Clinical Characteristics and Survival Outcomes of Infiltrating Lobular Carcinoma: A Retrospective Study of 365 Cases in China

Abstract

The objective of this study was to compare the demographic characteristics, clinicopathological factors and survival outcomes between infiltrating lobular carcinoma (ILC) and infiltrating ductal carcinoma (IDC) using our single-center database. Methods: Seventeen thousand two hundred and three breast cancer patients were treated at Fudan University Shanghai Cancer Center (FUSCC) from January 2000 to December 2017. We identified 365 cases with ILC and 16,838 cases with IDC. The Pearson chi-square test was used to compare tumor characteristics, and the Kaplan-Meier methods were used to perform the survival analysis. Results: ILC had some distinctive characteristics from IDC such as older age (ranged from 61 to 80: ILC 26.8% vs IDC 19.9%, P < 0.001; over 80: ILC 1.6% vs IDC 0.8%, P < 0.001), larger tumor size (ranged from 2 to 5: ILC 45.2% vs IDC 37.1%, P = 0.011), much more hormone receptor expression (ILC 92.9% vs IDC 73.0%, P < 0.001), extremely less HER-2 expression (ILC 7.1% vs IDC 25.9%, P < 0.001). The overall survival and disease-free survival of ILC were worse than IDC (5-year OS, ILC 93.6% vs IDC 94.5%, P < 0.001; 5-year DFS, ILC 88.5% vs IDC 91.6%, P = 0.008). It was worth noting that the ILC patients had a worse overall survival than IDC patients after our propensity score matching study (P = 0.037). The univariate analysis concluded that positive HR (hormone receptor), high expression of Ki-67 and higher pathologic tumor stage were poor prognostic markers of ILC. Multivariate analysis demonstrated that tumor stage was a poor prognostic marker after adjustment for the effects of the above three factors. The most common primary site of metastasis was bone, but the proportion in the ILC group was much higher than that in the IDC group (56.25% vs 36.40%, P = 0.003). Conclusion: Compared with IDC, ILC survived worse and was more prone to bone metastasis. Therefore, a comprehensive understanding of ILC and specific treatments are needed for further research.

Histologic heterogeneity predicts patient prognosis of HER2‐positive metastatic breast cancer: A retrospective study based on SEER database

“…Specifically, the patients with IDC‐ILC tended to have more bone metastasis and less lung metastasis, which has been reported in TNBC 18 . For ILC and IDC‐oth subtypes, the patients showed a higher proportion of bone metastasis and a decreased proportion of lung, liver, and brain metastasis, in accordance with published researches 18,33 . The above results showed that the distribution of histological subtypes was discrepant in four metastatic sites, suggesting that histological subtypes may have preferential distant metastasis sites (DMS), and thus lead to different prognoses of HER2+ MBC patients.…”

“…18 For ILC and IDC-oth subtypes, the patients showed a higher proportion of bone metastasis and a decreased proportion of lung, liver, and brain metastasis, in accordance with published researches. 18,33 The above results showed that the distribution of histological subtypes was discrepant in four metastatic sites, suggesting that histological subtypes may have preferential distant metastasis sites (DMS), and thus lead to different prognoses of HER2+ MBC patients. Combined with the fact that patients with different metastatic sites have different outcomes, we speculated whether the prognosis of HER2+ MBC patients can be predicted based on the specific histological subtypes and specific metastatic sites.…”

Case report: Cutaneous metastases as a first manifestation from breast cancer with concurrent gastric metastases

“…ILC was prone to luminal A subtype, CDH1 mutations and deletion of E-cadherin mRNA expression ( Han et al, 2022 ). The E-cadherin gene function prevents tumor invasion, and in ILC the deletion of E-cadherin results in an increased capacity for tissue invasion ( Vleminckx et al, 1991 ).…”

Classifying invasive lobular carcinoma as special type breast cancer may be reducing its treatment success: A comparison of survival among invasive lobular carcinoma, invasive ductal carcinoma, and no-lobular special type breast cancer

“…Studies in which the pathological complete response to neoadjuvant chemotherapy is rare and positive surgical margin rate is higher in ILC [ 13 , 22 , 26 ]. This uncertainty may have made mastectomy a more common treatment option for ILC than IDC [ 6 , 7 , 14 ]. In another retrospective series, with only larger tumor size as a poor prognostic factor, ILC had lower survival compared to IDC [ 6 ].…”