Breast Cancer PDF

Breast cancer Symptoms: nipple discharge and lump. Triple assessment: clinical features, imaging results (mammography and US) and pathological examination (histology, IHC) Routine tests: ER, PR (response to hormonal therapy), Her2 (Trastuzumab-based therapy). Immunohistochemistry: ER, PR, H...

Breast cancer Symptoms: nipple discharge and lump. Triple assessment: clinical features, imaging results (mammography and US) and pathological examination (histology, IHC) Routine tests: ER, PR (response to hormonal therapy), Her2 (Trastuzumab-based therapy). Immunohistochemistry: ER, PR, HER2, Ki67, other In situ hybridisation: FISH, CISH, DDISH: HER2 More recently: PCR, NGS. WGS Ductal carcinoma in-situ (DCIS) 20% - 25% of screen detected cases. the stage before cancer invade (matter of time). The low nuclear grade breast neoplasia family Includes precursor and invasive lesions similar immunophenotypic and molecular features: loss of long arm of chr 16 and gain of 1q similar nuclear features and low proliferation rate Different risk factors, better response to therapy, indolent course compared with high- risk lesions low nuclear grade breast noplasia grade 1 ductal tubular lobular mucinous NST carcinoma carcinoma carcnimoma  Secretory carcinoma pathognomonic ETV6-NTRK3 gene fusion. Small molecule inhibitors (larotrectinib and entrectinib) that target NTRK3 and other NTRK family members Need of ETV6-NTRK3 tests Tall Cell Carcinoma with Reversed Polarity (TCCRP) TCCRP frequently harbours IDH2 p. Arg172 mutations an invasive breast carcinoma with the neoplastic cell nests arranged in a predominantly solid papillary pattern, composed of columnar epithelial cells showing reversed polarity of the nuclei; absence of myoepithelial cells around the tumour nests. Expression of both low- and high-molecular-weight cytokeratin’s; a triple-negative or weakly hormone receptor–positive phenotype. Seen in 84% of cases. Not often found in other types of invasive breast cancer. IHC subtypes Luminal A Luminal B Her2 Triple negative Her2 low ER, PR + ER, PR +/- ER, PR - ER, PR - ER, PR - Her2 - Her2 +/- Her2 +3 score Her2 - Her2 +1/+2 Ki67 low Ki67 higher +2 FISH FISH - subdivded by basal 40-50% of BC cytokeratin hetrogenous expression ck5 poplution and EGFR include BRCA associated tumours BCL2 is a marker of good prognosis across all subtypes  Therapy Neoadjuvant therapy immunotherapy Her2 low used in early BC Indicated for PD-L1 considered negative. positive metastatic TNBC not suitable for anti-HER targeted therapy Pembrolizumab Enhertu Atezolizomab