Clinico-pathological characteristics and treatment outcome in invasive lobular carcinoma of the breast: An Indian experience

ABSTRACT

BACKGROUND: Invasive lobular carcinoma (ILC) is the second most common histologic subtype of breast cancer and accounts for 10%–15% of all breast cancers in the west. There is a scarcity of data on ILC from the Indian subcontinent. This report intends to present the patterns of care, survival outcomes, and prognostic factors of ILC treated in a tertiary care institute. MATERIALS AND METHODS: This retrospective analysis included consecutive patients diagnosed with ILC and registered at our Institute between 2009 and 2016. RESULTS: We included 97 patients with a median age of 53 years (range 28–80). American Joint Committee on Cancer (7th edition) stage distribution was stage I-8.24%, stage II-45.36%, stage III- 34.10%, and stage IV-12.30%. Bilateral breast cancer was seen in 8 cases. Estrogen receptor, progesterone receptor, and HER 2/neu positivity was 90%, 85%, and 9%, respectively. Triple-negative breast cancer constituted 5% of cases. Twenty-nine events were recorded (systemic and locoregional relapse) with a median follow-up of 3.5 years. Three years relapse-free survival (RFS) and overall survival were 80% and 60%, respectively. Bones were the most common site of metastasis. Age <45 years [HR-1.4 (0.8–2.1), P < 0.001] and advanced clinical tumor stage [T4, HR-2.1 (1.1–3.8), P = 0.001] were associated with poor RFS. CONCLUSION: ILC constituted 2.5% of breast cancer cases at our institute. Triple negativity and HER-2/neu positivity were seen in 9% and 5% of cases, respectively. Age <45 years and advanced clinical tumor stage were associated with poor RFS.