Oncology: What is it? Diagnosis, Care and Prevention of A.Griguolo Cancer

Generality

Oncology is the branch of medicine that is dedicated to the diagnosis, treatment and prevention of benign and malignant tumors.

The oncology includes 3 large divisions and numerous ultra-specializations; the 3 divisions are medical oncology, surgical oncology and radiotherapy oncology; among the various ultra-specializations, however, include, among others: gynecological oncology, hematological oncology, gastrointestinal oncology and senological oncology.

A practicing oncology is a category of specialized doctors, known as oncologists or medical oncologists.

What is Oncology?

Oncology is the branch of medicine that deals with the diagnosis, treatment and prevention of benign and malignant tumors.

Oncology is a subject of study for a category of specialized doctors, known as oncologists or medical oncologists .

What is a Tumor: a fundamental review

To fully understand what oncology is and what it includes, it is necessary to review what tumors and other aspects are related to these dreaded health conditions.

• A tumor is a mass of abnormal cells, indicated by the expression "transformed cells", whose rate of division and growth is, due to a loss of control mechanisms, higher than the parameters considered normal.

  Simply put, a tumor is a mass of cells that grow in an uncontrolled way .

  The onset of a tumor is the result of a series of cellular DNA mutations, which alter the genes responsible for controlling the processes of cell division, growth, maturation and death.

• A tumor is said to be benign, when the abnormal cells of the mass that constitute it present a division rate and growth moderately higher than normal, they lack the ability to invade adjacent tissues and, finally, they are unable to reach the bloodstream.

  In other words, a benign tumor is a mass of cells with abnormal behavior, by division and growth, but which are not invasive for the surrounding tissues and not even infiltrating the blood.

• A tumor is called malignant, when the abnormal mass cells that constitute it have a much higher rate of division and growth than normal and are capable of affecting the surrounding tissues and spreading to the rest of the body, after their passage in the blood (metastasis ).

  In other words, a malignant tumor is a mass of cells with extremely abnormal behavior, which, by virtue of the behavior of its cells, is invasive for adjacent tissues and infiltrating the blood.

• As can be deduced also from the descriptions just reported, malignant tumors are decidedly more dangerous conditions than benign tumors, which, however, deserve the due attention, as they could evolve into malignant formations.
• Responsible for the death of 7.4 million people worldwide, malignant tumors represent the leading cause of death on a global scale (13% of the world's deaths are attributable to them).

  Among the most common malignant tumors are: lung cancer, stomach cancer, breast cancer, colon cancer (or colorectal cancer) and liver cancer.

• The word "tumor" has a synonym: neoplasia .
• Malignant tumor is also known as: malignant neoplasm and cancer .

What are the tasks of the oncologist?

The oncologist is the doctor who has the task of investigating the diagnostic findings related to a tumor, trying to establish the stage of progress and the severity, and, based on these insights and the patient's state of health (age, presence of other diseases, etc.), plan the most appropriate therapy.

Focused on the so-called tumor biopsy, the in-depth studies related to a tumor represent, for the oncologist, an obligatory and indispensable step, without which it is impossible to base a potentially valid and effective therapeutic path.

The oncologist makes use of various collaborators - including the anatomopathologist, the radiologist and the oncologist nurse - who help him in diagnostic research and in the implementation of the therapeutic plan.

Origin of the word "Oncology"

The term "oncology" comes from the ancient Greek; it is, in fact, the fruit of the union of the words " ogkos " ( ὄγκος ; in Italian we read "oncos") and "logos" ( λόγος ), which mean, respectively, "tumor" or "mass" and "study".

Thus, the literal meaning of "oncology" is "tumor study".

Divisions

The oncology includes 3 major divisions, which are: medical oncology, surgical oncology and radiotherapy oncology .

Medical Oncology: what is it?

The expression "medical oncology" defines that oncology sector that is interested in the pharmacological therapy of tumors, namely the treatment of tumors based on the use of drugs.

The drugs used to fight tumors are generally called "anticancer drugs" and include: chemotherapy, oncologic immunotherapies, medicines for so-called molecular target therapy (or targeted therapy ), hormones and hormonal antagonists .

Among the useful drugs to fight tumors, include:

Surgical Oncology: what is it?

The expression "surgical oncology" describes the oncology sector which is dedicated to the surgical removal of tumors and to the taking of tissue samples for biopsy.

Oncology Radiotherapy: what is it?

The expression "radiotherapeutic oncology" and its synonym "oncological radiotherapy" define that oncological sector that deals with the treatment of tumors by means of radiotherapy, that is the form of treatment based on the use of ionizing radiation .

