Risk-reducing surgery in PALB2 mutations carriers with breast cancer: a case series and literature review

Inherited germline mutations in PALB2 are known to predispose patients to a higher risk of breast, ovarian and pancreatic cancer with an estimated risk of developing breast cancer in over half of all affected women by age 80 years. Current guidelines for screening patients with PALB2 mutations include annual mammograms beginning at age 30 years and consideration of breast magnetic resonance imaging (MRI) and tomosynthesis. Existing evidence regarding risk-reducing surgery with mastectomy is insufficient to make a definitive recommendation to patients. In this case series, we describe the presentation and management of 5 patients with unilateral breast cancer and PALB2 mutations. To our knowledge, this is the first reported case series discussing the role of contralateral risk-reducing mastectomy (CRRM) in breast cancer patients with PALB2 mutations. The aim of our study was to evaluate the challenges in managing breast cancer risk in patients with PALB2 pathogenic variants with illustration through real-world clinical cases and a review of the literature.

In this retrospective observational study, we present 5 patients with PALB2 mutations between the ages of 29 and 61 years who were diagnosed with breast cancer and underwent surgical management of their breast cancer at our institution between November 2020 and March 2022. Through their clinical courses and a literature review, we discuss the role of CRRM in breast cancer patients with PALB2 gene mutations.

Out of the 5 patients, 3 patients underwent CRRM and 2 patients chose unilateral surgery for their breast cancer and active surveillance for the contralateral breast. Of the 3 patients who underwent CRRM, 1 patient experienced a surgical complication from reconstruction on the prophylactic side. None of the patients developed any recurrences with an average length of follow up of 15.4 months.

Based on our experience and the currently available literature, CRRM in patients with a PALB2 mutation should be performed on a case-by-case basis through a shared decision-making process taking into consideration overall risk, family history, patient preference and quality of life.