An article published early online and in the December edition of The Lancet Oncology reports that if breast cancer patients who receive endocrine treatment develop hot flushes, vasomotor symptoms (such as cold and night sweats), and joint symptoms, then they have a lower likelihood of cancer recurrence. That is, the toxicity of the treatment is acting as an indicator of treatment success.
Professor Jack Cuzick (Cancer Research UK and Queen Mary School of Medicine and Dentistry, London, UK) and colleagues say that the above symptoms during endocrine treatment are related to estrogen depletion or estrogen blockage.
Their analysis used data on women who participated in the Arimidex, Tamoxifen, Alone or in Combination (ATAC) trial, a study designed to assess tamoxifen or anastrozole for adjuvant therapy of post-menopausal breast cancer. To test for a relationship between the toxicity symptoms and cancer recurrence, the researchers compared two groups of women with hormone-receptor-positive tumors: one group reported symptoms at their first follow-up visit in the ATAC trial, and the second group did not report symptoms.
After three months of treatment, 37.5% of eligible women reported new vasomotor symptoms. These women had a 9-year cancer recurrence rate of 23%, while women without new vasomotor symptoms had a recurrence rate of 18%. The 31.4% of women who reported new joint symptoms after three months of treatment had a 9-year cancer recurrence rate of 14%, while those without joint symptoms had a 23% recurrence rate. Women who received both tamoxifen and anastrozole exhibited these rate differences, and anastrozole was linked to lower recurrence rates than tamoxifen independent of the presence of symptoms.
“The appearance of new vasomotor symptoms or joint symptoms within the first 3 months is a useful biomarker, suggesting a greater response to endocrine treatment compared with women without these symptoms. Awareness of the relation between early treatment-emergent symptoms and beneficial response to therapy might be useful when reassuring patients who present with them, and might help to improve long-term treatment adherence when symptoms cannot be alleviated,” conclude the authors.
Treatment-emergent endocrine symptoms and the risk of breast cancer recurrence: a retrospective analysis of the ATAC trial
Jack Cuzick, Ivana Sestak, David Cella, Lesley Fallowfield, on behalf of the ATAC Trialists’ Group
The Lancet Oncology (2008).
DOI:10.1016/S1470-2045(08)70259-6
Written by: Peter M Crosta