Morel, V., Joly, D., Villatte, C., Dubray, C., Durando, X., Daulhac, L., . . . Pickering, G. (2016). Memantine before mastectomy prevents post-surgery pain: A randomized, blinded clinical trial in surgical patients. PLOS One,11(4), e0152741. 

To determine if pre- and postmastectomy treatment with memantine can prevent neuropathic pain, impaired cognition, and decreased quality of life (QOL)

Memantine 5–20 mg or placebo was given daily for four weeks starting two weeks prior to mastectomy, with increasing doses during the first two weeks prior to mastectomy and maintained at 20 mg during two weeks after surgery. The control received placebo daily for four weeks starting two weeks prior to mastectomy. Assessment was baseline, two weeks prior to surgery, two weeks after surgery, and three and six months postop.

• N = 40   
• AGE = 18 years and older
• FEMALES: 100%
• CURRENT TREATMENT: Immunotherapy
• KEY DISEASE CHARACTERISTICS: Woman diagnosed with breast cancer
• OTHER KEY SAMPLE CHARACTERISTICS: Participants were aged 18 years or older, planned for mastectomy with or without axillary dissection, and were able to understand and follow protocol. Exclusions: contraindications for memantine and hypertension, severe cardiac insufficiency and/or diabetes, alcohol addiction, treatment with certain drugs, childbearing age, no use of effective contraceptive, pregnancy or lactation, involvement in another trial, inability to comply with protocol requirements

• SITE: Single site   
• SETTING TYPE: Inpatient    
• LOCATION: University Oncology Hospital, Clermont-Ferrand, France

• PHASE OF CARE: Active antitumor treatment
• APPLICATIONS: Elder care

• Randomized, single-blind, placebo controlled trial

• Numerical rating scale
• Brief Pain Inventory (BPI)
• McGill Pain Questionnaire (MPQ)
• Neuropathic Pain Diagnostic Questionnaire (DN4)
• Neuropathic Pain Symptom Inventory
• Trail Making Test (TMT)
• Digit symbol substitution test (DSST)
• Leeds Sleep Evaluation Questionnaire (LSEQ)
• Quality of life by the SF-36
• Surgical- and chemotherapy-induced neuropathic pain were differentiated.

A significant reduction in pain at three months postoperatively was noted (p = 0.017) and better ability to cope with pain was demonstrated (p = 0.032). No significant difference was noted at six months. Secondary outcomes for pain intensity showed no significant difference. A significant difference existed in use of antiepileptics for pain at M3 which was maintained up to M6 (M3, p = 0.04; M6, p = 0.04) with overall significant time difference (p = 0.041). Pain was significantly less for those receiving chemotherapy at M3 (p = 0.04) and M6 (p = 0.009). In addition, chemotherapy-induced paresthesias/dysesthsias was significantly reduced at M3 compared to the day of inclusion (p = 0.01). No significant difference was noted in cognitive function or QOL. No significant difference was noted in regards to LSEQ; however, significance was noted for behavior following wakefulness at M6 (p = 0.038).

Memantine can potentially reduce post-mastectomy and chemotherapy-induced nerve pain while limiting polypharmacy and comorbidity associated with the current treatment approach. This approach would need to be demonstrated in a larger population, with a longer term follow-up and potential dosing change.

• Small sample (< 100)
• Findings not generalizable
• Not generalizable to all chemotherapy patients nor surgical patients for treating neuropathic pain

Nurses would need to be educated on use of memantine for pain control and the potential side effects. Patient education would be required to help the patients understand the use of this medication for treatment of pain. Results of the effects of this approach may be limited.