需否主動上報保險公司

所有保險公司的人壽、醫療、危疾計劃都會在客人投保時要求申報個人和近親已存在的病患與健康狀況（部分計劃會豁免健康申報），正如你所講，因某些疾病會有遺傳機會，所以要客人申報已知的病歷，以決定接受申請、加價還是拒絕客人投保。假如保單在審批期間投保人健康狀況有變，便需要通知保險公司以作考慮。但當保單生效後又過了各項保障的等候期（通常1-6個月，視乎保障而定），客人便無需再就等候期後發現的疾病（投保人或家人）再向保險公司申報，而保障是一直會生效至保單到期為止。除非客人另買新單，便要從新申報現時健康狀況。

Very simple - did you provide your family's medical information when you first applied?

If yes, then provide. Otherwise, no.

2013-02-21 18:35:33 補充：
Again - same question - Did you provide your family's medical information?

If yes, then provide. Otherwise, no.

The key is here - your family member has cancer. It does not mean you have cancer.

You may have a higher risk, but not always.

2013-02-21 18:36:16 補充：
For example, cancers induced from bad habits (smoking, alcohol, etc.)