No studies in the published peer-reviewed literature discuss aromatherapy as a treatment for cancer specifically. The studies discussed below, most of which were conducted in patients with cancer, primarily focus on other health-related conditions and on quality-of-life measures such as stress and anxiety levels.
A major review published in 2000  focused on six studies investigating treatment or prevention of anxiety with aromatherapy massage. Although the studies suggested that aromatherapy massage had a mild transient anxiolytic effect, the authors concluded that the research done at that time was not sufficiently rigorous or consistent to prove the effectiveness of aromatherapy in treating anxiety. This review excluded trials related to other effects of aromatherapy (such as pain control) and did not include any studies looking at the effects of odors that were not specifically labeled as aromatherapy.
Several of the studies included in the Cochrane Database of Systematic Reviews are discussed in more detail. A randomized controlled pilot study examined the effects of adjunctive aromatherapy massage on mood, quality of life, and physical symptoms in patients with cancer. Forty-six patients were randomly assigned to conventional day care alone or day care plus weekly aromatherapy massage using a standardized blend of oils (1% lavender and chamomile in sweet almond carrier oil) for 4 weeks. Patients self-rated their mood, quality of life, and the intensity of the two symptoms that were the most concerning to them at the beginning of the study and at weekly intervals thereafter. Of the 46 patients, only 11 of 23 (48%) in the aromatherapy group and 18 of 23 (78%) in the control group completed all of the 4 weeks. Patient-reported mood, symptoms, and quality of life improved in both groups, and there was no statistically significant difference between the two groups in any of these measures.
Another randomized controlled trial examined the effects of aromatherapy massage and massage alone on 42 patients with advanced cancer over a 4-week period. Patients were randomly assigned to receive weekly massages with or without aromatherapy; the treatment group (aromatherapy group) received massages with lavender essential oil (Lavandula angustifolia Miller [synonyms: Lavandula spicata L.; Lavandula vera DC.]) and an inert carrier oil, and the control group (massage group) received either an inert carrier oil alone or no intervention. The authors reported no significant long-term benefits of aromatherapy or massage in pain control, quality of life, or anxiety, but sleep scores (as measured by the Verran and Snyder-Halpern sleep scale) improved significantly in both groups. The authors also reported statistically significant reductions in depression scores (as measured by the Hospital Anxiety and Depression Scale [HADS]) in the massage-only group.
A placebo-controlled, double-blind, randomized trial conducted in Australia investigated the effects of inhalation aromatherapy on anxiety during radiation therapy. A total of 313 patients receiving radiation therapy were randomly assigned to one of three groups: carrier oil with fractionated oils, carrier oil only, or pure essential oils of lavender, bergamot (Citrus aurantium L. ssp. bergamia [Risso] Wright & Arn. [Rutaceae]; [synonym: Citrus bergamia Risso]), and cedarwood (Cedrus atlantica [Endl.] Manetti ex Carriere [Pinaceae]). All three groups received the oils by inhalation during their radiation therapy. The authors reported no significant differences in depression (as measured by HADS) or psychological effects (as measured by the Somatic and Psychological Health Report) between the groups. The group that received only the carrier oil showed a statistically significant decrease in anxiety (as measured by HADS) compared with the other two groups.
Another randomized controlled trial investigated the effects of massage or aromatherapy massage in 103 cancer patients who were randomly assigned to receive massage using a carrier oil (massage group) or massage using a carrier oil plus the Roman chamomile essential oil (Chamaemelum nobile [L.] All. [synonym: Anthemis nobilis L.]) (aromatherapy massage group). Two weeks after the massage, the authors found a statistically significant reduction in anxiety in the aromatherapy massage group (as measured by the State-Trait Anxiety Inventory) and an improvement in symptoms (as measured by the Rotterdam Symptom Checklist [RSCL]; the subscales with improved scores were psychological, quality of life, severe physical, and severe psychological). The authors reported that the massage-only group showed improvement on four RSCL subscales; however, these improvements did not reach statistical significance.
In a placebo-controlled, double-blind, randomized trial of bergamot inhalation aromatherapy compared with a pleasant smelling shampoo that did not contain essential oils, administered at the time of stem cell infusion in 37 children and adolescents undergoing stem cell transplant, aromatherapy was not found to be beneficial in reducing nausea, anxiety, or pain. As administered in this study, bergamot inhalation aromatherapy may have contributed to persistent anxiety following the infusion of stem cells. Although no more effective than placebo, parents receiving aromatherapy showed a significant decrease in their transitory anxiety during the period between the completion of their child’s infusion and 1 hour following infusion. Nausea and pain subsided over the course of the intervention for all children, though nausea remained significantly greater in patients receiving aromatherapy. These findings suggest that the diffusion of bergamot essential oil may not provide suitable anxiolytic and antiemetic effects among children and adolescents undergoing stem cell transplantation. The double blinding of the trial may explain the results, as single-blinded or nonblinded trials in general supported the aromatherapy intervention.
A similar study evaluated the efficacy of an aromatherapy intervention for reduction of symptom intensity of nausea, retching, and/or coughing among adult patients receiving stem cells preserved in dimethyl sulfoxide. The study found that an intervention of tasting or sniffing sliced oranges was more effective at reducing symptom intensity than an orange essential oil inhalation aromatherapy.
A study whose primary objective was evaluating an aromatherapy service following changes made after an initial pilot at a U.K. cancer center also reported on the experiences of patients referred to the service. Of 89 patients originally referred, 58 completed six aromatherapy sessions. The authors reported significant improvements in anxiety and depression (as measured by HADS) at the completion of the six sessions, as compared with before the six sessions. A small study examined the physical and psychological effects of aromatherapy massage in eight patients with primary malignant brain tumors attending their first follow-up appointment after radiation therapy. The author reported no psychological benefit in these patients from aromatherapy massage (as measured by HADS) but reported a statistically significant reduction in blood pressure, pulse, and respiratory rate.
Antibiotic -resistant bacteria, such as methicillin-resistant Staphylococcus aureus (MRSA) and vancomycin -resistant enterococcus, are an increasing problem worldwide, causing intractable wound infections. Mixtures, such as those containing the volatile oils of lemongrass, eucalyptus, melaleuca, clove, and thyme with butylated hydroxytoluene, triclosan (0.3%), and 95% undenatured ethanol (69.7%), are being investigated against MRSA in vitro . No clinical trials have been performed.
Two topical MRSA eradication regimens were compared in hospital patients. A standard treatment, which included mupirocin 2% nasal ointment, chlorhexidine gluconate 4% soap, and silver sulfadiazine 1% cream was given versus a tea tree oil regimen (melaleuca), which included tea tree 10% cream and tea tree 5% body wash. Both were administered for 5 days. One hundred fourteen patients received the standard treatment, and 56 (49%) were cleared of MRSA carriage. One hundred ten patients received the tea tree oil regimen, and 46 (41%) were cleared of MRSA carriage. In a small group of patients, the tea tree oil regimen was associated with a higher clearance rate of MRSA carriage in the axilla, groin, and wound sites, but the difference versus standard treatment was not significant.
Current Clinical Trials
Check NCI’s list of cancer clinical trials for cancer CAM clinical trials on aromatherapy and essential oils that are actively enrolling patients.
General information about clinical trials is also available from the NCI Web site.
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- Sherry E, Boeck H, Warnke PH: Percutaneous treatment of chronic MRSA osteomyelitis with a novel plant-derived antiseptic. BMC Surg 1: 1, 2001. [PUBMED Abstract]
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