What Is an Oncologist?

When the cells in the body begin to deviate from their normal pattern of maturity, reproduction and death, this is how cancer begins. Regardless of the area or type of cancer, the disease itself begins with abnormal cell growth.  Millions of Americans have had cancer or currently have cancer. It is the second-leading cause of death in the United States, with about 50% of men and 30% of women developing some form of cancer in their lifetimes.

An oncologist is a physician who specializes in the diagnosis and treatment of cancers and tumors.  They may also be referred to as cancer specialists. The National Cancer Institute (NCI) defines a medical oncologist as (NCI, 2017): A doctor who has special training in diagnosing and treating cancer in adults using chemotherapy, hormonal therapy, biological therapy, and targeted therapy. A medical oncologist often is the main health care provider for someone who has cancer and gives supportive care and may coordinate treatment given by other specialists.

An oncologist will have a long-term relationship with their patient, from diagnosis throughout the course of the disease.  They will explain the cancer diagnosis so the patient has a clear understanding of his or her condition.  The oncologist will also discuss all treatment options and provide their recommendation. Pain management and management of other symptoms is also one of the primary duties of an oncologist.

Oncologists work with patients at varying stages and levels of distress, in addition to those who have a difficult time acknowledging their diagnosis. They must offer compassionate care and understanding to their patients and their families.

Oncologists working in a hospital setting may also have educational duties including training medical students, residents, and other staff.  In a purely academic capacity, oncologists may also conduct clinical trials for new cancer treatments.


What Does an Oncologist Do?


The most important diagnostic tool remains the clinical history of the patient. Common symptoms that point towards cancer include fatigue, weight loss, unexplained anemia, fever of unknown origin, and more (Mandal, 2017). Blood tests are also commonly used to identify markers that may indicate the presence of cancer or abnormal cell growth.

A biopsy is another diagnostic tool used by oncologists. During a biopsy, the oncologist removes tiny bits of the tumor tissue so they can examine it microscopically. Other diagnostic tools include endoscopy for the gastrointestinal tract, imaging studies like X-rays, CT scanning, MRI scanning, ultrasound and other radiological techniques, scintigraphy, single photon emission computed tomography, positron emission tomography and nuclear medicine techniques etc. (Mandal, 2012).



Cancer remains incurable to this day, although there have been significant medical advances in diagnostic methods that improve early diagnosis and detection of cancer.  Remission refers to a person who had cancer at one time but has eradicated the disease with treatment or therapy. Although remission indicates a recovery, the cancer can return even after months or years of remission, so there is always a risk that the cancer will return. Any patient who has or had cancer at one time should continue with therapy and follow-up appointments to detect any presence or reappearance of the cancer.

The therapy prescribed varies depending on the grade and stage of the cancer. Therapies may include surgery, chemotherapy, or radiation therapy. The type of therapy prescribed by the oncologist depends on a variety of factors.  In addition to the grade (aggressive nature of the cancer) and the stage of cancer, other factors include the type, the patient’s general health and the patient’s acceptability of the treatment.



An oncologist will also perform cancer screening. By identifying the genes that are associated with cancer, preventative measures can be implemented to reduce the risk of cancer developing. For example, in breast cancer both population screening by regular mammography and familial screening by genetic analysis of the BRCA1 and BRCA2 genes is performed (Mandal, 2012).



Research continues to be conducted in all areas of oncology, as this is a continuously changing and developing field.  Much remains to be known about the development of cancer and how to prevent it or cure the disease. Research areas may include cancer cell biology, chemotherapy treatments, optimal palliative care and pain relief. Most research activities are done using clinical trials, in which patients may voluntarily enroll.



Several surgical techniques are used to treat some cancers. There are two types of surgical therapy – prophylactic surgery and therapeutic or curative surgery. The patient may elect for prophylactic surgery that involves removal of tissue that is not malignant but which may become malignant. A common example is prophylactic or precautionary removal of the breasts in women with a mutation in the BRCA gene that raises their risk of getting breast cancer (Mandal, 2012). Curative surgery involves removal of the cancerous tumor and is typically combined with other therapy treatments, such as chemotherapy.

