Stage 2 Breast Cancer

What is Stage 2 Breast Cancer?

Stage 2 breast cancer is early-stage cancer characterized by the involvement or spread of cancer in the breasts, axillary lymph nodes, or both.

In this stage, the tumor can be less than 5 cm in size in the axillary lymph nodes or larger than 2 cm in size in the breast.[¹]

What are the Subtypes of Stage 2 Breast Cancer?

Breast cancer has multiple subtypes, and the classification has evolved over the years. The most widely accepted classification type is based on the expression of different hormones, like progesterone (PR), estrogen (ER), and human epidermal growth factor (HER2). Classification is critical to ensure proper diagnosis and an effective course of action for treatment. According to this, there are 4 major subtypes of breast cancer, namely;[²]

Luminal A - 50% frequency, good prognosis
Luminal B - 15% frequency, middle prognosis
HER2-positive - 20% frequency, middle/bad prognosis
Triple-negative - 15% frequency, bad prognosis

Aside from these, another major subtype of stage 2 cancer includes ductal carcinoma in situ (DCIS). It is non-invasive cancer where the cancerous cells are found in the breast milk duct lining.[³] About 1 in 5 new breast cancers will be DCIS. However, it has a good prognosis, and nearly all women at this stage are cured.[⁴]

Stage 2 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 cancer has spread from its origin

Stage 2 breast cancer is further classified into stages IIA and IIB, depending on the breast tumor size, location, grade, and biomarker:

How Common is Stage 2 Breast Cancer?

Female breast cancer is highly prevalent and represents 15% of all new cancer cases in the U.S. The estimated number of cases in 2022 was around 287,850, higher than any other cancer type.[⁷] It is the second leading cause of death among women overall and the leading cause of cancer death among Hispanic women.[⁸]

It can occur in both females and males. In females, around 264,000 cases are diagnosed yearly in the U.S. In males, about 2,400 cases are diagnosed each year.[⁸]

How is Stage 2 Breast Cancer Diagnosed?

Many individuals with breast cancer do not show symptoms until the cancer has spread; thus, routine screening is required in females for early detection. There are multiple methods of diagnosis, and doctors recommend one according to the patient’s general health, age, previous medical tests, and the type of cancer suspected.

The series of diagnostic tests begin when a patient or doctor notices a swollen lump or an abnormal mass on a screening mammogram or during self-examination.[⁵] The following are the types of diagnostic tests available for second-stage breast cancer:[⁵],[⁹],[¹⁰],[¹¹]

Imaging Tests

Mammogram - usually recommended when something suspicious is suspected in a screening mammogram. It has high false-positive and false-negative rates and is usually recommended for women over 40.
Ultrasound - uses acoustic waves for diagnosis. It is used to differentiate between a solid mass and a fluid-filled cyst.
Breast MRI - uses strong magnetic fields with RF signals for better resolution. It is used in women with a high cancer risk or to analyze how far cancer has spread.
Computed tomography (CT) scans - a quick nuclear exam determining metastasis in a single exam.
Positron emission tomography (PET) scans - examines glucose consumption as cancerous cells consume more glucose than normal cells. It resembles a nuclear scan and forms functional imaging of biological processes.

Biomarkers

Biomarkers can also be used for early breast cancer stage 2 detection. There are two types of biomarkers:[¹⁰]

DNA Biomarkers - poor early detection due to low concentration but provide information on the tumor growth process.

Breast cancer 1 (BRCA1)
Breast cancer 2 (BRCA2)
p53
miRNAs

Protein Biomarkers - classified into predictive or prognostic and act as major indicators for breast cancer. Predictive protein markers provide information about potential therapeutic interventions. On the other hand, prognostic protein markers provide information about the patients.

RS/DJ-1
Heat shock protein 60 (HSP60), HSP90
Mucin 1 (MUC1)
HER2
Carbohydrate antigen 15-3 (CA15-3)

Biopsy

Biopsy is the only definitive diagnostic test and involves the removal of a small amount of tissue for microscopic examination. A biopsy is conducted after imaging tests, and biomarkers indicate that the patient may have cancer. Different types of biopsies are available, varying on the tissue sample and fluid taken and the needle size, such as core needle, fine needle, surgical, and image-guided.[⁵]

Stage 2 Breast Cancer Symptoms

Patients with stage 2 breast cancer may not experience any symptoms until the cancer has progressed too far. However, the following are some plausible symptoms associated with stage 2 breast cancer:[⁵],[¹²]

Nipple discharge occurring in only one or both breasts.
Pain in the breasts.
An abnormal mass or lump in the breast or armpit.
Swollen and reddened breasts.
Skin irritation or dimpled skin on the breast.
Changes in the shape and size of the breast.
Changes in the shape of the nipple, such as turning inward or getting flattened.

