Key words
cancer - gynecologic oncology - herbal medicine - integrative medicine - complementary
and alternative medicine
Schlüsselwörter
Krebs - gynäkologische Onkologie - pflanzliche Arzneimittel - integrative Medizin
- alternative und komplementäre Medizin
Introduction
More and more information is becoming available about the use of complementary and
alternative medicine (CAM) or integrative medicine by patients with cancer. Surveys
of patients with gynecologic cancer have shown that approximately 40 – 50% of patients
use some form of CAM [1], [2], [3], [4]. The majority of CAM remedies, such as vitamins, herbal medicine, or plant extracts,
are taken orally [2], [3]. Herbal medicines and herbal supplements are among the most popular CAM products.
A systematic literature review on the use of herbal supplements in the United Kingdom
reported that up to 22% of cancer patients were taking herbal supplements [5].
Reasons given by patients for using CAM, including herbal medicines, included treatment
of cancer-related symptoms and improvement of quality of life [6].
Herbal medicine is an integral part of Western traditional medicine. According to
the definition of the World Health Organization (WHO), herbal medicines include types
of medicine that use herbs or herbal materials, herbal preparations, and finished
herbal products containing parts of plants or materials made from plants as the active
ingredient [7]. In Germany, certain forms of traditional herbal medicine such as homeopathy and
anthroposophic medicine are considered to be part of the specialized therapy options
described in the German Medicines Act and have been granted special approval status
[8]. Recent estimates about the drug market in Germany show that herbal medicines represent
approximately 30% of over-the-counter medications [9].
However, the use of herbal medicine varies widely across Europe. A single medicinal
plant may be regarded as an herbal medicine, food, functional food, or dietary supplement
in different countries, depending on each countryʼs national regulations on different
medicines [5]. Although strict rules on the quality and quantity of the ingredients of herbal
medicines and their labeling apply to herbal medicines, the same does not apply to
food products and dietary supplements, making the market for herbal products extremely
diverse. To obtain authorization from the relevant national drug authority to market
a product as a medicinal product, herbal medicines and herbal medicinal products require
a full quality dossier, as well as evidence of efficacy and safety, either based on
clinical trials or from scientific literature or bibliographic data [10], [11], [12]. Dietary supplements and food products, on the other hand, are not the responsibility
of drug approval authorities, so that there are no rules regarding evidence of their
quality, efficacy, and safety. Dietary and food supplements involve concentrated nutrients
or other substances with a nutritional or physiological effect that are sold in “doses”,
i.e., in the form of tablets or capsules, and are regulated as foodstuffs [13]. Unfortunately, it is not always obvious if an herbal product is being marketed
as food or as a medicinal product. For example, peppermint leaves used to prepare
an herbal infusion can be marketed as a foodstuff or as an herbal medicine. To the
best of the authorsʼ knowledge, there is no definition of an herbal product that is
independent of its purpose as a medicinal product or food. The heterogeneity among
herbal products increases the difficulty for healthcare professionals when counseling
patients, as well
as the difficulty patients have when choosing a safe but also potent herbal medicine.
Phytotherapy, or treatment with herbal medicine, includes the use of potent plants
that may cause side effects or interact with drugs [14], [15]. Caution is needed, particularly when herbal products are used to treat side effects
associated with cancer therapy, as herbal medicines may interact with the chemotherapeutic
agents, for example, by increasing the toxicity or reducing the effectiveness of the
cancer therapy. Novel therapy approaches available to treat gynecologic cancers, for
example, poly(adenosine diphosphate ribose) polymerase (PARP) inhibitors, may be affected
by interactions caused by cytochrome P450 (CYP) enzymes [16], [17]. Some recommendations therefore go as far as discouraging the use of herbal supplements
altogether [18]. In addition, patients often do not disclose their use of CAM and herbal
medicines to the physicians treating them [4], [19], [20], [21], [22], [23], [24].
