COVID-19 Pandemic and Childhood Cancer

None of us has ever seen anything like this before. And I am not talking about a viral infection. I am talking about the emergence of a new infection and the global and national response to it which has been without parallel. Over the last few months not only has the infection affected the health of millions and taken the lives of hundreds of thousands, it has brought the world to a HALT! Individuals, businesses and countries have borne the brunt of it and continue to do so.

It will be some time before this comes to pass. Meanwhile children with cancer (like those with many other illnesses) have been caught in this maelstrom with impact on their diagnosis, their treatment and eventually outcomes. In the face of such ongoing challenges, the global and the national pediatric oncology community has got together to respond on multiple fronts in many different ways.

The Global COVID-19 Observatory and Resource Center for Childhood Cancer is one such effort. Developed by SIOP and St Jude Global, this Resource Centre provides all relevant information to those caring for children with cancer including parents and families. The reader is encouraged to browse the website for further information.

Specifically I wanted to highlight two things.

Firstly, are the weekly COVID Conversations - a live webinar to discuss difficult issues, address pressing questions, and hear the experiences of our colleagues when it comes to caring for children with cancer during this pandemic. Several such Conversations have happened with one specifically relating to Experiences in India and Pakistan.

Secondly, is the Global Registry of COVID-19 in Pediatric Cancer which provides a visualisation of the impact of the virus on our patient population.

What is the outcome of children with Acute Lymphocytic Leukemia (ALL) in India?

The answer to this question, depends on whose asking it and to what purpose. At an individual level (when access to treatment is not a barrier), currently the standard 5-year survival in most of the developed world is 80-90% with that for low-risk ALL even higher than 90%. The best published results from India are 59% 5-year survival for children with ALL treated from 1985 to 2003 in CMC Vellore (Bajel et al, 2008), and of 57% in those treated from 1990 to 1993 in Tata Memorial Hospital, Mumbai (Advani et al, 1999). For low-risk ALL, these survival figures are around 73-77%. It is important to point out, that these results from India are calculated after censoring (removing) those children with ALL who refused to start treatment or abandoned ongoing active treatment. There are some unpublished data suggesting better outcomes - 70% 4-year survival of children with ALL treated at Sir Ganga Ram Hospital in Delhi (Sachdeva et al, SIOP 2007); and 94% survival after median follow-up of two years of children with ALL treated at Apollo Hospital in Delhi (Mahajan et al, SIOP 2008). A more accurate reflection of outcomes of children with ALL in India can be obtained when we include all those who refused and abandoned treatment and then calculate the survival. This is particularly relevant to clinicians, epidemiologists and health planners. To my knowledge, the recent paper from PGI in Chandigarh is the only one to publish such data. It shows a 4-year overall survival of 33% and a 10-year overall survival of 30% for children with ALL diagnosed at that institute from 1990 to 2006 (Kulkarni et al, 2009). Other sources of such information are the population-based cancer registries. Only two reports have ever been published looking at population-based 5-year survival in children with cancer and these were 35% from Bangalore for the period 1982 to 1987 (Nandakumar et al, 1996); and 39% for Chennai for the period 1990 to 2001 (Swaminathan et al, 2008). In a nutshell, 6 out of 10 children with ALL in India will have long term survival (and cure) if they are compliant with their treatment. If treatment uptake and compliance is variable, only 1 out of 3 children in such settings would be cured. These outcomes apply only to those treated in specialist tertiary centres in urban areas. For those in rural areas or non-specialist centres, the outlook is certain to be worse.

Childhood Cancer Survival in Philippines (and India) lags by >30 years than in Developed Countries

Survival of childhood cancer has enormously improved in the developed world with current 5-year survival for leukemia and lymphoma now around 80% and 90% respectively. An interesting recent paper shows that for the period 2001-2005 the 5-year survival of children with these cancers in Philippines is much lower (32.9% for leukemias and 47.7% for lymphomas) (Redaniel et al, Br J Cancer, 2010). These figures are even less than the survival seen in USA during 1976-1980 (57.7% for leukemias and 60.9% for lymphomas). These observations although not unexpected, do highlight the enormous gap in the outlook of children with cancer in the developing world.

What about India? There is limited population-based childhood cancer survival data. The most recent data from Madras Metropolitan Tumour Registry shows that for the period 1990-2001 the 5-year survival of children with leukemias in Chennai was 36.3% and lymphomas was 55.3% respectively (Swaminathan et al, Int J Cancer, June 2008). In this study, a combination of completeness of treatment and type of hospital emerged as significant prognostic factors for survival.

Incidence of Childhood Cancer in Rural India

Although 70% of the Indian population lives in villages, we have relatively little real information about cancer in them as most of the population-based cancer registries (PBCRs) are urban. The incidence and mortality patterns of these urban PBCRs cannot provide an accurate picture for the entire country as the environmental exposures and the gene-environment interactions leading to cancer could be substantially different within different part of India.

In such a context the first report of the rural PBCR at Dindigul Ambilikkai in Tamil Nadu provides us useful information about cancer incidence (including childhood cancer incidence) in rural India (Ref - Swaminathan et al, Cancer Epidemiology, Nov 2009). The reported incidence of cancer in boys less than 15 years of age of 56 million person years and in girls of 46 million person years is similar to reports from the two other rural PBCRs in India and much less than that reported from the urban PBCRs in India and from other parts of the world (Ref - Arora et al, Indian Journal of Cancer, Oct-Dec 2009).

Under-diagnosis (and consequently under-registration) of childhood cancer due to lack of adequate access to diagnostic and clinical services is likely to be the main reason for the lower incidence of childhood cancer seen in rural India (Ref - Arora, Cancer Epidemiology, Feb 2010) and (Ref - Swaminathan et al, Cancer Epidemiology, Feb 2010)