Special types of breast carcinoma include tumors with morphologies that deviate from invasive carcinoma of no special type (NST). As a group, special types comprise up to 25% of all breast cancers, and encompass entities ranging from low to high-grade, and with different hormone receptor and HER2 status. While invasive breast carcinoma of no special type (NST) constitutes ∼70% of all breast malignancies, the remaining 30% include various and rare (special) subtypes, defined by distinct morphology, molecular expressions, and/or genetic features; consequently, clinical course and treatment options vary significantly. NST makes up around 80% of all invasive breast cancers. If a tumour is made of more than 90% of a classical morphology with particular defined histological features, then it can be categorised as a ‘special type’ breast cancer. Lobular Carcinoma is the commonest special type and makes up aound 10% of all invasive breast cancers. In addition, SPC in situ can also be accompanied by invasive disease, which can be in the form of invasive breast carcinoma of no special type or mucinous, tubular, lobular or mixed subtypes [69, 75]. Histologic Type (Note D) ___ No residual invasive carcinoma ___ Invasive carcinoma of no special type (invasive ductal carcinoma, not otherwise specified) ___ Micro-invasive carcinoma ___ Invasive lobular carcinoma ___ Invasive carcinoma with lobular features ___ Invasive carcinoma with ductal and lobular features (“mixed type carcinoma”) Specialty. Oncology, Dermatology, Breast surgery. Invasive carcinoma of no special type ( invasive carcinoma NST ), invasive breast carcinoma of no special type ( IBC-NST ), invasive ductal carcinoma ( IDC ), infiltrating ductal carcinoma ( IDC) or invasive ductal carcinoma, not otherwise specified ( NOS) is a disease. Invasion may also be associated with mucinous differentiation or present as carcinoma of no special type (NST) . Invasive lobular carcinoma (ILC) mimicking SPC has been described in the differential diagnosis to SPC and also EPC but the small number of reported cases allows only limited conclusions [ 72 ]. The majority of breast cancers are classified as invasive ductal carcinoma of no special type (IDC) (75–80%) or invasive lobular carcinonma, classical type (ILC) (10–15%). This review will focus on the rare breast cancer subtypes that make up the rest of breast cancer diagnoses organized by the prognosis of the rare tumor (Table 1). These Tumor budding grade is a very useful histological prognostic indicator for colorectal cancer patients. Recently, it has been also reported as a significant prognostic indicator in invasive breast carcinoma patients. Our group and others have previously reported that the presence of a fibrotic focus in the tumor is a very useful histological finding for accurately predicting the prognosis in A palpable nodule in a postmenopausal woman is statistically most likely to be an invasive carcinoma. Invasive ductal carcinoma, also known as “no special type,” is the most common type of breast cancer. The morphologic features are variable but generally show malignant ducts invading surrounding stroma. H9jvW.