In order to provide optimal therapy to patients with gynecologic cancer and also take
their personal wish to use CAM and herbal medicine into account, it is important to
know which herbal medicines are used by patients with gynecologic cancer and whether
there are any differences in the use of herbal medicine by gynecologic carcinoma patients
and by heathy persons.
Methods
Description of study
The study was approved by the local ethics committee (reference number 255_16 B) and
the study protocol complied with the Declaration of Helsinki. All of the participants
provided written informed consent. This retrospective cross-sectional study was conducted
at the Department of Gynecology and Obstetrics of Erlangen University Hospital.
Between December 2016 and January 2017, a standardized questionnaire on the use of
herbal products was developed and validated in a group of 29 patients receiving follow-up
care after breast cancer and five patients from the hospitalʼs integrative medicine
consultancy service (see questionnaire in the Supporting Information 1). These patients
received the original questionnaire and were asked to evaluate it on a separate evaluation
sheet which included items on “comprehensibility,” “complexity,” “time required for
completion,” and whether the patients “felt comfortable answering the questionnaire”
or had any suggested improvements. Minor revisions to the questionnaire were adopted
after the validation phase and before the questionnaire was used for the final survey.
The cross-sectional survey took place between March 2017 and December 2018. The questionnaire
was administered to female patients with breast cancer or gynecologic cancer, and
to healthy women attending appointments for preventive medical check-ups. A total
of 868 questionnaires were returned. Four questionnaires had to be excluded, as they
had been answered by the same patient. To be eligible for inclusion in the analysis,
participants had to have a diagnosis of gynecologic carcinoma or be a healthy woman
attending a check-up. A total of 413 data sets were available for analysis. Data of
breast cancer patients were not included in this evaluation but will be provided in
a separate analysis.
The participantsʼ clinical records were used to collect information on patient and
tumor characteristics. All of the participants completed the validated questionnaire
on the use of plant products. The questionnaire comprised one general question on
the plants used by the participants and included five items with questions on the
type of use, duration of use, reasons for use, as well as information on the medical
use of specific plant products (Supporting Information 1). For the purposes of the
questionnaire, a plant product or herbal product was defined as any processed product
derived from plants, irrespective of its regulatory status. Both herbal medicines
and food products or dietary supplements were included.
Statistical considerations
Statistical evaluation was performed using descriptive statistics and included calculations
of absolute numbers, percentages, means, and standard deviations. The group of patients
with gynecologic cancer was compared with the group of healthy controls. Analysis
of variance (ANOVA) was used to assess age differences between the groups. A logistic
regression model adjusted for age was used to assess differences in plant use between
the groups. Risk ratios for numbers of plants used and sources of recommendations
were assessed using a Poisson regression model. A p value of 0.05 was set as the threshold
for significance. All calculations were carried out using the statistics program IBM
SPSS, version 21 (IBM Corporation, Armonk, New York, USA). Missing data were excluded
from the analysis.
Results
Characteristics of participants
A total of 413 participants were included in the analysis: 201 in the group with gynecologic
carcinomas and 212 in the group of healthy controls. The mean age was 57.2 (± 13.9)
years in the group of cancer patients and 49.4 (± 13.5) years in the group of healthy
controls. The healthy participants were significantly younger than the cancer patients.
The majority of cancer patients had ovarian cancer (43%) or were in a post-treatment
setting (45%). At the time of completing the survey, 20 patients (25%) were receiving
chemotherapy, 26 patients (13%) were receiving targeted therapy, and 139 patients
(69%) were not receiving systemic therapy. [Table 1] lists the participantsʼ characteristics.
