DISCUSSION
Adherence to treatment for retinoblastoma was low in the Ivory Coast and
the DRC with 22.3% refusal of chemotherapy, 45.1% refusal of
enucleation, 27.4% abandonment of treatment, and 18.3 % loss to
follow-up after treatment.
The global rate of refusal and abandonment of treatment for childhood
cancers is recorded; however, results are distributed unevenly with less
than 10% of cases in high-income countries5. In
contrast, it can reach up to more than 90% in low-income
countries5 where the refusal of enucleation can go up
to 100% of cases7. Ye described 35.8% of
chemotherapy refusal cases in China16, while
Malliptana reported 0.8% of refusal cases in a series in
Canada17.
There has also been a regional disparity in the rate of loss of
follow-up worldwide: 13 to 16% in some countries with limited
resources16,18, 18 to 36% in some African
countries19,20, and lower rates in developed European
countries such as Italy where 5.6% of patients were lost to follow-up
during treatment for retinoblastoma by intra-arterial injection of
melphalan21.
Our chemotherapy refusal rate matches other low- and middle-income
countries. The financial difficulties, which are the main causes of the
refusal of chemotherapy in our environment, could reflect the
inaccessibility to medical care in most French-speaking sub-Saharan
African countries22,23. Enucleation refusal rates like
ours have been described in sub-Saharan Africa, where a large proportion
of deaths related to enucleation refusal have been noted in the absence
of care improvement programs24,25. The most frequent
causes are belief in traditional treatments or the fatality of cancer as
well as fear of the aesthetic outcomes resulting from surgery, and fear
of stigmatization7,26. Despite the similarity to other
low or middle-income countries, our results had the distinction of
having financial difficulties as the second cause after the fear of
infirmity.
Bilaterality was a factor that influenced the refusal of enucleation in
our study, which was similar to the findings of a series in
India27. In our countries where conservative treatment
is not well developed yet, the fear of bilateral enucleation could
explain this parental attitude.
In this study, which is the first of its kind in French-speaking
sub-Saharan Africa, we found that the absence of secure management of
medical care, the unmarried status of parents, the low level of
education, and the low qualification of the parents’ professions were
determinants and predictors of the refusal and abandonment of treatment.
Financial difficulties are the main causes of abandonment of treatment
described in other countries, particularly in
Asia27-30. Other causes include the fear of
enucleation27,28, and difficulties related to travel
for families who live far from care centers29,30. In
Africa, financial difficulties and the unavailability of drugs are
reported as reasons for abandoning treatment3 due to
poor funding through social security and health insurance systems. In
principle, we reported similar causes, and fear of side effects
(including fear of the consequences of enucleation) was among the causes
of discontinuation of treatment. Moreover, difficulties in traveling to
the specialized center and the unavailability of medication may be the
consequences of financial difficulties.
Consultation with the traditional healer is a particularity that we
found to be a predictor of the abandonment of the treatment. This could
be explained by the fact that those who resort first to this category of
health professionals believe less in the effectiveness of modern
treatment. However, we do not have a particular explanation for the
influence of consulting other health professionals (nurse, general
practitioner, pediatrician) on the refusal or abandonment of treatment.
Furthermore, we had many more dropouts when the treatment started with
chemotherapy: this may be due to the fact that the parents dropped out
of the treatment at the time of enucleation; whereas the opposite was
observed in Latin America, where neo-adjuvant chemotherapy made it
possible to accept enucleation in a certain number of
children3,31. Perhaps our families were less prepared
for enucleation, even when chemotherapy treatment was started.
Ultimately, the financial difficulties of the parents and their
understanding of the disease and its treatment are major determinants of
refusal and abandonment of treatment. Psychosocial and financial support
programs for families (with better communication on the ocular
prosthesis, the prognosis, etc.) can improve adherence to treatment for
childhood cancers and survival, as has been proven
elsewhere32,33.
Survival linked to retinoblastoma varies greatly according to geographic
location. In developed countries, survival is more than 97%34, with preservation of vision in at least one eye
reaching 90% of cases2. However, in several African
and Asian countries, the mortality rate varies between 40 and 70%35. Socioeconomic factors as well as the refusal and
abandonment of treatment contribute to this high
mortality3,35. The 56% 3-year survival rate found in
our study is consistent with rates found in sub-Saharan African
countries. Most of the patients who dropped out of treatment did so
within the first 6 months. This matches the results of a study in East
Africa where retinoblastoma-related survival was difficult to estimate
because most children were lost to follow-up during the first year of
treatment36.
Advanced forms of retinoblastoma are generally associated with low
socioeconomic status37 which negatively influences
(with refusal or abandonment of treatment) survival35,
as observed in our study.
The median age at diagnosis is 14 months in high-income countries and
30.5 months in low-income countries37. Age was
slightly higher in our study as was the number of cases with advanced
forms of retinoblastoma. This may be explained by the association of
advanced age with advanced forms of retinoblastoma37.
The sex ratio was approximately 1 in our study. Other studies reported
that there is often a slight male predominance without any impact on the
evolutionary forms or survival37,38. Nevertheless,
studies from India occasionally report a predominance of the refusal or
abandonment of treatment in females, which probably follows the cultural
discrimination in favor of boys in the attention granted to medical care
by parents27.
Siblings are not described as a factor affecting treatment adherence.
However, the number of people per room in the house is involved in the
calculation of certain indices of socioeconomic level, which influence
treatment39. We can estimate that a large number of
children per family is associated with a low socioeconomic level which
would lead to difficulties in accessing medical care.
One limitation of our work was that we were unable to find all the
information we wanted in the retrospective files despite the effort to
complete them by telephone. However, this study has identified the main
factors influencing adherence to treatment in our settings. This
information could be better supplemented by a subsequent qualitative
study.