Background: Breast carcinoma is the second most common cancer in the world and is the most common cancer among women. Research on protein expression is associated with prognosis and opportunities for providing therapeutic agents. Recent research examines ALK with various characteristics in breast cancer. Anaplastic Lymphoma Kinase (ALK) is a tyrosine kinase receptor that plays a role in the signal transduction pathway, including the ERK, JAK / STAT, and PI3K-PKB / Akt pathways, that will cause proliferation and survival of tumour cells.

Objective: To analized the immunohistochemical expressions of ALK association with histological grading and molecular subtypes in invasive breast carcinoma patients.

Material dan Methods: Formalin-fixed paraffin-embedded tissue blocks of 44 invasive breast carcinoma patients were immunohistochemically studied for ALK expressions. All clinicopathological characteristics were obtained through medical records and pathology archives.

Results: This study found that positive ALK expression in 40 cases (90.1%), while a negative ALK expression of 4 cases (9.1%). The mean age of patients with invasive breast carcinoma was 47.40 (± 10.57) years. Patients with positive ALK expression had an average age of 46.08 ± 10.64 years, and the highest tumor size was T3 (75%). All cases with negative ALK expression were invasive carcinoma NST. This study also found that there was no relationship of ALK expression with grading and molecular subtypes in invasive breast carcinoma.

Conclusions: These findings can be considered in using ALK as a determinant of prognosis and therapeutic agents. The use of other biological markers and validation by using larger samples and more even distribution is needed for the determination of a more precise prognosis in this study.

Keywords: invasive breast carcinoma, ALK, ALK inhibitor