Stage 2 Breast Cancer Treatment

The treatment for stage 2 breast cancer has evolved significantly over the last few years. The focus has shifted towards improving survival rates, achieving local control, and preventing locoregional recurrence. The primary treatment option is surgery, considering the patient’s overall health, age, and previous medical tests and if the tumor is removable. For patients who are not suitable for surgery, systemic therapies are beneficial. However, it is important to note that combining first-line and second-line (systemic therapy) is the recommended approach to increase survival chances. A multi-disciplinary team should be made available to develop an effective treatment plan for the patient based on their changing clinical status.

Stage 2 Breast Cancer Surgery and Radiation

The first-line treatment option for stage 2 breast cancer is surgery. Surgery is targeted toward destroying cancerous cells near or in the breast. There are two major surgical options for stage 2 breast cancer: mastectomy and breast-conserving therapy (BCT). Both these surgeries show similar long-term survival chances and are the current standard of carea for stage 2 breast cancer. Aside from this, lymph node surgery is also considered during the early stages.

Standard of care refers to the treatment that is most widely agreed upon in the medical community regarding its effectiveness and is thus usually the most-common treatment as well

Mastectomy - it involves the complete removal of the breast. There are multiple types of mastectomies, and doctors recommend one according to the patient’s overall health, tumor progression, and preference.

Simple total mastectomy - includes removal of the entire breast, including the nipple, areola (the colored ring around the nipple), and overlying skin. The muscle underneath the breast isn’t removed.[¹³]
Skin-sparing mastectomy - useful for immediate reconstruction of the breast, nipple, or areola. Removes breast tissue but leaves healthy breast skin intact. Not recommended if the tumor is close to the skin.[¹³]
Nipple-sparing mastectomy - in this procedure, the nipple, areola, and underlying skin are preserved, and all the breast tissue is removed.[¹³] It has gained significant importance due to the increased quality of life.[¹⁴]
Modified radical mastectomy - the breast tissue, areola, nipple, and axillary lymph nodes are removed. The chest wall muscles remain intact.[¹³]
Radical mastectomy - recommended when cancer has spread to the muscles under the breast. Involves the removal of breast tissue, nipple, areola, lymph nodes, and chest wall muscle.[¹³]
Prophylactic mastectomy - involves removal of all breast tissue before cancer is found. It is recommended when patients have a BRCA gene mutation or a strong family history of breast cancer.[¹³]

Breast-conserving therapy or lumpectomy - a lumpectomy involves the removal of cancer and a cancer-free margin of healthy tissue surrounding the affected area. However, patients have a higher chance of recurrence; thus, lumpectomy coupled with radiation therapy is recommended, also known as breast-conserving therapy.[¹],[⁵]

Axillary lymph node dissection - breast cancer treatment also involves the evaluation of axillary lymph nodes under the armpit to determine how far the cancer has progressed or if it has spread to the lymph nodes. Around 10 to 25 axillary lymph nodes are removed to determine the stage. A patient can experience adverse effects like pain, swelling, limited shoulder movement, etc.[¹]

Axillary lymph node biopsy - when doctors have no clinical evidence of lymph node involvement, an axillary lymph node biopsy is conducted. It is a newer and improved approach for detecting tumor progression. In this, the sentinel node that receives lymph drainage from the breast is removed. It results in fewer side effects as compared to dissection.[¹],[⁵]

Radiation - involves high-energy x-rays to destroy cancer cells. The treatment regimen can last 3 to 6 weeks for 5 days a week. It can be given before or after surgery and effectively reduces recurrence rates. Radiation therapy is available in multiple types, differentiated based on the device and the area affected, such as[⁵]

External-beam radiation therapy - the most common type, can last for several days and is used for whole or partial breast radiation therapy.
Partial breast irradiation - focused on the affected area, commonly given after lumpectomy and reduces the number of days radiation is required.
Intensity-modulated radiation therapy - an advanced method of giving external-beam radiation therapy. Reduces dosage and damage to nearby organs.

Other Types of Treatment for Stage 2 Breast Cancer

For patients who are not eligible candidates for surgery, pose a higher risk of recurrence after surgery, or whose cancer has progressed to an advanced stage, systemic therapies are considered. These therapies can be given alongside surgery (“adjuvant” therapy or treatment) or before surgery to increase the effectiveness of the surgery (“neoadjuvant”).

Second-line treatment involves chemotherapy, targeted therapy, or hormonal therapy before and/or after the surgery.

