Radiation Induced Brachial Plexopathy

Chronic pain affects 1 in 4 US adults, and many cases are resistant to almost any treatment. Deep brain stimulation (DBS) holds promise as a new option for patients suffering from treatment-resistant chronic pain, but traditional approaches target only brain regions involved in one aspect of the pain experience and provide continuous 24/7 brain stimulation which may lose effect over time. By developing new technology that targets multiple, complimentary brain regions in an adaptive fashion, the investigators will test a new therapy for chronic pain that has potential for better, more enduring analgesia.

Radiation-induced brachial plexopathy (RIP) is a rare and severe delayed peripheral nerve complication of radiotherapy, that is spontaneously irreversible with no medical treatment to limit or reduce symptoms. The investigators planed in RIP a randomized double blind clinical trial, using a pentoxifylline (P)- tocopherol (E)- clodronate combination versus placebo, to assess a possible symptomatic regression by a sensory-motor neurological quantifiable and reproducible score (modified Subjective Objective Medical management Analytic, SOMA).
The investigators previously developed a successful PE treatment in symptomatic RI injuries via the antioxidant pathway, in clinical phase II and III trails and experiments obtaining a major significant radiation-induced fibrosis regression, then the PE clodronate combination (PENTOCLO), obtaining a rapid and significant healing of mandible osteoradionecrosis and significant neurological signs regression (- 35% modified SOMA score at 18 months) in 50 partial RIP.
The aim of this phase III randomized clinical trial is to show PENTOCLO efficiency and its tolerance in long survival patients irradiated before for cancer and presenting with partial RIP of upper or lower legs.
The investigators calculated to include 60 patients to show a significant clinical difference between the two groups after 18 months of treatment: PENTOCLO[Pentoxifylline 400 (2x/d) + vitamine E 500 (2x/d) + intermittent Clodronate 800 (2/d, 5d/7)] versus triple placebo, with prednisone 20 (2d/7) for all patients.
RIP is assessed before treatment and every 6 months by a standardized sensory-motor neurological (SOMA 95 modified by NCI-CTC 99) score used for main criteria at M18, and various neurological scales of assessment (Visual Analog Scale for pain / VAS for paresthesia, Neuropathic Pain Symptom Inventory [NPSI], Overall Disability Sum Score [ODSS], muscle testing, Nine hole peg test / Timed 25-Foot Walk), quality of life (SF36, Patient Global Impression of Change and Clinical Global impression of Change [PGIC/ CGIC]) and electrophysiology.