The Impact of Preoperative Breast MRI in Patients With Breast Cancer Selected for Breast Conserving Surgery
Condition: Breast Cancer
MeSH terms: Breast Neoplasms
Study type: Observational

Summary: 
      The purpose of this prospective observational study is to evaluate the impact of preoperative
      breast MRI in patients with breast cancer selected for breast- conserving surgery. MRI is a
      more sensitive radiological modality than mammography and ultrasonography. Patients with
      small breast cancers are, based on conventional modalities, selected for breast-conserving
      surgery. If preoperative breast MRI reveal additional lesions in the breasts, and malignancy
      is confirmed histopathologically, this finding leads to a change of surgical method to
      mastectomy.
    

Detailed description: 
      The aim of the study is to evaluate the impact of preoperative breast MRI on primary surgical
      treatment in a highly specialized multidisciplinary breast cancer clinic. The clinic serves a
      population of 237.000. The diagnostic tools routinely used are conventional mammography,
      ultrasound with core needle biopsy, and clinical examination including palpation of breast
      and axillary nodes. If indicated, the examination includes ultrasound examination and fine
      needle biopsy of axillary glands. We offer all patients selected for breast-conserving
      surgery preoperative breast MRI.

      We include consecutively breast cancer lesions in women aged 35-75 in a prospective study,
      collecting data from January 2009 to December 2010. The patients are all selected for
      breast-conserving surgery based on the criteria recommended by the Norwegian Breast Cancer
      Group. That is, tumor ≤ 4 cm, or acceptable tumor:breast ratio, and age > 35. Multifocal
      lesions, defined as more than one tumor > 1 cm apart, size of tumor > 4 cm, or a large
      tumor:breast ratio, extensive ductal carcinoma in situ (DCIS), or known genetic disposition
      for breast cancer, indicates mastectomy according to these criterias. In addition, when
      postoperative radiation therapy is contraindicated, mastectomy is indicated. If the patients
      fill the criteria for breast-conserving surgery, they are offered preoperative breast MRI and
      included in the study. Patients who either choose mastectomy, or does not get a breast MRI
      for technical reasons, are excluded from the study. Two experienced breast radiologists
      evaluate the breast MRIs, and three experienced breast radiologists study the mammographies
      and perform the ultrasound examinations and biopsies. All additional MRI findings are
      examined by ultrasound-guided biopsy and given a histological diagnose before it influence
      the surgical method.

      A formal application has been presented to the regional ethical commitee. Since this is an
      observational study of established practice, the commitee replied that approval was not
      required.
    

Observational model: Cohort
Time perspective: Prospective
Sampling method: Probability Sample
Study population: 
        Patients are selected from screening or they are referred to the Breast Diagnostic Clinic
        for clinical symptoms. The clinic serves a population of 237.000 in Nordland county,
        Norway. Patients selected for breast-conserving surgery based on conventional radiological
        examination, that is bilateral mammography and ultrasonography with biopsy, are
        consecutively included in the study and offered preoperative breast MRI.
      
Keywords: Breast cancer; Preoperative breast MRI; Breast-conserving surgery; Mastectomy; Prospective study