Stage 1 Breast Cancer

What is Stage 1 Breast Cancer?

Stage 1 breast cancer, also known as early-stage breast cancer, is a small, invasive tumor that has not spread to nearby lymph nodes. It is also called stage IA breast cancer.

At this stage, the tumor is 20 mm or smaller, but there may be no diagnostic evidence of a tumor in the breast.[1]

What are the Subtypes of Stage 1 Breast Cancer?

Breast cancer is a heterogeneous disease that has multiple subtypes. These subtypes are categorized by the expression of certain hormone receptors, such as progesterone (PR), estrogen (ER), and human epidermal growth factor (HER2). Therefore, there are four primary subtypes of breast cancer:[1][2]

  • Triple-negative (20%)
  • HER2-positive (10 – 15%)
  • Luminal A
  • Luminal B

Triple-negative breast cancer (TNBC) is more common among women under 40 and African-American women. However, it does not have the hormone receptors seen in other subtypes, i.e., ER, PR, and HER2. This makes TNBC an extremely aggressive form of breast cancer with a high recurrence rate and the potential to spread fast. You can find more about TNBC here.[1][2]

Stage 1 Breast Cancer Staging and Diagnosis

Breast Cancer Staging

In general, the TNM system is used to describe and classify cancers, including breast cancer, where:

  • T (tumor) describes the size and location of the tumor
  • N (nodes) indicates whether or not it has spread to nearby lymph nodes
  • M (metastasis) describes if and how far the breast cancer has spread from its origin

Stage 1 breast cancer is further classified into stages 0, IA, and IB, depending on the breast tumor size, location, grade, and biomarker:

How Common is Stage 1 Breast Cancer?

Breast cancer is highly prevalent, with over 287,850 cases estimated in 2022.[5] It generally affects females, who make up over 90% of the patient population, but it is also seen in males, with an estimated 2,400 cases a year. Breast cancer is the second most common cancer type among women in the U.S., with a higher death rate in black women than in white women.[6]

How is Stage 1 Breast Cancer Diagnosed?

Doctors employ multiple diagnostic tests to confirm breast cancer, determine its stage, and verify whether it has spread to the surrounding tissue or lymph nodes.[1] The following are the common tests and techniques used to detect the stage of breast cancer:

Tumor Markers

Tumor marker blood tests detect the presence of abnormal amounts of particular molecules in blood and tissue samples. These abnormal levels are caused by the cancerous cells disrupting the normal cell growth mechanisms and leading to the overproduction of certain molecules.[3]

Imaging Tests

Diagnostic imaging tests for breast cancer include the following:

  • Ultrasound imaging uses sound waves to identify and differentiate solid cancerous masses from non-cancerous fluid-filled cysts.[1],[3]
  • A mammogram is used as a screening test for women who are not experiencing any symptoms and a diagnostic tool for patients who may have signs such as nipple discharge or a small, new lump.[1]. It is an x-ray of the breast tissue that can detect cancerous masses.
  • Magnetic resonance imaging (MRI) is used to screen or detect if the cancer cells have spread further in the breast and to surrounding tissue.[1],[3]
  • Computed tomography (CT) nuclear scans may be used to detect tumors for diagnostic purposes.[3]
  • Positron emission tomography (PET) scans examine glucose consumption, as cancerous cells consume more glucose than normal cells.[3]


A biopsy takes a sample of breast tissue or fluid via a needle. Several biopsy techniques are available, based on the needle size and tissue sample required, such as core needle biopsy and surgical biopsy.[1],[3]. Depending on a patient’s needs, a doctor will recommend the best tolerable technique and extract the sample. The biopsy is analyzed in a lab for abnormalities. If detected, the tumor is classified based on hormone receptors (ER, PR, HER2) and grade.[1]

Breast Cancer Stage 1 Symptoms

The symptoms of early-stage breast cancer, i.e., stage 1 breast cancer, are listed below.[1],[4]

  • Skin irritation that causes sensitivity and rashes
  • Nipple discharge, which can occur suddenly and may be bloody
  • Textural changes on the breast skin that causes dimpling
  • Redness or swelling of the breast
  • Physical changes in the nipple, such as inversion or flattening
  • A lump in the breast or armpit

Stage 1 Breast Cancer Treatment

Breast cancer treatment plans are highly individualized and are developed by a multidisciplinary team that includes medical oncologists, radiologists, pathologists, physicians, and surgeons. These options are tailored to each patient based on age, general health, tumor stage, and subtype.

