Currently, there is no standard recommendation for using imaging studies to check patients for breast cancer recurrence who have been treated with mastectomy. The investigator proposes performing in-office ultrasound examinations of these patients to determine if this would be helpful in identifying an expected 5-7% of patients with breast cancer recurrences following mastectomy.

The investigator hypothesizes that surgeon-directed ultrasound is a feasible, accurate, and cost-effective strategy for local recurrence surveillance in breast cancer patients after mastectomy. Toward examining these hypotheses, the investigators propose the following Specific Aims:

Aim I: To determine the number of breast cancer recurrences following mastectomy detected by surgeon-performed ultrasound.

Aim II: To determine the sensitivity and specificity of surgeon-performed ultrasound for the detection of post-mastectomy breast cancer recurrence.

Aim III: To estimate the cost of performing surgeon-directed ultrasound for the detection of post-mastectomy breast cancer recurrence from the perspective of a third party payer relative to standard surveillance alone.

Inclusion Criteria:

• must be ≥ 18 years of age.
• histologic diagnosis of invasive (ductal or lobular) or in situ (ductal) breast cancer (American Joint Committee on Cancer, 7th edition stage 0, I, II, III, or IV) -previously treated with mastectomy

Exclusion Criteria:

• pregnant or breast feeding.
• cannot tolerate lying supine for breast ultrasound examination.
• mastectomy for lobular carcinoma in situ, atypical ductal hyperplasia, or extensive microcalcifications in the absence of concurrent DCIS or invasive breast cancer