In our glossary you will find brief explanations of the most important terms used in clinical trials in cancer therapy.


not responding to a treatment/not treatable by the standard therapy

third-line therapy

Therapy that is used when the effect of a second-line therapy diminishes or its therapeutic success fails, e.g. a relapse occurs or metastases form

Adjuvant therapy

Additional treatment after full surgical removal of a tumour in order to prevent a recurrence

Adverse effects

Unwanted accompanying events that occur when a treatment is administered in the correct way


Acute lymphocytic leukaemia


From other people; e.g. allogenic bone marrow transplant


Partial or total hair loss; possible side-effect after chemotherapy or radiation of the head region.


Nicht mit einer Aufnahme ins Krankenhaus verbunden, im Gegensatz zu stationär


Acute myeloid leukaemia




Drug to prevent the urge to vomit; often used to prevent vomiting in patient having chemotherapy


Protective substances produced by the body to combat foreign substances.


Substance that triggers the formation of antibodies


Cell death that is controlled and actively triggered (programmed) by cells. The inhibition of apoptosis genes can lead to uncontrolled cell division and probably plays a role in the development of cancer.


Not harmful. Benign tumours respect the natural tissue boundaries, unlike malignant tumours. They can become very large, but do not penetrate neighbouring tissue and do not produce metastases.


Removal of a tissue sample for examination


Procedure used to ensure that mental influences and expectations do not distort the outcome of a study. In a blinded study (single- or double-blind study), the study participants do not know which study group they are in, i.e. whether they are receiving a new treatment or a placebo.

Bone marrow

Blood is formed in the bone marrow. Mature blood cells have a limited lifespan and so must be constantly recreated in the bone marrow.

Breast cancer

Malignant tumour in the breast


Causing or promoting cancer; substance that causes or promotes cancer


Malignant tumour that spreads from epithelial tissue, i.e. skin, mucous membrane or glandular tissue. Carcinomas are further differentiated according to the appearance and origin of the cells.

Carcinoma in situ

A tumour that is malignant in nature in terms of its cell composition but that is limited to a particular location, is not fast-growing, does not cross natural tissue boundaries and is not connected to the vascular system. It is a precursor stage of cancer.


Inhibiting the growth of tumour cells (cancer cells) in the body by the use of certain chemical substances, in particular drugs that inhibit cell division (cytostatics).


Carriers of the genetic material in the cell nucleus; they contain the DNA chain molecule. Normal human body cells have 46 chromosomes, but the number and/or structure of chromosomes can vary in the case of cancer cells.

Clinical study

Scientific investigations of people for people conducted according to strict medical and ethical rules. Their purpose is to obtain information in order to formulate better and more effective treatment recommendations.


Chronic lymphocytic leukaemia


Chronic myeloid leukaemia

Combination therapy

Therapy involving more than one drug or treatment method


The patient’s willingness to cooperate with diagnostic and therapeutic measures or to follow prescribed treatment.


Risk factor that distorts the results of a study or conceals the actual cause.

Consolidation therapy

Second treatment after induction therapy for leukaemia with the aim of destroying remaining cancer cells by means of chemotherapy or radiotherapy.


Condition or situation which means that a particular treatment is not advisable

Control group

Includes the study participants who are not receiving the new treatment but who, depending on the type of study, are receiving the standard treatment or standard procedure or a placebo.

Curative therapy

Treatment with the intention of curing the condition, in contrast to palliative therapy


Unit (of a treatment) that is repeated several times according to a schedule

Cytological diagnosis

Microscopic examination of cells from smears, blood or tissue samples (biopsies) to detect pathological changes

Cytostatic drugs

Non-endogenous substances that prevent the reproduction of tumour cells and often harm healthy cells in the process. Cytostatic drugs include both synthetic drugs and plant extracts.


Poisoning/damaging cells


Differentiation of tumour cells describes their similarity to or difference from normal cells of the organ in which the tumour has formed. Highly differentiated tumour cells are very similar to normal cells, while undifferentiated tumour cells are very different.


Desoxyribonucleic acid. Carrier of the genetic information of a living organism in the chromosomes in the cell nucleus

Double-blind study

A study in which neither the patient nor the study doctor know which patient is receiving which active substance (or placebo)


Malformation, deviation of the tissue structure from the normal situation. Dysplasias can be precursors of cancer.


Eine Studie, bei der die Patienten nicht wissen, welche Behandlung sie erhalten.


a method in which needles are inserted into the tumor so that short, powerful electrical pulses can be used to destroy tumor cells.


related to the hormone system


Measurement point in a study to determine, for example, the occurrence of a disease, a symptom or a lab value


A record of the frequency of new conditions (incidence), deaths (mortality), causes and risk factors


Über eine längere Zeitperiode fortgeführte Chemotherapie, die den Erfolg der Induktionstherapie und Konsolidierungstherapie bei Krebs stabilisieren soll.