Stage 1 Breast Cancer Removal Surgery

For stage 1 breast cancer, surgery is the first line of treatment. It completely removes the localized tumor and surrounding tissue and drastically decreases the chances of a patient relapsing.

Two major surgical options are available for early-stage invasive breast cancers; lumpectomy and mastectomy. However, the choice of surgery does not determine the need for additional treatment. That depends on the unique characteristics and stage of the tumor.[1]

Lumpectomy - also known as breast-conserving surgery or partial mastectomy- involves the surgical removal of the tumor and a small margin of cancer-free healthy cells to prevent a recurrence.

It is the preferred surgery option for stage 1 breast cancer, but most patients will require radiation treatment after surgery. Recovery time is quicker, and women can return to their routine activities within 2 weeks.[1],[7]

Possible side effects of a lumpectomy include temporary swelling of the breast, pain or tugging sensation in the breast, and change in breast shape.[7]

Mastectomy – the surgical removal of the breast recommended when cancer has spread to multiple areas. It is also advised when radiation therapy is unsuitable or as a preventative measure for those with early-stage TNBC. The different types of mastectomies are listed below. [8]. For many of these options, breast reconstruction is possible.

  • Complete mastectomy – The surgical removal of all breast tissue, including the nipples, the areolas (the colored ring around the nipple), and the underlying skin.
  • Modified radical mastectomy - The total removal of the breast tissue, including nearby lymph nodes in the armpits, if the cancer is suspected of spreading. In some cases, a part of the chest wall muscle is also removed.
  • Radical mastectomy - The complete removal of the breast tissue, underlying skin, underarm lymph nodes, and chest wall muscle. This procedure is advised when cancer has spread to the surrounding chest muscles.
  • Nipple-sparing mastectomy – Only the breast tissue and the ducts leading to the nipple and areola are removed. The skin of the nipple and areola are preserved.
  • Skin-sparing mastectomy – The breast tissue, nipple, and areola are removed, but the skin over the breast is preserved.

Axillary lymph node dissection – The removal of nearby lymph nodes and surrounding tissue under the arms. This is necessary if the cancer cells have spread or are suspected of spreading. Generally, patients with stage 1 breast cancer or a small tumor (less than 5 cm) with 2 or fewer sentinel lymph nodes don't need a full axillary lymph node dissection. [1] However, doctors will biopsy the region before determining the best course of action.

Other Types of Treatment for Stage 1 Breast Cancer

Other treatment options are available for patients who require further treatment after surgery or are unsuitable for surgery.[1]

These treatments can be performed before the surgery (neoadjuvant) to lessen the tumor size and increase the efficiency of the treatment or after the surgery (adjuvant) to prevent a recurrence. The following are some of the second-line treatments available for stage 1 breast cancer:

  • Radiation therapy uses high-energy x-rays or other particles to destroy cancer cells. Doctors choose from multiple radiation therapies based on a patient’s overall health profile and tumor subtype. The treatment regime can range from 5 days to 6 weeks and can be given before or after surgery.[1]
  • Chemotherapy uses potent drugs to destroy cancer cells. Popular drugs include Docetaxel, Doxorubicin, Carboplatin, and Paclitaxel. These can be given once a week or every few weeks. Additionally, drugs can be given individually or in combination based on tumor subtype.[1]
  • Immunotherapy uses drugs that activate and enhance the body’s immune system to destroy cancer cells.
  • Hormone therapy works best on ER and PR-positive cancer types. It involves blocking or lowering the level of hormones in the body to stop the spread of cancer cells and prevent a recurrence. It is usually given before surgery and lasts for 3 to 6 months.[1]

Can Stage 1 Breast Cancer be Cured?

The primary question cancer patients want an answer to is, “can stage 1 breast cancer be cured?” Unfortunately, there is no clear answer as it significantly depends on the patient’s health, tumor subtype, stage, and how far the tumor has spread. Furthermore, patients who are not ideal candidates for surgery or second-line treatment options risk faster progression to advanced stages. However, if detected early or the tumor is small, the prognosis is better.

