A trial looking at chemotherapy and radiotherapy for anal cancer (Act 2)

Cancer type:

Anal cancer

Status:

Results

Phase:

Phase 3

This trial looked at combining different types of chemotherapy with radiotherapy for anal cancer. It also looked at adding 2 further treatments of chemotherapy afterwards. This trial was supported by Cancer Research UK.

Doctors often treat cancer of the anus with radiotherapy and chemotherapy at the same time. This is called chemoradiation. The chemotherapy drugs they most often use are 5 fluorouracil (5FU) and mitomycin. But sometimes this treatment doesn’t work very well and the cancer starts to grow again.

In this trial the researchers wanted to find out

If giving 5FU with another drug called cisplatin instead of mitomycin lowered the risk of the cancer coming back
If giving more chemotherapy after radiotherapy lowered the risk of the cancer coming back

They compared chemoradiation using 5FU and cisplatin with chemoradiation using 5FU and mitomycin. The aim was to find out which of these treatments was best for anal cancer.

Summary of results

The trial team found that 5FU and cisplatin chemoradiation was no better than 5FU and mitomycin chemoradiation to treat anal cancer.

This was a phase 3 trial. It was a randomised trial. The people taking part were put into treatment groups by a computer. Neither they nor their doctor could decide which group they were in.

Of the 940 people recruited

472 had 5FU and mitomycin chemoradiation
468 had 5FU and cisplatin chemoradiation

6 months after the start of their chemoradiation the researchers looked at how well people had responded to treatment. Of the 472 people who had mitomycin they were able to look at the response of 432. They found that in

391 people there was no sign of the cancer – complete response
14 people the cancer had shrunk – partial response
5 people the cancer had stayed the same size – stable disease
22 people the cancer had continued to grow

Of the 468 people who had cisplatin, they were able to look at the response of 431. They found that in

386 people there was no sign of the cancer
24 people the cancer had shrunk
6 people the cancer had stayed the same size
15 people the cancer had continued to grow

After their radiotherapy had finished, they were randomised again to continue with 2 additional treatments of chemotherapy or not.

Of the 472 people who had mitomycin, 226 had further chemotherapy and 246 didn’t.

Of the 468 people who had cisplatin, 222 continued to have it and 246 didn’t.

After 3 years of follow up the researchers looked at how many people were still alive and free of their cancer. Of those, they found that

73 out of every 100 people (73%) hadn’t continued having mitomycin
72 out of every 100 people (72%) hadn’t continued having cisplatin
73 out of every 100 people (73%) had continued to have mitomycin
74 out of every 100 people (74%) had continued to have cisplatin

When the researchers compared the side effects of mitomycin and cisplatin they found that they were very similar. The major side effects were

The trial team concluded that chemoradiation with 5FU and mitomycin should remain as the standard treatment for anal cancer.

We have based this summary on information from the team who ran the trial. The information they sent us has been reviewed by independent specialists (peer reviewed Open a glossary item ) and published in a medical journal. The figures we quote above were provided by the trial team. We have not analysed the data ourselves.