Photobiomodulation by a new optical fiber device: analysis of the in vitro impact on proliferation/migration of keratinocytes and squamous cell carcinomas cells stressed by X-rays

Effect of low-level light therapy before radiotherapy in oral squamous cell carcinoma: An in vitro study

Radiation therapy for head and neck squamous cell carcinoma (HNSCC) is associated with several complications. Although photobiomodulation (PBM) has radioprotective effects in normal tissue, it could also enhance the growth of neoplastic cells. Thus, the present study aimed to investigate the cellular response of oral squamous cell carcinoma with pre-exposure to low-level phototherapy before radiotherapy. SCC9, Cal-27, A431, and HaCaT cell lines were subjected to low-level light therapy and radiotherapy. The cells were treated with a single energy density (300 J/cm²) of a light-emitting diode (660 nm) prior to ionizing radiation at different doses (0, 2, 4, and 6 Gy). After 24 h, wound scratch, proliferation, clonogenic cell survival, cell death, and reactive oxygen species (ROS) analyses were performed to evaluate cell response. The cell lines pre-exposed to PBM at the analyzed dosage were radiosensitive. The treatment significantly reduced cell proliferation and clonogenic cell survival. Migration and cell death assays also revealed positive results, with the treatment group showing lower rate of migration and higher cell death than did the control group. Moreover, PBM effectively increased the intracellular levels of ROS. PBM at 300 J/cm² is a promising radiosensitizing modality to reduce the radiation dose and avoid the intolerable side effects of radiotherapy for HNSCC, thus increasing the probability of successful treatment. However, further studies are needed to support and confirm the results.

[Low-level laser therapy in oncology - what's new? Analysis of 2018-2021 publications]

Low-level laser therapy (LLLT) is included in the Federal project «Fight against oncological diseases», which provides for equipping all specialized medical institutions in Russia with the appropriate devices until 2026.

PURPOSE OF THE STUDY

Publications analysis on the use of LLLT in oncology.

MATERIAL AND METHODS

To search for publications, databases and libraries were used: PubMed, Scopus, ResearchGate, Google Scholar, J-STAGE, eLibrary.ru for the period 2018-2021. For analysis, publications were selected that are of interest from the point of view of improving the methodology of LLLT, the prospects for the development of this method in the prevention, treatment and rehabilitation of patients. A total of 223 publications were found, including 39 reviews and meta-analyses, mostly in English (165) and Portuguese (41).

RESULTS AND DISCUSSION

The inclusion of LLLT in the ISOO/MASCC/ASCO recommendations for the treatment of complications such as mucositis, salivary gland hypofunction and xerostomia caused by non-surgical methods of treating cancer patients should be considered as a promising trend. An extremely low level of quality of LLLT techniques was noted, most often the replacement with meaningless «doses», «fluences» instead of the necessary parameters: wavelength, operating mode, power, frequency, exposure, etc. The use of only local illumination instead of systemic methods of LLLT does not allow obtaining the best results of treatment and prevention. Eliminating the shortcomings of treatment protocols with a focus on Russian experience, when laser blood illumination (intravenously or externally) and laser acupuncture are also necessarily carried out with local illumination of the lesion, will bring the effectiveness of LLLT to a qualitatively new, higher level.

New photobiomodulation device for prevention and cure of radiotherapy-induced oral mucositis and dermatitis: results of the prospective Safe PBM study

Purpose

The study aims to assess the feasibility, safety, and tolerability of CareMin650, a new photobiomodulation device, in patients treated by radiotherapy (RT) and to collect preliminary data on efficacy for prevention and treatment of oral mucositis (OM) and radiation dermatitis (RD).

Methods

Safe PBM is a French, multicentric, prospective, non-comparative study which include patients with head and neck cancer (H&NC, cohort A) or breast cancer (BC, cohort B) treated in prophylactic (cohorts A1 and B1) or curative setting (cohort A2 and B2). Prophylactic treatment was administered from D1 to end of RT, at a dose of 3 J/cm². Curative treatment started when a grade 1 to grade 3 lesion had occurred and was pursued until end of RT. Primary endpoint was incidence of device-related adverse events (AEs). OM and RD lesions were graded according to CTCAE V3.

Results

Overall, 72 patients were included (22, 9, 23, and 18 in cohorts A1, A2, B1, and B2, respectively). No device-related AE was reported after 1312 CareMin650 sessions. In cohorts A1 and B1, median time to first OM or RD lesion was 20 days. One BC patient developed G3 RD after completion of RT and discontinuation of CareMin650. Four H&NC patients developed G3 OM. In cohorts A2 and B2, lesions improved or stabilized in 71% of patients. Rates of satisfaction were high among patients and users.

Conclusion

CareMin650 is feasible, safe, and well tolerated for preventive or curative treatment of OM and RD in cancer patients treated with RT. Preliminary efficacy results are promising.

Supplementary Information

The online version contains supplementary material available at 10.1007/s00520-021-06574-2.