Page 358 - Withrow and MacEwen's Small Animal Clinical Oncology, 6th Edition

336 PART III Therapeutic Modalities for the Cancer Patient

were sustained for at least 16–18 hours postintervention.” 108 in a manner that stimulates cellular function and produces clinical
Massage also showed benefit in terms of mood, muscle relaxation, benefits. It contrasts with laser surgery, which destroys tissue.
In contrast to acupuncture, in which input begins with the
and sleep quality.
VetBooks.ir sage for children with cancer found that patients experienced less microtraumatic mechanical effects of the needle on local tissue,
A 2017 systematic review of controlled clinical trials on mas-
LT relies on the absorption and scattering of light within tissue.
pain, nausea, stress, anxiety, and immune suppression. 109 These LT imparts a monochromatic, narrow-band, coherent light source.
findings comport with assessments of the effects of massage in Photons from the laser support endogenous processes that involve
adults both with and without cancer. cell division and proliferation; this is one of the main reasons why
cancer has been considered a relative contraindication for PBM.
How Does Massage Work? Physiologic responses from LT’s PBM include increased phago-
Based on the rapidly expanding paradigm of autonomic neuro- cytosis; vasodilation; increased rate of regeneration of lymphatic
modulation and the desire by medical massage therapists to explain and blood vessels; stimulation of enzyme activity at the wound
how their treatments work, a unifying theory is beginning to edges; fibroblast stimulation; keratinocyte and fibroblast prolifera-
emerge that helps explain the effects of massage on diverse bodily tion; scar and keloid reduction; increased adenosine triphosphate
activities, such as digestion, emotional states, sleep, weight regula- (ATP) and DNA synthesis; and stimulation of muscle, tendon,
tion, pain control, and immune function. 110 Ordinarily, animals and nerve regeneration. 112 Clinically, PBM provides safe and cost-
suffering from acute and chronic illness exhibit heightened sympa- effective treatment for wound healing, neurologic recovery, pain
thetic tone that can cause maladaptive changes. The complemen- reduction, and lymphedema control. 113
tary, dualistic reciprocity encoded within the ANS dictates that as With respect to oncologic care, a growing body of evidence sug-
parasympathetic tone increases, sympathetic (fight-or-flight) activ- gests that LT may help alleviate oral mucositis. A 2007 Phase III,
ity diminishes. Consequently, reducing sympathetic hyperactivity randomized, double-blind, placebo-controlled clinical trial that
by means of massage can benefit patients by countering peripheral evaluated the efficacy of LLLT for the prevention of oral mucositis
vasoconstriction, inflammation, muscle tension, spinal cord wind- (OM) indicated that laser with a 650-nm wavelength reduced the
up, and pain. For older veterinary patients suffering from cancer severity of OM and pain scores. 114 No adverse effects were noted
and those recovering from surgery and experiencing postoperative in this study. In 2011 a systematic review of studies on this topic
ileus, regulation of digestive function through massage may pro- concluded that although sample sizes were low, overall data were
vide much-needed parasympathetic support. consistently in favor of LLLT both preventing and diminishing
The relaxing benefits of medical massage assist veterinary the severity of OM in patients receiving chemotherapy or RT. 115
oncology patients in counteracting stress during minimally inva- PBM for the prevention of oral mucositis not only lowers morbid-
sive procedures, although it should never be relied on to replace ity; it also may save thousands of dollars per case prevented. 116
conventional anesthesia and analgesia for more painful events. Human patients with advanced head and neck cancer experi-
Facial massage calms patients at least in part by activating trigem- ence many complications after receiving RT or chemoradiother-
inal-vagal reflexes. 111 Veterinary technicians can include certain apy. These interventions may cause loss of function and negatively
techniques while assisting with gentle restraint; slow, up-and- affect quality of life. In the acute phase, complications include
down moderate pressure massage along the midline between the OM, pain, dysphagia, dysgeusia, dermatitis, changes in salivary
nose and forehead can sometimes induce a quasihypnotic state. function, and infection. Over time, patients may develop neurop-
athies, tooth demineralization and caries, periodontitis, soft tissue
What Are the Risks of Massage for Cancer Patients? and/or bone necrosis, mucocutaneous and muscular fibrosis, tris-
Patients with osteosarcoma, skeletal metastasis, spinal instabil- mus, lymphedema, and voice or speech changes. 116 Biologically,
ity, low platelet count, or osteopenia should avoid deep massage. PBM has the potential to control pain, improve tissue health,
Light or moderate pressure, delivered through skilled hands after maintain organ function and prevent or mitigate these complica-
informed palpation, would not be contraindicated, except over tions. PBM has demonstrated the ability to enhance wound repair
painful regions or areas that have undergone recent surgery, dem- and tissue regeneration as it proceeds from the inflammatory, to
onstrate instability, or harbor infection. Massage should be avoided the proliferative, and finally to the remodeling phases of injury res-
over implantations to deliver chemotherapy or other drugs. Mas- olution, resulting in significantly less inflammation and fibrosis. 117
sage to sites containing stents or prostheses may cause displace-
ment. Tissues subjected to prior surgery or RT may be fragile, and How Might Laser Therapy Harm Cancer Patients?
massage to these areas should either be avoided or be done gently. Little in vivo research is currently available pertaining to the risk
Hypercoagulable patients may experience emboli subsequent to of LT stimulating cancer growth. However, prudent practice war-
deep pressure over a thrombus; patients who are prone to bleeding rants avoiding LT in cancer patients or at least, tumor sites. Ques-
may develop hematomas secondary to pressures that in normal tions remain about the safe distance from a tumor at which one
patients would not cause problems. Deep abdominal massage has can deliver light therapy and appropriate and nonproliferative
caused internal bleeding even in the absence of bleeding disorders. wavelengths and doses of light. Until more is known about the
Although no evidence exists to indicate that massage promotes the specific effects of PBM on tumors and circulating lymphocytes, LT
likelihood of tumor metastasis, one should avoid massage directly may be considered contraindicated for patients with lymphoma.
over known tumors or predictable metastasis sites.
Conclusion
Photobiomodulation (Laser Therapy)
Cancer patients face a multiplicity of challenges, as both the
Photobiomodulation (PBM), formerly known as low-level laser treatment and the disease can make them miserable. Fortunately,
therapy (LLLT) or simply laser therapy (LT), involves exposing medical research is revealing ways in which integrative options can
tissues to photons from laser units or light-emitting diodes (LEDs) lessen cancer patients’ suffering and even improve survivorship. 118