I'm hedging my bets here, as I don't want to condemn the living to a premature death, and am not bucking to scoop Mark Evanier on this in a competition to be the industry's death-watching comic book ghoulunatic, and am a respectful fan of Kamen's work. I'm hoping it's not true, afraid it likely is, wonder if anyone else has heard anything.
For those who don't know (for shame, doc), Kamen is usually noted as the "pretty girl" specialist at E.C., often being handed romantically-themed stories and the less gruesome material in the horror books, often revolving around "widdle kids" or lovely fashion model-type heroines on the edge, going mad and murderous, or getting murdered off-panel or in a more wholesome manner than his fellow artists at the publisher often depicted (although every once in a while he turned out something appropriately nasty and surprising).
He's also the father of Dean Kamen, the inventor of the Segway, among other things.
Anyway, if it's true, R.I.P. Jack Kamen.