Table 1 Characteristics of patients and healthy controls.
|
|
Gynecologic cancer patients (n = 201)
|
Healthy controls (n = 212)
|
p
|
|
* Multiple responses allowed. # ANOVA. SD: standard deviation.
|
|
Age (mean ± SD, years)
|
57.2 ± 13.9
|
49.4 ± 13.5
|
< 0.001#
|
|
Tumor location*
|
|
|
|
|
|
86 (43%)
|
|
|
|
|
33 (16%)
|
|
|
|
|
46 (23%)
|
|
|
|
|
21 (10%)
|
|
|
|
|
19 (10%)
|
|
|
|
Disease stage
|
|
|
|
|
|
153 (76%)
|
|
|
|
|
8 (4%)
|
|
|
|
|
40 (20%)
|
|
|
|
Therapy stage
|
|
|
|
|
|
22 (11%)
|
|
|
|
|
41 (20%)
|
|
|
|
|
48 (24%)
|
|
|
|
|
90 (45%)
|
|
|
|
Current therapy*
|
|
|
|
|
|
50 (25%)
|
|
|
|
|
3 (2%)
|
|
|
|
|
26 (13%)
|
|
|
|
|
6 (3%)
|
|
|
|
|
139 (69%)
|
|
|
Use of plant products
There were 138 users of plant products (69%) among the patients with gynecologic cancer.
By comparison, more healthy participants used plant products (n = 172, 81%). The difference
was statistically significant. The plants most commonly used by both groups were ginger,
peppermint, green tea, chamomile, fennel, sage, stinging nettle, arnica, caraway,
and olive. The healthy participants used sage (p = 0.003), caraway (p = 0.002), and
olive (p = 0.004) more often. In comparison with the healthy controls, patients with
gynecologic cancer used fewer plant products (RR = 0.79; 95% CI 0.70 – 0.89). No specific
plant was used more often by patients with gynecologic cancer compared with healthy
participants. [Table 2] provides a summary of the plants used by healthy controls and cancer patients.
Table 2 General use of plants by patients with gynecologic cancer and healthy controls.
|
|
Gynecologic cancer patients (n = 201)
|
Healthy controls (n = 212)
|
p*
|
|
* Logistic regression model adjusted for age.
Multiple responses were allowed.
bold: p < 0.05
|
|
Individuals using plant products (n, %)
|
138 (69%)
|
172 (81%)
|
0.011
|
|
Plants used (n, %)
|
|
|
|
|
|
57 (28%)
|
92 (43%)
|
0.088
|
|
|
59 (29%)
|
82 (39%)
|
0.144
|
|
|
37 (18%)
|
60 (28%)
|
0.271
|
|
|
39 (19%)
|
62 (29%)
|
0.092
|
|
|
34 (17%)
|
53 (25%)
|
0.177
|
|
|
24 (12%)
|
55 (26%)
|
0.003
|
|
|
26 (13%)
|
37 (17%)
|
0.687
|
|
|
21 (10%)
|
31 (15%)
|
0.908
|
|
|
16 (8%)
|
33 (16%)
|
0.020
|
|
|
13 (6%)
|
37 (17%)
|
0.004
|
The mean number of plant products used by cancer patients was 3.3 (± 2.7), compared
to 4.1 (± 3.1) used by healthy participants. While 70% (n = 319) of the plants were
used over a longer period of time (more than 8 weeks) by oncologic patients, 55% (n = 387)
of the plants were used for more than 8 weeks by healthy participants. The number
of plants used for a short period (less than 8 weeks) was 117 (26%) for patients with
gynecologic cancer and 293 (41%) for healthy participants. Although there were no
significant differences between the two groups with regard to the long-term use of
plant products (RR = 0.97; 95% CI 0.83 – 1.13), more healthy participants used plant
products for short periods (RR = 0.43; 95% CI 0.35 – 0.54).
Use of plant products for medicinal purposes
The number of healthy participants who used plants for medicinal purposes was significantly
higher compared to patients with gynecologic cancer. While 56% of the healthy participants
(n = 119) stated that they used plants for medicinal purposes, only 40% of patients
with gynecologic cancer (n = 81) did so (p = 0.027). The plants used most often for
medicinal purposes were arnica, ginger, sage, chamomile, fennel, peppermint, valerian,
stinging nettle, caraway, and calendula. No statistically significant differences
were observed between the groups with regard to individual plants, with the exception
of fennel (p = 0.021) and peppermint (p = 0.014), which were used more often by healthy
participants. Patients with gynecologic cancer used fewer plant products for medicinal
purposes than healthy participants (RR = 0.71; 95% CI 0.58 – 0.85). [Table 3] lists the plants used for medicinal purposes.