Specializations

Today's oncology offers the possibility for doctors who practice it to ultra-specialize and acquire specific skills in the diagnosis, treatment and prevention of a very specific category of tumors.

The list of ultra-oncological specializations is articulated and includes, among others:

• Gynecological oncology : deals with the diagnosis, treatment and prevention of tumors of the female genital tract, ie tumors of: ovaries, cervix, endometrium, vulva and vagina.
• Hematologic oncology : is dedicated to the diagnosis, therapy and prevention of blood cancers, ie: leukemia, lymphoma and myeloma.

• Breast oncology : deals with the diagnosis, therapy and prevention of breast cancer.
• Neuro-oncology : is dedicated to the diagnosis, treatment and prevention of brain and cerebellum tumors.
• Gastrointestinal oncology : is dedicated to the diagnosis, treatment and prevention of tumors in organs such as: stomach, small intestine, colon, rectum, anus, liver, gall bladder and pancreas.
• Bone and musculoskeletal oncology : deals with the diagnosis, treatment and prevention of bone, muscle and soft tissue tumors of the joints.
• Dermatological oncology : is dedicated to the diagnosis, treatment and prevention of skin cancers (eg, squamous carcinoma, basal cell carcinoma, etc.).

Diagnosis

For the diagnosis of tumors, modern oncology uses:

• Imaging tests (or imaging ). Among the most well-known imaging exams useful for the detection of tumors, include: ultrasound, X-rays, magnetic resonance, CT, PET and bone scintigraphy.

  Among the tumors identifiable by imaging tests, the tumors in organs such as, for example, lungs, brain, uterus, ovaries or pancreas, and bone tumors deserve a mention;

• Endoscopy examinations . Endoscopy is a diagnostic method that involves exploring from inside an organ included in the thorax or abdomen, through a special probe, previously inserted through a natural opening in the human body (mouth, anus or urethra).

  Endoscopy includes numerous techniques for exploration from inside the thoracic and abdominal organs; among these techniques, the main ones are: gastroscopy (for the vision of the esophagus, stomach and the first part of the intestine), colonoscopy (for colon vision), rectoscopy (for viewing the rectum), laryngoscopy (for the vision of pharynx, larynx and throat in general), bronchoscopy (for trachea and bronchial tree vision) and cystoscopy (for bladder vision).

  Endoscopy techniques are procedures that involve a certain preparation and the use of anesthesia (as they are painful or annoying); furthermore, they are not exempt from adverse effects and complications;

• Blood tests and bone marrow tests . Blood tests and bone marrow tests are the basis for the diagnosis of blood cancer; moreover, the blood tests are useful for the identification of the so-called tumor markers, ie those particular biomolecules (generally proteins) which, in the presence of a given tumor, are present in concentrations higher than normal;
• Tumor biopsy . The tumor biopsy consists in the collection and subsequent analysis in the laboratory of a sample of cells belonging to a tumor.

  The tumor biopsy is the only diagnostic test that allows to confirm the presence of a tumor and, at the same time, to establish the stage of progress of the current neoplastic condition.

  Tumor biopsy can be a diagnostic examination characterized by a certain invasiveness; in fact, in the presence of certain tumors, in fact, doctors must resort to an endoscopy technique, needle aspiration or real surgery for the execution of the sampling.

Therapy

To combat tumors, today's oncology can count on drugs, surgical methods and radiotherapy.

Antitumor drugs

The most important anticancer drugs are:

• The chemotherapeutic drugs . They are medicines that have the ability to recognize and kill rapidly growing cells, such as the cells that characterize tumors.

  The list of chemotherapy drugs is very broad and includes various subcategories of drugs, including: alkylating agents (eg cyclophosphamide, cisplatin and carmustine), antimetabolites (eg: methotrexate and cladripine), cytotoxic antibiotics (eg: daunorubicin) and antimitotic agents (eg: vinblastine and vincristine).

The anticancer therapy based on the use of chemotherapy drugs is called chemotherapy .

• Oncological immunotherapies . They are basically derivatives of cells or proteins of the human immune system, able to recognize cancer cells and attack them, until they are destroyed. The mechanism of recognition is based on the presence, on the outside of the cell membrane of tumor cells, of specific molecules, which are absent in healthy cells (it is as if the cancer cells presented a mark, which the oncological immunotherapists are able to recognize) .

  Some of the most well-known oncologic immunotherapies are monoclonal antibodies (eg: rituximab, trastuzumab, bevacizumab, cetuximab, panitumumab and ipilimumab), interleukin 2 and interferon-alpha .

The antitumor therapy focused on the use of oncological immunotherapies is called oncological immunotherapy .

