Multiple malignant tumors 

Most types of cancer are not caused by a single "mishap" in cellular proliferation and defense mechanisms. Rather, they are caused by the accumulation of a number of "mishaps" – some internal, some external. In this way, many tumors that may develop throughout our lifetime are naturally prevented, however, for this very reason, the risk for developing cancer later on in life increases. As we age, we are exposed to an ever-growing number of internal "mishaps" and external environmental factors.

A number of tumors arising simultaneously or within a short period of time in a young individual, or a large number of malignant tumors diagnosed in immediate family members demands ruling out of an inherent, inherited increased risk for developing cancer.

There are a number of hereditary syndromes which put their carriers at an increased risk for developing malignant tumors. Diagnosis of these syndromes, through genetic testing, reflects the carrier's increased risk and enables monitoring at frequent intervals in order to promptly diagnose tumors at potentially curable stages.