Table 3 Use of plants for medicinal purposes by patients with gynecologic cancer and healthy
controls.
|
|
Gynecologic cancer patients (n = 201)
|
Healthy controls (n = 212)
|
p*
|
|
* Logistic regression model adjusted for age.
Multiple responses were allowed.
bold: p < 0.05
|
|
Individuals using plant products (n, %)
|
81 (40%)
|
119 (56%)
|
0.027
|
|
Plants used (n, %)
|
|
|
|
|
|
20 (10%)
|
31 (15%)
|
0.998
|
|
|
11 (5%)
|
31 (15%)
|
0.075
|
|
|
8 (4%)
|
35 (17%)
|
0.745
|
|
|
13 (6%)
|
32 (15%)
|
0.095
|
|
|
9 (5%)
|
27 (13%)
|
0.021
|
|
|
7 (3%)
|
27 (13%)
|
0.014
|
|
|
11 (5%)
|
16 (8%)
|
0.999
|
|
|
11 (5%)
|
20 (9%)
|
0.528
|
|
|
7 (3%)
|
18 (8%)
|
0.412
|
|
|
9 (5%)
|
15 (7%)
|
0.725
|
The most common symptoms treated with plant products are listed in [Table 4]. Respiratory complaints and common colds were the symptoms reported most often by
healthy participants (n = 58, 49%), followed by gastrointestinal complaints (n = 31,
26%), and anxiety or trouble sleeping (n = 26, 22%). The most common symptoms reported
by cancer patients were gastrointestinal complaints (n = 14, 17%), anxiety or trouble
sleeping (n = 13, 16%), as well as cancer, impaired immune system, and respiratory
complaints/common cold (each n = 10, 12%).
Table 4 Top 15 symptoms treated with plant products by patients with gynecologic cancer and
healthy controls.
|
|
Gynecologic cancer patients (n = 81)
|
Healthy controls (n = 119)
|
p*
|
|
Only users of plant products for medicinal purposes were included in the analysis.
Multiple responses were allowed. * Logistic regression model adjusted for age.
bold: p < 0.05
|
|
Respiratory complaints and common cold
|
10 (12%)
|
58 (49%)
|
< 0.001
|
|
Gastrointestinal complaints
|
14 (17%)
|
31 (26%)
|
0.169
|
|
Anxiety/trouble sleeping
|
13 (16%)
|
26 (22%)
|
0.061
|
|
Cancer
|
10 (12%)
|
1 (1%)
|
0.011
|
|
Impaired immune system
|
10 (12%)
|
4 (3%)
|
0.026
|
|
Impaired wound healing
|
9 (11%)
|
13 (11%)
|
0.946
|
|
Musculoskeletal complaints
|
5 (6%)
|
17 (14%)
|
0.089
|
|
Dry skin
|
4 (5%)
|
6 (5%)
|
0.765
|
|
Swelling/edema
|
6 (7%)
|
8 (7%)
|
0.539
|
|
Flatulence
|
5 (6%)
|
5 (4%)
|
0.975
|
|
Hepatobiliary complaints
|
2 (2%)
|
2 (2%)
|
0.625
|
|
Nausea
|
3 (4%)
|
7 (6%)
|
0.452
|
|
Menopausal complaints/
hot flashes
|
2 (2%)
|
2 (2%)
|
0.770
|
|
Urinary tract complaints
|
4 (5%)
|
3 (3%)
|
0.404
|
|
Improvement of general condition
|
2 (2%)
|
2 (2%)
|
0.923
|
Sources of recommendations for plant products
The numbers of plant products recommended for medicinal purposes by physicians, pharmacists,
alternative practitioners, family and friends, internet/newspapers, or other sources
are listed in [Table 5]. Participants mainly received their information about herbal medicine from family
and friends. No statistically significant differences between the two groups were
observed with regard to the number of plants recommended by other sources of information.
