MUNICH – Despite the fact that male breast cancer patients on average are older than their female counterparts, and that…
MUNICH – Despite the fact that male breast cancer patients on average are older than their female counterparts, and that male breast cancer and female breast cancer disease profiles differ in diagnosis, male breast cancer patients seem to respond equally well to the same treatments as those given to women, suggests data from several new studies.
The new analyzes were presented as posters here at the European Society of Medical Oncology (ESMO) 2018 Congress. They were welcomed by experts who pointed out that male breast cancer is a rare disease, for which there is a lack of data both on occurrence and treatment results.
In the first study, Mohamed A. Gouda, MD, Department of Clinical Oncology, Menoufia University, Shebin El Kom, Egypt, examined data from the National Cancer Institute’s Monitoring, Epidemiology, and Final Results Program in all cases of breast cancer reported in USA under 1
5 years (2000-2015).  His team identified 6790 men diagnosed during the study period, with an incidence rate of 10.2 per 100,000,000 men.
Incidents increased significantly during study time, with an annual percentage change of 1.9% ( P <.05).
The majority (81.3%) of cases occurred in white men (median age, 68 years). The cancer was more likely to occur on the left side, at a rate of 52.3%. Most cases were either regional (43.8%) or localized (46.4%) at the time of diagnosis.
Note: Breast cancer was the only primary in 66.3% of patients. It was the first of two primaries in 11.6% of patients; and it was secondary or secondary in 22.1% of patients.
Computation of median survival with the Ederer II method, Gouda found that median observed survival for male breast cancer was 70.6% at 5 years and 48.8% at 10 years. 19659009] Five-year relative survival was estimated at 84.0% and 10 years relative survival was 71.1%.
Given Medscape Medical News Gouda said it is not clear why breast cancer in men should be found more often on the left but he speculated that it may be related to the disease that occurs as a second primary in about one fifth of the cases rather than a phenomenon associated with case reporting.
He added that it “may be a further consequence of previous treatment.”
Gouda stressed that despite differences in baseline characteristics between male and female patients, male breast cancer is treated in the same way we treat female breast cancer. “He added,” According to our knowledge, it has a slightly different course. “
These findings were derived from a major study from France. In that study, the average age and treatment profile was the same for male and female patients.
Jean-Sebastien Frénel, MD, from the Institute of Cancerology de l’Ouest, Nantes, France, and colleagues collected data from the Epidemiological Metastatic Breast Cancer Platform, comprising 18 French-wide cancer centers, for 2008 to 2014.
They identified 149 men (0.89%) of a total of 16 701 evaluable breast cancer patients.
Like the Gouda study, the mean age of male patients was 68.1 years, which was significantly older than for women at 60.6 years ( P <.0001).
Men were also significantly more likely than women to have hormone receptor positive (HR +) and human epidermal growth factor-2 negative (HER2) disease at 78.4% versus 65.6% ( P = .0019).
Among the HR + / HER2-42.9% received the first line hormone treatment, which contained tamoxifen (multiple b rands) or an aromatase inhibitor with or without luteinizing hormone releasing hormone (LNRH) analog.
Median Progression-Free Survival (PFS) among these patients was 9.8 months, which was comparable to that seen in a group of women matched for age, breast cancer histology, breast cancer quality, metastasis site and adjuvant treatment at 13.0 months ( P = .8).
For 27.6% of HR + / HER2 male breast cancer patients treated with first line chemotherapy, median progression-free survival was 6.9 months, which again resembled the 6.3 months seen in a group of matched women.
Median survival was comparable between men and women at 41.8 months and 34.9 months ( P = .745).
“We found that men with HR + / HER2 disease had similar survival results as women with the same type of breast cancer,” Frénel said in a statement.
“Most patients receiving hormone therapy were treated with tamoxifen, and the rest received aromatase inhibitors,” he continued. “However, few patients received aromatase inhibitors plus LHRH analogues, despite some guidelines recommended to be given in combination.”
Commenting on ESMO, Agnes Jager, MD, PhD, from the Erasmus Medical University Cancer Institute, Rotterdam, Netherlands, said such a major study of men with primary breast cancer “was missing so far.”
