Invasive lobular carcinoma of the breast: response to hormonal therapy and outcomes

Eur J Cancer. 2008 Jan;44(1):73-83. doi: 10.1016/j.ejca.2007.10.009. Epub 2007 Nov 26.


Invasive lobular carcinoma (ILC) comprises approximately 5-15% of breast cancers and appears to have a distinct biology. It is less common than invasive ductal carcinoma (IDC) and few large studies have addressed its biologic characteristics and behaviour with respect to long-term clinical outcome and response to adjuvant therapy.

Methods: This study is based on a large and well-characterised consecutive series of invasive breast carcinomas with a long-term follow-up (up to 25 years). This series included 415 (8%) patients with pure ILC and 2901 (55.7%) with IDC (not otherwise specified) identified from a consecutive cohort of 5680 breast tumours presented to our Breast Unit that were treated in a similar conventional manner. Clinicopathological, therapy and outcome information as well as data on a large panel of biomarkers were available.

Results: Compared to IDC, patients with ILC tended to be older and present with tumours which are more frequently lower grade (typically, grade 2 [84%]), hormone-receptor positive (86% compared to 61% in IDC), of larger size, and with the absence of vascular invasion. A higher frequency of ILC was placed in the good Nottingham Prognostic Index group (40% compared to 21% in IDC). ILC showed indolent but progressive behavioural characteristics with nearly linear survival curves which crossed those of IDC after approximately 10years of follow-up, thus eventually exhibiting a worse long-term outcome. Importantly, ILC showed a better response to adjuvant hormonal therapy (HT) with improvement in survival in patients who received HT compared with matched patients with IDC.

Conclusion: ILC is a distinct entity of breast cancer that responds well to adjuvant HT. These data add important clinical information for assessing the long-term benefits of adjuvant HT use in ILC.

MeSH terms

  • Adult
  • Aged
  • Antineoplastic Agents, Hormonal / therapeutic use*
  • Biomarkers, Tumor / metabolism
  • Breast Neoplasms / drug therapy
  • Breast Neoplasms / mortality
  • Breast Neoplasms / pathology*
  • Carcinoma, Ductal, Breast / drug therapy
  • Carcinoma, Ductal, Breast / mortality
  • Carcinoma, Ductal, Breast / pathology*
  • Carcinoma, Lobular / drug therapy
  • Carcinoma, Lobular / mortality
  • Carcinoma, Lobular / pathology*
  • Chemotherapy, Adjuvant
  • Cohort Studies
  • Female
  • Follow-Up Studies
  • Humans
  • Middle Aged
  • Neoplasm Metastasis / drug therapy
  • Neoplasm Metastasis / pathology
  • Neoplasm Staging
  • Prognosis
  • Survival Analysis
  • Treatment Outcome


  • Antineoplastic Agents, Hormonal
  • Biomarkers, Tumor