Table 5 Sources of recommendations of medicinal plant products to patients with gynecologic
cancer and healthy controls.
|
|
Gynecologic cancer patients
n (%)
|
Healthy controls
n (%)
|
|
Multiple responses allowed. Only individuals using medicinal plant products were included
in the analysis.
|
|
Total medicinal plant products
|
171
|
357
|
|
Physician
|
41 (24%)
|
108 (30%)
|
|
Pharmacist
|
23 (13%)
|
21 (6%)
|
|
Alternative practitioner
|
23 (13%)
|
60 (17%)
|
|
Family/friends
|
80 (47%)
|
191 (54%)
|
|
Internet/newspapers
|
37 (22%)
|
83 (23%)
|
|
Other
|
23 (13%)
|
58 (16%)
|
Discussion
Although herbal medicine is one of the most popular types of CAM used by patients
with gynecologic cancer with a prevalence of up to 23%, little is known about the
actual herbal products or plants used by these patients [2]. To the best of the authorsʼ knowledge, this is the first study that has focused
exclusively on patients with gynecologic cancer and their use of herbal products or
herbal medicines.
The study showed that cancer patients use herbal medicine less frequently than healthy
persons. The use of herbal products specifically for medicinal purposes is more common
among healthy individuals. However, patients with gynecologic cancer usually use herbal
medicinal products for a longer period (> 8 weeks). The major source of information
about herbal medicines in both groups was family and friends.
The present study consisted of a large group with a total of 413 participants, of
whom 201 were patients with gynecologic cancers. In Germany, the annual incidence
of gynecologic cancers is around 26 000, which amounts to around 10% of all cancer
diagnoses [25]. Carcinomas of the uterus are the most common type of gynecologic cancer in Germany
[26], [27], [28]. However, the majority of cancer patients in our study had ovarian cancer. Earlier
studies have shown that patients with ovarian cancer are particularly likely to use
CAM, including herbal medicine [2]. A possible explanation is that the use of herbal medicine may be associated with
the use of systemic treatment. In addition to surgery, patients with ovarian cancer
often also receive systemic treatments such as chemotherapy or novel therapies such
as treatment
with PARP inhibitors [17], [29], which are prone to have side effects. Treatment for the side effects of cancer
therapy is one of the most common reasons for using CAM, including herbal medicine
[1], [2].
The mean age of the cancer patients included in this survey was 57 years, 10 years
older than the group of healthy participants. Although gynecologic cancers such as
ovarian cancer may occur in patients younger than 45, the probability of developing
cancer generally increases with age [30].
The survey investigated the use of plant products in patients with gynecologic cancers
and compared it with that of controls. For the purposes of this study, a plant product
was considered to be any product containing a plant as a major ingredient, regardless
of its regulatory status, e.g., food products, dietary supplements or herbal medicines,
and irrespective of the number of plants contained in the product. To the best of
the authorsʼ knowledge, there is no standardized definition of an herbal product.
The definition depends on the regulatory context which determines how the product
may be sold. In Germany, there are different ways in which herbal products are used,
for example as a foodstuff, an herbal medicine or as part of a dietary supplement.
