, management in this case is the same as that for early-stage breast cancer.…”

“…16 Several retrospective studies of patients presenting with an axillary-node metastasis without evidence of a primary breast tumor indicate a significant survival benefit associated with treatment of the breast and axillary dissection, as compared with either observation or axillary dissection with no treatment to the breast. [13][14][15] Survival among patients without treatment to the breast ranges from 15 to 50% at 10 years. With treatment (either irradiation or mastectomy), the 10-year survival rate is approximately 65%.…”