title: Breast conservation in the setting of contemporary multimodality treatment provides excellent outcomes for patients with occult primary breast cancer.
abstract: OBJECTIVE
  To evaluate recurrence and survival for patients with occult (T0N+) breast cancer who underwent contemporary treatment, assessing outcomes for breast conservation and mastectomy.
  
  
  METHODS
  We performed a single-institution review of women with occult breast cancer presenting with axillary metastasis without identifiable breast tumor or distant metastasis. We excluded patients with tumors in the axillary tail or mastectomy specimen, patients with additional nonbreast cancer diagnoses, and patients with a history of breast cancer. Breast conservation was defined as axillary node dissection with radiation therapy, without breast surgery. We evaluated patient, tumor, treatment, and outcome variables. Patients were assessed for local, regional, and distant recurrences. Overall survival was calculated using the Kaplan-Meier method.
  
  
  RESULTS
  Thirty-six patients met criteria for occult breast cancer. Most of these patients (77.8 %) had N1 disease. Fifty percent of cancers (n = 18) were estrogen receptor-positive; 12 (33.3 %) were triple-negative. All patients were evaluated with mammography. Thirty-five patients had breast ultrasound (97.2 %) and 33 (91.7 %) had an MRI. Thirty-four patients (94.4 %) were treated with chemotherapy and 33 (91.7 %) with radiotherapy. Twenty-seven patients (75.0 %) were treated with breast conservation. The median follow-up was 64 months. There were no local or regional failures. One distant recurrence occurred >5 years after diagnosis, resulting in a 5-years overall survival rate of 100 %. There were no significant survival differences between patients receiving breast conservation versus mastectomy (p = 0.7).
  
  
  CONCLUSIONS
  Breast conservation-performed with contemporary imaging and multimodality treatment-provides excellent local control and survival for women with T0N+ breast cancer and can be safely offered instead of mastectomy.
authors.affiliation: Department of Surgical Oncology, The University of Texas MD Anderson Cancer Center, 1515 Holcombe Blvd., Unit 1484, Houston, TX, 77030, USA.
authors.forename: Natasha M
authors.initials: NM
authors.lastname: Rueth
authors.forename: Dalliah M
authors.initials: DM
authors.lastname: Black
authors.forename: Angela R
authors.initials: AR
authors.lastname: Limmer
authors.forename: Emmanuel
authors.initials: E
authors.lastname: Gabriel
authors.forename: Lei
authors.initials: L
authors.lastname: Huo
authors.forename: Bruno D
authors.initials: BD
authors.lastname: Fornage
authors.forename: Basak E
authors.initials: BE
authors.lastname: Dogan
authors.forename: Mariana
authors.initials: M
authors.lastname: Chavez-MacGregor
authors.forename: Min
authors.initials: M
authors.lastname: Yi
authors.forename: Kelly K
authors.initials: KK
authors.lastname: Hunt
authors.forename: Eric A
authors.initials: EA
authors.lastname: Strom
mesh_terms: D000328:Adult; D000368:Aged; D000971:Antineoplastic Combined Chemotherapy Protocols / Q000627:therapeutic use; D001943:Breast Neoplasms / Q000401:mortality / Q000473:pathology / Q000628:therapy*; D018270:Carcinoma, Ductal, Breast / Q000401:mortality / Q000473:pathology / Q000628:therapy*; D018275:Carcinoma, Lobular / Q000401:mortality / Q000473:pathology / Q000628:therapy*; D003131:Combined Modality Therapy; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008197:Lymph Node Excision; D008327:Mammography; D015412:Mastectomy, Segmental; D008875:Middle Aged; D009364:Neoplasm Recurrence, Local / Q000401:mortality / Q000473:pathology / Q000628:therapy*; D009367:Neoplasm Staging; D011379:Prognosis; D015996:Survival Rate; D016217:Ultrasonography, Mammary