Just been diagnosed with breast cancer? You're not alone, and there is a clear path forward.

Hearing the words "breast cancer" can turn your world upside down. Take a breath. Breast cancer is one of the most studied cancers, and treatment keeps getting better and more personal. Your care team will look closely at your cancer and build a plan that fits you. Here you'll find clear, friendly guides for you and your family, one step at a time.

Updated September 30, 2026

In an emergency, call 9-1-1 or your local emergency number.

Start here

Your first 30 days: a checklist

Save the phone number of your cancer centre, including its 24-hour line, and your nurse navigator if you have one.
Ask for a copy of your pathology report, and ask your team to explain your cancer type, grade and stage.
Bring a family member or friend to appointments, and write down questions before you go.
Ask whether genetic testing is right for you, and whether any clinical trials might fit.
If you might want children in the future, ask about fertility options before treatment starts.
Keep a list of all your medicines, vitamins and supplements, and share it with your team.
Move a little every day, eat as well as you can, and rest when you need to.
Tell your team if you feel low, worried or can't sleep for more than two weeks. Support is part of care.

Your first weeks after a cancer diagnosis: A calm, step-by-step guide to the first weeks after being told you have cancer: getting organized, understanding your diagnosis, planning treatment and finding support. (6 min read)

Understand it

Breast Cancer, Explained: a longer guide for you and your family (video coming soon)
Cancer Screening, Explained: finding problems before they start (video, 4:39)

Understanding breast cancer: types, stages and tests: What breast cancer is, what hormone receptors and HER2 mean, how stage and grade are described, and the tests you may have, in plain language. (6 min read)

Your treatment

Cancer Surgery, Explained: removing the cancer, and getting ready (video coming soon)
Radiation Therapy, Explained: focused energy aimed at cancer cells (video coming soon)
Chemotherapy, Explained: medicines that travel through your body (video coming soon)
AC-T Chemotherapy: what to expect, cycle by cycle (video coming soon)
Hormone Therapy, Explained: cutting off a cancer's fuel (video coming soon)
Endocrine Therapy for Breast Cancer: hormone-blocking pills, and living well on them (video coming soon)
Targeted Therapy and Biologics: medicines aimed at a cancer's weak spots (video coming soon)
Immunotherapy and Checkpoint Inhibitors: helping your immune system fight cancer, and side effects to report (video coming soon)

Breast cancer treatment options, explained: A plain-language guide to breast cancer surgery, radiation, chemotherapy, hormone therapy, HER2-targeted therapy and immunotherapy, and how your team chooses what fits you. (5 min read)
Clinical trials explained: What cancer clinical trials are, how the phases work, what randomization and placebos mean, how you are protected, and how to find a trial that might suit you. (6 min read)

Living well

What Exercise Does for Your Body: and how much you really need (video, 4:38)

Living with breast cancer: body image, lymphedema and hormone therapy side effects: Practical help with body changes and intimacy, lowering your risk of lymphedema, managing hormone therapy side effects, fatigue, work and follow-up care after breast cancer. (5 min read)
Managing side effects of cancer treatment: Practical, friendly tips for common side effects of cancer treatment: tiredness, nausea, mouth sores, hair loss, numbness and tingling, skin changes, low blood counts and "chemo brain." Report them, don't just endure them. (7 min read)
Eating well during cancer treatment: Practical tips for eating well during cancer treatment: getting enough protein and energy, coping with poor appetite, nausea and taste changes, food safety, and what to know about supplements. (6 min read)
Your feelings matter: emotional health and support with cancer: Fear, sadness, anger and worry are common after a cancer diagnosis. Practical ways to cope, when to ask for help, crisis support (9-8-8), talking with family, and support for caregivers. (6 min read)
Work, money and practical matters: Practical help after a cancer diagnosis: telling your employer, time off and benefits, fertility preservation before treatment, getting to appointments, and keeping paperwork in order. (6 min read)

When to get help

Call 9-1-1 now

Trouble breathing or severe shortness of breath
Chest pain or pressure
Coughing up blood
Fainting, or new confusion or drowsiness that's hard to wake from
A seizure
Sudden weakness or numbness of the face, arm or leg, trouble speaking, or loss of vision (signs of a stroke)
Swelling of the face, lips or throat, hives or wheezing during or after a treatment (a severe allergic reaction)
A swollen, painful leg together with sudden shortness of breath or chest pain
Fever with feeling very unwell, confusion, fainting or trouble breathing while on chemotherapy

Call 9-1-1 or your local emergency number. Don't drive yourself.

Call your cancer centre now

A temperature of 38 °C (100.4 °F) or higher, or shaking chills, during chemotherapy: call your cancer centre's 24-hour line right away. If you can't reach them, go to the nearest emergency department.
Redness, warmth, pus, a bad smell or opening at your surgery wound, a swelling that keeps filling with fluid (seroma), or a problem with your drain
Swelling, heaviness or tightness in your arm, hand, breast or chest on the treated side (possible lymphedema), or an arm that is red, hot and sore (possible infection)
Skin in the radiation area that blisters, peels, weeps or is very painful
Mouth sores that stop you eating or drinking, or diarrhea or vomiting that doesn't settle within a day
Numbness, tingling or pain in your hands or feet that is getting worse
One leg that is swollen, red, warm or painful (a possible blood clot, especially if you take tamoxifen)
Vaginal bleeding or spotting that is unusual for you, especially if you take tamoxifen
New shortness of breath, a cough that won't go away, or swollen ankles while on HER2-targeted therapy
On immunotherapy: new diarrhea, stomach pain, rash, cough, yellow skin or eyes, extreme tiredness or bad headaches
Low mood or worry that lasts more than two weeks

Use the 24-hour line. Don't wait for your next appointment. If you can't reach anyone and you're worried, go to emergency.

