Genetic Diagnostics for Oncological Diseases

An oncological disease is one of the most challenging diagnoses, capable of disrupting or even claiming a patient’s life. However, advancements in medicine now offer methods for early diagnosis and personalized therapy, significantly increasing the chances of prevention and successful treatment.

Hereditary forms of malignant neoplasms arise due to an inherited mutation in one of the gene copies passed down from parents. Such mutations can be transmitted to future generations, creating conditions for the transformation of a normal cell into a malignant one.

Two hereditary (germline) factors contribute to genetic risk:

• Rare harmful changes, often referred to as “pathogenic variants” or “mutations,” that impair the function of a known gene. For example, pathogenic variants such as BRCA1/2 are rare in the population but are associated with a high lifetime risk of cancer (high penetrance).
• More common variants, known as single nucleotide polymorphisms (SNPs), can directly affect gene regulation or function. SNPs are relatively common (frequency above 1% in the population), but each individually contributes a small increase to the risk of oncological conditions.

Genetic diagnostics are performed for the following purposes:

• Assessment of individual cancer risk: Enables the identification of hereditary predisposition to specific types of tumors long before their onset, facilitating a personalized approach to screening for early detection and/or prevention of tumor development.
• Targeted medical surveillance: Individuals with mutations can undergo regular monitoring (e.g., early and regular breast cancer screening, colonoscopy, MRI, etc.).
• Decision-making for prevention: Including preventive surgical interventions (e.g., mastectomy for BRCA1/2), lifestyle changes, or pharmacological prophylaxis.
• Treatment planning for cancer patients: Identifying mutations helps select optimal targeted or immunotherapy approaches.
• Risk assessment for relatives: A detected mutation may be inherited, so family members can also be tested to determine the need for monitoring or prevention.
• Confirmation of hereditary syndromes: Establishing a diagnosis (e.g., Lynch syndrome, Li-Fraumeni, FAP) with a subsequent personalized approach to patient management.