Introduction and objective:
Hereditary cancers account for 5–10% of all neoplastic diseases. The most common are breast and ovarian cancer, and colorectal cancer. The aim of this study was to assess society‘s knowledge about the hereditary determinants of cancer, the most common hereditary cancers, and attitudes towards genetic testing.

Material and methods:
The study involved 200 people aged between 18–75. A diagnostic survey method with the use of an original questionnaire was applied. The obtained data were analyzed using Statistica 13.3 software.

Results:
The respondents demonstrated low knowledge about the heredity of cancer (45.3% of correct answers), and a positive attitude towards genetic testing for cancer. The respondents’ general knowledge was higher than the knowledge regarding specific types of cancer, especially colorectal cancer (32.6% of correct answers). Those who completed or were in the process of completing a medical degree showed greater knowledge and more positive attitudes than those not in the medical field. Those with higher education demonstrated more positive attitudes than those with vocational education. Respondents with suspected hereditary cancer in their family showed a more positive attitude towards genetic testing than those with no hereditary cancer in their family, but did not have more knowledge

Conclusions:
The respondents’ general knowledge concerning the inheritance of cancer is low, and education is necessary, especially in terms of features suggesting the carrier state of mutations that increase the risk of the most common hereditary cancers. The level of knowledge is higher among people with medical education. The respondents have a positive attitude towards the genetic testing of cancer, especially those with higher or medical education and those who have a family history of cancer.