Coffee and cancer, a translation

Image: Izabela Latak

During cancer treatment I started drinking coffee, through my mouth. That’s an important distinction in the cancer world because many people with cancer consume coffee through another hole in their body – the bum (more on that in a moment).

Once someone gets cancer they develop a radar for things that will help them stay alive. Some of these things come from doctors and some from family and friends, but the bulk of Things That Will Save You come from people who have written popular books, blogs or invented diets and ‘cancer-busting’ treatments.

Coffee is one of the most commonly suggested and debated of the Things That Will Save You. Cancer doctors don’t have much to say about coffee, but the complementary and alternative medicine field is full of ways to use coffee – one of which is pouring warm black coffee into your bottom, holding it there for a little while and then letting it drain into the toilet.

There is no evidence that drinking coffee through your bum has any effect on cancer. But there is evidence that drinking coffee through your mouth may.

A study recently made headlines when it found that drinking (through the mouth) four cups of coffee (or more) per day can drastically reduce the chances of colorectal cancer coming back. People that drank this amount of coffee were also less likely to die from their cancer.

The curse of having studied science before cancer and now studying medicine after cancer means I can’t just go with the news headline, dress like George Clooney and buy a Nespresso – I need to look at the details.

If this study was about eating 2 bananas a day, or sipping a shot of apple cider vinegar each morning, I probably wouldn’t bother – but 4 cups of coffee per day is a serious commitment and if I am going to expose my brain and heart to that amount of caffeine I need to understand the benefits.

So, for those of you that avoid dense scientific studies, here’s a translation on what you need to know. 

The study: Coffee Intake, Recurrence, and Mortality in Stage III Colon Cancer: Results From CALGB 89803 (Alliance).

The journal: Journal of Clinical Oncology. This is a good journal which only publishes the top 10% of papers sent to it.

The main author: Dr Charles Fuchs, Director of the Gastrointestinal Cancer Center at the Dana-Farber Cancer Institute.

Why study coffee and colorectal cancer?

Image: Daniel Schwen

The logic is:
A. Coffee protects against Type 2 Diabetes.
B. Type 2 Diabetes involves high sugar and high insulin in the blood.
C. Colorectal cancer likes high insulin and high sugar in the blood.
D. If coffee works against Type 2 Diabetes it may also work against colon cancer.

How was this study done? This study did not start off by looking at coffee. The researchers have pooled a previous big clinical trial that compared [5FU + leucovorin] with [5FU + leucovorin + irinotecan] in people with stage III colorectal cancer. Because there was no difference in the outcomes after either chemo the researchers are able to chuck both groups together into one big database and ask different questions about people with stage III colorectal. They are tracking the people from the original study over time, so they know when they die or get sick again.

How did they measure coffee? They gave people a survey about foods and eating patterns halfway through chemo and then 6 months after chemo was finished. They then tracked these people over time. The average time of tracking was 7 years.


What did they find? They compared the number of cups of coffee consumed each day and whether someone's cancer came back and whether they died from their cancer.

They analysed the data two ways. In the first way they looked at people who drank 0, <1, 1, 2-3 and 4 cups of coffee or tea per day and measured when their cancer came back or if they died from their cancer. This showed that ANY coffee helped, and people that drank 4 cups a day had the greatest chance of survival.

In the second way they grouped everyone into two groups (no coffee per day vs 2 or more cups per day). This also showed that all the people who drank 2 or more cups per day had a greater chance of survival.

Couldn't something else explain this? Yes, maybe. This is not a randomised controlled trial (the gold-standard in medical research) so it can't say that coffee is the reason those people lived longer and had less cancer recurrence. But, the authors did control for HEAPS of factors that they know affect colorectal cancer recurrence and survival (BMI, sugary drinks, age, gender, lymph node involvement, a Western diet, exercise, chemo and smoking).

Because the research took all these factors into consideration, they are able to say: When you compare two overweight smokers who drink a lot of Coke and don't exercise, the one that drinks coffee will have a lower chance of dying from their cancer. You could pick any of the factors they 'controlled for' and make similar comparisons.

Gimme the nutshell: The study has 1000 people in it with stage III colorectal cancer, but the numbers of people in each group of coffee drinkers are much smaller, and in the ‘4 cups per day group’ the total number of people is only 62. The protective effect of coffee is dose-dependent, which means any coffee is good and 4 or more per day is best. This is a correlation, not causation, and the authors admit there may be another factor responsible for the pattern they found. The pattern they found is a strong one though and the Journal of Clinical Oncology is a robust and well-respected journal.

In a New York Times blog about this study (the best reporting of the study that I found), the main author says that patients shouldn’t start drinking coffee because of his study, but, “If you’re a coffee drinker and enjoy it, stick with it”. For coffee-haters he suggests adopting Things That Will Save You where the evidence is clear-cut: “avoid obesity, exercise regularly and follow a balanced diet.”

