**6. Clinical breast cancer diagnosis techniques**

The assessment methods and popular imaging techniques that will aid physicians in providing better care to patients and advancing clinical diagnosis are discussed below.

1.History and physical examination of breast cancer

The clinical history of breast cancer patients is used to assess the risk of developing cancer and to show the existence or absence of breast disease symptoms [21]. Age at menarche, menopausal status, prior pregnancies, and usage of hormone replacement therapy or oral contraceptives beyond menopause are all factors to consider. Personal as well as family history should be carefully investigated. Breast soreness, weight loss, bone pain, tiredness, and nipple discharge are just a few of the symptoms to check into. During a physical examination, doctors look at the breasts, the area around the neck and collarbone, and the armpits (axillae). Any anomalies in the breasts, such as lumps or other breast cancer signs, are investigated. Lymph nodes, which are often enlarged in breast cancer patients, are also assessed [22, 23].

2.Self examination

The value of breast self-examination is debatable since no benefit in terms of decreased mortality has been demonstrated. Most doctors teach women to do monthly self-examinations in order to get familiar with their normal structure and to give them authority over their own healthcare. Self-examination may reveal irregularities in breast size and form. Sreedharan et al. performed research at hospitals in the United Arab Emirates. A self-administered structured questionnaire was utilised to look at self-examination and knowledge practises. This research [24] produced satisfactory outcomes. These studies have

**Figure 4.** *Stages in development of breast cancer.*

demonstrated that a continuous breast cancer education programme may help people become more aware of the disease. Ceber et al. performed research on Turkish women's breast self-examination and health attitudes, concluding that early detection of breast cancer may avoid physical diseases and early mortality. He further claimed that just one out of every seven patients with breast cancer receives a timely diagnosis [25].

3.Mammography

Mammography (MG) is the recommended method for screening and detecting breast cancer, and it aids physicians in gathering clinic data on BC patients. The data indicates that early MG screening may decrease the death rate of BC patients by 30 percent to 40 percent [26]. Meanwhile, only 4 percent −10 percent of BC patients have MG as a positive diagnostic finding. With the passage of time, MG continues to grow. The two primary methods for diagnosing BC patients in clinic are contrast-enhanced mammography (CEM) and digital breast tomosynthesis (DBT) [27, 28]. Age, ethnicity, personal history, radiologist expertise, and technique quality all influence mammography sensitivity. In high-density breasts in premenopausal women, sensitivity may be decreased. Mammography has a number of disadvantages, including the use of ionising radiation, inability to diagnose thick breasts, high false-positive and false-negative rates, and an unpleasant examination.

4.Ultrasonography

Breast ultrasonography is a low-cost and commonly available screening method that detects malignancies by rebounding acoustic waves off breast tissue. To identify the anatomy of the human breast, an ultrasonic transducer is utilised to detect the acoustic waves reflected off it. Although less efficient than mammography, breast ultrasonography increases cancer detection rates in high-risk women and helps in the identification of cysts and solid masses. For women at high risk of breast cancer, pregnant women, and those who are unable to undergo mammography, breast ultrasonography has been recommended as a supplement to mammography. When breast ultrasonography and mammography are used together, the sensitivity of the imaging increases at the cost of specificity and biopsy rates. Because the reverberant characteristics of healthy and malignant tissues are so similar, breast ultrasonography fails to identify many tumours. It also necessitates the employment of qualified radiologists, which has a big impact on sensitivity and specificity [29].

5.Magnetic resonance imaging

MRI creates pictures at different cross-sections by mixing a strong magnetic field with RF signals. Breast MRI is suggested for high-risk women, but not for the general population because of its high rate of inaccuracy, higher expense, time commitment, insufficient number of units, requirement for trained radiologists, and lack of therapeutic effect. The American Cancer Society (ACS) has published recommendations for utilising MRI as a complement to mammography, and for specific demographic groups, such as BRCA mutation carriers and those at higher risk of complications, annual MRI scans are advised. In women at high risk of breast cancer, MRI is less specific but more sensitive than mammography and ultrasound in identifying small lesions [30].

6.Nuclear medicine

It is a kind of molecular imaging in which a person is administered a radioactive substance, and the radiation released by the radiopharmaceutical is shown by sensitive emission detectors such as gamma cameras and PET detectors located outside the patient's body. The combination of a CT scanner and a gamma camera, as well as a CT scanner and a PET scanner, is a significant advance in the identification and localization of disease.

7.Single photon emission computerised tomography (SPECT)

This method employs single photon radionuclides that produce gamma rays, such as gallium-67, iodine-131, and technicium-99. It's a fast and precise scan for the organ of concern. It may be used over the whole body, is quite safe in terms of radiation dose, and is effective in detecting both primary and metastatic tumours. The abbreviation PET/CT refers to positron emission tomography. PET/CT is also low-radiation since it utilises positron-emitting radionuclides including oxygen-15, fluoride-18, and carbon-11 to produce positrons. In positron emission tomography, a radioactive version of glucose, such as [18F] fuoro-2-deoxy-d-glucose, is a typical tracer. Tissues with greater metabolic needs, such as developing cancer cells, absorb the tracer more readily, which is seen on the scan. Using a combination of CT and PET, significant information about a range of situations impacting the different organs of the body may be readily mapped. PET/CT is extremely sensitive and accurate for predicting opaque and distinct areas of loco-regional lymph nodal extent and/or far-away metastases that are not apparent on conventional imaging, with up to 25% of patients having their staging changed. This technique is used to plan management by describing the primary disease's spread. It's also utilised in re-staging and treatment follow-up after a return of a managed disease [31].
