Patients submitted to radiotherapy or chemotherapy induced antineoplastic therapy have as their sequel oral mucositis, which is the main complication arising from the treatment. Laser therapy is a modality that has grown in recent years, with evidences of significant improvements in the prevention and treatment of oral mucositis. This study aims to show the benefits of low-level laser therapy application in patients submitted to antineoplastic therapy and present oral mucositis by means of an integrative literature review on the use of low-level laser to prevent and treat the lesion. A literature review was conducted with seven publications in Portuguese and English in PubMed and SciELO databases, from 2008 to 2018 and a summary table was prepared. It was observed that low-level laser therapy is an effective tool in the prevention and treatment of oral mucositis in cancer patients, bringing benefits such as: reduction of pain and severity of the lesion and anti-inflammatory, analgesic and healing effects.
Keywords: Laser Therapy; Oral Mucositides; Cancer patients
Through radiotherapy or chemotherapy, the antineoplastic treatment can cause cellular damage to the oral epithelium and salivary glands, as well as changing its functions and causing lesions, such as oral mucositis .
Oral Mucositis (OM) is an inflammation and ulceration of the oral mucosa, which becomes swollen and erythematous and may lead to the formation of large ulcers covered by pseudomembrane. This lesion is extremely painful and causes discomfort, dysphagia and systemic weakness, as well as being the most common cause of pain in the mouth in cancer patients [2-4].
Due to difficult feeding and speech, the ulcerations resulting from OM can increase the risk of local and systemic infection and can compromise oral function and interfere with antineoplastic treatment. It also may increase hospitalization stays time and influence the nutritional status of the patients. Lesions appear around 7 to 10 days after chemotherapy and generally from the second week of radiotherapy[3,5,6].
Some chemotherapy drugs are used alone or associated with radiotherapy in the hospital scope are responsible for the appearance of OM lesions, because they act mainly on tumor cells and affect the tissues of oral mucosa that result from immunosuppression. And due to the great sensitivity of the oral tissues and toxic effects of the chemotherapy drugs, lesions in oral cavity are the most common arise from chemotherapy .
And 5-fluorouracil, methotrexate, melafalan, cyclophosphamide, etoposide, mitoxantrane and cytarabine are the most common chemotherapy drugs [6,7]. Amoung these drugs, 5-fluorouracil, methotrexate and cyclophosphamide are the most related to the appearance of OM [3,6] in patients undergoing antineoplastic treatment.
The main clinical diagnosis of the severity of the OM is indicated by World Health Organization in scales varying from grade 0 to grade 4, respectively: normal mucosa; erythematous mucosa; ulcer involvement and difficulty in solid feeding; presence of extensive ulcer and feeding of liquid consistency . In 2014, the Multinational Association of Support Care in Cancer/International Society of Oral Oncology (MASCC/ISOO) has recommended low-level laser therapy because of its benefits as a form of OM prevention in patients who has received hematopoietic stem cells .
The photodynamic laser therapy, more specifically low-level laser therapy (LLLT), has been used in prevention and treatment of OM in recent years [10-12].The application of LLLT on OM has biological effects through photophysical and biochemical processes, increasing the cellular metabolism by stimulating mitochondrial activity. The result is an anti-inflammatory, analgesic and cicatrizator effect of lesions in the mucos  and collagen and elastin production, contraction of the wound and acceleration of healing, keeping the integrity of the mucosa .
A systematic review and meta-analysis  has showed
a strong association in the treatment of OM by low-level red
and infrared laser therapy, which had the potential to partially
suppress the development of the OM induced by antineoplastic
therapy and significantly reduced pain, severity of the lesion and
duration of symptoms. Although laser therapy is demonstrating
a considerable level of efficacy in reducing the grade of OM in
patients undergoing antineoplastic therapy [12,15,16] there are
still no established protocols for the treatment of OM in cancer
patients . Nevertheless, studies have suggested that laser
therapy could be used as a form of prevention and treatment of
the OM lesions induced by the treatment of cancer [13,18,19].
That way, Bensadoun and Nair  proved that there are
consistent and favourable evidences to LLLT, as long as from
an ideal dose, and present as an accessible possibility for the
tratment of OM induced by antineoplastic therapy. The authors
still revealed that there is a possibility of LLLT become a part of
the regular oral care in treatment of cancer. Thus, this study aims
to show the benefits of the application of LLLT in cancer patients
that present OM, through an integrative review of literature about
the use of this laser as an preventive measure and OM treatment.
The integrative review is a descriptive research method
where it can search, critically evaluate and synthesize the
available evidences about the theme, in order to show the current
knowledge of the subject investigated, to intervene effectively in
health care and to reduce costs, to identify gaps directed to the
development of future research .
