Introduction. Hereditary tumor syndromes represent an important clinical and organizational challenge because they are associated with early onset of malignant neoplasms, multiple primary tumors and increased cancer risk among blood relatives. In routine oncology practice, timely identification of patients with clinical signs of hereditary predisposition is essential for referral to medical genetic counseling, molecular genetic testing and subsequent cascade screening. A primary oncology visit may therefore serve as a key entry point for selecting patients who require further genetic assessment. Aim. To assess the frequency of detection of clinical signs of hereditary tumor syndromes among patients with a newly diagnosed malignant neoplasm based on data from a multidisciplinary medical institution for the period from 2018 to 2024. Materials and methods. A retrospective medical organizational study was conducted at the A. S. Loginov Moscow Clinical Scientific Center. The analysis included data from 61,602 electronic medical records of patients with a first in life diagnosis of malignant neoplasm. Signs of suspected hereditary tumor syndrome were defined using clinical and anamnestic criteria. These included age from 18 to 50 years combined with one of the associated tumor types, including breast, colon, thyroid, gastric, prostate, pancreatic, ovarian, endometrial, kidney cancer or cutaneous melanoma, as well as the presence of multiple primary malignant neoplasms regardless of age. Descriptive statistics were used. Results. Clinical signs of hereditary tumor syndromes were identified in 8,692 patients, accounting for 14.1% of the total cohort. The annual proportion increased from 12.3% in 2018 to 15.5% in 2023, while in 2024 it was 14.4%. Breast cancer, multiple primary tumors and thyroid cancer predominated in the nosological structure, accounting for 31.8%, 25.9% and 13.3%, respectively. Discussion. The observed frequency exceeds the commonly cited range of 5–10% because it reflects the frequency of clinical and anamnestic suspicion rather than the prevalence of molecularly confirmed hereditary tumor syndromes. Thus, the proposed approach should be regarded as a clinical filter that defines the need for medical genetic counseling and subsequent molecular testing. Conclusions. A primary oncology visit can be used as an effective stage for active selection of patients with signs of hereditary tumor syndromes. The use of simple clinical and anamnestic criteria provides an organizational basis for molecular genetic testing, cascade diagnosis and preventive work with patients’ relatives.