Laurie's Blogs.

By Peter Jenkins, MBA– www.spectravet.com

The question of laser therapy (aka photobiomodulation - PBMT) vs cancer is a common one, and, typically, you'll see cancer and neoplasia listed as contraindications for laser therapy. 

However, it's not always the case that laser treatment should be withheld from patients with known or suspected cancer, nor that irradiation of a tumor mass itself is necessarily contraindicated.

There is nothing in the literature specifically regarding laser therapy and osteosarcoma, but there are studies with other cancers. There are also numerous studies into the benefits of PBMT in the treatment and prevention of oral mucositis in patients undergoing radiation and chemotherapy for e.g. leukemia, head and neck cancer, lymphoma, and acute lymphoblastic leukemia, all of which demonstrate safety and efficacy.

I would take every case individually, of course, but, as a general rule, using LLLT/PBMT on patients with known or suspected neoplasia or tumors is not specifically contraindicated, and post-op PBMT following tumor removal would probably be more beneficial than not; possibly even if the margins aren't clean. 

When in doubt, you could utilize distal/systemic effects by irradiating regional lymph nodes, and also any volume of tissue through which blood flows to the surgical site. You can also irradiate between the spinal segments over the applicable dorsal roots. 

On a cautious note, borne from experience with our own dog, Phoenix, who we lost to osteosarcoma in 2016, I would be careful irradiating directly over the lesion site, at least initially. 

We initially thought P-dog had muscle soreness due to some rough-housing with a Cane Corso we'd fostered. After consulting with our vet, who uses laser in his practice, we started lasering Phoenix's shoulder and upper leg. However, whenever I irradiated the upper end of the humerus he'd flinch and withdraw in obvious pain. 

In 19 years (at that time) I'd never seen a reaction like this. I tried a non-contact technique, but it made no difference. I thought it quite significant, too, that he did not react when the laser was applied but not switched on. 

This led us back to the vet, who performed a biopsy. Unfortunately, we got the news we'd been wishing we wouldn't. 

Now, a single case isn't much to go by, and I don't know whether, in our case, laser irradiation was causative in relation to P-Dog's increased pain, but I suspect it was. So now I advise that, if a patient reacts to laser application with an immediate increase in pain, do some more digging.

From the literature:

In Vitro: There's been a number of studies [Sperandio et al, 2013 (1); Gomes Henriques et al, 2014 (2)] which have shown that laser irradiation can cause tumor cell proliferation, while others [Schartinger et al, 2012 (3); Berns 1988 (4); McGuff, 1965 (5), 1966 (6) & 1966 (7)] have found that laser therapy does not exhibit a tumor-promoting effect. 

In Vivo: Three studies [Frigo et al, 2009 (8); Rhee et al, 2016 (9); Ottaviani et al, 2016 (10)] have demonstrated that tumor mass can increase after laser irradiation in vivo, but, in two of these [Frigo et al, 2009 (8); Ottaviani et al, 2016 (10)], anti-cancer effects were also shown. 

Frigo et al (8) studied an in vivo mouse model of melanoma. A control group (n=7) received no irradiation. The active groups received daily transdermal irradiation for three days with a 50 mW continuous wave 660 nm laser, beam spot 0.02 cm2 (2.5 W/cm2), at two doses: 

a. Low-Dose Group (n=7) was irradiated for 60 secs and received 3 J (150 J/cm2) per treatment session. Tumors in the low-dose group reduced (insignificantly) in size compared to the control group.

b. High-Dose Group (n=7) was irradiated for 420 secs and received 21 J (1050 J/cm2) per treatment session. The total tumor mass volume in this group increased significantly versus control.

Rhee et al (9) studied an in vivo mouse model of human anaplastic thyroid carcinoma. A control group (n=10) received no irradiation. The two active groups each received a single direct irradiation to the surgically-exposed thyroid with a 2 mW continuous wave 650 nm laser, beam spot 0.02 cm2 (100 mW/cm2), at two doses:

a. Low-Dose Group (n=10) was irradiated for 150 secs and received 0.3 J (15 J/cm2). Tumors in the low-dose group increased significantly in size compared to the control group.

b. High-Dose Group (n=10) was irradiated for 300 secs and received 0.6 J (30 J/cm2). The total tumor mass volume in this group increased significantly versus both control and the low-dose group.

