Kalasekhar Vijayasekharan
The adage that 'the place of one's birth dictates the outcome of one's cancer' chimes
well in no cancer better than pediatric retinoblastoma. Survival outcomes of retinoblastoma
(Rb) approaches 100% in high-income countries (HICs), whereas in low-middle income
countries (LMICs), which harbor 80% of global retinoblastoma burden, the survival
is strikingly dismal.[1] Late diagnosis due to cultural or socioeconomic barriers, lack of information at
primary care level, poor referral to oncology units secondary to deficient health
care system, lack of a retinoblastoma program with multidisciplinary approach, infrastructure
and fragmented care are attributed to poor outcomes in a LMIC setting. Irony abounds
as retinoblastoma is one of those rare pediatric tumors where implementation of a
simple screening program can lead to both preservation of both globe and life.
In this issue, Tan RJD et al. from Northern Luzon in Philippines[2] report the profile and outcomes of 47 children (53 eyes) with RB, who were offered
upfront surgical enucleation/exenteration due to lack of globe salvage options in
the hospital. Extraocular RB patients received adjuvant chemotherapy. The mean age
of diagnosis for unilateral RB was about 2 years and the mean delay in diagnosis from
symptom onset was about 10 months. More than 50% of these patients had advanced disease
and four/fifths of the eyes were enucleated. Overall survival among the whole cohort
was around 50% and none among them with extra-ocular Rb survived.
Hazarika M et al. from India[3] report the outcomes of 189 RB patients from a tertiary cancer care center, where
the median age of presentation was 14 months and the median time to reach the hospital
from symptom onset was only 49 days. Two-third of the patients received computerized
tomography(CT) for staging workup. Three-fourth of these patients had advanced intraocular
disease, and a third had evidence of extraocular disease at presentation. One-fifth
of RB refused treatment and an equal percentage underwent globe salvage. External
beam RT and cryotherapy were the focal therapy modality mainly used for globe salvage
in these patients.
RB affects children between a narrow age range and has a clear natural history, making
it an ideal candidate for screening. Given that RB occurs at an age where routine
visits to the pediatrician are more common and a definite relationship between early
diagnosis and enhanced prognosis for eye salvage and patient survival, screening programs
involving pediatricians and relevant members of the community (school teachers, community
health workers) should be developed. Routine screening for red eye reflex in babies
presenting to pediatricians is recommended by the American academy of pediatrics for
early detection of Rb.[4] However, in a developing country scenario, Chantada et al suggested the key for
eradication of extraocular Rb is related more to the possibility of a country's health
care system granting egalitarian access to health care for young mothers and their
children than any other specific action solely directed to the early detection of
Rb in addition to awareness campaign.[5] At diagnosis, Tan RJD et al. report more than 50% of their patients with advanced
disease[2] and Hazarika M et al. study had around one-third of the patient with extraocular
disease.[3]
Refusal to therapy and poor compliance to prescribed treatment are other major issues
that contribute to poor outcomes of Rb in a LMIC setting. Tan RJD et al. report 18%
of their patient refusing treatment upfront.[1] Also, in developing countries, 50% of the Rb patients drop out during treatment
and 20% of the intraocular patients die of disseminated disease due to refusal for
enucleation of the eyes.[5] One of the reason for good compliance in high-income country setting may be due
to legal system in health care. Such system may be lacking in a LMIC setting, which
may contribute to refusal and lack of compliance to therapy. Developing local comprehensive
supportive care programs relevant to sociocultural background is crucial to address
this issue.
Tan RJD et al. in their study[2] reported lack of access to globe salvage techniques in their hospital leading to
only option of enucleation of eyes for all Rb cases. Intraocular salvage techniques
such as intravitreal therapy, ophthalmic artery chemoinfusions, plaque brachytherapy
are not available in the majority of tertiary cancer centers in developing countries.
In addition to continued training, skill development, adherence to principles of therapy
at a pediatric oncology unit, focused health care policy to allocate adequate resources
at a community level can significantly impact the eventual outcome in Rb in a LMIC
setting.
