Mirror Therapy for Phantom Breast Syndrome – Dr. Filipe Martins (EPFL)

This «allocated fund » was granted to Dr. Filipe Martins (EPFL) in February 2024 for one year

Breast cancer is the most frequently diagnosed cancer in women, with more than 6000 new cases diagnosed yearly in Switzerland; an incidence which is still increasing. Although still a leading cause of cancer-related death^1,2, mortality due to breast cancer has decreased considerably over the last decades^1,2, thanks to the implementation of mammography screening programs, surgery improvements, and more efficient medical treatments.

Approximately 40% of breast cancer patients must undergo a mastectomy to treat their disease³. Therefore, the management of long-term consequences of this surgical procedure is advocated, in order to limit the economic and societal impacts of its related morbidity and to improve the quality of life of cancer survivors.

Phantom breast syndrome (PBS), occurring after a mastectomy, is a condition characterized by a residual sensation associated with the removed breast tissue, accompanied by neuropathic pain (similar to phantom limb syndrome after amputation). Although of varying estimated incidence in the literature, its prevalence reaches up to 30% in patients having undergone this procedure³. Accordingly, 760 women are diagnosed with PBS in Switzerland every year. In addition to painful sensations described as shooting and burning, patients may also experience other discomforts, such as pins and needles, itching, tingling, pressure, and throbbing³. PBS severely affects the quality of life as a consequence of the physical disability and emotional distress it generates. Some studies demonstrated that depression, psychiatric morbidity, and fear of cancer recurrence are more important in women suffering from PBS³.

Parallels have been drawn between PBS and phantom limb syndrome, such as the timing of their installment after surgery. There are also clues that their development occurs on the same neurological basis. Research on PBS is still sparse and often inconclusive. However, it is increasingly clear that this condition has its own specificities. Therapeutic interventions for this type of pain include oral medications, such as opiates and antidepressants, in addition to topical agents. However, such medical treatments have limited efficacy once this type of chronic pain is installed. Similarly, preventive treatments aiming at reducing PBS incidence are currently not available. Patients are often isolated with their syndrome, as the awareness of the existence of PBS is limited outside of the specialized medical community, making the management of this syndrome a major unmet clinical need.

In this study, we aim to adapt “mirror therapy”, a common non-invasive treatment for phantom limb syndrome, for the care of PBS patients. This method, effective since the mid-1900s^4,5, relies on the usage of a mirror to hide the amputated limb and to replace its image with the reflection of the intact contralateral limb. By doing so, the patient’s brain is tricked by the visual perception of two functional limbs, which elicits cortical remodeling and subsequent neuropathic pain relief. After decades of research, the therapy has been improved and adapted using different combinations of physical mirrors and virtual reality.

This project aims at improving the quality of life and the performance status of women suffering from PBS thanks to non-invasive devices and accompanying physiotherapy sessions. The objective is to improve pain control and potentially reduce PBS-related disabilities and their economic and societal impacts. This project started a year ago, but requires substantial funding to achieve further improvements.