Al-Azhar Assiut Medical Journal

: 2016  |  Volume : 14  |  Issue : 1  |  Page : 33--36

BMI and breast cancer in upper Egypt

Abeer F Amin 
 Department of Oncology, Assiut University Hospital, Assiut, Egypt

Correspondence Address:
Abeer F Amin
Department of Oncology, Assiut University Hospital, Assiut


Background and aim BMI may be an important factor affecting breast cancer outcome. Materials and methods The present study included 100 patients who were newly diagnosed with breast cancer at Assiut University Hospital. Their BMI was measured, and the relation of BMI to the stage of breast cancer and age was determined. Results Patients' ages ranged from 27.0 to 72.0 years. Overall, 45% of the patients were between the ages of 50 and 60 years, and their mean age was 50.6 years. Stage I, II, III, and IV breast cancer were diagnosed in 14, 64, 12, and 10% of the patients, respectively. Around 29% of the patients were overweight and 35% of them were obese. There was a significant positive correlation between age and BMI (P = 0.000). In addition, there was a significant positive relation between BMI and the stage of breast cancer at diagnosis, with a statistical significant difference (P < 0.05). Conclusion Overweight and obese breast cancer patients were more often older, and this was significantly associated with later stages at diagnosis.

How to cite this article:
Amin AF. BMI and breast cancer in upper Egypt.Al-Azhar Assiut Med J 2016;14:33-36

How to cite this URL:
Amin AF. BMI and breast cancer in upper Egypt. Al-Azhar Assiut Med J [serial online] 2016 [cited 2019 Sep 22 ];14:33-36
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Full Text


BMI is used to define body weight status (normal, overweight, and obese). BMI is calculated as body weight in kilograms divided by the height in meters squared (kg/m 2). For people aged 20 years and older, weight status categories are defined as follows:

Obesity is one of the major public health burdens in the world. The WHO stated that overweight and obesity are the most important of the known avoidable causes of cancer after tobacco consumption [1]. According to a study in the prestigious British medical journal, The Lancet, Egypt is the seventh most overweight country in the world. Obesity may increase incidence of various human cancers, as reported in different epidemiological studies [2]. Breast cancer is the most common and the leading cause of death because of cancer among women worldwide [3].

Several studies have reported that menopausal women who are overweight or obese have a higher risk for breast cancer [3–5]. Many epidemiological studies have shown evidence suggesting that a higher BMI is positively associated with an increased breast cancer risk in postmenopausal women [6], but is conversely reduced in premenopausal women [7],[8]. Women who are overweight or obese after menopause have a 30–60% higher risk for breast cancer compared with those who are lean [9].

Obesity increases the risk for cancer by increasing the levels of hormones such as estrogen and insulin [1],[10]. In early life, estrogen is mainly produced in woman's ovaries, but after menopause, fat in the body becomes the main source of estrogen, and so obese women have up to twice as much estrogen as women with a healthy weight; in addition, they have lower levels of 'sex hormone binding globulin', which mops up estrogen in the body [11].

Women who are overweight and obese tend to have higher levels of insulin compared with lean women [12]. Postmenopausal women with high levels of insulin, including women with type 2 diabetes, have shown an increased risk for breast cancer [13]. Any possible link between insulin levels and breast cancer risk are less clear among premenopausal women [14].

In one large study, women who had lost four to 11 pounds after menopause had more than 20% lower risk for breast cancer compared with women whose weight did not change [15], but not all studies showed this result [16].

Treatment outcome and the impact of BMI have been reported in patients with breast cancer receiving endocrine therapy in several studies. These studies demonstrated that the efficacy of aromatase inhibitors vary with BMI but the efficacy of tamoxifen is not BMI-dependent [17].

 Materials and methods

This prospective, randomized study included 100 newly diagnosed breast cancer patients in Assiut University Hospital between August 2013 and August 2014. Data of all patients were analyzed as regards their age, body height, and weight; BMI was calculated and correlated with the stage of breast cancer and age at diagnosis. We considered a woman postmenopausal if she had experienced a final menstrual period of greater than 12 months and had not undergone hormonal therapy before or during this interval. On the other hand, women were considered premenopausal if they were still menstruating and had not taken any hormone therapy during the 12 months before the reference date.

Data analysis

The relationship of BMI to the stage of breast cancer at diagnosis was evaluated using the χ2-test for frequency tables of BMI by stage of breast cancer. The Pearson correlation test was used to determine any association between BMI and age.


In total, 100 newly diagnosed breast cancer patients (age range = 27.0–72.0 years) were included in the present study. We classified them into three age groups: women less than 50 years of age (36% of patients); women equal to or greater than 50 but less than 60 years of age (45% of the patients); and those greater than or equal to 60 years of age (19% of the patients). Their mean ± SD age was 50.61 ± 9.87 years [Table 1]. As regards the staging of breast cancer, according to AJCC staging, stage I, II, III, and IV breast cancer were found in 14, 64, 12, and 10% of the patients, respectively ([Figure 1]).{Table 1}{Figure 1}

They were classified according to BMI into three groups as follows: normal (36% of the patients), overweight (29% of the patients), and obese (35% of the patients) ([Figure 2] and [Table 2]).{Table 2}{Figure 2}

As regards BMI in different age groups, in the group comprising women aged less than 50 years, the incidence of obesity was 22% and the incidence of overweight was 44%; in the group comprising women aged 50 or above but less than 60, the incidence of obesity was 31% and the incidence of overweight was 29%; and in the group comprising women aged greater than or equal to 60 years, the incidence of obesity was 0% and the incidence of overweight was 68%, with a significant P value (P = 0.002*) [Table 3].{Table 3}

Using the χ2-test to compare BMI in different stage groups of breast cancer, there was a significant difference with higher percentage of overweight and obese in fall in late stage group with a statistical significant difference (P < 0.05) [Table 4].{Table 4}


In our study, overweight and obesity were significantly associated with the later stages of breast cancer at diagnosis (III, IV). This may be because of little likelihood of obese women participating in screening [18],[19]; in addition, the increased adipose tissue in obese women may affect early breast cancer detection or may have a biological effect on cancer growth [20].

Obese and overweight women with breast cancer in our study were more often older, with a significant P value (P = 0.002*), which is in agreement with the fact that an excess of adipose tissue in postmenopausal women may elevate the production of endogenous estrogen through the increased activity of enzymes aromatase and 17β-hydroxysteroid dehydrogenase. In addition, a decrease in the sex-hormone-binding globulin, caused by obesity and as a result increased formation of estrone and testosterone may finally promote cellular proliferation and inhibit apoptosis in the breast [21].


Overweight and obese patients in the present study were more often older, and this was significantly associated with the later stages of breast cancer at diagnosis.

Therefore, keeping weight gain in check may be an important public health strategy for reducing the risk for breast cancer in postmenopausal woman, which could be encouraged through health education programs on obesity and breast cancer in the future.

Financial support and sponsorship


Conflicts of interest

There are no conflicts of interest.


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