Obstacles to early breast cancer detection
In LMCs, worsened cancer survival is largely attributable to late stage presentation, which leads to particularly poor outcome when coupled with limited diagnostic and treatment capacity. Of the over 75,000 new breast cancer cases presenting for treatment each year in India, between 50% and 70% have locally advanced disease at diagnosis. By comparison, 38% of European and only 30% of American breast cancer cases were reported to be lymph-node positive or locally advanced at diagnosis (T1-3N+M0 or T4NxM0), in the EUROCARE study and SEER cancer registry between the years 1990 and 1992. Thus, the determination of which factors promote or inhibit women’s participation in early detection programs becomes highly relevant to the relative success of a population-based cancer strategy.
Social or cultural issues may also adversely impact women’s participation in early detection programs, and failure to anticipate these inhibitory factors can adversely affect research or clinical outcomes. For example, a large population-based randomized trial studying screening clinical breast examination (CBE) in the Philippines could not be completed, because over 60% of women from this relatively well-educated population in Manila refused to complete the required follow-up diagnostic studies once a finding on CBE was identified. The researchers concluded that cultural and logistic barriers to seeking diagnosis and treatment must be addressed before any screening program is introduced.
Azaiza and colleagues have provided an important analysis of screening behaviors in relation to cultural and environmental barriers among women who live in the Palestinian Authority. This highly relevant study found that women in this region of the Middle East were more likely to undergo screening mammography if they were (1) less religious, (2) described as having fewer personal barriers to examinations, and (3) indicated a lower degree of cancer fatalism. Cancer fatalism is a problematic social belief system suggesting that cancer occurs as a result of predetermined destiny, which could lead one to believe that the course of disease is not likely something that one could personally influence or prevent. Women who consented to CBE had a higher perceived effectiveness of CBE and described lower levels of cancer fatalism. Muslim women were half as likely as were Christian women to participate in CBE screening. Similarly to women who underwent CBE, women were more likely to perform self-breast examination (SBE) if they were more highly educated, resided in cities, were Christian, and were less religious. Also, women with a first-degree relative with breast cancer were more likely to practice SBE.
Fatalism can create a very significant obstacle for participation in early detection programs. Since participation in an early detection program depends upon a person’s acceptance that early intervention can favorably influence one’s destiny, a person who has strong fatalistic beliefs may be unlikely to accept that early detection approaches could work. The Azaiza study of women from the Palestinian Authority suggests that fatalistic belief systems may be more common among people who consider themselves to be more religious. One approach to improved participation in breast cancer screening might be to recruit church or religious leaders as spokespersons for early detection messages. Additionally, when religious practices require women to remain completely covered, as is the case in many Muslim countries, women may feel that SBE and CBE are unacceptable or shameful practices. Special screening clinics staffed by women physicians and nurses and adapted to the needs of specific religious communities may be required to promote screening participation in these regions of the world.
Early Breast Cancer Detection in the Absence of Screening Mammography
The value of BSE as a screening tool in LMCs remains an area of controversy. Some groups have concluded that self-examination has no benefit in improving breast cancer outcome, based primarily on the negative BSE randomized trial performed in Shanghai, China and reported in October 2002. The cluster randomized trial assigned 260 factories to the instruction group and 259 factories to the control group. All current or retired female employees ages 30 – 65 years of age were eligible for study. Women from the instruction factories were given intensive instruction in BSE, reinforcement sessions one and three years later, and practiced BSE under the supervision of a factor medical worker every six months for five years. Women in the control group may have been performing BSE on their own recognizance, but they received no formal training in the process. Because no mortality difference was seen between the groups trained in SBE versus those that were not, many concluded that BSE is not of clinical value. In fact, the Shanghai study data does not support this sweeping conclusion.
