From the point of view of clinical genetics, genetic counselling could be defined as the educational process whose purpose is to help someone who is suffering from a genetic illness and/or their relatives who are at risk to understand the characteristics and consequences of the pathology, the probabilities of it happening to them or being transmitted, and the options for preventing or avoiding it. The recent important development in complementary diagnostic techniques, basically in cytogenetics and molecular biology, has favoured a new investigational focus on hereditary diseases and an important change in the very concept of human pathology, greatly facilitating genetic counselling.

Although it is known that there are some specific types of malignant tumours that occur in people with a certain genetic predisposition, it must be taken into account that despite the rapid advance that has been made in the past 10 years in this field, in many cases we do not know the specific gene that causes the problem, or else we know its location but not the specific mutation that is responsible for it.

Ideally, genetic counselling on hereditary cancer should be offered under certain circumstances: when the individual presents characteristics of his personal or family history that suggest a genetic susceptibility to cancer, when the available genetic test can be adequately interpreted and when the results can assist in the diagnosis, or influence the medical or surgical handling of the patient, or of family members with hereditary risks of cancer. The patient's independence and privacy must always be respected.

RISK FACTORS

Hereditary cancers represent only a small portion of all cancers, thus the number of individuals at risk is also small. Nevertheless, there is a series of indications which suggest the existence of the hereditary cancer syndrome, such as for example:

- Cancer in 2 or more members of the same family

- Diagnosis at an early age

- Multiple primary tumours

- Bilateral cancers, when the organ affected is a pair or double (e.g. the breast)

- Presence of various cancers in the same patient

- Constellation of tumours and other benign and/or malignant abnormalities compatible with a specific cancer syndrome (e.g. breast and ovary)

- Vertical transmission (i.e. from one generation to the next - from parents to children, for example) of the illness.

Reference: Cummings S. The genetic testing process: How much counselling is needed? J Clin Oncol 2000; 18 (21) Suppl: 60-64

HOW OUR CONSULTATION WORKS

The fundamental objective of this Consultation is to detect and offer counselling or genetic counselling to cancer patients and to those of their first-degree relatives where a significantly high risk is detected of the appearance of these tumours, and, ideally, in those where this genetic determination influences clinical handling.

Our expert consultants give Genetic Counselling after evaluating the risk, studying the family tree, carrying out genetic investigation and/or predictive genetic diagnosis as a basis for individual recommendations to mutation carriers. They also send the patient to the most suitable clinical services so that they can take charge of follow up and pertinent preventive actions, as well as potential support services, such as psychological support for the patient and his/her relatives, registration and follow up of detected cases, etc.

From a practical point of view, our genetic counselling on hereditary cancer consultation is carried out in two possible steps:

FIRST STEP: Study of the family tree

The personal and family history is recorded, to check that the indication criteria for the genetic study are fulfilled. The family tree is drawn up with at least three consecutive generations (with all relatives, healthy and affected, age when cancer was diagnosed and date and cause of death). Cancer diagnoses must be confirmed by medical and histopathological reports. The probability of detecting a gene causing predisposition to hereditary cancer in the family will be evaluated through the family tree.

• If the criteria of indication for the genetic study are not fulfilled, the attention is terminated and the consultant is informed in writing about general preventive measures. A report will be made out for your G.P.
• If the criteria are fulfilled for some of the entities which are the purpose of the genetic counselling, the objectives and the process to be followed will be explained. By studying the family tree, the family can initially be classified into one of the three established risk groups:
  
  
  • Low risk families (risk equivalent to that of the general population): these receive information about the recommended preventive measures in general, and a report is drawn up for the G.P.
    
    
  • High risk families, but where a defined hereditary syndrome is not identified with this family unit. These are invited to participate in a DNA bank of a Hospital Unit, for analysis when future scientific advances come about. They are given psychological support. They are given information about the preventive measures recommended to the general population and those which are specific to their family history.
    
    
  • High risk families for a defined hereditary syndrome, where it is possible to recognise the responsible gene. A report is sent setting out the basic concepts of genetics, as well as the risks, benefits and limitations of genetic determination and the significance of the "positive" and "negative" results. The report also includes the cost of the tests to be carried out in such a case. In this report, the possibility of carrying out of a genetic study is offered:

    a) If they decide not to have the genetic study they are offered an approximate estimation of their risk and they are given information about specific prevention measures for the suspected syndrome.
    
    b) If they accept the genetic study, it would be carried out in a specialised molecular biology laboratory.

SECOND STEP: Genetic Study

It is desirable to begin the genetic study with the "index" case, and it is carried out by analysing blood samples. Occasionally, the genetic study may take several months due to the complexity of the technique. As a result of these analyses, the result of the genetic study is explained in a full report and the family are asked to inform us of any changes in the family cancer tree that may modify the recommendations. The results may be of three types:

• No mutation identified: the significance of the result is explained. Individualised preventive recommendations are given.


• A genetic alteration is identified, the pathogenic significance of which is not established: the significance of the result is explained. Individualised preventive recommendations are given.


• A mutation is identified: Information is given on the estimated risk of cancer associated with this mutation. The possible prevention alternatives are explained (intensive vigilance, prophylactic surgery, preventive medical treatment) and the most suitable option is recommended. The risk for other carrier relatives is also explained, in case they wish to get in contact with us. Clinical follow up of these people is carried out in a hospital unit recommended by us, co-ordinated by the selected specialist, who would be contacted and to whom the corresponding report would be sent and the necessary contact would be maintained with him for updating and adapting follow up recommendations and prevention.

 

Study of the family tree: €300 ($380)
Genetic Study: variable, according to the analysis to be done.
Request: info@cancer-consultants.com

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