# Extracellular Vesicles and Artificial Intelligence: Unique Weapons against Breast Cancer
### Breast Cancer Classification  
BC can be classified using morphological/histological features based on the cells giving rise to the tumor; lobule cells (lobular carcinoma) or milk ducts (ductal carcinoma) are the most frequent. Their ability to invade other tissues to metastasize classifies them as \"non-invasive\" or \"invasive\". The in situ (noninvasive) forms of ductal and lobular carcinomas are abbreviated as DCIS (ductal carcinoma in situ) and LCIS (lobular carcinoma in situ), respectively. Ductal and lobular carcinomas can also reach the metastatic stage, such as tubular, papillary, mucinous, or chriiform carcinomas (less common forms). Using the TNM classification, the parameter \"T\" evaluates the size of the tumor on a scale of 1 to 4 (T1-T4), \"N\" refers to the involvement of lymph nodes adjacent to the tumor, and \"M\" indicates the presence of metastases. Moreover, the molecular characterization of invasive breast cancer involves the presence and dosage of specific hormonal cellular receptors (HRs), such as estrogen-positive (ER+), progesterone-positive (PR+), and human epidermal growth factor receptor2-positive (HER2+) receptors, and a triple-negative tumor is characterized by the absence of all the abovementioned receptors. HR overexpression induces a high replicative power in the tumor, with consequent aggressiveness, and is therefore useful for predicting its growth over time. Hormone-responsive tumors represent approximately 70%, HER2-positive tumors represent about 20%, and triple-negative breast cancer cases comprise 15% [11]. BC classifications and their relative prevalence percentages and invasiveness/colonization processes are reported in Figure 1.  
The evaluation of biological parameters, the cancer prognosis, the psycho-physical condition of the patient, and previous treatments received in a neoadjuvant/adjuvant context affect the choice of systemic treatment by a clinician. BC patients' treatment is based on a surgical approach, preceded/followed by neoadjuvant/adjuvant treatment such as hormone therapy and targeted chemotherapy drugs, according to the type of tumor. Immunotherapies try to stimulate the lost immune system activity using vaccines, immune checkpoint inhibitors [11], and the modification of immune cells and microbiota, as occurs in endometrial diseases [12]. With awareness in the media of the topic and the regional distribution of screening campaigns as a preventive approach, accompanied by diagnostic-therapeutic implementation and the availability of new anticancer drugs, the overall survival of critical metastatic patients has significantly increased. There are many steps forward for the characterization and identification of BC and a therapeutic approach to its treatment, but there are still many points that need to be clarified. A classical approach investigated the alterations in canonical molecular pathways and the identification of new biomarkers such as miRNA involved in cancer progression, metastasis, and drug chemoresistance [13]. The identification of new pathways through the characterization of alternative forms of cell-cell communication that play a role in carcinogenesis and tumor aggressiveness is needed. In the context of microparticles, the involvement of extracellular vesicles (EVs) in many different types of tumors has already been investigated. The next section briefly introduces and describes EVs, the underlying reasons for their importance, and the success achieved in recent years.