Of the 362 patients studied, 62 of them were excluded because they refused to sign the consent form (10/62, 16.1%), they had no time to answer the questionnaire (48/62, 77.4%), or there was a prior history of breast resection surgery (4/62, 6.4%). The study group was 300 women with age ranging from 40 to 77 years. Significant differences between the two groups were not observed in obesity degree (Tables and ), age of menarche (≤50: 12.68 ± 1.61; >50: 13.12 ± 1.64,t
-student −2.305, P
= 0.022) tobacco and alcohol consumption, history of oral contraceptive use, history of pregnancies and abortions, lactation history, and familial history of BC (). No woman in the study was classified with abuse problem or alcohol dependency. Less than 20% of women were smoking, with an average of 5 cigarettes per day, ±2.
Body mass index (BMI) in 300 Mexican women.
Distribution of characteristics according to age.
In these women aged 40 years or older, the present study was the first to be performed in 40% of cases. The average age of the first mammogram was 49.9 years, ranging from 40 to 71 years. The decision to seek mammography performed was the idea of the patient at 7% of cases and it was indicated by the physician or a nurse as part of the breast cancer screening program in 93%. There was no difference between the two groups in relation to family history of breast cancer in general, or in first-degree relatives (mother and sisters). As expected, menopause was present in less than 50% of women aged 50 years or younger and in 93% in older women. Women in the north of the country have the highest rate of caesarean sections in Mexico, a phenomenon that has already been detected since several years ago.
shows the distribution of BD patterns according to age. The general distribution of mammographic density in these women according to BI-RADS classification showed a fat pattern in 56.7% of cases, 29% with fibroglandular pattern, 5.7% with heterogeneous pattern, and 8.6% with high density pattern.
Breast density, and age distribution.
shows BD and its relationship to women older and younger than 50 years. Mammographic density was strongly influenced by the age of the patient, with significant difference in younger and older than 50 years. Thus, the distribution of the four patterns, fat, fibroglandular, heterogeneous dense, and dense was 37.6, 36.7, 9.4, and 16.2%, respectively, for women under age 50 and 68.8, 24, 3.3 and 3.8% for women over 50 years.
Breast density in women younger and older than 50 years.
66 women (22%) showed asymmetry in mammographic density. The compression cone ruled out the underlying pathology in 56 cases. In the remaining 10 women, lesions were detected that were confirmed by biopsy. These lesions were diagnosed as fibroadenoma (1 case), complex cyst (1 case), and cancer (8 patients). Of the cancers found, 6 were invasive ductal carcinomas and 2 were intraductal neoplasms. All carcinomas were non-palpable lesions. Cancer was detected in 2.6% of patients in this study. 50% (N = 4) of cancers were found in patients 50 years or younger.
Of the total sample, 190 women (63.3%) had benign lesions that corresponded to vascular calcifications (150 patients), fat necrosis (38 patients), and hamartomas (2 patients). 246 cases (82%) only needed the mammography for diagnosis, whereas in 54 patients (18%) it was necessary to supplement the study with ultrasound.
Mammography identified BI-RADS 1 in 78 patients (26%) of which only one required an additional ultrasonography (US) to define the diagnosis (0.3%); BI-RADS 2 was diagnosed in 190 patients (63.3%) of which the mammography was supplemented with US in 33 patients (11%). BI-RADS 3 was found in 16 patients, 2 hamartomas and 2 fibroadenomas, the remaining 12 patients needed to complement with US, detecting 5 simple cysts, 6 complex cysts and 1 cancer, BI-RADS 4 were 8 cases, and all required US complement; findings included 1 complex cyst, 1 fibroadenoma, and 6 neoplastic tumors.
Cancers detected by both mammography and US were later corroborated by biopsy. Of these, one was BIRAD 3, six had BI-RADS 4, and one was BI-RADS 5. Neoplastic cases were associated with fibroglandular density pattern in 3 cases, 3 had heterogeneous, and 2 high-density patterns. 5 carcinomas were found in 43 patients with high-density pattern (heterogeneous + dense) and 3 neoplasms were detected in 3/257 patients with low-density patterns (fat & fibroglandular) (). shows the BI-RADS diagnosis according to BD patterns. Only dense density pattern in this sample was associated to BI-RADS 0. Also, it had the highest proportion of BI-RADS 3 and 4. The cancer cases were associated to high density in 5 cases (62.5%).
Distribution of mammographic diagnostics (BI-RADS) according to breast densities patterns.