Which type of cancer is easiest for to treat?

The One Prevented: The best way to cure a cancer is to identify who is at highest risk and take measures to prevent that cancer from developing. Prevention includes avoiding known carcinogens: our greatest cancer foe remains tobacco. Short of this goal, the next best strategy is to "screen" for cancer: widespread testing of at-risk populations before symptoms develop (mammograms, colonoscopy, prostate, etc).

BCC on the skin: Basal cell carcinoma of the skin can frequently be removed in the office under local anesthesia. If the margins are clear then you are usually cured of that lesion. Since sun exposure likely caused it, you are still at risk for developing skin cancers in the future, so get a head to toe skin check frequently.