"ALK Deficiency" – What Is It?
ALK-related predisposition to neuroblastic tumors is caused by a genetic alteration in the ALK gene, indicating an increased risk of developing tumors originating from autonomic (involuntary) nerve tissue. These tumors include neuroblastomas, ganglioneuroblastomas, and ganglioneuromas, primarily occurring in infancy and childhood. Additionally, tumors of the adrenal glands may develop.
How is "ALK Deficiency" Diagnosed?
Clinical Diagnostics
The presence of an ALK-related predisposition to neuroblastic tumors is suspected in a person who has one of the following findings:
- Multiple primary neuroblastic tumors that co-occur or at different times
- Occurrence of neuroblastoma, ganglioneuroblastoma, or ganglioneuroma in more than one family member
Genetic Diagnostics
The diagnosis of “ALK-related Predisposition to Neuroblastic Tumors” is confirmed by detecting a mutation, i.e. a genetic change in the ALK gene.
How High Is the Risk of Cancer?
If a patient has a mutation, i.e., genetic change, in the ALK gene, the probability of developing a neuroblastic tumor is probably over 50%.
The risk of developing neuroblastic tumors is highest in infancy and decreases with increasing age. In familial neuroblastoma, tumors occur earlier (on average at the age of 9 months) than in neuroblastoma without familial clustering (on average at the age of 2-3 years).
In addition, there is an increased risk of multiple primary tumors in familial neuroblastoma compared to the non-familial form. These multiple primary tumors can be bilateral adrenal tumors or multiple primary tumors outside the adrenal glands that arise in the area of cell accumulations of the autonomic nervous system. The tumors can occur at the same time or at different times.
What Is Known About the Development of "ALK Deficiency "?
The ALK-related predisposition to neuroblastic tumors is based on a mutation, i.e., a genetic change in the ALK gene. This gene codes for the ALK protein, which is a specific receptor that controls the proliferation and development of immature nerve cells. If the gene is present in an altered form, the protein is no longer produced correctly and cannot perform its function properly, leading to the development of tumors.
Is There Any Form of Treatment Available?
Patients with ALK-related neuroblastic tumors should be treated in a pediatric oncology clinic. Here, the procedure is also coordinated with the neuroblastoma study management. There is currently no evidence that patients with ALK-related neuroblastic tumors tolerate chemotherapy or radiotherapy less well or react more sensitively to these therapies. In principle, the use of ALK inhibitors can also be considered.
Diagnosis of " ALK Deficiency" What's Next?
If you have been diagnosed with this cancer predisposition syndrome, it is important to see a specialist. The following section explains whether cancer screening tests or other measures are needed and how they should be carried out. We also give you some valuable tips on what you can do yourself. If you have any questions, please do not hesitate to contact us or your doctor.
Diagnose ALK Deficiency. Wie geht es weiter?
If you have been diagnosed with this cancer predisposition syndrome, it is important to see a specialist. The following section explains whether cancer screening tests or other measures are needed and how they should be carried out. We also give you some valuable tips on what you can do yourself. If you have any questions, please do not hesitate to contact us or your doctor.
Medical Measures for Early Detection
To date, there are no uniform recommendations. One possible procedure for the early detection of neuroblastic tumors with a known ALK mutation is as follows:
Clinical examination, ultrasound of the abdomen, measurement of catecholamines (messenger substances of the autonomic nervous system) VMS and HVS in the urine, X-ray of the lungs
- every 3 months for children aged 0-6 years
- every 6 months for children aged 6-10 years
- No screening is required for children > 10 years of age
After successful treatment of a neuroblastic tumor, early detection examinations should be continued until the age of 10 years due to the risk of developing multiple primary tumors.
ALK Deficiency- What You Can Do Yourself
What Should I Pay Particular Attention To?
In the event of new anomalies, complaints or other symptoms, you should urgently consult a doctor to clarify whether a neuroblastic tumor is present. The earlier this is found, the easier the treatment and the better the prognosis.
Since further, so-called multiple primary tumors can develop even after successful treatment of a neuroblastic tumor, early detection examinations should definitely be continued up to the age of 10.
Support Groups
Unfortunately, we are not yet aware of any support groups for patients with an ALK-related predisposition to neuroblastic tumors. As soon as we have new information, we will add it here. However, patients can register for the CPS registry at any time or have this done by their doctors.
Any Further Questions?
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