Pregnancy should make no difference to treatment for breast cancer

Pregnant breast cancer patients should be treated as closely as possible to existing guidelines for non-pregnant patients, a scientist told the 6th European Breast Cancer Conference today.

Dr. Sibylle Loibl, Assistant Professor in Obstetrics and Gynaecology at University of Frankfurt, suggested that current levels of treatment for pregnant women were too cautious and may disadvantage their treatment.

"We realised that there are hardly any data on this subject," she said, "and therefore set out to collect information from patients in Germany and throughout Europe."

The German Breast Group launched a data-collection exercise in 2003 in line with the Breast International Group (BIG). They analysed information on 122 pregnant patients diagnosed with breast cancer between April 2003 and December 2007 for a number of factors such as foetal outcome four weeks after delivery, maternal outcome of pregnancy, stage and biological characteristics of the breast cancer, breast cancer therapy, sensitivity and specificity of diagnostic procedures, outcome of the child five years later, and outcome of the breast cancer five years after diagnosis.

The median gestational age at the time of diagnosis was 21 weeks, and the median age of the women 33 years. Some patients chose not to continue the pregnancy on learning of their diagnosis, but of those who did, 33.3% received surgery only, 43.2% were treated by surgery and chemotherapy, 5.4% by chemotherapy alone, and 2.7% had no treatment at all. The median time for delivery was 36 weeks, slightly earlier than normal in healthy women.

Dr. Loibl stated that the only discernible negatives are a slightly below average birth weight, and a possible low blood count where the baby is delivered within one week of chemotherapy; in turn resulting in an increased risk of infection on delivery. She described these problems as "minor" stressing that "the foetal outcome in babies whose mothers received chemotherapy was not different to those whose mothers did not", but admitted that there was very limited research into the transfer of chemotherapy drugs through the placenta.

The team are still analysing the data but are confident that their primary endpoint, foetal outcome four weeks after delivery, is strong enough to justify pregnant patients receiving the same treatment as non-pregnant. They also suggest that treatment should take place in multidisciplinary centres.

The trial is limited by the rarity of patients, just 1-2% of all breast cancers are diagnosed during pregnancy, but there are plans to increase the dataset to 200 patients by the end of the year; the largest data collection yet concerning breast cancer during pregnancy. This is still too small admits Dr Loibl, calling for "some kind of fast-tracking" to be able to get a much larger trial underway.

"We hope that in the future we may be able to conduct larger trials in such patients and gain further important data. Treatments are improving all the time, and new drugs are on the horizon waiting to be implemented into the adjuvant therapy of breast cancer. The training of doctors to deal with pregnant breast cancer patients and the centralisation of information on such patients will help raise awareness of the issues involved".

Watch an interview with Dr. Sibylle Loibl on ecancertv here.

Details on how to register a patient for the trial can be found on the website of the German Breast Group.