Prognosis: Stage 1 Breast Cancer Survival Rate

Doctors determine prognosis by studying the relevant data collected over many years and divided into the following metrics:

  • Survival - it is the percentage of specific-cancer patients who have not died over a set period of time, such as 5 years, after diagnosis.
  • Quality of life - it is the individual’s ability to continue with their routine and lead a healthy, enjoyable life despite their condition and burden of treatments.

Generally, the prognosis for stage 1 breast cancer is promising following timely primary and second-line treatments. However, it is important to note that no two patients are alike. Even though these survival rates are based on clinical data from a large population group, the results can vary widely from person to person

Stage 1 Breast Cancer Survival Rate

The 5-year survival rate for patients diagnosed with stage 1 breast cancer is 99.1% following surgery and the required second-line treatments, i.e. chemotherapy or radiation therapy.[5] Whereas the overall 5-year survival rate for breast cancer is 90.6%. [9]

Moreover, the 10-year relative survival rate for women with non-metastatic invasive breast cancer is 85% in the U.S.[1]

Stage 1 Breast Cancer Recurrence Rate

The metastatic recurrence rate for breast cancer patients is around 20–30%. This is a significant problem that indicates that even after treatment, early-stage breast cancer patients are still at risk of relapsing. Research suggests that one reason for this is the possible spread of dormant cancerous cells to secondary sites pre-diagnosis. [10]

Furthermore, these dormant cells may be unaffected by proliferative agents and become suddenly activated long after adjunct treatment has stopped.

Stage 1 Breast Cancer Growth Rate

Breast cancer is one of the fastest-growing diseases, and waiting for surgery can increase the risk of cancer spreading.

In a study that measured tumor growth in 323 cases of unifocal invasive breast cancer in women, researchers found significant increases in tumor size and volume during wait time for surgery, approximately 8 – 78 days.

Ultrasound imaging showed mean tumor diameter and volume increased from 14.7 mm and 1.3 cm3 to 15.6 mm and 1.6 cm3, respectively. These findings supported the aggressive nature of breast cancer and its high growth rate and clinical upgrading.[11]

Lifestyle Changes for Preventing and Managing Breast Cancer

Breast cancer is difficult to completely prevent. However, research suggests that several lifestyle changes can reduce the risk of developing the disease, delay progression, and manage its symptoms, such as:

  • Engaging in moderate to high-intensity activity for 30 to 60 minutes per day.[1]
  • Avoiding hormone replacement therapy or oral contraceptives after menopause.[1]
  • Maintaining a healthy weight and diet.[1]
  • Not smoking [12]
  • Reducing alcohol consumption [12]

Weight Management and Diet

Several studies have shown a link between weight and breast cancer prognosis, such that overweight or obese women have a poorer prognosis at the time of diagnosis. Furthermore, women who gain weight during or after treatment have a higher chance of recurrence and death. Weight gain negatively influences prognosis because it leads to an increase in sex hormones, the circulation of insulin-like growth factors, metabolic syndrome, and proinflammatory cytokines production that abets cancerous growth.[12]

Doctors recommend those at risk manage their weight and eat a healthy diet. However, it is important to point out that there is a lack of information on the impact of weight loss and management diagnosis and surgery, but findings suggest it can help reduce recurrence rates.

Many studies also suggest consuming high-fat dairy products or saturated fats can increase the risk of breast cancer mortality. However, there is no concrete evidence as to which type is more beneficial than another. Still, general research consensus supports a balanced diet high in lean meats, fruits, vegetables, and whole grains to effectively reduce recurrence. [12]



Breast cancer is the second most common cancer in women in the United States. It is also a leading cause of cancer-related death worldwide, and why many clinical trials are underway researching and developing better treatments and therapies, specifically the efficacy and safety of target therapies that have shown to have increasingly favorable long-term effects. Additionally, clinical research has ramped up efforts to improve screening and early detection tests since early treatments significantly improve prognosis.

The long-term survival rates for stage 1 breast cancer are better than its other stages. Therefore, surgery with second-line treatments should be prompt. Breast cancer is highly aggressive, and any delay in treatment can lead to rapid tumor growth and spread, putting the patient’s life at risk.

Women must regularly screen their breast tissue for lumps, especially those with a family history of breast cancer. Additionally, they must consult their physicians if they experience any abnormal symptoms. Finally, it is essential that those at risk consume a balanced diet and follow a healthy lifestyle, which can effectively reduce developing breast cancer, improve prognosis, and reduce relapse.