Treatment of cancer has advanced by leaps and bounds over the last few decades and current gold standard management of most cancers involves judicious use of multiple modalities for optimal results. As a typical example, most breast cancers are now treated with a combination of surgery, chemotherapy, radiotherapy and hormonal therapy with or without immunotherapy. Multimodality management involves combined efforts of specialists in each individual treatment modality termed as surgical, medical and radiation oncologists respectively and treatment decisions are taken collaboratively based on stage, pathological type, immunohistochemistry and other tumour characteristics for each individual patient in adherence to international guidelines. Advances in imaging technology like biological imaging in the form of positron emission tomography - computed tomography (PET-CT) scan, high resolution magnetic resonance imaging (MRI) and computed tomography (CT) scans, and improvement in immunohistochemistry have all contributed in better typing and staging of malignancy in each individual patient – this has resulted in appropriate selection of the most effective multimodality treatment strategy through collaborative effort from surgical, medical and radiation oncologists based on scientific evidence in each case. Recent advances in each of the individual modalities have significantly improved treatment outcomes.
Surgical management of cancer
Surgical management of cancers has veered towards conservative approaches with preservation of organ and function and maintaining quality of life backed by paradigm shifts in effective adjuvant therapy. Breast, larynx, anal canal, rectum affected by cancer can be successfully preserved in appropriately selected cases with current conservative approaches. Often neoadjuvant treatment with chemotherapy and radiotherapy prior to planned surgery makes it possible for surgeons to remove smaller portions of affected organs due to tumour shrinkage, resulting in better cosmetic and functional outcomes.
Intensity modulated radiotherapy
Wide availability of intensity modulated radiotherapy over the last decade has placed tools for accurately targeting asymmetrically shaped tumours with very small normal tissue margins in the hands of modern radiation oncologists. The advent of Image guidance with the ability to image the patient’s anatomy on the treatment table during the radiotherapy process has brought about a sea change with radiation oncologists confidently delivering much higher doses with pin point accuracy – technical advances like respiratory gating have rendered mobile tumours accurate targets for radiation treatment. Dedicated stereotactic equipment have brought sub-millimeter accuracy and very high dose rates resulting in quick and accurate treatment making many erstwhile unsuitable conditions eminently treatable with short , accurate courses of radiotherapy with surgery like accuracy. Positron emission tomography based IGRT has helped radiation oncologists target higher radiation doses to metabolically aggressive tumour bearing areas where conventional doses were proving insufficient. True Beam is the latest technology revolutionizing the field of radiotherapy and bringing never before armamentarium into the hands of the radiation oncologists, with non flattened beams proving beneficial for IMRT, RapidArc and small field SRS treatments, decreasing out of field leakage or scatter dose to normal tissues and with dose rates up to 2400MU/min significantly decreasing treatment delivery times resulting in quicker and consequently accurate treatments with the surety of image guidance. This high performance treatment process combines the convenience of radiotherapy and radiosurgery on a single platform and significant increase in treatment accuracy helps the radiation oncologist choose the most appropriate treatment regimen for each patient sometimes opting for smaller number of higher dose treatments to add to patient convenience.
Several exciting new molecules including oral chemotherapy agents like Capecitabine and Temozolomide and several monoclonal antibodies have reached from bench to bedside in recent years and have changed the treatment scenario in many malignancies like colo-rectal malignancies, malignant brain tumours, renal cell carcinoma, non small cell lung cancers etc. The convenience of oral chemotherapy , the increasing efficacy of chemotherapy agents in general, wide availability of better drugs for amelioration of chemotherapy induced symptoms, and evolution of better targeted agents which exercise their effect on specific receptors associated with particular cancer cells have made systemic therapy more effective and better tolerated. Hormonal therapy has proven effective in hormone dependent cancers like breast and prostate cancer.
Recent advances in each of the treatment modalities have all contributed to better treatment with preservation of organ and function. The combined efforts of all oncology specialities are slowly but surely driving us to win the battle against cancer.
(Author is head of Radiation Oncology, HCG Cancer Center, Chennai)