Oncology
Oncology is a branch of medicine that deals with the prevention, diagnosis, and treatment of cancer. A medical professional who practices oncology is an oncologist. The name's etymological origin is the Greek word ὄγκος, meaning 1. "burden, volume, mass" and 2. "barb", and the Greek word λόγος, meaning "study".
Cancer survival has improved due to three main components: improved prevention efforts to reduce exposure to risk factors, improved screening of several cancers, and improvements in treatment.
Cancers are often managed through discussion on multi-disciplinary cancer conferences where medical oncologists, surgical oncologists, radiation oncologists, pathologists, radiologists, and organ specific oncologists meet to find the best possible management for an individual patient considering the physical, social, psychological, emotional, and financial status of the patient. It is very important for oncologists to keep updated with respect to the latest advancements in oncology, as changes in management of cancer are quite common.
Because a cancer diagnosis can cause distress and anxiety, clinicians may use a number of strategies such as SPIKES for delivering the bad news.
Risk factors
;Tobacco: The leading cause of cancer, and death from cancer. Smoking is associated with increased risk of cancers of the lung, larynx, mouth, oesophagus, throat, brain, bladder, kidney, liver, stomach, pancreas, colon, rectum, cervix and acute myeloid leukemia. Smokeless tobacco is associated with increased risks of cancers of the mouth, oesophagus, and pancreas.;Alcohol: Can increase risk of cancer of the mouth, throat, oesophagus, larynx, liver, and breast. The risk of cancer is much higher for those who drink alcohol and also use tobacco.
;Obesity: Obese individuals have an increased risk of cancer of the breast, colon, rectum, endometrium, oesophagus, kidney, pancreas, and gallbladder.
;Age: Advanced age is a risk factor for many cancers. The median age of cancer diagnosis is 66 years.
;Cancer-Causing Substances: Cancer is caused by changes to certain genes that alter the way our cells function. Some of them are the result of environmental exposures that damage DNA. These exposures may include substances, such as the chemicals in tobacco smoke, or radiation, such as ultraviolet rays from the sun and other carcinogens.
;Infectious Agents: Certain infectious agents, including oncoviruses, bacteria, and parasites, can cause cancer.
;Immunosuppression: The body's immune response plays a role in defending the body against cancer, a concept known mainly because certain cancers occur at a greatly increased prevalence among people with immunosuppression.
Screening
is recommended for cancers of breast, cervix, colon, and lung.Signs and symptoms
Signs and symptoms usually depend on the size and type of cancer.; Breast cancer: Lump in breast and axilla associated with or without ulceration or bloody nipple discharge.
; Endometrial cancer: Bleeding per vagina.
; Cervix cancer: Bleeding after sexual intercourse.
; Ovarian cancer: Nonspecific symptoms such as abdominal distension, dyspepsia.
; Lung cancer: Persistent cough, breathlessness, blood in the sputum, hoarseness of voice.
; Head and neck cancer: Non-healing ulcer or growth, lump in the neck.
; Brain cancer: Persistent headache, vomiting, loss of consciousness, double vision.
; Thyroid cancer: Lump in the neck.
; Oesophageal cancer: Painful swallowing predominantly with solid food, weight loss.
; Stomach cancer: Vomiting, dyspepsia, weight loss.
; Colon & rectal cancer: Bleeding per rectum, alteration of bowel habits.
; Liver cancer: Jaundice, pain and mass in right upper abdomen.
; Pancreatic cancer: Weight loss, jaundice.
; Skin cancer: Non-healing ulcer or growth, mole with sudden increase in size or irregular border, induration, or pain.
; Kidney cancer: Blood in urine, abdominal lump.
; Bladder cancer: Blood in urine.
; Prostate cancer: Urgency, hesitancy and frequency while passing urine, bony pain.
; Testis cancer: Swelling of testis, back pain, dyspnoea.
; Bone cancer: Pain and swelling of bones.
