Table 1.

Patient demographics: At initiation of surveillance all women had biopsy proven ER(+) DCIS. Premenopausal women were prescribed tamoxifen. Postmenopausal women were prescribed an aromatase inhibitor. For the three women who discontinued endocrine therapy due to side effects, total months on therapy for each patient were: Patient 5–13 months; Patient 8–1.4 months; Patient 9–8.7 months.

Study ID	Age at diagnosis	Menopausal Status	Endocrine therapy	Initial DCIS Grade	Radiographic extent of DCIS at diagnosis
1	41	Pre	Tamoxifen	Int	MMGa: No findings MRI: multifocal 5–9 mm enhancing lesions
2	42	Pre	Tamoxifen	Low	MMG: 7 cm Ca2+
3	46	Pre	Tamoxifen	Int	MMG: 4.4 cm Ca2+
4	47	Pre	Tamoxifen	Low	MMG: 6 cm Ca2+
5	47	Pre	Tamoxifen: discontinued	Int	MMG: 4 cm Ca2+
6	48	Pre	Tamoxifen	Low	MMG: 8 cm Ca2+
7	48	Pre	Tamoxifen	High	MMG: Multifocal up to 3 cm Ca2+
8	50	Pre	Tamoxifen: discontinued	Low	MMG: no MMG available MRI: up to 4.4 cm abnormal enhancement
9	52	Pre	Tamoxifen: discontinued	Int	MMG: 7 cm Ca2+
10	55	Post	Letrozole	Int	MMG: 9 cm Ca2+
11	56	Post	Letrozole	Int	MMG: 2 cm Ca2+
12	58	Post	Letrozole	High	MMG: 2.5 cmCa2+
13	60	Post	Arimidex	Int	MMG: Multicentric in 2 quadrants; largest focus 2.5 cm
14	71	Post	Letrozole	Int	MMG: 1.6 cm Ca2+