Discovering New Genetic Markers in Adults and Children Who May Be At Risk for Hereditary Forms of Cancer

Inclusion Criteria: * Individuals who have undergone clinical and/or research genetic evaluation, found to have or not have a germline genetic variant (pathogenic, likely pathogenic, variant of uncertain/unknown significance, likely benign). * Individuals with or without a personal history of malignant or pre-malignant lesions who demonstrate: a) clinical findings suggestive of a genetic cancer susceptibility syndrome including very early age at onset, multiple primary malignancies, or other features; and/or b) family histories suggestive of a genetic cancer susceptibility syndrome, or c) other features suggesting inherited etiology of malignancy as determined by the PI. * Family members of the above participants. Both children (with parental consent as age appropriate) and adults are eligible to participation. * Individuals may or may not be enrolled MSK patients; probands may be referred to (or self-referred to) the study and may be enrolled at discretion of the PI and if able to provide informed consent. * Biospecimens derived from deceased family members may be used for research in this study if consent if provided by the executor of the estate of that individual. Exclusion Criteria: * Patients will be excluded from this study if he/she has physical, cognitive or psychiatric conditions that interfere with ability to give meaningful informed consent.