Effectiveness of Botulinum Toxin A for Persistent Upper Limb Pain After Breast Cancer Treatment: A Double-Blinded Randomized Controlled Trial

Abstract

A single BTX-A infiltration in combination with an individual physical therapy program significantly decreased pain intensity at the upper limb in breast cancer survivors up to 6 months. However, the effect size was not clinically relevant, and no other beneficial effects were found.

The effectiveness of Botulinum Toxin A for treatment of upper limb impairments and dysfunctions in breast cancer survivors: A randomised controlled trial

“…This is the first randomized controlled trial investigating the effectiveness of BTX-A on upper limb impairments and dysfunctions after breast cancer. Despite the beneficial effects on pain intensity reported in a previous study (De Groef et al, 2018), no significant nor clinically relevant differences were found between groups. For the first outcome parameter 'shoulder mobility' improvements in both groups were found, in particular for forward flexion ROM.…”

“…As indicated in previous studies, pain and upper limb impairments are complex and difficult to treat. (De Groef et al, 2018, De Groef et al, 2015, De Groef et al, 2017a, De Groef et al, 2017c, De Groef et al, 2017d Similar as in these previous studies it appears that a certain subgroup of patients responds well to the intervention while others do only partly or not at all. An individually tailored approach is needed to increase effectiveness of the applied physical therapy modalities and other interventions such as BTX-A.…”

“…More details of this primary outcome and other pain-related secondary outcome parameters are mentioned elsewhere. (De Groef et al, 2018) The present study indicates that the beneficial effects on pain are not translated into improvements of upper limb impairments and function. Given the complex nature of upper limb problems after breast cancer, other mechanisms can contribute to the upper limb impairments such as myofascial dysfunctions, Axillary Web Syndrome, scar tissue, nerve damage and lymphedema.…”

“…Sample size calculation was performed for the primary outcome 'pain intensity at the upper limb region' of which results are published elsewhere. (De Groef et al, 2018) The current study analyzed secondary outcome parameters of this larger randomized trial.…”

“…However, the effect size was not clinically relevant. (De Groef et al, 2018) To our knowledge, no studies have investigated the effect of BTX-A on upper limb impairments and dysfunctions in the overall breast cancer patients. Therefore, the aim of the present study is to investigate the added value of a single BTX-A infiltration in the major pectoralis muscle to the current evidence based physical therapy modalities for treatment of upper limb impairments after breast cancer treatment.…”