Quantitative Sensory Testing in Women After Surgery for Breast Cancer: A Systematic Review and Narrative Synthesis.

Objectives: Quantitative sensory testing (QST) is a noninvasive technique to evaluate functioning of the somatosensory system. In many women surgically treated for breast cancer (BC), somatosensory functioning is disturbed with high prevalence of sensory loss and/or pain. The aims of this systematic review were (1) to summarize literature about QST methods; (2) to summarize the results within women surgically treated for BC (patients and survivors); (3) to compare QST results between women surgically treated for BC with and without pain; and (4) to compare the results between women surgically treated for BC and women without history of BC.

Methods: A systematic literature search was conducted up to February 2020. Included studies had to report on QST methods (mechanical or thermal detection-pain thresholds, pressure pain thresholds [PPT], temporal summation [TS], or conditioned pain modulation [CPM]) in women over 18 years with-without pain, who had undergone unilateral surgery for BC.

Results: Twenty-eight studies were included. Discrepancies in QST methods were greatest for TS and CPM. A local disturbance in thermal detection and an increased pain facilitation were found in BC survivors with pain in the surgical area. BC survivors with upper limb pain had significantly lower PPT at the surgical area and PPT were also significantly lower compared with women without history of BC, at affected and nonaffected sides for both local and remote body regions.

Discussion: Standardized QST incorporating assessments of CPM is warranted in order to draw conclusions about neurobiological mechanisms of pain and somatosensory disturbances after surgical treatment for BC and to enhance mechanism-based management of these sequelae.