Red blood cells

Ethics committees

High-level independent inspection bodies that assess the ethical and legal consequences of a study and ensure that study participants are protected.

First-line therapy

(sometimes called induction therapy, primary therapy, or front-line therapy) is the first therapy that will be tried


Emerging from a focus of disease


Hereditary factor, section of a molecule chain consisting of desoxyribonucleic acid (DNA). Genes are responsible for certain hereditary structures or functions of an organism.

Gene therapy

The insertion of genes into body cells to replace missing/altered genes in order to treat disease

Good Clinical Practice

International guideline for the proper conduct of a clinical study


The classification of tumours and tumour tissue according to their degree of differentiation. The figure (usually G1 to G3) describes how much the cancer cells differ from healthy, mature (differentiated) cells. This information is used to determine the malignancy of the tumour.


Relating to blood or blood formation


The science of the fine structure of body tissue


Chemical messenger substances formed in the body that reach their sites of action through the bloodstream. Hormones regulate growth, metabolism and reproduction, and can promote or reduce the growth of cancer cells.


Excessive, benign cell reproduction of tissue

Immune system

The body’s defence system, protecting it against pathogens. It eliminates micro-organisms like viruses, bacteria and fungi, and plays a part in combating endogenous or other pathogenic cells that have become defective.

Immune therapy

Form of treatment in which cells or messenger substances of the endogenous defence system are used to bring about a defence reaction against tumour tissue.


Der Begriff in-vitro bedeutet "im Reagenzglas" und bezeichnet Reaktionen ausserhalb des Organismus.


The term in-vitro means “within the glass" and denotes reactions outside the body


Frequency of new conditions, usually expressed per 100,000 residents per year

Induction therapy

The first step in cancer treatment, using chemotherapy or radiotherapy to try to reduce the size of the tumour, or the cell count in the case of leukaemia.


Invasive; in the case of tumours: spreading to surrounding tissue and destroying it

Informed consent

The voluntary consent (usually in writing) or study participants after they have been informed about the purpose, conduct, expected benefits and risks and their rights and responsibilities

Initial therapy

First treatment after diagnosis of an advanced tumour condition


Involving a number of different areas of specialisation

Intergroup study

Large study conducted by several research groups on several thousand patients.


Within a tumor

laser ablation

Procedure to remove tissue using a laser.


An impairment, change or injury to an organ or limb


Blood cancer; umbrella term for a type of cancer that occurs in the tissue that forms the blood (bone marrow). This is initially broken down into acute (rapidly progressing) and chronic (slowly progressing) forms of leukaemia. The division into myeloid or lymphatic leukaemias refers to the type of precursor cells that have become degenerate.


White blood cells


In a specific area


Cancer of the lymphatic system (lymph gland cancer). There are many types of lymphoma, which can be divided into two groups: Hodgkin’s lymphoma (HL) (usually restricted to the lymph glands) and non-Hodgkin’s lymphoma (NHL) (can occur almost anywhere in the body).


Harmful. In contrast to benign tumours, malignant tumours do not respect natural tissue boundaries but penetrate and destroy other tissue and can produce metastases in parts of the body far from their origin.


a diffusely growing tumor


Secondary tumours. These occur when cancer cells from the primary tumour are transported to other parts of the body via the bloodstream or lymphatic system. Metastases allow malignant tumours to be formed in other parts of the body.

Monoclonal antibodies

Proteins (immunoglobulins) that react with a single antigen. Researchers develop monoclonal antibodies that bond to specific antigens on the surface of the cancer cells in order to trigger an immune defence against these cells or to introduce a cancer-killing substance.


Treatment with a single drug


Likelihood of an individual developing a particular disease or condition


Proportion of deaths, normally expressed per 100,000 residents

Multi-centre study

Carried out at several hospitals (centres) at the same time

Multiple myeloma

Disease of plasma cells, which are a particular type of blood cell


Change in the sequence of building blocks in the DNA genetic molecule. Mutations can lead to changes or losses in the function of genes, and so affect the behaviour of cells.

Neoadjuvant therapy

Pre-operative treatment (e.g. chemotherapy) carried out before surgery to remove a tumour. It is designed to reduce the size of the tumour and/or kill off tiny tumour cell clusters.


Newly-formed abnormal cell growth, new formation, formation of new tissue, often malignant


Genes that are involved in the development of cancer. They are only carcinogenic if they have certain defects. Intact oncogenes have important regulatory functions in the cycle of cell division.


The study of the development, diagnosis and treatment of cancers. In the modern understanding, this also involves the care, after-care, psychological support and rehabilitation of patients.

