The Cancer Journal - Volume 5, Number 4 (July-August 1992)
Viruses, cancer vaccination and Third World development
In this issue we are publishing two review articles devoted to the possibilities of vaccination against oncogenic viruses, one by Dillner on the subject of papillomavirus and the other, considering EBV, by Arrand. We think that it is important that all cancerologists, whatever their specialization, should be aware of the exact state of the art concerning anti-viral, anti-cancer vaccination. This is where the battle-front is to be found.
The relationship between viruses and cancer, for a long time restricted to the viral hypothesis of cancer and to an impressive collection of murine and avian tumours, has developed in two directions. One is the dicovery of oncogenes and of the role of their products in oncogenesis; the other is the accumulation of a number of results sufficient to support projects for preventive vaccination. Four viruses or groups of viruses seem to be factors, if not or exclusive, at least determinant for carcinogenesis in man. Papillomavirus and the Epstein-Barr virus (EBV) are the subjects of the two reviews; we will briefly mention here hepatitis B virus and HTLV (human T leukemia viruses).
An effective vaccine exists for hepatitis B virus, which is almost certainly the etiological factor for primary hepatoma in tropical Africa and south-east Asia. This is expensive, but it appears that it could be mass-produced at a reasonable cost to vaccinate children exposed to the risk of early, chronic infection. Some trials of preventive vaccination are currently in progress: it is too soon to know what effect they have had on the real frequency of primary liver cancer. At the smallest epidemiological indication confirming a decline in cancer after vaccination, this treatment should be extended, without delay, to the whole population of children at risk.
The same attitude should be adopted if similar results emerge from experimental vaccination against papillomavirus oncogenes and EBV.
Given that the risks due to hepatitis B, EBV and papillomavirus are more prevalent in developing countries, it would be unjust and ethically inacceptable if doctors and scientists working in rich countries dissociate themselves from these projects, or simply do not pay attention to them. The two review articles published in this issue should help them to remain informed. The case for anti-viral anti-cancer vaccination should be put forward by all available means. We cannot be certain that one or more of these vaccination programmes can really reduce the frequency and mortality of these cancers, but until there is clear experimental proof to the contrary we have no alternative and the field work must be carried out urgently, with adequate resources. At the risk of upsetting some, I dare to say that this is more urgent than the massive genetic projects. There are millions of years of life to be saved. Epidemiologists from the WHO are aware of this. They have said it in writing; but they are far from gaining the support of cancerologists and pressure groups from the developed countries. Of course, as for any project carried out in a developing country, many difficulties are encountered, very different from the problems of experimental and clinical research. As we said above, it is not certain that any one of these vaccinations, by itself, will be able to reduce the incidence of liver, nasopharyngeal, uterine cervical or anal cancer, or lymphoma or leukemia, to name only the best known examples, but this is highly probable. Probable enough for the scientific community to adopt these projects as a priority, to exerce pressure in this direction on the powers-that-be and to support the efforts of the WHO, UNICEF, governmental and non-governmental organizations. The time is ripe for this sort of action. The Rio summit was frustrating for both the North and the South. This is the moment for researchers and clinicians, so numerous in the North and so few in the South, to define some objectives for health on a world scale and to intervene with determination, as one can and should intervene in the fight against tobacco consumption. As for tobacco use, the positive effects will only be evident after a long delay; this should be understood and proclaimed by all the participants. Luckily, in contrast to tobacco, viruses have no commercial value; therefore there are no powerful economic interests opposing action.
Of course, we will have to feed all those people who gain years of healthy life from these programmes, we will also have to educate them and find them work to do. We should think of and prepare for this now. We must be able to assess the demographic impact of this wholely justified action which we are proposing to our colleagues. Today, one cannot be a doctor, cancerologist or social scientist without being involved, in one way or another, in the most realistic applied anti-cancer project of present-day science.