So, the combination therapy of chemotherapy (Irinotecan) and monoclonal antibodies (Cetuximab) has finally come to an end. I was down for 6 cycles of chemo and 6 of cetux but the latter started later so in all I have had 8 cycles of chemo and 6 of cetux. A little bit extra for my loyalty I guess. I usually measure the impact of these cycles on a scale “did this negatively impact my life” and once again I have to say “not really”.

Next Tues I go for a CT scan to see what impact the last 5-6 months has had on the tumour. I will know the results around a week later.

Hopefully, the tumour will have shrunk from its 3.9cm size to something around 1cm or less. That will increase the chance that they can go after it with either direct ‘cut it out’ surgery or radio frequency ablation (which involves heating up the tumour until the cells die – a sort of surgery). It’s not guaranteed even if the tumour has shrunk. A lot also depends on location (near to artery, etc.). The alternative is proably to resume more chemo, not necessarily immediately but maybe in 3-6 months time.

I quite like the sound of Radiofrequency Ablation. It sounds like the title of a Kraftwerk album from the seventies. That has to be a clincher in my decisions.

There hasn’t been a lot of time to ask prognosis questions, and anyway the consultants duck them at this stage because they want to see the outcome first. So I’ve been guessing on the probability and trying to find research results.

I found one study that said response to treatment was 4.2% for irinotecan alone and 16.4% for irinotecan and cetuximab combined. They also found that the cancer stopped growing for longer when people had both treatments. It may be 4 times better but 16% is still a low number.

In another early stage trial, a combination therapy of the drugs vermurafenib, cetuximab and irinotecan  was good for 50% of patients with advanced colorectal cancer. All I know about Vemurafenib is that it was developed for the treatment of late-stage melanoma, but in 2010 they started using it for solid tumors such as colorectal cancer). The common link in these drugs is that they act on the receptors that control cell growth. These are called epidermal growth factor receptor (EGFR). They especially target the cells with the most aggressive growth: cancer cells.

There are some amazing animations on the web – complete with Games of Throne style music that show the process in action. It’s therapeutic to watch them and think “that’s going on inside me right now, take that you bastard cancer cells”. The image shows the nice baby blue cetux blowing up the nasty black cancer cell that it has locked onto.

All in all, I reckon that I have a 1 in 4 (25%) chance that the outcome will be good (=surgery) but the alternative (=wait) isn’t the end of the world either, as long as the tumour has shrunk and growth is arrested.