Patients with advanced breast cancer that has spread to the skin are likely to cause more harm than good if they use complementary therapies to treat their skin lesions.
Professor Maria João Cardoso, head breast surgeon at the Champalimaud Cancer Centre and a teacher at the Nova Medical School in Lisbon, Portugal, told the Advanced Breast Cancer Fifth International Consensus Conference (ABC5) in Lisbon today (Thursday) that there was a long list of herbal products and creams that patients often try, but many of them could delay wound healing and interfere with systemic anti-cancer treatments such as hormone therapy or chemotherapy.
"It's very important that patients always check with their doctors first before trying complementary treatments for cancer that has spread to the skin," she said. "Many patients do not check and do not tell their doctors that they are using complementary therapies.
"There are many of these therapies, especially herbal products and topical creams, that can have a negative impact in cancer treatment. Many compounds are complex and some ingredients can delay healing and interfere with the efficacy of ongoing systemic treatments. Laboratory studies have shown that certain products can reduce the blood clotting process required for a wound to heal. If a patient has a bleeding wound, these compounds can have a strong, adverse impact on scarring and how well wound dressings work."
Complementary compounds that adversely affect clotting include: green chiretta (Andrographis paniculata), feverfew (Tanacetum parthenium), garlic (Allium sativum), ginger (Zingiber officinalis), ginkgo (Ginkgo biloba), ginseng (Panax ginseng), hawthorn (Crataegus spp.), horse chestnut (Aesculus hippocastanum) and turmeric (Curcuma longa).
"These are just some examples. The number of herbal products available is huge and the available evidence for their efficacy is nil," said Prof Cardoso.
Approximately 5% of solid tumours (excluding skin cancer) can spread (metastasise) to the skin, and breast cancer is the cancer that is most likely to do so, occurring in as many as 20% of cases. In addition, inoperable, locally advanced breast cancer (cancer that has spread to the skin, chest wall and some lymph nodes), and cancer recurrences in the same area can result in clusters of cancer cells in the skin.
Prof Cardoso said: "Skin lesions often cause discomfort and distress and they are very difficult to treat successfully. Topical treatments that can be applied directly to the lesion, have become more popular, although they are successful in healing or controlling the wound in no more than 50% of cases.
"Although doctors' primary concern is to understand the biology, extent and history of the disease in their patients, the curse of the visible and disfiguring lesions, the pain, the smell and all the psychologic impact on the patients and their loved ones must not be underestimated. In these circumstances it's not surprising that patients and their carers search for complementary or alternative treatments that might make a difference. But they could end up doing more harm than good."
On the other hand, Prof Cardoso said that complementary therapies that aim to alleviate the psychological distress caused by having unsightly skin metastases have no contra-indications and can have a positive impact on patients' quality of life.
"These include using mindfulness to reduce stress, acupuncture, Reiki and yoga," she said.
"The outcome of conventional medical treatment, particularly in the most difficult cases, such as visible cancer, depends on the efficacy of available treatments, the commitment of multidisciplinary teams and the involvement and education of patients about the 'dos and don'ts'. The highest goal in medicine is important to remember—do no harm," she concluded.
Provided by European School of Oncology