Oncologic Outcomes After Treatment for MRI Occult Breast Cancer (pT0N+)

Abstract

Background Studies assessing outcomes in occult breast cancer have often included women treated before the routine use of MRI. We undertook to examine outcomes in patients presenting with axillary adenopathy and no primary detectable on MRI or other imaging modalities. Methods All patients with axillary nodal metastases consistent with breast carcinoma, and no detectable breast primary on physical exam, mammography, or MRI treated between 1/1/1996 and 6/30/2011 were identified from an institutional database. Data was collected on local, regional, and distant recurrences. Results Thirty-eight patients were identified. Modified radical mastectomy (MRM) was performed in 13, while 25 underwent axillary dissection (ALND) and whole-breast radiotherapy (WBRT). Most women had pathological N1 disease (median number of positive nodes 2 [MRM cohort] and 3 [ALND+WBRT cohort], p=0.38). All patients received chemotherapy, with 30 of the 38 patients (79%) treated receiving an anthracycline and taxane. Regional nodal radiation was used in 60% of those with ALND+WBRT and in all of the 46% of MRM patients who received chest wall radiotherapy. At a median follow up of 7 years, there were no nodal recurrences. Two patients treated with ALND+WBRT developed in-breast recurrences; none in the MRM group developed local recurrence. The proportion that developed distant disease was similar between the MRM cohort (1 of 13) and the ALND+WBRT cohort (2 of 25). Conclusion Breast cancer presenting as axillary adenopathy but no detectable primary is rare. Breast conservation with WBRT is a viable option for patients diagnosed with occult breast cancer and a negative preoperative MRI.

Breast MRI: State of the Art

“…Because therapy may reduce enhancement in breast lesions, during and after chemotherapy, evaluation of late phase enhancement may still be important. negative, radiation therapy to the ipsilateral breast is as safe as mastectomy, and therefore MRI in this setting may prevent unnecessary mastectomies (154,155).…”

Outcome of breast-conserving treatment for axillary lymph node metastasis from occult breast cancer with negative breast MRI

“…Breast MRI has only recently become increasingly utilized as a routine tool in diagnosing OBC. A recent study showed favorable prognosis in MRI-OBC patients after BCT [ 14 ], with 4 recurrences among 25 patients (2 in the breast and 2 in distant organs), and a 5-year DFS of approximately 80%. We also found a favorable outcome after BCT in this study.…”

“…[ 13 ] Single institution 36 2000–2011 91.7% ALND (91.7%), TM (25.0%), no breast surgery (75.0%) Breast (91.7%), RNI (77.8%) 0.0% 5-yr OS 100.0% N1 (77.8%), N2 (16.7%), N3 (5.6%) McCartan et al. [ 14 ] Single institution 38 1996–2011 100.0% ALND + WBRT (65.8%) ALND + TM (34.2%) Breast (100%), RNI (55.3%), chest wall (46.2%) 8% (only in WBRT group) 77.0% for TM, 10-yr DFS 67.0% for WBRT N1 (57.9%), N2 (31.6%), N3 (10.5%) The present study Multicenter 66 2001–2013 100.0% ALND + BCT (100.0%) Breast (18.2%), Breast + RNI (75.7%), RNI (6.1%) 9.1% 92.1% at 5-yrs, DFS 80.6% at 10-yrs Included 12 patients with SCN or IMN metastasis Abbreviation: MRI, magnetic resonance imaging; RT, radiotherapy; ALND, axillary lymph node dissection; TM, total mastectomy NR, not reported; LR, locoregional; NCDB, the National Cancer Database of the United States; OS, overall survival; SEER, the Surveillance, Epidemiology and End Results Program; BCS, breast-conserving surgery; RNI, regional lymph node irradiation; DFS, disease-free survival; SCN, supraclavicular lymph nodes. a years of patient’s accrual or periods of study inclusion.…”

“…Given that advanced imaging modalities like breast magnetic resonance imaging (MRI) improve the ability to identify breast tumors [ 11 , 12 ], the prognosis of OBC could be affected if these modalities were utilized in the diagnosis. Prior studies have investigated outcome after BCT in patients with OBC diagnosed by contemporary imaging modalities [ 13 , 14 ], but these analyzed only a small number of patients and did not provide convincing evidence regarding prognosis and failure pattern. In this multicenter study, we aimed to investigate the prognosis and failure pattern after BCT in female patients with OBC with negative breast MRI (MRI-OBC).…”

Occult breast cancer: Where are we at?

“…The only review of pOBC patients comparing mastectomy to whole breast RT (WBRT) has been performed at Memorial Sloan Kettering Cancer Center (MSKCC) by McCartan et al. (2017) [ 39 ]. Thirty-eight patients were treated as per current National Comprehensive Cancer Network (NCCN) guidelines with either ALND and WBRT (n = 25) or ALND and mastectomy (n = 13).…”