The population based cancer registries of India have shown significant increase in number of breast cancer diagnosed over the years in India . It has been felt by different groups that breast self-examination and clinical examination are perhaps the right tools for early detection of breast cancer for screening the huge population of India, but no credible data is available today to base these views on. Mammography is the investigation of choice for Breast Screening.Breast Screening related information, both potential benefits and possible risks, must be given to the lady and mammography must be performed after the lady gives an informed consent.
There are many screening guidelines from countries that have a population based breast screening programme. These programmes vary from country to country and hence there are different guidelines from different Breast Societies in the world.
Due to lack of data specific to our country,currently no specific guidelines are available in India. However a few concepts and facts are recognised all over the world and these can be applied to the Indian population in general.
There are other facts that are specific to our country, such as increasing incidence of breast cancer in younger women, and the practice in India needs to be planned keeping these in mind. Some examples of Breast Screening Programme/ guidelines are The National Health Service BreastScreening Programme (UK) and American College of Radiology Guidelines .
For women at average risk of breast cancer, screening mammography is recommended between ages of 50 and 74 years . Mammography screenings are effective and generate a 17% reduction in breast cancer mortality in women 39-49 years of age . Because breast cancer incidence increases with age, more women among the younger age group (40-50) will need to be screened for each life saved than for women 50 years of age or older. However, because younger women have a longer life expectancy, life years gained for the women diagnosed with breast cancer by screening in their 40s is higher than in the 50- to 70-year-old population . There is no evidence of mortality benefit from mammography screening of women under the age of 35 years . There is greater risk of radiation induced breast cancer from the use of X-Ray mammography in young women .
Patients presenting with breast cancer are about one decade younger in developing countries than their counterparts in developed nations. The proportions of young patients (< 35 years) vary from about10% in developed to up to 25% in developing Asian countries, which carry a poorer prognosis .
In the developing countries, the majority of breast cancer patients continue to be diagnosed at a relatively late stage, and locally advanced cancers constitute over 50% of all patients managed .There is no upper age limit established for screening mammography, but as the benefits of screening mammography may take years to be fully realized, screening recommendations should take into account life expectancy and comorbid conditions, with screening mammography remaining
appropriate when a woman’s life expectancy exceeds 5 to 7 years.
BREAST SCREENING RECOMMENDATION FROM BREAST IMAGING SOCIETY, INDIA:
Taking all of the above data into consideration, 40 years is recommended as the age for starting Mammography based screening in India. Although no dedicated population based screening programme exists in India, opportunistic screening of interested women, on a yearly basis, from the age of 40 years, is deemed appropriate. Annual mammography is advised till the age of 70 years.
Beyond the age of 70 years, it is advised that a decision is made based on lady’s comorbidities and life expectancy.
Screening (Surveillance) of contralateral breast to look for metachronous breast cancer after unilateral mastectomy for breast cancer is to be performed under the age of 40 years, if cancer was detected earlier than this.
Ultrasound and MRI may be required as adjuncts as women less than 35years of age may have rather dense breasts.
High Risk Group Screening (mammograms along with Breast MRI) is appropriate if there is a lifetime risk of breast cancer of about 20% to 25% or greater, according to risk assessment tools that are mainly based on family history, if lady has a known BRCA1 or BRCA2 gene mutation or has a first degree relative with BRCA1 or BRCA2 gene mutation (and has not had genetic testing herself), has had radiation therapy to the chest when she was between the ages of 10 years and 30 years .
Screening with annual mammography (and annual MRI) is recommended to begin at age 30 years or10 years before age of first-degree relative with breast cancer, whichever is later.
With history of mantle radiotherapy, annual mammogram (and annual MRI) should be started 8 years after radiation therapy, but not before age of 25 years. Mammography and MRI are complementary examinations, and both should be performed .