Supplementary Material 1: Dictionary of LATE or CHRONIC Side effects (based on consensus amongst breast oncology specialists at our institution, might vary based on institution)

Surgery:

Lumpectomy: breast pain/discomfort, skin changes, lymphedema, tingling or numbness

Mastecomy: breast pain/discomfort, lymphedema, skin changes, tingling or numbness

Sentinel lymph node biopsy: lymphedema, skin changes, tingling or numbness

Axillary lymph node dissection: lymphedema, skin changes, tingling or numbness

Chemotherapy:

Mitoxantrone, Gemcitabine, nab-paclitaxel: incorrect answer as no patients treated with drug(s)

Epirubicin: infertility or menopause*, heart problems, leukemia

Carboplatin: infertility or menopause*, neuropathy

Doxorubicin: infertility or menopause*, heart problems, leukemia

5-FU: infertility or menopause*

Methotrexate: infertility or menopause*, lung damage, neuropathy

Docetaxel: infertility or menopause*, neuropathy

Cyclophosphamide: infertility or menopause*, leukemia

Paclitaxel: infertility or menopause*, neuropathy

Trastuzumab: heart problems

Other: nothing coded

Radiation:

R side: breast pain/discomfort, fragile ribs, lung damage, angiosarcoma, skin changes, tingling or numbness of the arm

L side: heart problems, breast pain/discomfort, fragile ribs, lung damage, angiosarcoma, skin changes, tingling or numbness of the arm

Axillary: lymphedema, angiosarcoma, skin changes, tingling or numbness of the arm

Endocrine Therapy:

Tamoxifen or Raloxifene: blood clots, hot flashes, uterine cancer

Anastrazole, Exemestane, Letrozole or GNRH agonists: hot flashes, low bone density, vaginal dryness, joint pain/arthritis

*menopause or infertility only accepted as correct answer if patient was premenopausal at diagnosis

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