Chemotherapy - involves using drugs to kill cancer cells and prevent progression. The therapy regimen involves a set number of cycles over a set period. It can be given once weekly or every 2 to 3 weeks. Some of the common drugs include Docetaxel, Doxorubicin, Carboplatin, and Paclitaxel. They are given separately or in combination.[⁵]
Targeted therapy - it is different from conventional systemic therapies as it focuses only on the cancer cells and reduces harm to nearby cells and organs. It targets cancer’s specific genes, proteins, and other tumor factors. Some of the commonly approved targeted therapies include hormonal therapies and monoclonal antibodies.[¹]
Hormonal therapy - it is an effective treatment option for early-stage cancers that test positive for estrogen or progesterone receptors. It involves blocking the hormones, especially estrogen, to prevent cancer recurrence. However, it can lead to serious side effects like decreased bone density and increased risk of heart disease. Tamoxifen and anti-aromatase drugs are effective for stage 2 or early-stage breast cancer.[¹]

Can Stage 2 Breast Cancer be Cured?

The answer to “is stage 2 breast cancer among the treatable cancers?” is difficult. The prognosis depends on the patient’s overall health, medical history, gender, tumor location and progression. Generally, stage 2 breast cancer is often referred to as early-stage cancer and is curable. The prognosis is better if the cancer is detected early and treated when small and localized to a single area. Effective treatment options are available, but not all patients are ideal candidates for surgery and radiation and thus need systemic therapies.

Prognosis: Stage 2 Breast Cancer Survival Rate

The prognosis of stage 2 breast cancer depends on the individual’s overall health and tumor progression. It is also dependent on the type of treatments they have available. The prognosis for stage 2 breast cancer is typically much better than that for later stages. Doctors determine prognosis based on two separate metrics:

Survival - the rate of survival looks at the % of patients who survive after initial diagnosis or treatment.
Quality of life (QOL) - the ability of the patient to continue to live a healthy and enjoyable life, considering both the status of their health condition and the medical interventions.

Stage 2 Breast Cancer Survival Rate

What is the stage 2 cancer survival rate? In breast cancer stage 2, the cancer is localized in the breast or has spread to the lymph nodes; survival rates for both vary accordingly. In stage IIA, when the tumor size is less than 2 cm or between 2 to 5 cm and localized to the breast, the five-year survival rate is 98%, and for stage IIB, when the tumor has grown and spread to the lymph nodes, it’s 95.6%.[¹²] Remember that no two individuals are alike, and the prognosis can vary from person to person.

Stage 2 Breast Cancer Recurrence Rate

The recurrence rate of breast cancer depends on the stage and timing. For instance, there is a higher chance of local recurrence during the first 5 years after treatment. The recurrence rate also depends on the treatment type. In most cases, patients who have undergone mastectomy or lumpectomy with radiation therapy have a 10 to 15% chance of local recurrence in 10 years after treatment.[¹⁵] Metastatic recurrence is also a significant problem; around 20–30% of patients in the early stages of breast cancer still die of metastatic disease.[¹⁶]

Stage 2 Breast Cancer Growth Rate

According to a study conducted in 2018 estimated the doubling time of breast cancer cells in 265 people with invasive breast cancer to see if there were differences among breast cancer subtypes by looking at serial ultrasounds. The results concluded that growth rate varies depending on breast cancer subtypes and their estrogen receptors. For instance, during an average interval of 57 days, 36% of tumors did not change in size, while 64% grew. Estrogen receptor-positive and HER2-negative cancers had greater doubling times and smaller increases in volume as compared to triple-negative breast cancer.[¹⁷]

Lifestyle Changes for Preventing and Managing Breast Cancer

The following preventive measures greatly impact the patient’s quality of life, their chances of acquiring or recurring breast cancer, and limiting the progression of the tumor.[¹⁸]

Maintain a healthy weight
Eat a healthy diet of whole grains, vegetables, and beans.
Be more physically active.
Limit alcohol consumption.
Breastfeed if you are a nursing mother.
Avoid supplements and meet nutritional needs through diet.

Impact of Body Weight and Diet

The WCRF reviewed 226 studies, including 456,000 women with breast cancer. Among them, 36,000 died, including 21,000 who died from breast cancer. The results supported the evidence that a higher BMI, waist-hip ratio, and waist circumference can increase the risk of death after diagnosis. For instance, the death risk increases by 7% for every 5-point (kg/m2) increase in BMI.[¹⁹]

Thus, patients need to maintain a healthy diet and closely monitor their weight. By increasing your intake of fruits, vegetables, and vegetable oil, you can indulge in a diet rich in β-carotene and vitamin E and reduce breast cancer risk. Moreover, the consumption of soy products also reduces risk and recurrence.[²⁰]

Conclusion

Takeaway

Breast cancer is a global health burden and the second leading cause of death in women in the U.S. Early detection results in a better prognosis; thus, stage 2 breast cancer is mostly curable if proper local and systemic therapies are provided. For treatment, multidisciplinary teams involving radiologists, pathologists, and physicians specializing in surgery and medical oncology are required to create an effective treatment plan for patients.

For better outcomes, patients should be educated about the importance of maintaining a healthy body weight before and after surgery to prevent a recurrence. Moreover, certain lifestyle changes, such as physical activity, a Mediterranean diet, etc., are required for a better quality of life.