Carson Craig McFeetors, Domhnall O’Connor, Gloria Avalos, Michael Kerin, Raymond McLoughlin, Carmel Malone, Karl Sweeney, Aoife Lowery
Background: Invasive lobular carcinoma accounts for 5–15% of all breast cancers. The aim of this study was to assess the clinical outcome and relapse profile of patients with Invasive Lobular Carcinoma cases at a university hospital in the west of Ireland.
Methods: A retrospective cohort study was performed on a prospectively maintained database of 455 invasive lobular carcinoma (ILC) cases at the University Hospital Galway from 1999–2013. Minimum of 5-years follow up required.
Results: A total of 455 ILC cases were analysed, 403 (88.6%) ER+, 339 (74.5%) PR+ and 344 (75.6%) HER2−, 175 (38.5%) T2, 189 (41.5%) N0, and 56 (12.4%) had bilateral presentation. The mean (SD) age of patients at diagnosis was 61.6 [13] years, and 325 (71.4%) of women were post-menopausal. Luminal A accounted for 348 (76.5%), and 32 (9.2%) luminal A patients had a disease recurrence at either a local or distant site. There was an even split between bone and non-bone disease recurrence. Of the 8 (1.8%) HER2+ patients, 4 of had a disease recurrence and 3 of these were non-bone locations. A total of 50 (10.9%) women had a disease recurrence, 15 (3.3%) of the patients are alive with disease recurrence and 33 (7.3%) had a disease recurrence and are now deceased. Bone, Liver, Lung and Brain were the most common sites of metastasis, favoring hormone receptor positive patients. Single site metastasis (n=13) occurred most commonly in bone at a median time of 62 months. Overall survival for these patients is a mean (SD) of 70.8 (33.8) months.
Conclusions: ILC cases tend to present in post-menopausal women most commonly with a grade II, estrogen and progesterone receptor positive, and HER2- tumor. ILC’s are prone to distant metastatic bony recurrence after five years of survival. Currently, 296 patients (>67 years) are still alive and are highly prone to disease recurrence.