Can cancer be inherited or infectious?

At the cellular level, cancer is the result of genetic mutations that drive uncontrollable cell growth. These mutations can either be inherited or acquired over a person's lifetime. Inherited mutations are present in the germ cells (sperm and egg) and can be passed on to the next generation, while acquired mutations occur in the cells of the body during one's lifetime and are not passed on to offspring.

Factors such as environmental exposure (e.g., to UV light and carcinogens), lifestyle choices (e.g., tobacco use), and random errors during cell division can lead to acquired mutations. When mutations occur in genes that control cell growth and repair, they can lead to cancer. Notably, having a genetic predisposition due to an inherited mutation does not mean an individual will definitely develop cancer; it only indicates a higher risk. It is the combination of inherited susceptibility and external factors that often leads to the development of cancer.

Understanding genetic mutations is crucial for cancer prevention and treatment, as it enables doctors to provide personalized medical advice and treatments tailored to an individual's unique genetic profile.

The term 'oncovirus' refers to viruses that can lead to the development of cancer in infected individuals. These viruses can trigger genetic changes in cells, turning them cancerous. The process often involves the virus inserting its genetic material into the host's genome, disrupting normal cell functions and promoting uncontrolled cell growth.

While cancer caused by oncoviruses is not contagious, the viruses themselves can be transmitted between individuals through various means, including sexual contact, blood-to-blood contact, and, in some cases, saliva. Immunization programs, like the HPV vaccine, have been pivotal in reducing the incidence of virus-induced cancers by preventing infection. Thus, although cancer cannot be 'caught' from someone else, comprehending how oncoviruses operate is key to cancer prevention strategies. It is important to note the distinction between the infectious agent (the virus) and the condition it may cause (cancer), as this underscores the role of preventive healthcare measures.

The BRCA1 and BRCA2 genes are crucial for repairing DNA damage and maintaining genomic stability. Mutations in these genes can significantly elevate an individual's risk of breast and ovarian cancers, among others. Inheriting faulty copies of either the BRCA1 or BRCA2 gene does not guarantee that cancers will develop, but it does represent a genetic predisposition.

These gene mutations can be detected through genetic testing, which is especially important for individuals with a family history of related cancers. Knowing one's BRCA status can guide decision-making in terms of surveillance, preventive measures, and treatment options. In some cases, individuals may opt for prophylactic surgeries, like mastectomy or oophorectomy, to significantly reduce the risk of developing cancer. Furthermore, this knowledge has implications for family planning, as there is a 50% chance of passing the mutation to one's children. Counseling and education are important for individuals with BRCA mutations to navigate these complex personal and medical decisions.