Invasive Lobular Breast Carcinoma: Pleomorphic Versus Classical Subtype, Associations and Prognosis

Clin Breast Cancer. 2018 Apr;18(2):114-120. doi: 10.1016/j.clbc.2017.06.006. Epub 2017 Jun 23.

Abstract

Background: Invasive pleomorphic lobular carcinoma (IPLC) has been associated with a worse prognosis compared with classic invasive lobular carcinoma (cILC); however, studies are small and conflicting. We seek to examine the prognosis of women with IPLC compared with cILC.

Methods: A retrospective review of women with breast cancer at a single institution from 2003 to 2012 identified 193 women with invasive lobular carcinoma (ILC). IPLC was defined as ILC with a pathological description of primarily pleomorphic features and Nottingham histological grade score of 7, 8, or 9 or overall grade of 3 or mixed classic/pleomorphic features and overall grade of 3. All others were designated cILCs. Clinicopathologic variables, progression-free survival (PFS), per STEEP criteria, and overall survival (OS), using all-cause mortality, were examined in both groups.

Results: Of the 193 women, 46 (24%) had IPLC and 147 (76%) had cILC. The IPLC group had significantly higher stage at diagnosis and more Hispanic women, but there were no differences in other clinicopathologic features or treatment. Median follow-up was 57 months (0.1-155 months). In univariate analysis, IPLC was associated with worse PFS (log-rank P = .09, Wilcoxon P = .01) but no significant differences in OS (log-rank P = .20, Wilcoxon P = .16). In multivariate models adjusting for stage, IPLC was not significantly associated with PFS (hazard ratio [HR] 1.43; 95% confidence interval [CI], 0.73-2.79; P = .30) or OS (HR 1.52; 95% CI, 0.58-4.01; P = .40).

Conclusions: IPLC was initially associated with worse PFS, but this was attenuated after adjustment for cancer stage, and there were no differences in OS.

Keywords: Histology; Risk factor; Staging; Survival; Tumor grade.

Publication types

  • Comparative Study
  • Research Support, N.I.H., Extramural

MeSH terms

  • Antineoplastic Agents / therapeutic use*
  • Breast / pathology
  • Breast Neoplasms / mortality
  • Breast Neoplasms / pathology*
  • Breast Neoplasms / therapy
  • Carcinoma, Lobular / mortality
  • Carcinoma, Lobular / pathology*
  • Carcinoma, Lobular / therapy
  • Chemotherapy, Adjuvant / methods
  • Female
  • Follow-Up Studies
  • Humans
  • Mastectomy
  • Middle Aged
  • Neoadjuvant Therapy / methods
  • Neoplasm Grading
  • Neoplasm Invasiveness / pathology
  • Neoplasm Staging
  • Prognosis
  • Progression-Free Survival
  • Proportional Hazards Models
  • Radiotherapy, Adjuvant
  • Retrospective Studies
  • Survival Analysis

Substances

  • Antineoplastic Agents