Comparison of survival in non-metastatic inflammatory and other T4 breast cancers: a SEER population-based analysis

Abstract

Background Previous studies have reported poor survival rates in inflammatory breast cancer (IBC) patients than non-inflammatory local advanced breast cancer (non-IBC) patients. However, until now, the survival rate of IBC and other T4 non-IBC (T4-non-IBC) patients remains unexplored. Methods Surveillance, Epidemiology, and End Results (SEER) database was searched to identify cases with confirmed non-metastatic IBC and T4-non-IBC who had received surgery, chemotherapy, and radiotherapy between 2010 and 2015. IBC was defined as per the American Joint Committee on Cancer (AJCC) 7th edition. Breast Cancer-Specific Survival (BCSS) was estimated by plotting the Kaplan-Meier curve and compared across groups by using the log-rank test. Cox model was constructed to determine the association between IBC and BCSS after adjusting for age, race, stage of disease, tumor grade and surgery type. Results Out of a total of 1986 patients, 37.1% had IBC and mean age was 56.6 ± 12.4. After a median follow-up time of 28 months, 3-year BCSS rate for IBC and T4-non-IBC patients was 81.4 and 81.9%, respectively (log-rank p = 0.398). The 3-year BCSS rate in HR−/HER2+ cohort was higher for IBC patients than T4-non-IBC patients (89.5% vs. 80.8%; log-rank p = 0.028), and in HR−/HER2- cohort it was significantly lower for IBC patients than T4-non-IBC patients (57.4% vs. 67.5%; log-rank p = 0.010). However, it was identical between IBC and T4-non-IBC patients in both HR+/HER2- (85.0% vs. 85.3%; log-rank p = 0.567) and HR+/HER2+ (93.6% vs. 91.0%, log-rank p = 0.510) cohorts. After adjusting for potential confounding variables, we observed that IBC is a significant independent predictor for survival of HR−/HER2+ cohort (hazards ratio [HR] = 0.442; 95% CI: 0.216–0.902; P = 0.025) and HR−/HER2- cohort (HR = 1.738; 95% CI: 1.192–2.534; P = 0.004). Conclusions Patients with IBC and T4-non-IBC had a similar BCSS in the era of modern systemic treatment. In IBC patients, the HR−/HER2+ subtype is associated with a better outcome, and HR−/HER2- subtype is associated with poorer outcomes as compared to the T4-non-IBC patients.

Comparison of the genomic alterations present in tumor samples from patients with metastatic inflammatory versus non-inflammatory breast cancer reveals AURKA as a potential treatment target

“…With regard to the distribution of the molecular subtypes, 75% of the IBC tumors are classified in the more aggressive basal-like, HER2-positive and luminal B subtypes, as opposed to only 54% for non-IBC [ 3 ]. Patients with IBC generally have a worse survival than patients with non-IBC [ 2 ], potentially restricted to the triple-negative subtype [ 4 ]. Despite improvement of treatment regimens for breast cancer in time, patients with IBC are often excluded from trials investigating targeted therapies, and specific therapies for IBC are lacking.…”

Treatment Response, Tumor Infiltrating Lymphocytes and Clinical Outcomes in Inflammatory Breast Cancer–Treated with Neoadjuvant Systemic Therapy

“…The median age of diagnosis is generally lower for IBC in comparison with locally advanced non-IBC (57.3 years for IBC vs. 64.3 years for locally advanced non-IBC; refs. 13, 14 ).…”

ER+/PR− phenotype exhibits more aggressive biological features and worse outcome compared with ER+/PR+ phenotype in HER2-negative inflammatory breast cancer

“…IBC is more likely to be estrogen receptor-negative and HER2-positive compared with non-IBC 8 , 9 . Besides, some researches have demonstrated that patients with IBC exhibited higher percentage of progesterone receptor-negative status compared with that of patients with non-IBC (55–56.7% versus 32–46.8%) 9 , 10 . While, it is still unknown whether the absence of PR expression will lead to worse prognosis of IBC or not.…”