Age Interactions in Breast Cancer: An Analysis of a 10-Year Multicentre Study in China

Breast Cancer Disparities: A Multicenter Comparison of Tumor Diagnosis, Characteristics, and Surgical Treatment in China and the U.S

BACKGROUND AND OBJECTIVE

Incidence of and mortality rates for breast cancer continue to rise in the People's Republic of China. The purpose of this study was to analyze differences in characteristics of breast malignancies between China and the U.S.

METHODS

Data from 384,262 breast cancer patients registered in the U.S. Surveillance, Epidemiology, and End Results (SEER) program from 2000 to 2010 were compared with 4,211 Chinese breast cancer patients registered in a Chinese database from 1999 to 2008. Outcomes included age, race, histology, tumor and node staging, laterality, surgical treatment method, and reconstruction. The Pearson chi-square and Fisher's exact tests were used to compare rates.

RESULTS

Infiltrating ductal carcinoma was the most common type of malignancy in the U.S. and China. The mean number of positive lymph nodes was higher in China (2.59 vs. 1.31, p < .001). Stage at diagnosis was higher in China (stage IIA vs. I, p < .001). Mean size of tumor at diagnosis was higher in China (32.63 vs. 21.57 mm). Mean age at diagnosis was lower in China (48.28 vs. 61.29 years, p < .001). Moreover, 2.0% of U.S. women underwent radical mastectomy compared with 12.5% in China, and 0.02% in China underwent reconstructive surgery.

CONCLUSION

Chinese women were diagnosed at younger ages with higher stage and larger tumors and underwent more aggressive surgical treatment. Prospective trials should be conducted to address screening, surgical, and tumor discrepancies between China and the U.S.

IMPLICATIONS FOR PRACTICE

Breast cancer patients in China are diagnosed at later stages than those in America, which might contribute to different clinical management and lower 5-year survival rate. This phenomenon suggests that an earlier detection and treatment program should be widely implemented in China. By comparing the characteristics of Chinese and Chinese-American patients, we found significant differences in tumor size, lymph nodes metastasis, and age at diagnosis. These consequences indicated that patients with similar genetic backgrounds may have different prognoses due to the influence of environment and social economic determinates.

Risk factors and natural history of breast cancer in younger Chinese women

AIM: To investigate the age differences in the risk factors, clinicopathological characteristics and patterns of treatment of female breast cancer patients.

METHODS: Seven thousand one hundred and fifty-two women with primary breast cancer from the Hong Kong Breast Cancer Registry were recruited after receiving patients’ consent, they were asked to complete standardized questionnaires which captured their sociodemographic characteristics and risk factors associated with breast cancer development. Among them, clinicopathological data and patterns of treatment were further collected from medical records of 5523 patients with invasive breast cancers. Patients were divided into two groups according to the age at diagnosis: younger (< 40 years old) vs older patients (≥ 40 years old) for subsequent analyses.

RESULTS: Analysis on the sociodemographic characteristics and exposure to risk factors were performed on 7152 women with primary breast cancer and the results revealed that younger patients were more likely to have unhealthy lifestyles; these include a lack of exercise (85.4% vs 73.2%, P < 0.001), having high stress in life (46.1% vs 35.5%, P < 0.001), having dairy/meat-rich diets (20.2% vs 12.9%, P < 0.001), having alcohol drinking habit (7.7% vs 5.2%, P = 0.002). Younger patients were also more likely to have hormone-related risk factors including nulliparity (43.3% vs 17.8%, P < 0.001) and an early age at menarche (20.7% vs 13.2%, P < 0.001). Analyses on clinicopathological characteristics and patterns of treatment were performed on 5523 women diagnosed with invasive breast cancer. The invasive tumours in younger patients showed more aggressive pathological features such as having a higher percentage of grade 3 histology (45.7% vs 36.5%, P < 0.001), having a higher proportion of tumours with lymphovascular invasion (39.6% vs 33.2%, P = 0.003), and having multifocal disease (15.7% vs 10.3%, P < 0.001); they received different patterns of treatment than their older counterparts.

CONCLUSION: Younger patients in Hong Kong are more likely to encounter risk factors associated with breast cancer development and have more aggressive tumours than their older counterparts.

Two modified surgical procedures for treating early stage breast cancer in China

Conventional pedicled-flap based surgeries in treating breast cancer have their limitations. New surgical regimens are yet to be explored, which will follow the oncological principle of being "total tumor free", whilst fit into the unique characteristics of China's own medical system as well as patients' demand. From 2007 to 2013, 143 patients with early stage breast cancer were included in the study, with the average age of 46.1 years. Fifty-three patients were subjected to modified breast conserving surgery (MBCS)+latissimus dorsi (LD) flap reconstruction, 41 to skin sparing mastectomy (SSM)+implant+LD flap reconstruction, 29 to MBCS+distal transverse rectus abdominis myocutaneous (DTRAM) flap reconstruction, and 20 to SSM+DTRAM flap reconstruction. The results showed that out of the 143 patients, there was no graft loss. Minor complications included 4 cases of fat liquefaction, and 6 cases of seratoma, which all resolved after conservative treatment. Five patients had visible protuberance in the abdomen, but not leading to any gastrointestinal symptoms. The reconstructed breasts all presented good shape. 96.7% of the patients were satisfied with the outcome. The follow-up period varied from 6 months to 60 months, and only one patient died from tumor metastasis in the brain. No local recurrence occurred. It was concluded that these two modified pedicled-flap surgeries are readily practical, and aesthetically satisfactory, with high applicability in China. They do not compromise the oncological outcomes, but also are well-accepted by Chinese patients.