Types of breast cancer and ways to treat them
Understanding breast cancer
According to a recent report by the Indian Council of Medical Research (ICMR) and National Centre for Disease Informatics & Research (NCDIR), breast cancer will be the most common cancer in women in India (an estimated 2.0 lakhs or 14.8% of all cancers) in 2020. It is the most common invasive cancer in women and the second leading cause of cancer related deaths after lung cancer. Breast cancer forms in the lobules or ducts of the breast. It can also occur in the fatty tissue or the fibrous connective tissue within the breast. The cancer can spread outside the breast through blood and lymph vessels. Factors such as rise in sedentary lifestyles, smoking, obesity, consumption of alcohol and genetics have contributed to the increasing incidence of this disease. Therefore, awareness about breast cancer and its types is crucial for seeking the right treatment within the right time for combating the disease burden.
Types of breast cancer
Breast cancer can be categorized as ‘invasive’, ‘non-invasive’ or ‘in-situ’. While invasive breast cancer spreads from the breast ducts or glands to other parts of the breast, non-invasive breast cancer does not spread from the original tissue. In situ refers to a group of abnormal cells that are found only in the place where they first formed (in case of breast cancer, it would be the breast).
Following are the different types of breast cancer based on the above categories and ways to treat them:
I. Invasive Ductal Carcinoma (IDC): This is the most common type of breast cancer where the abnormal cells that start forming in the milk ducts spread into other parts of the breast tissue. According to John Hopkins Medicine, IDC forms nearly 80 per cent of all breast cancer diagnoses.
Treatment: The treatment for DCIS depends upon the exact type and staging of the cancer. Depending upon the type of tumour, one can undergo a mastectomy, lumpectomy with or without oncoplastic or reconstructive surgery, sentinel node biopsy (this helps in detecting the spread of the cancer to the lymph nodes by removing them surgically for testing), radiotherapy or chemotherapy. In certain cases, a combination of treatments may also be administered.
II. Ductal carcinoma in situ (DCIS): This is a non-invasive cancer where abnormal cells are detected in the lining of the breast milk duct. It is non-invasive because the atypical or abnormal cells do not spread outside the ducts into the surrounding tissues. DCIS is an early stage cancer which can be treated when detected on time. However, when left undetected or untreated, it can spread to the surrounding tissues.
Treatment: DCIS can be treated through breast-conserving surgery (lumpectomy) and radiation therapy or breast-removing surgery (mastectomy). In case of lumpectomy, the area of DCIS and a margin of healthy tissue that surrounds it is surgically removed, helping in restoring the breast as much as possible. In mastectomy, the whole breast tissue is removed for treating the cancer and one can opt for a breast reconstruction surgery at a later stage to restore their appearance.
III. Inflammatory breast cancer (IBC): This is a rare cancer in which the cancer cells block the lymph vessels in the skin of the breast. It is called inflammatory because the breast looks swollen, red and inflamed in this case. Most IBCs are invasive ductal carcinomas and they develop from cells that line the milk ducts and then spread further. IBC is considered as Stage 3 or Stage 4 cancer.
Treatment: IBS is treated through a multi-modal approach, first with systemic chemotherapy to help shrink the tumour, followed by surgery to remove the tumour and finally radiation therapy. The treatment procedures include neoadjuvant chemotherapy administered ahead of surgery, targeted therapy, hormone therapy, radiation therapy, surgery and adjuvant therapy (administered after surgery to reduce the chance of cancer recurrence).
IV. Special type of carcinomas: These are a mixed group of cancers of breast i.e. invasive lobular carcinoma, tubular carcinoma, medullary carcinoma and mucinous carcinoma
Treatment: The treatment is on the lines of any other invasive ductal carcinoma. Although they are a heterogeneous group, and prognosis varies as per various biopsy features, in general they have a better outcome than invasive ductal carcinomas.