• Drugs for so-called targeted therapy (or molecular target therapy). They are medicines that specifically counteract anything that promotes the growth and development of cancer cells; more in detail, they attack, destroying or defusing them, some molecules (usually receptors on the cell surface) that cancer cells use to grow and replicate.

  Examples of drugs for so-called targeted therapy are the so-called tyrosine kinase inhibitors (eg imitinib, gefitinib, erlotinib, bortezomib and sorafenib) and the so-called serine / threonine kinase inhibitors (eg: everolimus and temsirolimus).

Monoclonal antibodies act similarly to tyrosine kinase inhibitors and serine / threonine kinase inhibitors (they also interfere with molecules that cancer cells use to grow replicate), therefore they can also be included in the category of drugs for so-called targeted therapy .

• Drugs for so-called anticancer hormone therapy . Hormone antitumor therapy stems from scientific observation that the growth of some tumors (eg breast cancer) is affected by the levels of sex hormones circulating in the blood.

  The drugs for this type of anticancer therapy are hormones or hormonal antagonists, which have the task of interrupting the hormonal mechanisms necessary for the tumor to grow.

  Some examples of drugs for anticancer hormone therapy are: androgens, antiandrogens, estrogens, antiestrogens, corticosteroids, progestins and thyroid hormones .

Cancer Surgery

Surgical oncology is a very broad area, which includes many types of surgery and different techniques for performing them .

In general, the purpose of cancer surgery (or anticancer surgery ) is the total elimination / removal of the tumor from the training site.

However, unfortunately, this purpose is not always feasible and this leads to the so-called recurrence, that is the reappearance of the tumor.

IS IT ALWAYS APPLICABLE?

Antitumor surgery is not always applicable; to hinder its implementation can be:

• A late diagnosis . In such situations, malignant tumors have reached such dimensions that removal would lead to the elimination of a considerable part of the attacked organ;
• The uncomfortable position . The growth of a tumor in an uncomfortable position prevents the surgeon from reaching the abnormal mass and providing for its removal;
• The delicacy of the affected organ . Intervening on some organs of the human body (eg: brain) can cause more damage than good in the presence of certain tumors.

WHEN IS IT MORE EFFECTIVE?

Surgical oncology is all the more effective, the more the diagnosis is early (because the size of the tumor is still contained) and the more the tumor is in an accessible position (because greater accessibility to the tumor mass facilitates the removal work ).

Tumor Radiotherapy

Tumor radiotherapy is the anticancer therapy that provides direct exposure of tumors to a certain dose of ionizing radiation, with the final aim of destroying the neoplastic cells.

In general, the practice of tumor radiotherapy is combined with another type of anticancer therapy, as the mere exposure of the tumor to ionizing radiation is not sufficient to hope for a cure; the choice to associate cancer radiotherapy with chemotherapy or antitumor surgery depends on the type of tumor present, it is solely up to the attending oncologist.

Prevention

Given the number of deaths worldwide due to cancer, the prevention of these diseases is a very sensitive and debated topic.

Modern oncology promotes two types of cancer prevention, both of which are very important, which are: the so-called primary prevention of cancer and the so-called secondary prevention of cancer.

Primary Cancer Prevention

In oncology, when doctors talk about primary prevention, they refer to strategies to prevent the appearance of tumors .

The strategies for the primary prevention of tumors concern the adoption of a healthy lifestyle, therefore:

• Not smoking;
• Do not exceed alcohol consumption;
• Eat healthy and balanced foods;
• Avoid sedentariness.

Secondary Cancer Prevention

In oncology, the expression "secondary prevention" refers to the strategies useful for the so-called early diagnosis of tumors, namely the recognition of tumors when they are still in their very first stages or when the nature of their cells is still not totally altered.

The strategies for secondary cancer prevention correspond to cancer screening tests .

A screening test is a diagnostic test that allows to identify, in a group of people considered at risk for a specific disease, those subjects who have a high probability of suffering from the aforementioned pathology; in this way, those at risk may be subjected to more detailed investigations and possibly early / preventive therapy.

In other words, a screening test is a check performed to identify, among the potential targets of a given pathology, the possible future patients, so that they can be addressed early to more specific investigations and, possibly, to appropriate therapies.

It is important to point out that the execution of a screening test is not based on the presence of symptoms, but only and exclusively on the belonging of an individual to a group of people at risk for a certain disease. This means that screening tests are also provided for apparently healthy and healthy people.

Oncology focuses on screening tests especially in the field of breast cancer prevention ( mammography ; breast cancer), colorectal cancer ( occult blood research in faeces ; gastrointestinal oncology) and cervical cancer ( pap test ; gynecological oncology).