Ottaviani et al (10) studied both melanoma and oral carcinoma in mice, with three different sets of laser parameters:

a. L1: Wavelength 660 nm, laser power 100 mW, irradiance 50 mW/cm2, fluence 3 J/cm2, time 60 s, continuous wave.

b. L2: Wavelength 800 nm, laser power 1 W, irradiance 200 mW/cm2, fluence 6 J/ cm2, time 30 s, continuous wave.

c. L3: λ 970 nm, laser power 2.5 W, irradiance 200 mW/cm2, fluence 6 J/cm2, time 30 s, continuous wave.

Irradiation was performed daily for four days. A control group for each of the cancer types received no irradiation. Tumor growth continued in all active groups, but the growth rates of the tumors were significantly decreased in all groups versus control. This result was attributed to a 'normalisation' of tumor vasculature and an increase in immune cell activation.

1. Sperandio et al (2013) Low-level laser therapy can produce increased aggressiveness of dysplastic and oral cancer cell lines by modulation of Akt/mTOR signaling pathway. J Biophotonics. 2013 October ; 6(10): 839-847

2. Gomes Henriques et al (2014) Low-level laser therapy promotes proliferation and invasion of oral squamous cell carcinoma cells. Lasers Med Sci (2014) 29:1385-1395 

3. Schartinger et al (2012) Differential responses of fibroblasts, non-neoplastic epithelial cells, and oral carcinoma cells to low-level laser therapy. Abstract:https://www.ncbi.nlm.nih.gov/pubmed/21340656

4. MW Berns, JS Nelson. Laser applications in biomedicine. Part I: biophysics, cell biology, and biostimulation J Laser Appl 1988;1:34-39.

5. PE McGuff, RA Deterling Jr, LS Gottlieb. Tumoricidal effect of laser energy on experimental and human malignant tumors. New Engl J Med 1965;273:490-492.

6. PE McGuff, RA Deterling Jr, LS Gottlieb. Laser radiation for metastatic malignant melanoma. JAMA 1966;195:393-394.

7. PE McGuff, LS Gottlieb, I Katayama, CK Levy. Comparative study of effects of laser and/or ionizing radiation therapy on experimental or human malignant tumors. Am J Roentgenol Radium Ther Nucl Med 1966;96:744-748.

8. Frigo L, Luppi JS, Favero GM, et al. The effect of low-level laser irradiation (In-Ga-Al-AsP - 660 nm) on melanoma in vitro and in vivo. BMC Cancer. 2009;9(1):404-408. doi:10.1186/1471-2407-9-404

9. Rhee Y-H, Moon J-H, Choi S-H, Ahn J-C (2016) Low-Level Laser Therapy Promoted Aggressive Proliferation and Angiogenesis Through Decreasing of Transforming Growth Factor-b1 and Increasing of Akt/Hypoxia Inducible Factor-1a in Anaplastic Thyroid Cancer. Photomed Laser Surg 34:229-235

10. Ottaviani et al (2016) Laser Therapy Inhibits Tumor Growth in Mice by Promoting Immune Surveillance and Vessel Normalization. EBioMedicine 11 (2016) 165-172

Author’s Biography

Peter A. Jenkins, MBA, began his exciting and ongoing adventure in the world of laser therapy & photobiomodulation in Australia in 1996. His technical background includes the specification and development of laser devices for safety, reliability, affordability and efficacy, and he is driven to create technologies that enable practitioners to optimize their patients’ clinical outcomes. A passionate educator, and co-author of a number of peer-reviewed articles, Peter sees market education as the key to improving standards in the laser therapy/photobiomodulation industry and holding manufacturers and marketers accountable for the claims they make. 

Professional Positions

•Spectra-Medics Pty Ltd (Founder, Managing Director)

•SpectraVET, Inc. (Co-Founder, Dir. Education & Technology)

•Immunophotonics, Inc. (Co-Founder, Technology Advisor)

Honorary Positions

•Co-Founder & Council Member, Australian Medical Laser Association Inc

•Co-Founder, Co-Editor, The Annals of Laser Therapy Research

•Committee Member, Standards Australia HE3-12/003 (Medical Laser Safety)

•Peer Reviewer, Photomedicine & Laser Surgery

•Peer Reviewer, Lasers in Surgery & Medicine

•Peer Reviewer, Photochemistry & Photobiology

•Peer Reviewer, Dose-Response

•Past President (1998-9), Hornsby and District Chamber of Commerce & Industry Inc

Qualifications

•Master of Business Administration (University of Western Sydney) 1997

•Avionics Technician (Royal Australian Air Force) 1992

•Instrument Fitter (Royal Australian Air Force) 1984