Palliative surgery is used to treat complications that advanced cancer may cause, although it may be used for tumor removal as well. This type of surgery may be used to remove the bulk of a tumor that is blocking organs from functioning properly, and it may also be used as a pain relief treatment.


Radiation Therapy

Radiation is most effective on cells in the dividing stages and less effective on cells in the “resting” phase of G0, and it aims to stop cancer cells from dividing, thus killing them and destroying the tumor (Mandal, 2012).  The cells within the body have a continuous cycle, with each stage identified as G0, G1, S, G2 and M. The drawback of radiation therapy is that it may also attack healthy cells in addition to the cancerous cells. Healthy cells that line the mouth and hair cells are often destroyed by radiation therapy.

Healthy blood cells and other active cells within the body may also be targeted by the radiation, which is why many radiation therapy patients have low white blood cell counts.  Low white blood cell counts make the patient susceptible to infections, and low red blood cell counts may lead to anemia. Radiation therapy may also lead to low blood platelet counts, which can lead to excessive bleeding or the inability of the blood to clot.

During a typical radiotherapy process, the patient will receive a dose of radiation over an extended period of time, typically 5 days a week for 6 weeks to begin with.  Weekends are used for recovery and to allow the dead cells time to leave the body. The radiation may be introduced by an external beam at varying strengths depending on how rapidly the tumors are dividing. Radiation may also be implanted internally, and the implant slowly releases the radiation dose over the course of several days. Internal radiation is also known as brachytherapy.



Chemotherapy is the administration of drugs to kill cancer cells, and it can be administered via pill, injection or intravenous infusion (Mandal, 2012). Just as with radiation therapy, chemotherapy targets rapidly developing cells with the goal of disrupting cell division. It may also be used in conjunction with surgery to ensure any cancer cells that weren’t removed are killed. Most forms of chemotherapy fall under an antineoplastic or anticancer category.

There are generally 3 stages of chemotherapy: induction, consolidation and maintenance. Induction is the initial intensive phase, consolidation is the stabilization phase, and the maintenance phase is the stage of longest duration. The duration depends on the type of cancer and the type of response, such as shrinkage of the tumor or progression of the disease. Neoadjuvant chemotherapy refers to treatment given prior to surgery, and adjuvant refers to chemotherapy given after surgery.

A variety of chemotherapy options are available for oncologists to choose from depending on the patient’s needs and the specifics of their disease.

Hormonal therapy is used for hormone dependent cancers like breast cancer or prostate cancer. Anti-angiogenesis therapies are used to prevent the formation of new blood vessels in the tumors which leads to their eventual “starvation” and death.  Photodynamic therapy combines light and a photosensitizing agent, which accumulates in the diseased organ. When exposed to laser light, the chemicals produced from the drug kill the cancer cells (Mandal, 2012).

Gene therapy aims to alter the genetic makeup of the tumor or of the body by inserting a desirable gene into the DNA of cells that have been removed from the patient (Mandal, 2012). The cells that have been removed are then reprogrammed and reinserted into the patient’s body. In some cases, the reprogrammed cells fortify the patient’s immune system, and in others, the reprogrammed cells assist the action of other chemotherapy drugs.

Bone marrow transplantation and stem cell transplantation are other new modalities which are often used as the primary therapy for blood cancers like leukemias and lymphomas. Bone marrow transplants are also being used as experimental treatments for other cancers as well.


Oncology Sub-Specialties

Oncology is a medical specialty in itself, but there are also sub-specialties that exist within the field of oncology.  The area affected by the cancer, such as the breast, prostate, lungs, blood cells, colon or other area, has its own unique response to the growth of cancer. The cancer itself varies as well, perhaps by severity, aggressiveness or cellular type.  Due to the unique aspects of each organ and grade of cancer, effective treatments will vary greatly.

There are many sub-specialties of oncology.  Radiation oncology is the use of radiation therapy in treating cancer. Surgical oncology involves surgeons who are skilled in cancer and tumor removal. Since cancers are highly vascular (rich in blood supply), and surgical oncologists require extensive training to develop the skills needed for this type of surgery.

