Oncology is a special branch of medicine that deals with the study and treatment of cancer. The term oncology originates from the Greek word onkos meaning bulk or tumor.
Oncology mainly deals with the diagnosis of cancer, therapy which includes surgery, chemotherapy, radiotherapy and others.
The most significant diagnostic tool used in the study of oncology is medical history. It includes specific symptoms experienced by the patient and nature of complaint. Other diagnostic tools are
Biopsy - a medical test which involves removal of cells or tissues from possible area of malignancy for microscopic examination
Endoscopy - This involves internal examination of the patient's body by inserting a small scope to view the lesion.
X-Ray, CT scan, Ultrasound - These are radiological techniques used to examine the patient.
Blood Tests - Pathological examination like blood tests is a common technique to diagnose cancer.
Scintigraphy, Positron emission tomography - These are methods of nuclear medicine used to diagnose cancer.
Treatment of cancer depends on specific cases and the nature and extent of malignancy of the tumor. The most common methods of treatment are
Surgery - If the case permits, surgery or removal of the malignant portion of the body is removed.
Chemotherapy - It is the use of chemical substances to treat the disease. Often cytotoxic drugs are used for chemotherapy.
Radiotherapy - Ionizing radiation is used as a medical technique to cure and control the growth of malignant cells.
Hormone Manipulation - is mainly used in cases of breast and prostrate cancer
Vaccine - It is an antigenic preparation used to establish immunity to the disease.
To treat social problems like neglect and alienation, patients suffering from cancer or cured from cancer need palliative care. Physical problems that are associated with the treatment of cancer are pain, nausea, anorexia, fatigue and immobility.
Facilities in Hospitals
Oncology department has a special Tumour Board, comprising medical, surgical and radiation oncologists, and diagnostic consultants who provide comprehensive advice on the best course of treatment for patients. The department provides world-class cancer cure.
Surgical Oncology in India
What is Surgical Oncology?
An oncology that specializes in treating cancer by the means of surgery or by removing cancerous tissue or tumors is known as surgical oncology. Surgery is considered as one of the oldest treatment for cancer that not only helps in staging and diagnosing but also helps in curing many types of cancer. A surgery is also effective in treating those cancers that have not spread to any other body organ.
Conditions Treated by Surgical Oncology
- Soft tissue sarcomas
- Head and neck cancers
- Breast cancer
- Gastrointestinal cancer
- Rectum and Colon
- Endocrine Cancer
- Multiple Endocrine Neoplasia Types 1 and 2
- Adrenal Gland
- Neuroendocrine Tumors of the Gastrointestinal Tract
Surgical Oncology Procedures
Thyroidectomy : This procedure involves the removal of half or the entire thyroid for diagnosing and treating thyroid cancer.
Pancreatico duodenectomy or Whipple: This surgical procedure involves the removal of the head of the pancreas, growth on the duodenum and bile duct. A Whipple procedure may also be performed for strictures of the pancreatic duct or the bile and also for severe pancreatitis. The last part of the surgery aims at reconstructing the pancreas, the bile duct and the stomach.
Breast Surgery : Mastectomy, biopsy and segmental or lumpectomy are some of the types of surgical procedures that are included in breast surgeries for treating breast cancer.
Melanoma Excision : The risk of recurrence of melanoma (a skin cancer) is reduced by making a wide excision of normal healthy skin around the affected part. The depth of the melanoma determines the width of the resection.
Rectal or Colon Resection : The rectal or colon cancer involves the removal of a part of the rectum or colon. In some cases, the bowel is re-connected so as to avoid a ostomy or stoma.
Distal Pancreatectomy : The end of the pancreas is surgically removed by performing a distal pancreatectomy. Injury, pancreatic cancer, pancreatic pseudocysts and chronic pancreatitis can be treated with the help of this procedure.
Gastrectomy : Gastrectomy is a procedure that involves the removal of a part or the entire stomach. The procedure is performed for treating stomach cancer or gastric cancer.
Liver Resection : This is considered as a treatment option for primary liver cancer and sometimes for metastatic liver cancer. Different types of liver tumors can be removed by performing the surgical procedure of liver resection. The primary aim is to remove all affected tissue and the tumors by leaving as much liver as possible.
Lymph Node Dissection : This procedure is primarily performed for treating skin or breast cancer. This can be either completion lymph node dissection or sentinel lymph node. The completion lymph node dissections involve the removal of all the lymph nodes from an area of the body that include groin or armpit. On the other hand, sentinel lymph node involves the removal of the first few lymph nodes that drain the affected area.
