Far infrared ray (FIR) therapy: An effective and oncological safe treatment modality for breast cancer related lymphedema.

Background: The incidence of breast cancer related lymphedema is approximately 5%. Far infrared ray (FIR) treatment can potentially reduce fluid volume and extremity circumference as well as the frequency of dermato-lymphangitis (DLA). However, there is no published data on the oncological safety of FIR and the potential for activation of any residual breast cancer cells. The aim of this study is to investigate the safety of far infrared ray (FIR) treatment of postmastectomy lymphedema, clinically and in vitro.

Methods: Patients who underwent mastectomy more than 5years ago complicated by upper extremity lymphedema for more than 1year were included. The enrolled patients were divided into an FIR treatment group and a control group (conservative treatment using bandage compression). Outcome measures included tumor markers (CA153, CA125), ultrasonography of relevant structures and monitoring for adverse reactions 1year after treatment. For the in vitro part of the study, the effects of FIR on human breast adenocarcinoma cell lines (MCF7, MDA-MB231) compared to the effects of FIR on human dermal fibroblasts as a control were considered. The viability, proliferation, cell cycle and apoptotic statistics of the adenocarcinoma and human dermal fibroblast cell lines were analyzed and compared.

Results: Results demonstrated that after treatment with FIR, tumor marker (CA153, CA125) concentrations in both the FIR and control groups were not elevated. There was no statistically significant difference between FIR and control group marker expression (p>0.05). Furthermore, no patients were diagnosed with lymphadenectasis or newly enlarged lymph nodes in these two groups. Importantly, there were no adverse events in either group. The in vitro experiment indicated that FIR radiation does not affect viability, proliferation, cell cycle and apoptosis of fibroblasts, MCF-7 and MDA-MB-231 cells.

Conclusions: FIR should be considered as feasible and safe for the treatment of breast cancer related lymphedema patients 5years after mastectomy. FIR does not promote recurrence or metastasis of breast cancer and is a well-tolerated therapy with no adverse reactions.