While herbal medicines must comply with different quality standards and safety parameters,
this level of control is not required for foodstuffs. The EMA defines an herbal medicinal
product as “any medicinal product,
exclusively containing as active ingredients one or more herbal substances, one
or more herbal preparations, or a combination of the two” and an herbal substance
as “all mainly whole, fragmented or cut plants, plant parts, algae, fungi, lichen
in an unprocessed, usually dried, form, but sometimes fresh. Certain exudates that
have not been subjected to a specific treatment are also considered to be herbal substances”,
while herbal preparations are “preparations obtained by subjecting herbal substances
to treatments such as extraction, distillation, expression, fractionation, purification,
concentration or fermentation. These include comminuted or powdered herbal substances,
tinctures, extracts, essential oils, expressed juices and processed exudates” [31]. When evaluated in the context of food, botanicals are defined as “all botanical
materials (e.g. whole, fragmented or cut plants, plant parts, algae, fungi and lichens)”
and botanical
preparations are “all preparations obtained from botanicals by various processes
(e.g. pressing, squeezing, extraction, fractionation, distillation, concentration,
drying up and fermentation).” [32] Which of these definitions applies, depends on the purpose for which these herbal
products are sold. However, this differentiation may not always be clear to the consumer
of the product. The WHO provides a definition for a finished herbal product as follows:
“Finished herbal products consist of one or more herbal preparations made from one
or more herbs (i.e. from different herbal preparations made of the same plant as well
as herbal preparations from different plants. Products containing different plant
materials are called ”mixture herbal products“). Finished herbal products and mixture
herbal products may contain excipients in addition to the active ingredients. However,
finished products or mixture herbal products to which chemically defined
active substances have been added, including synthetic compounds and/or isolated
constituents from herbal materials, are not considered to be ”herbal“.” [33]. The WHO document also states that “Herbal preparations are the basis for finished
herbal products and may include comminuted or powdered herbal materials, or extracts,
tinctures and fatty oils of herbal materials. They are produced by extraction, fractionation,
purification, concentration or other physical or biological processes. They also include
preparations made by steeping or heating herbal materials in alcoholic beverages and/or
honey, or in other materials.” [33]. The subjects in our study were expected to complete the questionnaire themselves
without assistance. Therefore, we cannot assume that our study subjects were familiar
with the correct definition of an herbal product, which depends on its regulatory
context. Hence, we opted for a more
feasible and less complex definition and summarized all plant-derived products
as herbal products.
Use of herbal products was high in both groups. A review focusing on herbal medicine
use among adult cancer patients in the United Kingdom estimated that between 3.1%
and 21.8% of the patients used phytotherapy [5]. The figure in the present study was considerably higher. Even when only evaluating
the use of plant products for medicinal purposes, 40% of cancer patients reported
using herbal medicines. CAM use, including the use of herbal medicines, is often associated
with female cancer patients, younger age, and higher socioeconomic status [34], [35], [36].
Herbal products are generally considered to be safe, and the level of acceptance for
them in the general population is high. However, healthy participants in this study
used plant products considerably more often than patients with gynecologic cancer.
Possible reasons for this may be that cancer patients are cautious about self-medication
and fear potential drug interactions and side effects [37]. Cancer patients may also have already received several other medications and therefore
did not wish to take any more pills. Many doctors also discourage the use of herbal
medicines due to a fear of interaction with drug therapy [15].
Apart from sage, caraway, and olive, there were no differences between the two groups
with regard to the use of specific medicinal plants. Healthy participants used these
products more often than cancer patients. The plants were commonly used as food products,
as spices or herbal infusions, and are characterized by their distinctive aromatic
smell and taste. Similar findings were observed for the use of plants for medicinal
purposes. Healthy participants used peppermint and fennel, both easily identified
by their characteristic smell and taste, significantly more often than patients with
gynecologic cancer. Patients receiving chemotherapy often have gastrointestinal symptoms
with disruption of the mucosal membranes and become sensitive to tastes and smells
[35]. These patients may therefore avoid using strong-tasting or strong-smelling plant
products such as sage, caraway, fennel, or peppermint.
The plants most commonly used for medicinal purposes were arnica, ginger, sage, and
chamomile, which are common remedies for general complaints such as wounds, gastrointestinal
symptoms, respiratory symptoms, and inflammations [38], [39].
This is consistent with the symptoms reported by the survey participants for which
they used herbal medicines. The most common symptoms treated with herbal remedies
were respiratory complaints or common cold, gastrointestinal complaints, and anxiety.