This justifies our current clinical practice.
“This new study shows that the forecast for men and women is similar, which is of great value, as this justifies our current clinical practice,” she said. “We currently treat men with breast cancer in the same way as women, now supported by these data.”
However, she noted that the study was small and that there was no data on the extent of advanced disease, BRCA mutation status and type of chemotherapy used.
“More detailed information and long-term follow-up will indicate whether there are attributes or prognostic factors specific to men, which will allow us to change exercise in the future,” she added.
The Male-GBG54 study, the first prospective randomized study to investigate various hormonal treatments in breast cancer men, Mattea Reinisch, MD, PhD, from Essen-Mitte, Essen, Germany and colleagues compared tamoxifen with or without a gonadotropin releasing hormone analogue (GnRHa) with an aromatase inhibitor plus a GnRHa.
For the study, 55 men with breast cancer with HR + disease were randomly assigned to receive one of three regimes for 6 months:
Among the 46 men for whom complete data were available, those treated with tamoxifen experienced an increase in oestradiol levels of 67% at 3 months and 41% at 6 months.
On the other hand, estradiol levels fell in the two arms where men received hormonal treatment with a GnRH analogue and continued to remain low. The tamoxifen plus GnRHa group experienced a decrease of 85% at 3 months, while those receiving exemestan plus GnRHa experienced a 73% decrease. This continued for 6 months, with a decrease of 59% and 63%, respectively.
Tamoxifen treatment had little effect on health-related quality of life or erectile function. However, both of these measures were seriously affected in patients treated with exemestan + GnRHa, researchers noted.
“The suppression of peripheral estradiol is a necessary condition for a therapeutic benefit of endocrine therapy in men with breast cancer upon receipt of an aromatase inhibitor plus GnRH analogue,” says Reinisch in a press release.
“In tamoxifen monotherapy, estrogen levels increased. These changes are known from female breast cancer patients and were expected,” says Reinisch.
She concluded that “tamoxifen monotherapy should be held as standard hormone treatment for men with breast cancer. The side effects are moderate, hardly impairing sexual behavior.”
“The combination with GnRH affected the well-being and erectile function of the patients deeply.”
ESMO expert Hunter commented that the researchers “congratulated” for performing a randomized study “in such a rare study population, which must have been a real effort.
“However, it is regrettable that oestradiol suppression at 3 months was the primary endpoint,” she said.
“While it is relevant to know if and to what extent ozone levels change over time under different endocrine treatment strategies, as far as I know, oestradiol suppression at 3 months is neither a validated nor clinically useful surrogate endpoint for the effect of endocrine treatment,” she said .
She added that the finding that tamoxifen caused an increase in oestradiol levels at 3 and 6 months “is not new, although the rate of increase is somewhat unexpected.”
In summary, Jager emphasized that the endpoint used in the study means that the issue of an LNRH agonist should be added to keep tamoxifen unresolved.
“Because of the serious side effects of LHRH agonists in men and the negative impact on quality of life, the clarity about this is of great clinical significance,” she said.
Also commenting on ESMO, Stefan Zimmerman, MD, Center Hospitalier Universitaire Vaudois, Switzerland said that the studies together show that “male breast cancer patients seem to benefit from endocrine therapy to the same extent as women.”  “These research findings add to the current literature suggesting that the addition of GnRH analogues can improve on tamoxifen alone, but clinical endpoint studies are needed,” he said in a statement.
However, Zimmerman stressed that “it is urgent that strategies that have proven effective in postponing resistance to endocrine therapy in women are also explored in men with advanced breast cancer, including CDK4 / 6 inhibitors.”
Male The GBG54 study was funded by Claudia von Schilling Foundation and was conducted in collaboration with Pfizer. Dr Gouda, Dr. Frénel and Dr. Reinisch have not disclosed any relevant economic relations.
European Society for Medical Oncology (ESMO) 2018 Congress. Abstracts 259P, 294PD and 273PD, featured October 22, 2018.
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