If you have any of the emergency signs, call 9-1-1 or your local emergency number right away. Don't drive yourself to the hospital. During chemotherapy, a fever can be a sign of a serious infection, even if you feel only a little unwell. Keep your cancer centre's 24-hour number in your phone and on your fridge, and bring your treatment card or medicine list if you go to emergency. If you're not sure whether something matters, call.

Fever and when to get help during cancer treatment: Clear lists to help you decide: a fever of 38.0 °C (100.4 °F) during chemotherapy is an emergency. Plus when to call 9-1-1, when to call your cancer centre's 24-hour line, and immunotherapy side effects to report. (6 min read)

Questions to ask your team

A printable list of questions to bring to your next appointment.

Go deeper

Written for clinicians and students. More technical material from Hibbert Medical, for readers who want more detail.

Podcast summaries

Cancer podcasts, summarized: Cancer podcasts with written summaries, including breast cancer research.
Women's health podcasts: Clinicians and researchers on women's health.
Mental health podcasts: Stress, mood and coping with a serious illness.

Lectures

Breast Carcinoma: Typing, Grading, and Biomarkers: What the pathology report means: ER, PR, HER2 and grade.
Surgical Management of Invasive Breast Cancer: Lumpectomy, mastectomy and how the choice is made.
Axillary Management in Breast Cancer: Checking and treating the lymph nodes under the arm.
Whole Breast Irradiation After Breast-Conserving Surgery: Radiation after lumpectomy.
Hereditary Breast and Ovarian Cancer: BRCA1/2 and Beyond: Inherited risk, genetic testing and what it means for families.
Autologous Breast Reconstruction: DIEP Flap: Rebuilding the breast with your own tissue.
Cardio-Oncology: Protecting the heart during cancer treatment.

Seminars

Breast Disease: Clerkship seminar: breast lumps, breast cancer and treatment.

Clinical cases

Invasive Ductal Carcinoma: The most common breast cancer, from biopsy to treatment plan.
Targeted Therapy in HER2-Positive Breast Cancer: How HER2-targeted medicines work.
Adjuvant Radiation for Breast Cancer: Radiation after surgery, and what to expect.
Lymphedema Secondary to Breast Cancer Treatment: Arm swelling after treatment, and why it happens.

Oncology regimen tutorials

Dose-dense AC → paclitaxel: Anthracycline then taxane chemotherapy for early breast cancer, with G-CSF support.
TCHP: Docetaxel, carboplatin and dual HER2 blockade for HER2-positive early breast cancer.
Monoclonal antibodies and biologics in oncology: Special tutorial: mechanisms, antibody–drug conjugates, bispecifics and class toxicities.
Immune checkpoint inhibitors and irAEs: Special tutorial: how PD-1, PD-L1 and CTLA-4 blockade works, and managing immune-related side effects.

Common questions

What kind of breast cancer do I have?

Breast cancers are sorted by where they start and by what fuels their growth. Your pathology report will say whether the cancer is non-invasive (DCIS) or invasive, and will list its grade. It will also say whether the cancer has hormone receptors (ER and PR) and how much HER2 protein it has. These results tell your team which treatments are most likely to work for you.

Will I need a mastectomy?

Not always. Many people can choose breast-conserving surgery (lumpectomy) followed by radiation. For many early cancers, this works as well as a mastectomy. The right choice depends on the size and place of the tumour, your breast size, your genes and what matters to you. Ask your surgeon to walk you through both options, and about reconstruction if you have a mastectomy.

Why do I need so many tests before treatment starts?

Each test fills in part of the picture: how big the cancer is, whether it has reached the lymph nodes or elsewhere, and what drives its growth. Waiting for results can feel hard. But taking a few weeks to plan carefully is usually safe, and it helps your team choose the best treatment for you.

Can men get breast cancer?

Yes. Men have a small amount of breast tissue, and breast cancer can start there. It is much less common than in women. It is diagnosed and treated in much the same way, and most of the information on this page applies to men too. Men with breast cancer are often offered genetic testing.

Is it normal to feel this scared?

Yes. Fear, anger, sadness and numbness are all very common after a breast cancer diagnosis. These feelings often ease once you have a plan. You don't have to cope alone: your team can connect you with social workers, counsellors and support groups. If you are thinking about suicide, call or text 9-8-8 in Canada or the U.S., or call 9-1-1.

Sources for this page

Back to Cancer: types of treatment, side effects and support for any cancer

General information, not medical advice. It does not replace your own care team. If you think you or someone else is having a medical emergency, call 9-1-1 or your local emergency number. If you are in crisis or thinking about suicide, call or text 9-8-8 (Canada and the US).

All After a Diagnosis guides