Advancements in Cancer Treatments
Over the last many years, remarkable progress has been made towards understanding of cancer development and treatment.
Treatment modalities comprising of radiation therapy, surgery, chemotherapy and hormonal therapy have advanced further.
Under radiation therapy today we have precision radiation therapy in which a high-energy radiation beam is targeted at diseased cells, preventing damage to neighboring tissues. Some of the techniques today include intensity modulated radiation therapy to treat nearly every type of solid tumor, image guided radiation therapy (e.g. head and neck, prostrate cancers), stereotactic radiotherapy (treatment of early non-small cell lung cancer, prostrate, head and neck, liver, kidney, oligometastases, spinal and pancreatic tumors), stereotactic radiosurgery using CyberKnife to treat small deep brain tumors (other cancers that can be treated include breast, kidney, liver, lung, pancreas, prostate, cancers involving eye), brachytherapy (e.g. cervical, prostate, breast and skin cancers)
Cytotron a new treatment with an RFQMR technology is a non-invasive, safe and effective option to treat tumors by arresting cancer cell division leading to degeneration of the tumor. Thus, promising to relieve cancer patients of their pain, without side-effects of conventional treatment.
Proton therapy uses high energy particles (protons) instead of x-rays (photons) to deliver dose to a target volume. Proton therapy greatly improves dose conformity and the ability to spare healthy tissues thus allowing clinicians to treat tumors close to vital organs. Proton beam has been especially effective for skull base tumours, childhood cancers and prostate cancer.
VMAT (Volumetric Modulated Arc Therapy) radiotherapy technology advances the standard of care with uncompromised treatment in 2 minutes or less
Cancer surgeries such as for breast conservation surgery (lumpectomy or partial mastectomy) are used for early-stage breast cancers rather than mastectomy (removal of entire breast), cosmetic reconstructive surgery is used by cosmetic surgeons for a variety of cancer surgeries to provide excellent cosmesis (oral cancer, breast cancer soft tissue sarcomas etc.), sphincter preservation surgery for rectal tumors which are 4 cm or more. The part beyond cancer is preserved and the colon is then brought down and stapled to the rectum so that the patient can pass stools in a normal manner, robot assisted surgeries for breast, gastric cancers, prostate cancer are increasingly becoming popular.
Chemotherapy has advanced with targeted therapies, which are a group of newer drugs that specifically take advantage of gene changes in cells that cause cancer. Example imatinib for treatment of chronic myeloid leukemia, trastuzumab for breast cancers, sorafenib, sunitinib and pazopanib for kidney and liver cancers.
Monoclonal antibodies (without attached chemotherapy) are also being used as immunotherapy drugs, to strengthen the body’s immune response against cancer cells. Liposomal therapy uses chemotherapy drugs that have been packaged inside liposomes (synthetic fat globules). Examples are encapsulated form of doxorubicin and daunorubicin. Anti-angiogenesis drugs for cancers to grow, blood vessels must develop to nourish the cancer cells. This process is called angiogenesis. Bevacizumab was the first angiogenesis inhibitor that extended the lives of patients with some cancers. Anti-angiogenic drugs approved by FDA includes sorafenib, sunitinib, pazopanib and everolimus.
Cancer treatment vaccines have been developed to treat cancers that have already formed. FDA approved the first cancer treatment vaccine (Provenge®) for use in men with metastatic prostate cancer.
Cancer preventive vaccines target infectious agents that cause or contribute to the development of cancer. U.S. Food and Drug Administration (FDA) has approved two vaccines, Gardasil® and Cervarix®, that protect against infection by the two types of HPV- types 16 and 18 that cause approximately 70 percent of all cases of cervical cancer worldwide and 85% of cervical cancer cases in India, hence are likely to be very useful. Liver cancer or hepatocellular cancer develops in livers that were previously infected by Hepatitis B and Hepatitis C viral infection. If a public health measure is taken to provide Hepatitis B vaccination to the population at large, we can reduce the incidence of liver cancer over 15-20 years. It has been achieved in Denmark and Norway with health policy decision taken 2 decades ago.
Hormonal therapy with tamoxifen and aromatase inhibitors (Letrozole, Anastrozole) is now a standard in the treatment of women with estrogen receptor-positive breast cancers, both as an adjuvant therapy and in the treatment of advanced disease. Bicalutamide and gonadotrophin release homone analogues are extensively used for advanced prostate cancers.
These cancer treatment advancements are an endeavor of science and research to increase the survival rate and reduce treatment side effects on cancer patients.