; Lymphoma: Fever, weight loss more than 10% body weight in preceding 6 months and drenching night sweats which constitutes the B symptoms, lump in neck, axilla or groin.
; Blood cancer: Bleeding manifestations including bleeding gums, bleeding from nose, blood in vomitus, blood in sputum, blood stained urine, black coloured stools, fever, lump in neck, axilla, or groin, lump in upper abdomen.
Diagnosis and staging
Diagnostic and staging investigations depend on the size and type of malignancy.Blood cancer
Blood investigations including hemoglobin, total leukocyte count, platelet count, peripheral smear, red cell indices.Bone marrow studies including aspiration, flow cytometry, cytogenetics, fluorescent in situ hybridisation and molecular studies.
Lymphoma
Excision biopsy of lymph node for histopathological examination, immunohistochemistry, and molecular studies.Blood investigations include lactate dehydrogenase, serum uric acid, and kidney function tests.
Imaging tests such as computerised tomography, positron emission tomography.
Bone marrow biopsy.
Solid tumors
for histopathology and immunohistochemistry.Imaging tests like X-ray, ultrasonography, computerised tomography, magnetic resonance imaging and PET CT.
Endoscopy including Naso-pharyngoscopy, Direct & Indirect Laryngoscopy, Upper Gastrointestinal Endoscopy, Colonoscopy, Cystoscopy.
Tumor markers including alphafetoprotein, Beta Human Chorionic Gonadotropin, Carcinoembionic Antigen, CA 125, Prostate specific antigen.
Treatment
Treatment depends on the size and type of cancer.Solid tumors
; Breast cancer: Treatment options include surgery, radiation, chemotherapy, hormonal therapy, and targeted therapy.; Cervix cancer: Treatment options include radiation, surgery and chemotherapy.
; Endometrial cancer: Treatment options include surgery, radiation, and chemotherapy.
; Ovary cancer: Treatment options include surgery, chemotherapy, and targeted therapy.
; Lung cancer: Treatment options include surgery and robot-assisted surgery, radiation, chemotherapy, and targeted therapy.
; Head & Neck Cancer: Treatment options include surgery, radiosurgery, radiation, chemotherapy, and targeted therapy.
; Brain cancer: Treatment options include surgery, radiosurgery with the Cyberknife System, radiation, chemotherapy, and targeted therapy.
; Thyroid cancer: Treatment options include surgery and radioactive iodine.
; Oesophageal cancer: Treatment options include radiation, chemotherapy, and surgery.
; Stomach cancer: Treatment options include chemotherapy, surgery, radiation, and targeted therapy.
; Colon cancer: Treatment options include surgery, chemotherapy, and targeted therapy.
; Rectum cancer: Treatment options include chemotherapy, radiation, surgery.
; Liver cancer: Treatment options include surgery, Trans-arterial chemotherapy, Radio-frequency ablation, and multi-kinase.
; Pancreas cancer: Treatment options include surgery, radiation, and chemotherapy.
; Skin cancer: Treatment options include surgery, radiation, targeted therapy, Immunotherapy.
; Bladder cancer: Treatment options include surgery, radiation, and chemotherapy.
; Prostate cancer: Treatment options include surgery, radiation, chemotherapy, anti-androgens, and immunotherapy.
; Testis cancer: Treatment options include surgery, chemotherapy, and radiation.
; Bone cancer: Treatment options include surgery, chemotherapy, and radiation.
Lymphoma
It includes Hodgkin lymphoma and non-Hodgkin lymphoma :;Hodgkin lymphoma : Chemotherapy with ABVD or BEACOPP regimen and Involved field radiation therapy.
;Non-Hodgkin lymphoma : Chemo-immunotherapy for B cell lymphomas, and chemotherapy for T cell lymphomas.
