Fifteen years ago CSL Limited (ASX: CSL) earned under $50 million in profit. In 2013, it earned over $1.30 billion. Sirtex might not be as cheap as CSL was then, but the company's profits could follow a similar trajectory (though starting from a lower base). Where CSL supplies blood products, Sirtex Limited sells a treatment for liver cancer, a leading cause of cancer deaths worldwide. Both companies are concerned with saving lives. Back in 1999 CSL was less expensive than Sirtex is now, but Sirtex clearly belongs on any ethical investor's watchlist, and I regret not covering it sooner.