Esophagectomy : This procedure is performed for removing a part or the entire of the esophagus. The aim of the procedure is to treat esophagus cancer.
Surgical Oncology Techniques
Endoscopic Ultrasound (EUS): This surgical oncology technique allows –
- To obtain samples by passing a needle inside the tumor that provides for a quick and precise diagnosis.
- It also helps in determining the location and size of the tumor in the pancreas by providing a clear visualization of the pancreas and the digestive tract.
Minimally Invasive Surgery : Very small incisions are made for performing this minimally invasive surgery. This surgery makes use of certain specialized techniques either robotically with the Da Vinci surgical robot or laparoscopically. The procedure is performed by using high definition monitors, miniature cameras with microscopes and tiny fiber-optic flashlights. Only an incision or a stitch is required for performing this procedure. The major benefit of this procedure is that it results in less blood loss and quick recovery.
Stereotactic Breast Biopsy : This minimally invasive is considered as a safe form for breast biopsy. This technique is used for taking small samples of an abnormal breast mass for examining them. A breast abnormality is cancerous or non-cancerous is confirmed by these biopsies.
Radiofrequency Ablation : A thin needle guided by an ultrasound or computed tomography (CT) is inserted through the skin into the tumor. The tumor is heated and destroyed by delivering electrical energy by the needle. In majority of cases, a tumor can be effectively treated with the help of radiofrequency ablation in just one treatment session.
Reconstructive Surgery : The primary aim of a reconstructive surgery is to reconstruct an affected area from where surgical removal of the cancer has been done. This type of surgery is mainly used by plastic surgeons.
Sentinel Lymph Node (SLN) Biopsy : The first lymph node from where the cancer spreads from the primary tumor is known as the sentinel lymph node. Sentinel lymph node is the first lymph node where cancer cells first appears. More than one sentinel lymph node may also be present. The presence of cancer cells is determined and examined under a microscope by performing a SLN biopsy procedure that involves the removal of the sentinel lymph node.
Mohs’ Surgery : The cancer from the sensitive areas of the skin is removed with the help of this surgery. The cancer layer is carefully removed with the help of scalpel that is then examined under a microscope.
Electrosurgery : Cancer cells are destroyed by applying high-frequency electrical currents.
Cryosurgery : A cold probe or liquid nitrogen (a very cold material) is used for freezing and destroying the cancer cells.
Robotic Surgery : This surgery can be easily operated by a surgeon who sits away from the operating table and views the 3-D image on the screen of the area being treated. A surgeon controls the movement of a robot and also tells him how to use surgical tools for performing the operation. Robotic surgery is considered very beneficial for treating various types of cancer.
Radiation Oncology in India
What is Radiation Oncology?
A medical specialty that makes use of different types of radiation for treating cancer and other diseases is known as radiation oncology. The treatment has proved itself as a powerful weapon to fight against cancer and results in increased number of cancer cures. High-energy radiation is used for shrinking and destroying cancer cells. The different types of radiation used for treating cancer include charged particles, x-rays and gamma rays. The delivery of this radiation can be done either from a radioactive material placed into the body close to cancer cells (Brachytherapy or internal radiation) or through a machine that is placed outside the body. Radioactive iodine (a radioactive substance) is used in systemic radiation therapy that travels throughout the body for killing cancer cells.
The different types of radiation therapy depends on several factors such as –
- Medical condition and age of a patient
- The type of cancer
- Medical history and general health of a patient
- The location of cancer in the body
- Whether a patient also requires other types of cancer treatments
- The size of the cancer
- How far a radiation needs to travel in the body
- Is cancer located close to normal tissues that are sensitive to radiation
Radiation Therapy Treatment Options
Internal radiation therapy and external radiation therapy are the two treatment options for radiation therapy.
Internal Radiation (Brachytherapy) : The delivery of this radiation is done through radiation sources that are either placed on the body or inside the body. There are different Brachytherapy techniques that are used for treating cancer. The melanoma in the eye can be treated with the help of Episcleral Brachytherapy that makes use of a source attached to the eye. A source is placed close to a tumor either inside the body cavity or in a surgical cavity in the case of Intracavitary Brachytherapy. The placement of a radiation source is done inside the tumor tissue in the case of Interstitial Brachytherapy.
