We all want a cure for cancer. This is evident in the ideas put forward for the NZ Science Challenges (http://www.thegreatnzscienceproject.co.nz/home). Will these ideas reflect the true need in New Zealand? Are all cancers equal or are some more equal than others? Does the public perception of what is most important reflect the true health risks? To answer this latter question would require a well controlled survey which I don’t have. What I can do is look at some data from the media.
First the numbers: The Table below gives the number of newly diagnosed registered and of deaths in New Zealand for various cancers for 2009 (I have only considered those with more than 200 deaths). The percentages are the percentage of all the cancers listed. The final column is the ratio of the numbers who died to the number of newly diagnosed. This is not a proper measure of the likelihood of dying of the disease once it is diagnosed, but probably gives an impression of which are the more and which are the less deadly of the cancers.
Cancer Registrations and Deaths in New Zealand (2009: Ministry of Health, http://www.health.govt.nz/publication/cancer-new-registrations-and-deaths-2009)
The graph plots the percentages for new Diagnoses and deaths against the percentage of stories on the Stuff.co.nz web site for each of the cancers (ie relative to the total number of stories (20,757) for all these cancers. I’m sorry to pick on Stuff, but it conveniently gave a count with a fast search engine. The area above the dashed line (blue) suggests under reporting in the media, the area below over reporting. Brain cancer is vastly over reported on this measure relative to other cancer death rates and new registrations. Breast cancer is also over reported, particularly in relation to other cancer death rates. Melanoma reporting reflects its deadliness, but not its new registrations. Colorectal/Bowel cancer and Lung cancer are relatively poorly discussed compared to their relative death rates.
The percentage of new registrations and of deaths of various cancers against the percentage of stories in Stuff.co.nz. Note, percentages are relative to the total number of new registrations/deaths/stories
There may well be many better ways to look at this kind of data – I would appreciate any suggestions. I hope to look at other diseases as well. However, as I research a disease that affects as many people as breast cancer each year, is just as deadly, and yet is reported on Stuff 1/50th as often, I am a little biased.
Tagged: brain cancer, breast cancer, cancer, lung cancer, media, melanoma 
I am not sure where you coming from or where you’re going with this. In particular, I struggle with the word “equal”. You do probably know that not all cancers are similar. In fact, inter- and intra-patient but also intra-tumour heterogeneity is enormous; one tumour can contain very many mutations, for example, but these will not be evenly spread throughout the tumour. The cancers in the table are listed by site but there are a number of breast cancers, for example; triple-negative breast cancer is known to spread to the brain so is this a brain or a breast cancer and what is the cause of death? The other issue is ease and time of diagnosis; early diagnosis can save lives. The Ratio in the table is a little problematic. For example, in 2009 there were 6 registrations of cancer of the heart (C38) and 9 deaths, which gives a ratio of 1.50. The point is that from the numbers in the table alone you cannot draw conclusions about prognosis and life expectancy. In total there were 8437 deaths from all cancers in 2009 and 20875 registrations, which gives an average ratio of 0.40 (0.43 in 2007 and 0.42 in 2008).
You also mentioned “public perception”. That is a hot potato. A very recent study reported in the New England Journal of Medicine was entitled “Patients’ Expectations about Effects of Chemotherapy for Advanced Cancer” (Preview is free; http://www.nejm.org/doi/full/10.1056/NEJMoa1204410) and concluded that “Many patients receiving chemotherapy for incurable cancers may not understand that chemotherapy is unlikely to be curative” and went on to say “Physicians may be able to improve patients’ understanding, but this may come at the cost of patients’ satisfaction with them”. I think it is fair to say that in NZ there is similar levels of confusion and lack of understanding, certainly among the wider general public. Cancer is enormously complex and it is therefore extremely difficult to develop successful therapies.