The 12th Breast Cancer Conference, also known as the Consensus Conference, took place in St Gallen from 16-19 March 2011. Together with the annual congresses in San Antonio (San Antonio Breast Cancer Symposium) and principally Chicago (ASCO – American Society of Clinical Oncology), as well as the biennial European Congress (2010 in Barcelona; 2012 in Vienna), the biennial St Gallen conference is ranked among the most important in the world. The reason for this is that on the last day of the congress, fifty of the best known specialists in the world (medical oncologists, surgeons, radiotherapy specialists, researchers) vote on the most burning topics relating to breast cancer treatment.
Among the topics which were debated in the past few years, there was no longer any need to take a vote, for example, on the following:
– Sentinel lymph node biopsy if lymph nodes are unaffected
– Shrinking of large tumours by medical means, in order to facilitate breast-conserving surgery
– Use of Herceptin if Her2 gene is present (or over-expressed)
– Possibility of simultaneous reconstruction in the case of total mastectomy in all cases where no radiation of the chest wall will be necessary
There were many questions to which we would like to have the answers, but which could not be answered because we are still awaiting the results of the relevant studies, e.g.:
– in pre-menopausal women, should we suppress ovarian function at the same time as giving Tamoxifen (e.g. with 3-monthly injections, either Zoladex or Lucrin)?
Some new studies have been published in the meantime and based on the results of these studies, it has been possible to formulate new recommendations:
Lymph node surgery is less often required
The most frequently discussed innovation relates to lymph node surgery. According to an American investigation in which lymph node surgery was avoided, in cases where the sentinel node was shown to be affected it was evident that extraordinarily few of the residual lymph node metastases went on later to cause problems. In spite of the fact that the follow-up covers a period of only 6 years (at which point most patients are still receiving anti-hormonal therapy) and it is therefore not clear how this will look, for example, after 10 years, the majority of experts (76.7% in favour, 4.7% abstentions, 18.6% against) found that in micrometastases (up to 2 mm diameter), complete lymph node removal can be avoided. This applies, however, only to the patient group covered by the study: breast-conserving surgery with radiation (in which a part of the lymph nodes are also radiated) was always carried out, the tumours were smaller than 5cm (with few over 3cm), in all cases earlier examinations (palpation of axilla, sometimes with ultra-sound) showed normal lymph nodes and no more than 3 lymph nodes were affected. No vote was taken on whether larger metastases might also be accepted. And when no radiation is carried out (for example in the case of total mastectomy where radiation is not necessary) these conditions are not applicable.
Must radiotherapy always last 5-6 weeks?
Recent studies show that in many cases a shorter term (4 weeks) is sufficient. This development was endorsed by a good 90% of experts.
Is a one-off, partial breast radiation sufficient (e.g. during surgery) in certain cases?
48.9% voted yes on this question, 35.6% voted against and 15.6% abstained
Should chemotherapy always be prescribed together with Herceptin?
The answer was yes. It would require very particular circumstances for Herceptin to be used without prescribing chemotherapy.
Should chemotherapy be recommended together with Herceptin in the case of Her2-positive tumours measuring 5-10mm
Yes, this was unanimously agreed upon.
For patients taking Tamoxifen, should one measure the CYP2D6 enzyme, in order to ascertain if the product is effective in the patient?
No. Earlier studies were inconclusive and it would seem that Tamoxifen is effective even in those whose system rapidly breaks down the drug.
Is the Oncotype DX or Mammaprint gene test always appropriate?
No, only in certain cases is this useful
Is the uPAI-1 an accepted test (used/recommended in Germany)?
No, two-thirds of the experts do not find this test useful
The above represents a selection from the questionnaires processed from the conference.
In addition, some recent results and experiences came up:
Vitamins: Carotin, Vitamin A und Vitamin E might actually be harmful. On the other hand care should be taken to ensure a sufficient Vitamin D intake.
Intraoperative radiotherapy (Intrabeam): The experiences were presented of 2232 patients in 28 centres (in Switzerland the University Women’s Hospital in Zurich and the Seefeld Breast Centre took part in this study) over an observation period of 4 years. The results are very encouraging, since the group which received one-off radiation during surgery suffered no more local recurrences than those who underwent a conventional 6-week external radiotherapy course. There are still certain reservations here, however, because in this case too, long-term results must first be studied.
In a general sense, it is possible to say that the St Gallen Conference once again brought much good news for those affected by breast cancer, and the more than 4000 participants were able to return home with many good new ideas for the treatment of these patients.