Brachytherapy can cause less damage to the nearby normal tissues and can be given either as a high-dose or a low-dose treatment –
- The delivery tubes are attached with a robotic machine that are placed within the body guides one or more radioactive sources near or into a tumor in the case of high-dose treatment. The removal of these sources is then done at the end of every treatment session. More than one treatment sessions can be used in the case of high-dose treatment. MammoSite system is the best example of a high-dose treatment that is used for treating breast cancer for those patients who have gone through breast-conserving surgery.
- A continuous low-dose radiation is given to the cancer cells through a source that may take some days in the case of low-dose treatment.
External-Beam Radiation Therapy : The delivery of this therapy is primarily done in the form of photon beams. A photon can be considered as a collection of energy and is a unit of light along with different forms of electromagnetic radiation. The energy of a photon also may vary. The total radiation dose is the determining factor of external beam radiation treatment. 3-Dimensional Conformal Radiation Therapy (3D-CRT) is considered as the most common type of external beam radiation. The radiation is delivered precisely by concentrating on the affected areas by using advanced treatment machines and computer software.
External beam radiation other methods for treating cancer include –
- Stereotactic Body Radiation Therapy (SBRT) : Few treatment sessions are required for delivering radiation therapy by using high doses and small radiation fields. This therapy helps in treating those tumors that lie outside the spinal cord and brain. More than one dose is used in this therapy for treating isolated and small tumors such as lung and liver cancers. Cyberknife radio surgery is a type of stereotactic body radiation therapy that is considered as a non-invasive alternative to surgery. Cyberknife can treat tumors located anywhere in the body with precise accuracy. There is minimum damage caused to the surrounding healthy tissues and structures including optic nerve or spinal cord.
- Intensity-Modulated Radiation Therapy (IMRT) : This therapy makes use of a number of small radiation beam-shaping devices known as collimators for delivering a single dose of radiation. The intensity of the radiation beams can be changed at the time of treatment sessions by either moving the collimators or by keeping them stationary. IMRT involves inverse treatment planning that delivers radiation doses to surrounding tissue and to different areas of the tumor. The required number of angles and beams of the radiation treatment is calculated by high-powered computer program. The ultimate goal is to raise the radiation dose to the different areas and thereby reducing the radiation exposure to certain sensitive areas of nearby normal tissue.
- Stereotactic Radiosurgery (SRS) : More than one high doses of radiation can be delivered to a tiny tumor in this method. This method makes use of extreme accurate image-guided patient positioning and tumor targeting. SRS is commonly used for treating brain metastases, spinal or brain tumors from other types of cancer. The high dose can only be delivered accurately by using other devices or a head frame for immobilizing the patient at the time of treatment. The stereotactic radiosurgery can be best delivered by using the latest tool known as the Novalis TX. This technology helps to focus precisely and delivers high doses of tumor for destroying the tumor. It also results in minimally damage to the nearby tissue and can be performed faster along with other machines.
- Tomotherapy: This is considered as a type of image-guided IMRT. The machine used by tomotherapy is a combination of external-beam radiation therapy and a CT imaging scanner machine. This tomotherapy machine can be easily rotated around the patient and delivers radiation for both treatment and imaging. The precise treatment can be given as this machine captures CT images of a patient just before the beginning of the treatment.
- Proton Therapy : Both Photon beams and proton beams can deliver external beam radiation therapy. The main difference between the two is terms of the deposition of energy in the living tissue. High-doses of radiation can be delivered to a tumor by using protons that may help in reducing the exposure of normal tissue to radiation.
- Image-Guided Radiation Therapy (IGRT) : A number of imaging scans such as PET, CT or MRI are performed at the time of treatment. These imaging tests help to recognize changes of the location and size of a tumor. It also provides proper adjustment of the planned radiation dose during treatment. The accuracy of radiation treatment can be increased by providing continuous imaging and it may also decrease the amount of total radiation dose to a normal tissue.
Systemic Radiation Therapy
A patient can either receive or swallow a radioactive substance that includes a radioactive substance bound to a monoclonal antibody or radioactive iodine. Different types of thyroid cancer can be treated with the help of radioactive iodine (a type of systemic radiation). The radioactive substance is targeted by a monoclonal antibody in systemic radiation therapy. The radioactive substance is then attached to the antibody that travels from the blood and finally destroys the cancer cells.
Bone Marrow Transplant (BMT)
Intensity Modulated Radiation Therapy
Stem Cell Cancer Treatment
Image Guided Radiotherapy
Image Guided RadioSurgery
Stereotactic Body Radiation Therapy
Volumetric Modulated Arc Therapy