The impact of external beam radiation therapy on shoulder surgical outcomes: a case series study

External beam radiation therapy (XRT) is a commonly used treatment adjunct in patients with breast cancer and is known to cause soft tissue dysfunction. However, data on XRT as a preoperative risk factor for shoulder surgery is limited. The purpose of this study was to assess whether prior history of breast cancer treated with XRT has an impact on surgical complications or outcomes. We hypothesize that patients treated with XRT will have a higher rate of surgical complications and lower outcomes.

A 20-year retrospective chart review across a large, academic health care system was performed. Inclusion criterion comprised any patient with history of breast cancer of the upper-outer or axillary region treated with XRT. Patients also must have undergone a surgical procedure to the ipsilateral shoulder with at least 1-year postoperative follow-up. Patients were stratified by demographics, hand dominance, and surgery type. Postoperative outcomes including range of motion (ROM) and visual analog scale (VAS) scores for pain were also collected.

Eighteen patients were identified (100% female) with an average age of 66.3 years (standard deviation 10.5 years). Ten shoulders underwent rotator cuff repair (RCR), 4 total shoulder arthroplasty (TSA), 3 reverse shoulder arthroplasty (RSA), and 1 arthroscopic superior labrum anterior to posterior (SLAP) repair. Four patients treated with RCR (40%) experienced postoperative complications related to their procedure. These included scapular winging, adhesive capsulitis, stiffness, and one retear. Two patients treated with shoulder arthroplasty (28.6%) experienced postoperative complications that included lymphedema and periprosthetic fracture following a mechanical fall in one RSA patient and periprosthetic infection in a TSA patient. ROM across all groups improved, most significantly in forward flexion and internal rotation among RCR patients (P < .001). Furthermore, a statistically significant improvement in VAS scores was achieved in each group (6.2 ± 2.14 preoperation, 1.06 ± 1.75 postoperation; P < .001).

When compared to national averages, complication rates in our cohort were higher (40% vs. 10%-17% in RCR patients and 28.6% vs. 4%-14% in arthroplasty patients). On further scrutiny, many of these complications were independent of a history of XRT and many resolved with appropriate therapy. Most importantly, functional outcomes as measured by ROM and pain scores showed appropriate improvement consistent with normal populations without history of XRT. Thus, our results suggest that performing shoulder surgery after ipsilateral XRT for breast cancer is likely safe and may offer improved pain and ROM compared to forgoing surgery without necessarily increasing the risk for postoperative complication.