Klinikopatologi Kanker Payudara Tipe HER2 di RSUP H. Adam Malik

Abstract

Background: HER2-positive breast cancer represents 15-20% of cases worldwide, characterized by HER2 overexpression leading to aggressive proliferation via PI3K/AKT and MAPK pathways, poor prognosis, and high metastasis rates. In Indonesia, limited data exist on HER2 subtype clinicopathology, prompting analysis at RSUP H. Adam Malik to inform targeted therapy and prognosis assessment. Methods: Descriptive retrospective study reviewing medical records of 140 HER2-positive (IHC 3+ or IHC 2+/FISH+) primary breast cancer patients aged ≥18 years diagnosed March 2020-March 2025 at RSUP H. Adam Malik Medan. Data on demographics and clinicopathological features (tumor size T, nodes N, metastasis M, grade, histology, Ki-67, LVI, TILs) analyzed descriptively using frequencies and percentages via SPSS. Results: Patients averaged 48.5±10.2 years (most 41-50 years, 34.2%), all female, 95.7% married, 98.5% without family history. Dominant features: invasive ductal carcinoma (86.8%), T2 size (50%), grade 3 (56.6%), N+ (66.9%), M0 (60.8%), LVI+ (58.8%), Ki-67 >20% (55.9%), TILs mild (33.8%). Conclusion: HER2-positive breast cancer at RSUP H. Adam Malik shows aggressive profile with predominant middle-aged females, T2/grade 3 tumors, nodal involvement, and high proliferation, underscoring need for early detection and HER2-targeted therapies like trastuzumab.