Tumor Suppressor Genes

A 35-year-old woman from Mumbai presents with bilateral breast cancer diagnosed at age 28 and 32 years. Her mother died of ovarian cancer at age 45. Genetic testing reveals a germline mutation in a tumor suppressor gene. Which gene is most commonly mutated in this hereditary cancer syndrome?

Which of the following best describes the mechanism by which loss of the APC tumor suppressor gene leads to colorectal cancer in familial adenomatous polyposis?

A 35-year-old woman is found to carry a germline mutation in the TP53 gene. Which syndrome is she at risk for, and what is the characteristic feature of this inherited cancer predisposition?

A 5-year-old boy with a history of unilateral retinoblastoma (diagnosed at age 2) now presents with a new orbital mass. Which investigation is most appropriate to confirm the diagnosis and assess for bilateral disease?

A 45-year-old man with hereditary retinoblastoma (RB1 mutation carrier) develops bilateral retinoblastoma. Which agent is the preferred first-line systemic therapy to preserve vision while treating the intraocular disease?