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Back to the roots: traditional medicine for cancer control in Latin America and the Caribbean
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WHO
estimates that 65% of the world's population uses traditional medicine
alone or in combination with modern medicine. Thus, in Latin America at
least 390 million people, including 50–60 million indigenous people who
have access only to traditional medicines and medicinal plants, use
traditional medicines for various health problems, including cancer. The
number of Latin Americans who use traditional medicines could be higher
than world averages because of the migration of people with indigenous
backgrounds to large modern cities, where shops of medicinal plants and
traditional healers are often located near modern hospitals.
Acceptance
of traditional medicine is based on the widespread perception of the
safety of medicinal plants, but wide dissemination and accessibility
also have roles. For example, the graviola (the fruit of Annona muricata), also called the soursop or Brazilian paw paw, and known in Spanish as guanabana,
can be bought in any local market in South America, is credited with
anti-inflammatory and antihyperglycaemic properties, and has shown
efficacy against cancer in preclinical settings.1, 2, 3 The bark of Uncaria tomentosa,
or cat's claw, an Amazon vine with antiproliferative activity, is often
used as a complement to chemotherapy, even by western doctors.4, 5
The
search for medicinal plants with potential antitumour activity by the
US National Cancer Institute was intense from 1960 to 1980,6 even in Latin America.7, 8
However, there is another less obvious aspect of traditional medicine's
role in cancer control in Latin America—namely, the possibility that
the traditional medical system itself contributes to control.
In The Lancet Oncology Commission, Paul Goss and colleauges9
show the limited access to cancer services in much of Latin America and
the Caribbean, but in these places traditional medicine is available,
with practitioners such as indigenous healers who have therapeutic
arsenals, whom people can attend when modern health services fail. The
acceptability of traditional medicine in the general population should
lead to consideration of intercultural approaches to these diverse
systems, which, when combined with modern medicine, could provide an
alternative first line of diagnosis to conventional cancer services.
Culturally appropriate services in Bolivia, Ecuador, Guatemala, and
Peru, among other countries, have shown the wide acceptance and the
possibility of coexistence and collaboration between traditional and
modern medicines.10
Try
to imagine a future in which traditional medicine is not only a source
of therapeutic drugs for cancer control, but also a mechanism for cancer
prevention. Focus on the tens of millions of Latin Americans who have
access only to traditional medicine. We need to develop policies that
allow for the recognition of traditional healers, recover and preserve
their knowledge, and lead efforts in research, not only to find new
resources, but also to incorporate traditional medicine and its
practitioners into modern medicine.
I declare that I have no conflicts of interest.
References
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