ABSTRACT
Breast cancer-related lymphedema (BCRL) occurs in ~ 40% of patients after axillary lymph node dissection (ALND), radiation therapy (RT), or chemotherapy. First-line palliative treatment utilizes compression garments and specialized massage. Reparative microsurgeries have emerged as a second-line treatment, yet both compression and surgical therapy are most effective at early stages of LE development. Identifying patients at the highest risk for BCRL would allow earlier, more effective treatment. Perometric arm volume measurements, near-infrared fluorescent lymphatic imaging (NIRF-LI) data, and blood were collected between 2016 and 2021 for 40 study subjects undergoing treatment for breast cancer. Plasma samples were evaluated using MILLIPLEX human cytokine/chemokine panels at pre-ALND and at 12 months post-RT. A Mann-Whitney t-test showed that G-CSF, GM-CSF, IFN-2α, IL-10, IL-12p40, IL-15, IL-17A, IL-1ß, IL-2, IL-3, IL-6, and MIP-1ß were significantly higher at pre-ALND in those presenting with BCRL at 12 months post-RT. MIP-1ß and IL-6 were significantly higher at pre-ALND in those who developed dermal backflow, but no BCRL, at 12 months post-RT. Plasma IL-15, IL-3, and MIP-1ß were elevated at 12 months after RT in those with clinical BCRL. These findings establish BCRL as a perpetual inflammatory disorder, and suggest the use of plasma cytokine/chemokine levels to predict those at highest risk.
ABSTRACT
Introduction: The first high-quality clinical trial to support ultrahypofractionated whole-breast irradiation (ultra-HF-WBI) for invasive early-stage breast cancer (ESBC) was published in April 2020, coinciding with the beginning of the COVID-19 pandemic. We analyzed adoption of ultra-HF-WBI for ductal carcinoma in situ (DCIS) and ESBC at our institution after primary trial publication. Methods and Materials: We evaluated radiation fractionation prescriptions for all patients with DCIS or ESBC treated with WBI from March 2020 to May 2021 at our main campus and regional campuses. Demographic and clinical characteristics were extracted from the electronic medical record. Treating physician characteristics were collected from licensure data. Hierarchical logistic regression models identified factors correlated with adoption of ultra-HF-WBI (26 Gy in 5 daily factions [UK-FAST-FORWARD] or 28.5 Gy in 5 weekly fractions [UK-FAST]). Results: Of 665 included patients, the median age was 61.5 years, and 478 patients (71.9%) had invasive, hormone-receptor-positive breast cancer. Twenty-one physicians treated the included patients. In total, 249 patients (37.4%) received ultra-HF-WBI, increasing from 4.3% (2 of 46) in March-April 2020 to a high of 45.5% (45 of 99) in July-August 2020 (P < .001). Patient factors associated with increased use of ultra-HF-WBI included older age (≥50 years old), low-grade WBI without inclusion of the low axilla, no radiation boost, and farther travel distance (P < .03). Physician variation accounted for 21.7% of variance in the outcome, with rate of use of ultra-HF-WBI by the treating physicians ranging from 0% to 75.6%. No measured physician characteristics were associated with use of ultra-HF-WBI. Conclusions: Adoption of ultra-HF-WBI at our institution increased substantially after the publication of randomized evidence supporting its use. Ultra-HF-WBI was preferentially used in patients with lower risk disease, suggesting careful selection for this new approach while long-term data are maturing. Substantial physician-level variation may reflect a lack of consensus on the evidentiary standards required to change practice.