Open study

Both the doctor and the patient know the study group to which the participant belongs.


Via the mouth

overall survival

The length of time from either the date of diagnosis or the start of treatment for a disease that patients diagnosed with the disease are still alive


An expression of statistical significance. A p-value of less than 0.05 means that the likelihood of the result being due to chance is less than 5%.


Treatment given to relieve the symptoms and reduce the suffering caused by cancer and other life-threatening diseases

Palliative therapy

Treatment aimed at relieving symptoms or preventing complications in the case of incurable cancers, in contrast to curative therapy


Causing disease, or a substance that does so


Related to disease


Doctor who investigates and assesses pathological changes to body tissues and cells.

Patient information

Informs patients about the purpose, intention, effects and side effects of investigations and treatments. Written patient information is always provided to complement the information given by the doctor if the treatment is planned in the context of studies.


Through the skin


Positron Emission Tomography. Computerised imaging procedure that produces images of cross-sections of bodily organs from which metabolic processes can be seen.


The study of the effects of drugs in the body, especially the profile of action, mechanism of action and the dose-effect relationship.


Description of the mechanism of action, i.e. the release, take-up, distribution, metabolisation and secretion of a particular drug.

Phase I study

First study in man; the search for new treatment methods that until this point have only been tested in the laboratory and in animal experiments.

Phase II study

Phase II studies investigate how effective and safe the new treatment is at the specified dose in combating a particular type of cancer.

Phase III study

The new treatment is compared to the usual method in order to find out whether the new treatment method is better.

Phase IV study

Rare side effects and interactions with other drugs are ascertained after the drug has been authorised for use.


A dummy drug that does not contain any active substance.

Placebo effect

Effects and side effects caused by a dummy drug for which there is no pharmacological explanation. The placebo effect is based on positive expectations and mental effects.

Preclinical tests

Tests carried out in the laboratory and on animals to thoroughly investigate a newly developed drug before the clinical phase and before use in humans.


Frequency of a particular condition at a particular time in a defined group, usually the entire population

Primary tumour

The tumour which developed first; in contrast to metastases


The advance of the disease


Reproduction of cells or tissue

Radical resection

Surgical removal of tumour, in which the entire organ and if necessary large sections of surrounding tissue are removed in order to ensure that tiny tumour cell clusters nearby are also captured.


Combination of chemotherapy and radiotherapy (at the same time or consecutively)


The use of short-wave, very high-energy radiation, alone or in combination with other measures, to combat malignant tumours.


A procedure followed in clinical studies, whereby participants are allocated at random to one or more treatment groups. The aim is to prevent the proven effect being subject to systematic bias.


Recurrence, reappearance of a disease


Decline of the disease. Complete or partial regression of the tumour, normally in response to treatment


Insensitivity to a treatment, e.g. of tumour cells to chemotherapy or of bacteria to antibiotics


Type of cancer starting in the bones, cartilage, fatty tissue, muscles or blood vessels


Early detection of diseases before they become apparent through symptoms

second-line therapy

Therapy that is applied when, after completion of the first treatment (first-line therapy), a therapeutic success fails, e.g. a tumour grows again or metastases form.


Importance; the difference between two treatments is significant if it is large enough that the study outcome cannot be due to chance.

soft tissue sarcoma

Soft tissue sarcomas are malignant tumors that originate in the soft tissue of the body such as muscles, tendons or fatty, connective and nerve tissue. 


A person, company, institution or organisation that is responsible for initiating, organising and/or funding the study.


The process of recording and classifying the local extent of the tumour, lymph node status and remote metastases (TNM classification) in order to find the most suitable treatment

Standard therapy

The conventional treatment whose efficacy has already been tried and proven. The best treatment available at the time.

Study arm

Patients are allocated to a study arm for a treatment that is to be investigated by comparison with another treatment. A study can include various study arms, e.g. an arm with a new treatment and an arm with standard treatment.


A healthy study participant

Supportive therapy

Prevention and treatment of complications and side effects of cancer therapy


Swissmedic, which is part of the Swiss Federal Department of Home Affairs, is responsible for the quality, safety and efficacy of drugs and medicinal products, and registers, approves and monitors all clinical studies carried out with drugs that are not routinely prescribed.

Toxicity, toxic

The poisonous effect of a substance, e.g. a cytostatic

Trial doctor

The doctor leading and conducting a clinical study. He/she is highly qualified and already has experience with clinical studies.


Swelling; in the strictest sense, a growth caused by the proliferation of cells that have escaped normal growth control; benign or malignant

Tumour markers

Endogenous substances that enter the blood in higher concentrations when cancer is present. They are used mainly to monitor the course of known cancers: a rise in tumour marker concentration in the blood can be a sign of tumour growth. Markers can also be detected in other bodily fluids and tissue.