Is Axillary Assessment of Ductal Carcinoma In Situ of the Breast Necessary in All Cases?

Background: Staging of the axilla in women with ductal carcinoma in situ (DCIS) is a point of controversy. We aimed to assess whether there is a group of patients in whom axillary assessment can be avoided and whether the likelihood of underdiagnosis of infiltrating carcinoma is sufficient to justify this evaluation.

Materials And Methods: This was a multicenter, prospective, observational study of patients who were operated on between 2008 and 2018 in three Spanish hospitals, with a diagnosis by radiological or excisional biopsy of DCIS and clinically and radiologically negative axilla.

Results: A total of 530 patients with a preoperative diagnosis of DCIS were studied. An axillary assessment was performed in 77% of the patients. In 397 patients, selective sentinel lymph node biopsy was performed. Axillary involvement was found in 7.2% of all patients, which dropped to 2.15% if we only included DCIS diagnosed after a definitive anatomical pathology analysis. Underdiagnosis was correlated with the type of biopsy performed: the risk was 1.34 times as high if the biopsy was performed with a core needle. The risk of lymph node metastasis was higher when there was lymphovascular invasion and when mastectomy was performed.

Conclusions: We propose an axilla management algorithm in patients with a preoperative diagnosis of DCIS. The patients who would benefit from sentinel lymph node biopsy would be those who are not candidates for breast-conserving surgery, those with a BIRADS 5 lesion biopsied by core-needle biopsy, and those whose definitive diagnosis is lymphovascular invasion.