Medical oncologists are involved with the treatment of cancer using chemotherapeutic agents. In the United States, the terms clinical oncologist and medical oncologist are used interchangeably.  A medical oncologist is the team coordinator who will manage diagnosis and treatment plans and any cancer-related problems or issues that may arise.

Interventional oncologists are interventional radiologists who specialize in minimally invasive image guided tumor therapies. Gynecologic oncologists work with patients who have cancers of the female reproductive organs. Pediatric oncologists specialize in childhood cancers. Neuro-oncologists focus on cancers of brain and spinal cord. Hemato-oncologists work with blood cell cancers, and uro-oncology is the study of cancers of the urogenital tract.

Oncologists work as part of a multi-disciplinary medical team in order to provide comprehensive medical care to the cancer patient.  

A pathologist examines the blood or tissue of the tumor or organ that was removed during a biopsy. The biopic material is examined under a microscope to identify the presence or absence of cancer cells. This is an important role, because the treatment and therapy prescribed is based on the pathologist’s analysis of the test results.

Also included in the medical team may be (Mandal, 2012):

Specialized doctors of the concerned organ system involved. For example, liver cancer patients need a Gastrointestinologist on the team and a brain cancer patient likewise needs a neurologist on the team.

A cosmetic surgeon or reconstructive surgeon – in some cases, after-surgery reconstruction of the damaged organ may be needed. For example, in breast cancer patients, these surgeons help in recreating the removed breast and nipple using tissues from other parts of the body.

A physician’s assistant helps in diagnosis and treatment under the direct supervision of a physician, and an oncology nurse provides day-to-day care while in the hospital. Oncology nurses are specially trained in managing cancer patients.

A social worker plays an important role in helping the patient navigate the health care system, and also helps in coping with the economic and emotional burden of the cancer diagnosis and treatment.

A physical and occupational therapist may be required for patients who become disabled or physically weak after chemotherapy or other treatment.

An anesthetist or expert in pain management for terminal stage cancer pain management, and a diet advisor or nutritional therapist to advise on the appropriate and healthy diet during and after cancer therapy.


How to Become an Oncologist

To become an oncologist, you will need over a decade of education and training. An undergraduate degree, completion of medical school and a residency program are all required to become a licensed oncologist. Many oncologists who pursue a sub-specialty obtain an additional certification, although this is optional.  Licensing, however, is mandatory.

As mentioned above, the first step to becoming an oncologist is to obtain a bachelor’s degree.  Many future oncologists major in biological science, chemistry, physics or pre-medical, although there is no specific requirement for a major. Science programs typically have the classes and subjects that meet the standards to admittance into medical school.


Medical School

The Medical College Admission Test (MCAT) will be taken during the third year of undergraduate study. Medical schools use this exam as a skills assessment to evaluate an applicant’s training and knowledge. In addition to the minimum requirements, volunteering at a hospital or medical center not only allows for hands-on training working with patients, but it may help an applicant stand out to the medical evaluation board.  Participation in extra-curricular activities and learning a foreign language may also be beneficial in standing out and increasing the chances of acceptance into medical school.

Medical school typically consists of a four-year program.  The first two years focus on classroom instruction of anatomy and physiology, biochemistry, pathology and pharmacology.  The last two years includes hands-on clinical training covering specialized medicinal areas such as pediatrics or surgery.  A Doctorate of Medicine (M.D. or Ph.D.) is rewarded after successful completion of the 4-year medical school program.



After graduation from medical school, a 3 to 4-year residency must be completed. Many oncologists obtain internal medicine residency training. Surgical oncologists must first complete a general surgery residency 5-year program before pursuing a 3-year surgical oncology fellowship for specialized tumor surgery training. Pediatric and gynecological oncologists also complete additional fellowship training in their sub-specialty field.



Oncologists pursuing a sub-specialty will need a fellowship program in order to gain the additional skills and training required. A fellowship typically lasts two years. When the residency or fellowship is completed, the aspiring oncologist will take the licensing exam and if they choose, apply for board certification. Certification is offered by the American Board of Obstetrics and Gynecology (ABOG), American Board of Internal Medicine (ABIM), American Board of Pediatrics (ABP), American Board of Radiology (ABR) or the American Board of Surgery (ABS).

