Cancer cure linked to menstrual cycle

Press, 13 April 1988, Page 42

Cancer cure linked to menstrual cycle

NZPA Florida A woman’s chance of being cured by breast cancer surgery may depend on the point in her menstrual cycle at which surgery is performed, a study of mice suggests. ’ The study said researchers doubled the j breast rate in mice by removing the tumour at the right time in the mouse menstrual cycle. “Within a few years we may know if this is true in human beings,” said William Hrushesky, of the University of Minnesota. “The goal would be to, define just what creates any such advantage in people, and to use drugs to simulate it during surgery,” he said. The experiment focused on the 5.5-day mouse estrous cycle, which corresponds to the monthly menstrual cycle in i women. [ I | , [ Tumours that: grow faster in response to the ; hormone, estrogen, as many human breast tu-j

mours do, were implanted in the mice. Later-analy-sisjshowed the timing of the[ implant in the estrous cycle made no difference in [cure rates. ;; ‘‘But the timing of surgery [to remove the tumdurs markedly influenced the likelihood that would have spread to | the lungs by [ 28 days after [ the operation," Hrushesky said. Sixteen of 60 mice [that underwent surgery ) near the fertility peak of! the cj[cle: were found to be free of lung involvement, ; compared with nine olf 73 [ that had surgery in’ the infertile phase. [“ln human terms,, the highest cure rate J corresponds to surgery [ just befoije and during ovulation, I with- the lowest’ rate ’ corresponding to surgery around menstruation,” Hrushesky said. -!I J [ “The next step iis to examine hospital charts to see [if a similar pattern appears in human breast cancers, and to study women after they have

breast[cancer surgery at known; points in the menstrual cycle,” he [said. Hrushesky also said a chemotherapy schedule tailored to the natural day-long rhythms of the body 'prolonged! survival in! 50 people with cancer that had spread from the kidney. [ i [“That condition has been ‘ considered untreatable with drugs, and half of patients usually die within 5 three to six months,” he said. “But the therapy has reliably produced; remissions of six months to a year and longer.” ! The[ patients received chemotherapy; in a round-the-clock infusion, with the dose peaking every night. That continued for I[4 days, followed by 14 days of no drug before the regimen began again, j Patients could tolerate twice as much drug per week [with the daily varia-’ tion in the infusion rate as they could have with a constant rate, Hrushesky said.