What's going on with coffee? Science doesn't know yet. It could be that coffee makes cells in the body less sensitive to insulin. It could be that coffee works as an antioxidant. It could be that coffee is anti-inflammatory.

Where was tea in all of this? They didn't classify types of tea consumption - just herbal and non-herbal. No mention of green tea. This is the US and I suspect tea is not as common a part of their diet as it is in ours.

Is it coffee or caffeine that is important? The decaf coffee consumed by the cancer survivors in this study had no effect on survival. Only actual coffee did.

So, my thoughts after reading this are that I like coffee and will keep drinking it. If I didn’t drink coffee and wanted to start I would print off the study (or at least the abstract) and take it in to the next appointment with my GP or oncologist and get their opinion.

Fear and alternative medicine

Soon after my cancer diagnosis I told my surgeon that I was uncomfortable about the upcoming surgery and did not want him to remove all my contaminated organs.
 
In a small, crowded clinical room I pleaded: “Can’t you just take the colon, or rectum and leave my bladder and reproductive organs alone? Can’t I just delay the surgery for now and spend the next six months working out, eating healthy, and meditating?”

I was diagnosed with stage three bowel cancer in 2011 at the age of 28. At the time I was terrified. I was facing chemo, radiation, and major surgery that could have left me, if I survived, with permanent bags hanging off my body and erectile dysfunction.

And so I launched head first into exploring other therapies. They gave me a sense of power over my body – like I could have an effect on the outcome of my cancer, and it wasn't in the hands of others alone.

My doctors didn't agree. At the meeting they warned me, unequivocally, that they don’t usually see people who have tried alternative methods – as promoted by the now disgraced Belle Gibson – “until they are crippled by pain and it’s too late to save them”.
 
With the recent passing of alternative therapy ‘Warrior’ Jessica Ainscough after a 7 year-long battle with epithelioid sarcoma, a rare cancer affecting the hands and arms, and the collapse of Gibson’s fake cancer healing empire, alternative medicines have been pushed into the public eye.

Exactly how many people turn down conventional treatments for alternative ones is unknown because hospitals don’t measure it. Hard data is also lacking because studies tend to group complementary and alternative therapies together – even though they represent very different attitudes towards mainstream medicine.

Most people believe that alternative therapies are safe, despite the fact that they aren’t subjected to rigorous analysis. The risks of alternative medicines are rarely communicated by those selling them, especially the biggest risk of all – missing that small window of opportunity to hit a cancer with the best treatment possible, usually aggressive chemo, radiation or surgery.

Wellness therapies don't work alone. But maybe we should also preach some patience and understanding to those who turn to them so we can support them to make decisions that ensure the best chance of surviving. I am a scientist yet – four years ago, faced with a life-threatening illness – I suddenly considered abandoning science. Why?

Quite simply, I was very scared.

In the end I followed my doctor’s treatment plan – but I also kept meditating, drinking apple cider vinegar, went vegan, and began to see complementary healers. Faced with fear and frustration, these more gentle treatments seemed a universe away from the sickness and pain of chemo and surgery. They gave me hope.
 
Why were people so duped by Belle Gibson’s lie? Why was Jessica Ainscough (who I met at a cancer meeting and was lovely) seen as so brave and all knowing? Both are a reminder that people are complicated, emotional creatures, especially in times of stress and fear. They want a bit of magic and a few miracles.

I started my training this year to be a doctor. And one of the most important lessons we learn as doctors is that people need to be emotionally propped up through major medical decisions. Support during the decision-making process, when dread and anxiety are elevated, is fundamental.

Gibson and Ainscough sold therapies that aren’t proven – but remember people believed in them because they were afraid. I know because I've been there and danced with the dangerous idea of abandoning medicine, at a time when I needed it most.

Next steps

I start medical school next week and my stethoscope arrived two Tuesdays ago. I bought it online.

I never thought that one day I would end up browsing online stethoscope stores. It didn't cross my mind, for example, while I was lying motionless under beams of radiation. And I certainly wasn't thinking about it while watching nurses change my bags of chemotherapy solution.

Was it before a particular surgery? Or after? Nah, I was definitely focused on other things then, like trying to eat without throwing up.

It’s a shame I can’t remember, it would be nice to have an ‘Ah-Ha’ point in time – the exact moment my motivation and values shifted and I decided I wanted a career in medicine.

Plenty of cancer survivors have gone into medicine or medical research. And plenty of doctors and health professionals have developed cancer. What I’m doing isn't anything new.

But I thought I would mention it here because this blog is about one person’s cancer journey, and that journey means I am now crossing the line between patient and doctor...and I am doing that because of cancer.

Next week I begin a new journey and dive head first into the system that saved me.