Dosimetric analysis of the brachial plexus among patients with breast cancer treated with post-mastectomy radiotherapy to the ipsilateral supraclavicular area: report of 3 cases of radiation-induced brachial plexus neuropathy

Abstract

BackgroundThe purpose of this study was to evaluate the brachial plexus (BP) dose of postmastectomy radiotherapy (PMRT) to the ipsilateral supraclavicular (ISCL) area, and report the characteristics of radiation-induced brachial plexus neuropathy (RIBPN).MethodsThe BP dose of 31 patients who received adjuvant PMRT to the ISCL area and chest wall using three-dimensional conformal radiotherapy (3DCRT) and the records of 3 patients with RIBPN were retrospectively analyzed based on the standardized Radiation Therapy Oncology Group-endorsed guidelines. The total dose to the ISCL area and chest wall was 50 Gy in 25 fractions.ResultsPatients with a higher number of removed lymph nodes (RLNs) had a higher risk of RIBPN (hazard ratio [HR]: 1.189, 95% confidence interval [CI]: 1.005-1.406, p = 0.044). In 31 patients treated with 3DCRT, the mean dose to the BP without irradiation to the ISCL area was significantly less than that with irradiation to the ISCL area (0.97 ± 0.20 vs. 44.39 ± 4.13 Gy, t = 136.75, p <0.001). In the 3DCRT plans with irradiation to the ISCL area and chest wall, the maximum dose to the BP was negatively correlated with age (r = −0.40, p = 0.026), body mass index (BMI) (r = −0.44, p = 0.014), and body weight (r = −0.45, p = 0.011). Symptoms of the 3 patients with RIBPN occurred 37–65 months after radiotherapy, and included progressive upper extremity numbness, pain, and motor disturbance. After treatment, 1 patient was stable, and the other 2 patients’ symptoms worsened.ConclusionsThe incidence of RIBPN was higher in patients with a higher number of RLNs after PMRT. The dose to the BP is primarily from irradiation of the ISCL area, and is higher in slim and young patients. Prevention should be the main focus of managing RIBPN, and the BP should be considered an organ-at-risk when designing a radiotherapy plan for the ISCL area.

The radiation dose tolerance of the brachial plexus: A systematic review and meta-analysis

“…Extensive surgery in the peri-plexal region has also been shown to increase the risk of RIBP [51]. The majority of included cohorts in our study involved breast cancer patients, a proportion of which may have undergone axillary surgery.…”

Radiation-Induced Brachial Plexopathy in Patients With Breast Cancer Treated With Comprehensive Adjuvant Radiation Therapy

“…Another modern case series reported a RIBP rate of 0.48% in a cohort of 629 patients with breast cancer receiving chest wall and ipsilateral SCV radiation with the CRT technique where the average D mean and D max to the brachial plexus in patients with RIPB were 47 Gy and 59 Gy, respectively. 5 Historical data on the development of brachial plexopathy in a large cohort of patients with early stage breast cancer by Pierce et al 10 reported a RIBP rate of 1.8% in patients receiving SCV radiation, 1.3% in patients with axillary dose of 50 Gy, 5.6% in patients with axillary dose > 50 Gy, and increased risk of RIBP with use of chemotherapy. In our study, all patients with RIBP in the CRT group received PAB, and 4 out of 5 patients with RIBP received adjuvant chemotherapy.…”

“…Chronic, rare toxicities such as radiation-induced brachial plexopathy (RIBP) have previously been associated with conventional RT to the breast and regional lymph nodes. 4 , 5 , 6 Therapy-related complications involving the upper extremity negatively affect patient quality of life. 7 However, studies evaluating long-term toxicities in patients receiving comprehensive RT with modern techniques are lacking.…”

Stem cell therapy for nerve injury

“…In 1%-3% of patients with a traumatic accident, a PNI will almost always be involved[ 3 , 4 ]. It has been recognized in children suffering falls[ 5 , 6 ], as a consequence of medical procedures such as surgeries, chemotherapy, radiation[ 7 - 9 ] and sometimes it has been brought about some chronic conditions like diabetes and cancers[ 10 , 11 ]. It can also occur as an iatrogenic injury[ 12 ].…”