Generally overlooked from the Shanghai BSE trial is the fact that even the women in the control group of this study performed BSE quite effectively despite the lack of formal training. Over 40% of the breast cancers diagnosed in the Shanghai control group were less than 2cm in diameter, suggesting that Chinese women appear to do well with breast cancer early detection without the assistance of training in BSE methodology. These statistics stand in strong contrast to cancer demographics from the Middle East, Africa, and India where the median tumor size is commonly 4-6 cm at presentation, the majority of women presenting with locally advanced or metastatic breast disease at initial diagnosis. The differences in cancer presentation between women from these regions of the world compared to China are not fully understood, but could relate to different cultural beliefs. While not formally studied, it is reasonable to hypothesize that women who are taught that exposing their bodies is socially improper and are discouraged from touching or examining their own breasts would be at significant disadvantage for self-identification of disease.
Preliminary results from a new cluster randomized trial suggests that CBE in fact facilitates the down-staging of breast cancer in Mumbai, India where women commonly present with advanced stage disease at diagnosis. Women in the intervention group underwent CBE for detection of breast abnormalities and also underwent cervical inspection for plaque or lesions warranting cryotherapy. For comparison, women in the control group received health education alone but did not undergo CBE (or cervical inspection). More than 75,000 women have now been randomized to each arm. Screening among the intervention group is planned to occur every two years for four cycles; women will then be monitored for eight years to determine cancer outcome. In a recent update of the study and after three rounds of screening, more breast cancers have been found in the intervention group (125 cases vs 87 cases in the control group) and of these, a significant fraction were stage 0, I or II at initial diagnosis (62% vs 44% in the control group).
BHGI Learning Laboratories
BHGI has adopted an implementation strategy of developing collaborative relationships with organizations and institutions in LMCs to focus on situation analysis, education and training, and adapted use of affordable technology for breast cancer early detection, diagnosis and treatment. In Kumasi, Ghana, a surgical pathology laboratory has been established through a collaboration established between the University Hospital of North Norway and the Komfo Anokye Teaching Hospital in Kumasi, Ghana during the 2nd BHGI Global Summit in 2005. Since then, BHGI has coordinated two professional training courses in Ghana (January 2010, Kumasi; August 2010, Accra), targeting the educational needs of physicians, nurses and breast cancer advocates. Future projects are underway in other countries including a cluster randomized screening trial in Bogota, Colombia. The International Atomic Energy Agency (IAEA) has established a formal relationship with BHGI to create training courses in other partnership countries, modeled after the courses taught in Ghana. BHGI intends to develop models that can be generalized and translated to other environments of similar economic and health care resources.
Relevance to High-Resource Countries
The improvements in breast cancer survival in the industrialized world seen in recent decades can be attributed to early detection by screening, combined with timely and effective treatment as guided by the results of extensive and rigorous clinical trials. Randomized trials using screening mammography with CBE initiated in the 1970s showed that early cancer detection within a given population leads to down-staging of disease and improvement in breast cancer survival. At the same time, randomized trials of systemic therapies for breast cancer proved that endocrine therapy for estrogen-receptor positive (ER+) cancers and cytotoxic chemotherapy for ER–cancers improves survival and durable long-term cure among lymph node negative, lymph node positive, and even locally advanced breast cancers. Breast cancer mortality, which had been essentially unchanged in the U.S. for the six decades between the 1930s through the 1980s, has been dropping by nearly 2% each year between 1990 through the present.
Research performed in LMCs also applies to care for underserved populations in the United States. Notably, minority women in the U.S. are more likely to present with advanced stage disease and have higher mortality rates than do white women, although white and black women presenting with similar-stage disease and receiving similar treatment have similar outcomes. These findings suggest that differences in stage at presentation should represent primary targets for research, the goal of which is to determine which interventions best reduce disparities in cancer outcomes among women from different social or racial groups.
Improving breast cancer outcomes in LMCs will require concerted efforts to provide resource-adapted solutions for breast cancer early detection, diagnosis, and treatment, applying what has been learned and successfully applied in high-resource environments in these settings where significant infrastructure components are missing, early detection strategies for cancer have not been employed, and significant social or cultural obstacles may impede progress. The BHGI is working to collaborate with colleagues in LMCs to develop practical strategies to improve outcome, applying implementation research methodology to promote early detection strategies in settings where appropriate care can be administered.
Financial Disclosure: The author has no significant financial interests or other relationships with the manufacturers of any products or providers of any service mentioned in this article.