It should be emphasized that the integrative review
contributes to the process of research and analysis of the results,
aiming to increase of a specif topic based in other social studies
already published. This methodology of integrative review of
the literature allows the accomplishment of successful analyzes
on the data collection and information, besides the diagnosis
and presentation of the results of the beginning of the study. A
literature review of the publications in Portuguese and English
was conducted in PubMed and SciELO databases, from 2010
to 2018, using descriptors according to DeCs (Bireme Health
Descriptors) related to: laser, oral mucositis and cancer patients.
After the identification of 10 (ten) articles, an exploratory
reading of the abstracts was conducted in order to verify if the
article fit the theme. Then, 7 (seven) articles were selected for
analysis and subsequent discussion.It was excluded articles
that did not have the inclusion criteria, those that presented
duplication amoung databases and articles that after detailed
reading did not have the objective proposed in this review.
A table was prepared with the purpose of synthesizing and
comparing the obtained data. In relation to the ethical aspects,
there was the concern to register the necessary information to
the identification of the authorship of the investigated articles
and the care of changing nothing about the available information
in the articles analyzed.In the last decades, due the evolution of
treatments in cancer patients and with the research for better
conditions to them, the photodynamic therapy, more specifically
LLLT emerged as na ally with the prevention and treatment of OM
induced by antineoplastic treatment [10-12].
Khouri et al. conducted a study in Ribeirão Preto, Brazil,
that has showed significant improvements through the use of
laser therapy in prevention and treatment of OM. The laser
therapy provided pain relief, inflammation control, maintenance
of the integrity of oral mucosa, tissue repair and patient comfort.
n 2012, a systematic review and meta-analysis  confirmed
the information from Khouri study . This systematic review
evaluated the interaction between laser therapy and OM and
found strong evidences regarding the efficacy of low-level red
and infrared laser therapy in the development of OM induced by
antineoplastic therapy. The study also found that the laser therapy
would have significantly reduced the pain, severity and duration
of the lesions symptoms.
Other systematic review  compared light and laser
therapies in the treatment of OM in cancer patients. They
concluded that the evidences were favorable to laser therapy and
that the studies about the efficacy of laser therapy were raising.
That way, Figueiredo et al. pointed significant prophylatic
effects on OM with a degree greater than three submitted to laser
Previous studies [13,14,18] were confirmed by a systematic
revie  that revealed LLLT reduced the severity of lesions and
pain in cancer patients when laser was applied as a prophylatic
measure. And due the care about possible adverse effects of
laser therapy, Bensadoun and Nair  reviewed the literature
and conclued that no adverse effects have been reported from
the use of LLLT in prevention and treatment of OM induced by
In addition, Bensadoun and Nair  revealed there are
moderate to strong evidences in favor of the application of lowlevel
laser in ideal doses as an cheap and eficiente alternative for
OM induced by antineoplastic therapy. The authors also predicted
that laser therapy would become a part of the oral care routine in
Migliorati et al. corroborated with Bensadoun and Nair 
and conclued that the application of LLLT had the potential to
become routine of care practice in combat OM. That way, in
2014 the Multinational Association of Support Care in Cancer/
International Society of Oral Oncology (MASCC/ISOO) has
recommended LLLT  in its guide as an intervention in OM. The
guide is based on strong evidences that supported the treatments
in situations indicated by the guide: LLLT (wavelength up to
650nm, power of 40mW and a tissue energy of 2 J/cm²) in the
prevention of OM in patients who transplanted hematopoietic
cells after conditioning with high dose of chemotherapy, with or
without total body irradiation. And with reduced evidences, the
guide recommended LLLT (wavelength about 632.8nm) in the
prevention of OM in patients submitted to radiotherapy without
concomitant chemotherapy for head and neck cancer.
Bensadoun e Nair  has recommended the treatment with
LLLT should be repeated every day, every other day or at least
three times a week until the wound heals. Nevertheless, although
the laser therapy is demonstrating a reduction in OM in patients
undergoing antineoplastic therapy [12,15,16], a protocol to be
followed in the treatment of OM in cancer patients has not yet
been established .
Finally, a systematic review  analyzed the effects of LLLT
in OM induced by antineoplastic theray in pediatric and young
patients. The findings corroborate with other studies in adults
[12-14,18] in order to reduce pain and severity of OM, providing
relief of symptoms and being na excelente option for prevention
and treatment of OM.
Several systematic reviews have proved by strong associations
the efficacy of laser therapy in treatment and prevention of OM
[12,14,17,21]. In addition, all articles consulted have presented
favorable results for the use of laser therapy in prevention and
treatment of OM induced by antineoplastic treatment.Thus, the
laser therapy is a promissing and effective tool for prevention and
treatment of OM in cancer patients and it brings benefits such as
reduction of pain and severity of the lesion and anti-inflammatory,
analgesic and healing effects.It is believed that soon laser therapy
will be a mandatory part of the care protocol for OM prevention
and treatment, although protocols established in the researched
literature have not been found.