CRISP-1 is a study to see if a food supplement (BioResponse-DIM Ò) could be useful in the treatment of women with minor abnormalities on their cervical smear. The study is being conducted with the full support of Cervical Screening Wales within the department of Obstetrics & Gynaecology at University of Wales College of Medicine. The research is funded with a grant from Cancer Research UK.

Approximately 6% of screening smears in Wales are classified as having a low-grade cytological abnormality (borderline changes or mild dyskaryosis). CRISP-1 is designed to see if we can offer better health care to those women. Currently, women with such a smear are invited to be re-tested after six months. If the second (in the case of mild dyskaryosis) or third smear (in case of a borderline abnormality) is abnormal, the woman is referred to a gynaecologist for an examination called colposcopy. If a high-grade lesion is identified at colposcopy surgical treatment is recommended. The idea of CRISP-1 is to see whether by taking capsules of DIM for six months, the minor abnormalities will go away and fewer women will need colposcopy and surgical treatment.

Diindolylmethane (DIM)
Diindolylmethane (DIM) and Indole-3-carbinol (I3C) are related substances naturally occurring in vegetables such as cabbage. They have been identified as compounds that could potentially prevent or halt the development of cancer. Infection with one of several types of human papillomavirus (HPV) is a necessary step in the development of cervical cancer. A small trial in women with high-grade cervical abnormalities was undertaken in the USA. Over 12 weeks, the abnormalities cleared in eight of 17 patients receiving I3C, compared to none of 10 patients receiving sugar tablets.

Research suggests that DIM is the major active by-product of I3C and that it may be better tolerated than I3C.

Recruitment
Potentially eligible women will be identified and contacted by Cervical Screening Wales. Those wishing to participate will be given an appointment at which they will complete a questionnaire, provide cervical smear sample and be given a supply of capsules to be taken for six months.

The Study is not open to pregnant women.

This is a randomised study. Neither patients not their doctors will know whether they receive DIM or placebo, but two-thirds of women participating will receive DIM. The DIM in the study is provided by the US company BioResponse.

Participating women will be asked to return after about three months to complete another questionnaire and to provide a hair and urine sample. They will then be offered colposcopy six months after entering the study. In this way, all participating women will get to see a gynaecologist earlier than they would if they were not in the study. Management after the first colposcopy appointment will follow standard guidelines.

Study size

It is hoped to study 3000 women with mildly abnormal smears. A preliminary analysis will take place once 300 women have completed the study.

Side-effects

The BioResponse, LLC formulation of DIM has been allowed unrestricted human use as a dietary supplement after review by the FDA. It has been sold in the US since 1998.

Not all reported side effects are bad. There are suggestions that DIM relieve premenstrual symptoms including breast pain. Additionally DIM may facilitate weight loss in women on a low carbohydrate diet.

If you have any concerns about a potentially serious side-effect please stop taking your capsules contact the study team immediately.
Similarly, if you become pregnant please stop taking your capsules contact the study team immediately.