Although many oncologists practice in hospitals, others may be employed at medical centers, pediatric hospitals, surgical centers, outpatient clinics, nursing homes, prisons, public health centers, health care organization and within many other industries (Doctorly, 2017). Some may also choose to open their own private practice. Other career opportunities include college or university settings in an academic position, and clinical research, where the oncologist is devoted solely to researching treatment alternatives or performing studies for pharmaceutical development.


Additional Skills Needed

In addition to education and training, and oncologist will need a variety of other skills to be successful. Lawler (2016) identifies the following qualities an oncologist should possess:

  • Excellent communication skills, which help with discussion of treatment options, as well as the associated risks and benefits.
  • Excellent interpersonal skills, with patients (and their families), as well as other medical professionals/staff.
  • Demonstrates good interpretative and analytical skills, as medical knowledge alone does not fully support a career in oncology.
  • The ability to remain emotionally detached from a situation in order to stay effective as a medical expert yet still able to address and provide support to patients with compassion.
  • Patience, a positive attitude and inner strength, to mentally and emotionally deal with terminal cases.
  • Works well with a team, as the treatment of a patient may include the knowledge and assistance of a pathologist, diagnostic radiologist, oncology nurse, and sometimes, a social worker or therapist.
  • In some cases, having an open mind regarding non-traditional methods of healing and/or treatment.




Job Prospects

The median annual income for oncologists is over $243,000. The U.S. Bureau of Labor Statistics identifies an expected job growth of 14% by 2024. Sub-specialists and surgeons tend to make higher salaries than oncologists alone. The average annual income of a sub-specialist or surgeon is over $300,000.

The job growth expected for oncologists is sure to be surpassed, particularly for sub-specialized fields. Many rural and underprivileged areas already have a shortage of oncologists which is sure to grow in the future.


A Brief History of Oncology

Scientists have discovered evidence of bone cancer dating back to ancient Egypt. Human mummies and ancient scripts have been analyzed and reviewed for their descriptions of cancer, including mention of tumors, ulcers and cauterization. At the time, the Egyptians described the condition as incurable, dating back as far as 3000 BC.

During the eighteenth century, Giovanni Morgagni introduced the practice of autopsy, which led the way to the scientific study of many diseases, including cancer. The field of cancer epidemiology also emerged in the eighteenth century, leading to the identification of the association between environmental exposures and the development of the disease.

The next century saw Rudolf Virchow introduce the microscope, which led to even further medical advances and discoveries. Advancements in cancer therapy in the late nineteenth and early twentieth centuries included improvements in surgery, the use of radiation therapy, and the first chemotherapy agents (following the discovery during World War II that nitrogen mustard kills cancer cells). Many medical advances were made during and after World War II, and, due to the large number of soldiers surviving what were once fatal injuries, the medical profession boomed.

Since the 1940s, the field of oncology has grown rapidly, with refinements in surgical technique and use of less invasive procedures, modifications and innovation in radiation therapy, which is associated with less morbidity, and the development of targeted biologic chemotherapy agents. This medical specialty covers many organ systems and is constantly changing, with new screening guidelines, diagnostic tests, and drug discoveries announced on an annual basis.





NCI – National Cancer Institute. Dictionary of Cancer Terms. Retrieved September 25, 2017 from: https://www.cancer.gov/publications/dictionaries/cancer-terms?cdrid=46290


Mandal, Ananya, MD. What is Oncology? News Medical Life Sciences. October 28, 2012. Retrieved September 26, 2017 from: https://www.news-medical.net/health/Oncology-Specialties.aspx


Lawler, Carlton. On the Job: What Does an Oncologist Do? Communication Shutdown. August 15, 2016.  Retrieved September 26, 2017 from: http://www.communicationshutdown.org/on-the-job-what-does-an-oncologist-do/


Doctory.org. How to Become an Oncologist. 2017. Retrieved September 26, 2017 from: http://doctorly.org/how-to-become-an-oncologist/


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