All of these symptoms are regular indications for treatment with over-the-counter
medicines [39], [40]. Generally, there were few differences in the indications for using herbal medicines
between the two groups. However, some of the reasons given for the medicinal use of
plant products differed between the groups. Whereas healthy participants turned to
herbal medicine to treat general symptoms/general conditions, cancer patientsʼ reasons
included cancer symptoms and boosting their immune system. This is unsurprising, as
immunodeficiency is one of the most common issues that cancer patients face during
treatment [35]. Similar
observations have been made in other studies of cancer patients, in which mostly
nonspecific reasons such as improving health or fighting cancer have been reported
[5]. Significantly fewer cancer patients used herbal medicine to treat common colds
or respiratory symptoms.
The present study found that patients with gynecologic cancer used plants less often
than healthy participants. However, when cancer patients used herbal products, they
persisted in using them a lot longer. Although there were no differences between healthy
participants and cancer patients with regard to the numbers of plants used for more
than 8 weeks, cancer patients used less than half as many plants for short periods
of less than 8 weeks. One possible explanation for this could be that cancer patients
are motivated to maintain a constant treatment regimen. In addition, patients with
gynecologic cancer may suffer long-term side effects of cancer treatment and therefore
require long-term care.
Women using herbal supplements and CAM products have previously reported that friends
or magazines were their most important sources of information regarding plant products
[41]. This finding is in accordance with the present study. It is notable that for cancer
patients, physicians were not the first source they consulted about herbal medicine.
Only about half of the patients with gynecologic cancer disclosed their use of CAM,
including herbal medicine, to their treating physician [19], [42], [43]. Reasons for this given by patients ranged from a perception that physicians are
not interested in patientsʼ self-medication to a fear that doctors might discourage
the use of herbal medicines [41]. On the other hand, many patients may wish to receive counseling on integrative
medicine from their treating physician [4], [37], [44]. This shows that it is important for doctors to be aware that patients are using
herbal medicines, and doctors should encourage their patients to tell them which herbal
products they are using. Some herbal products have been reported to have an influence
on cancer or to interact with cancer treatment [16]. For example, phytoestrogens from red clover or black cohosh may interact with hormone-sensitive
cancers, and St. Johnʼs wort is a known CYP3A4 inducer that affects orally administered
drugs [15], [45]. Other plants, however, may be safely administered even while patients are receiving
systemic therapy and may therefore be an attractive option to treat therapy-associated
side effects or symptoms.
The present study has several strengths and limitations. It should be borne in mind
that it was a cross-sectional study. As it was a one time survey, no follow-up data
on the participants was available. The survey was also conducted only at the Department
of Gynecology and Obstetrics of Erlangen University Hospital. Cancer patients or healthy
persons being treated in an outpatient setting were not included in the study. It
should also be noted that the two groups differed with regard to age, with the cancer
patients being on average about 10 years older than the healthy participants.
However, the study also has several strengths. It was possible to include a large
number of participants in both groups, and the drop-out rate was very low. Data were
collected using a standardized questionnaire, which was validated for comprehensibility
and complexity. The group of cancer patients included in the survey included all stages
of disease and treatment and can therefore be regarded as representative. Usually,
the use of herbal medicines is not covered in common hospital questionnaires and little
data is available on the use of herbal medicine by patients with gynecologic cancer.
Gynecologic oncologists should be aware of their patientsʼ use of herbal medicines
and their motivations so that they can provide informed counseling and ensure their
patientsʼ safety during cancer treatment.
Conclusion
This study shows that patients with gynecologic cancer as well as healthy persons
are regular users of herbal products and herbal medicines. However, patients with
gynecologic cancer use herbal medicines significantly less than healthy individuals.
The reasons given for using herbal medicines usually involved treatment of general
symptoms, but cancer patients also use them to treat cancer-related symptoms. This
should be taken into consideration by gynecologic oncologists, and patients should
be actively encouraged to disclose their use of herbal products to their physicians.
It is only when everyone involved has all the necessary information that safe therapy
decisions can made which take the patientsʼ needs into consideration and may improve
cancer treatment.
This is one of the first studies to carry out a systematic evaluation of gynecologic
cancer patientsʼ use of herbal products in comparison with healthy persons. The findings
will need to be confirmed in further studies.
