Ex. Chief Scientist, Rural Development Coordinator, and Project Advisor, CSIR-CFTRI, Mysore talks about the latest trend of breast cancer and its research in India. She is the recipient of several awards like Abdul Kalam Life Time Achievment Award, Kissan Ratna Puraskar, and Nari Shakti award.
On breast cancer status and trends in India
Breast cancer is the leading carcinoma in India, surpassing that of cervical in the last decade. The mortality rate due to breast carcinomas is increasing day by day, mostly because of inadequate screening tests and diagnosis at an advanced stage. The worrisome situation is its occurrence in premenopausal women, where the dense breast tissues make screening difficult, leading to the false negativity of presence of malignant palpable mass. In a survey, breast cancer has been ranked number one cancer among Indian women with the occurrence of 25.8 per 100,000 women and mortality rate of 12.7. Data reports from various national cancer registries were compared for incidence and mortality rates. Mortality‐to‐incidence ratio was found to be alarmingly high at 66 in rural registries and that of 8 in urban registries. The somatic alteration in TP53 gene is considered as one of the major causative agent. The survey finds that it has become an epidemic due to lack of both inadequate awareness and early diagnosis.
On causes of the disease
The reasons cited for this disease include exposure to ionizing radiation, hormone replacement therapy, obesity, and consumption of alcohol. Some reports also indicate its direct correlation with early menarche (onset of menstruation), late or no childbirth, and family history. The occurrence of around 5-10% of breast cancers is attributed to the genetic predisposition, infertility, and hormonal imbalance. Sometimes, over consumption of birth control pills play a major role in stimulating abnormal growth that may lead to breast cancer. Commonly, the cancer develops from the lining of milk ducts and the milk supplying lobules termed as ductal carcinomas and lobular carcinomas, respectively. Sometimes, they may metastasize and spread to other parts of the body.
On breast cancer research
Earlier reports suggested that the majority of breast tumours from Asian women are estrogen receptor (ER) negative. However, in the last decade, it has been established that both pre- and postmenopausal affected Asian women are likely to have ER positive tumours, similar to the Caucasians. A sensitive and specific hormone receptor testing has immediate and direct clinical implications, as false negative reports can result in the under utilisation of highly efficacious endocrine treatments. DNA microarray studies have been one of the latest technologies for identifying breast cancer subtypes that reflect biologically distinct disease entities. Recent studies suggest that targeting the hormonal pathway may be very relevant in managing breast cancer in many populations across the spectrum.
On new and emerging research areas
Patients undergoing medications like selective estrogen and progesterone modulator, and mastectomy (removal of breasts) which are recommended to women with higher risk of metastasis may reduce the risks of breast cancer but increases the risk of thromboembolism and endometrial cancer. A few reports suggest that use of oral contraceptives may cause premenopausal breast cancer. Sometimes exposure to estrogen may trigger hereditary breast-ovarian cancer (HBOC) syndrome. If fibrocystic changes take place in benign conditions, it may also cause the disease. Over expression of leptin also leads to increased cell proliferation and cancer. TP53 mutation has been identified as a reason behind 40-60% of breast and ovarian cancers. However, individual variations may arise due to DNA methylation. Due to this mutation, it has been observed that both breast and ovarian cancers occur simultaneously.
In ductal carcinoma in situ (DCIS), the abnormal cells are found to be present in the milk duct, which sometimes turns into invasive breast cancer. Scientists are studying various statistical methods to estimate the parameters of DCIS becoming invasive. In another approach, decision aids are being designed and developed for woman to help them decide any particular factor that might be important in choosing a treatment. The malignant breast cells metastasize by entering blood vessels. These circulating tumour cells (CTCs) can be detected by high-end molecular predictive tests and used for detection of metastasis. Newer imaging techniques have been developed to evaluate the changes taking place in the breast wherein a radioactive drug is injected into a vein called a tracer that attaches at the breast cancer cells.
On prevention methods
Increased breastfeeding and physical activity are protective for both ER-positive and ER-negative breast cancers. It is possible to prevent the disease up to an extent by maintaining a healthy weight, reducing alcohol intake, exercising and breast-feeding. It has been found that eating citrus fruits, omega-3 polyunsaturated fatty acids and soy-based foods also reduce the risk. A high dietary intake of calcium showed 33% lower risk of breast cancer. Vitamin D is also known to reduce the risk of breast cancer.
On treatment trends
Triple negative breast cancers, a diagnostic test to establish line of treatment and based on presence of three markers, namely estrogen receptor (ER), progesterone receptor (PR), and human epidermal growth factor receptor 2 (HER2), can neither be treated with hormone therapy nor with targeted therapy. Therefore, these patients need to undergo chemotherapy. Other potential new breast cancers drugs like kinase inhibitors are helpful in treating these subtypes. Targeted therapy drugs specifically target the genes responsible for modification in cancer cells like PARP inhibitors. These drugs are helpful against cancers caused by BRCA gene mutations. Olaparib (Lynparza) is now being used to treat women with BRCA mutations who have metastasized, and HER2-negative breast cancers.
Some breast cancers require estrogens to continue growing. These ER+ cancers, one of three subtypes based on treamnet line, can be treated with drugs that block the estrogen receptors like aromatase inhibitors. These inhibitors are suitable for postmenopausal breast cancers, and not given to premenopausal women with intact ovarian function. Breast reconstruction surgery, option available for patients who have undergone mastectomy, is possible by plastic surgery. Neoadjuvant therapy, like chemotherapy, is defined as the first step treatment administered to shrink the tumor, before mainline treatment like surgery. Aspirins are known to reduce mortality rate. Chemotherapy is used for second to fourth grade carcinomas, which are usually given in combinations for 3-6 months. Radiotherapy, given after surgery to the region of the tumour and regional lymph nodes, destroys the microscopic tumour cells that might still be present even after the surgery.
On areas that are being neglected and need attention
The most important resource in cancer epidemiology is accurate reporting and completeness of incidence and mortality data. Comprehensive data collection and administration is a necessary component of developing and planning cancer control initiatives, appropriate allocation of resources and prioritization of cancer health policies. The lack of reliable and complete census data often presents a particular challenge in low and middle-income countries. Therefore attention on organized awareness programs, preventive measures, and screening programs for early detection and availability of treatment facilities are essential for reducing both incidence and mortality in Indian women.
On how to bring more awareness in rural India
The Accredited Social Health Activists (ASHAs), schools and colleges might be the most effective apparatus to bring in awareness. The health professionals need organized training/education to fill the knowledge gap. There is a pressing need to explore ambassadors to fill the fissure of awareness deficits and social stigma surrounding breast cancer. Understanding the barriers is vital for strategic and effective awareness campaigns and/or interventions on prevention and early detection. Low awareness scenario is also attributed to poor coverage in the media, where the publicity and policy efforts on cancer have primarily been focused on the reduction and perils of tobacco usage. Indian women need to be aware regarding the risk factors for improved hygiene and healthcare. Priority should be given to effective cancer literacy programmes from community to national level. Continuing medical education (CME) programmes with enhanced emphasis on breast cancer in the curricula of nursing at institutional level and other healthcare training institutions should be given precedence to bring about awareness among the women for self-examination of breasts and routine screening tests like mammography.