Blood cancer
Includes acute and chronic leukemias. Acute leukemias includes acute lymphoblastic leukemia, and acute myeloid leukemia. Chronic leukemias include chronic lymphocytic leukemia, and chronic myeloid leukemia.; Acute lymphoblastic leukemia : Intensive chemotherapy phase for initial 6 months and maintenance chemotherapy for 2 years. Prophylactic cranial and stem cell transplantation for high-risk patients.
; Acute myeloid leukemia : Induction with chemotherapy, followed by consolidation chemotherapy. Stem cell transplantation for high-risk patients.
; Chronic myeloid leukemia : Targeted therapy with tyrosine kinase inhibitor as first-line treatment.
Specialties
- The three main divisions:
- * Medical oncology: focuses on treatment of cancer with chemotherapy, targeted therapy, immunotherapy, and hormonal therapy.
- * Surgical oncology: focuses on treatment of cancer with surgery.
- * Radiation oncology: focuses on treatment of cancer with radiation.
- Sub-specialties in Oncology:
- * Neuro-oncology: focuses on cancers of brain.
- * Ocular oncology: focuses on cancers of eye.
- * Head & Neck oncology: focuses on cancers of oral cavity, nasal cavity, oropharynx, hypopharyx and larynx.
- * Thoracic oncology: focuses on cancers of lung, mediastinum, oesophagus and pleura.
- * Breast oncology: focuses on cancers of breast
- * Gastrointestinal oncology: focuses on cancers of stomach, colon, rectum, anal canal, liver, gallbladder, pancreas.
- * Bone & Musculoskeletal oncology: focuses on cancers of bones and soft tissue.
- * Dermatological oncology: focuses on the medical and surgical treatment of skin, hair, sweat gland, and nail cancers
- * Genitourinary oncology: focuses on cancers of genital and urinary system.
- * Gynecologic oncology: focuses on cancers of the female reproductive system.
- * Pediatric oncology: concerned with the treatment of cancer in children.
- *Adolescent and young adult oncology.
- * Hemato oncology: focuses on cancers of blood and stem cell transplantation
- * Preventive oncology: focuses on epidemiology & prevention of cancer.
- * Geriatric oncology: focuses on cancers in elderly population.
- * Pain & Palliative oncology: focuses on treatment of end stage cancer to help alleviate pain and suffering.
- *Molecular oncology: focuses on molecular diagnostic methods in oncology.
- * Oncopathology: A specialty of Pathology that focuses on the histopathological diagnosis of cancer. As a significant portion of all general pathology practice is concerned with cancer, the practice of oncology is deeply tied to, and dependent upon, the work of both anatomical and clinical pathologists.
- * Nuclear medicine oncology: focuses on diagnosis and treatment of cancer with radiopharmaceuticals.
- * Psycho-oncology: focuses on psychosocial issues on diagnosis and treatment of cancer patients.
- * Veterinary oncology: focuses on treatment of cancer in animals.
- Emerging specialties:
- *Computational oncology. An example is PRIMAGE. This four-year EU-funded Horizon 2020 project was launched in December 2018. The project proposes a cloud-based platform to support decision making in the clinical management of malignant solid tumours, offering predictive tools to assist diagnosis, prognosis, therapies choice and treatment follow up, based on the use of novel imaging biomarkers, in-silico tumour growth simulation, advanced visualisation of predictions with weighted confidence scores and machine-learning based translation of this knowledge into predictors for the most relevant, disease-specific, Clinical End Points.
Research and progress
- Leukemia, Lymphoma, Germ cell tumors and early stage solid tumors which were once incurable have become curable malignancies now. Immunotherapies have already proven efficient in leukemia, bladder cancer and various skin cancer. For the future, research is promising in the field of physical oncology.
- Survival of cancer has significantly improved over the past years due to improved screening, diagnostic methods and treatment options with targeted therapy.
- Large multi-centric Phase III randomised controlled clinical trials by the National Surgical Adjuvant Breast & Bowel Project Medical Research Council, the European Organisation for Research and Treatment of Cancer, and National Cancer Institute have contributed significantly to the improvement in survival.