Cancer

Cancer is a marine Vice Admiral.

Appearance
Cancer is a man with slicked-back grey hair, sunglasses, and is often seen with a cigar in his mouth. He has a scar running down his left eye. Cancer wears a brown suit under a Marine coat.

In the anime, during the Marineford Arc, Cancer was shown with black hair.

Personality
As a Marine, he strongly believes in Justice, though whether he believes in moral justice or absolute justice is not known yet.

Abilities and Powers
As a Marine vice admiral, Cancer is capable of commanding a Buster Call alongside other vice admirals. He also has authority over lower-ranking subordinates.

Haki
It was stated that all vice admirals possess Haki, so Cancer can also use the ability. However, he has not been shown using it.

East Blue Saga
Cancer was first seen sitting next to Vice Admiral Stainless at the meeting about Luffy's first bounty.

Jaya Arc
He attended the meeting held at Mariejois to discuss Crocodile's Shichibukai replacement. Doflamingo used his body manipulation ability to make Vice Admiral Mozambia and Vice Admiral Stainless fight each other. Cancer wanted to stop Mozambia, but Doflamingo's manipulation was too strong.

Marineford Arc
Cancer was seen behind Vice Admiral Stainless and Vice Admiral Doberman, along with his fellow vice admirals, lined up and ready to fight the Whitebeard Pirates. Later, he was seen alongside Vice Admiral Tsuru, and was shocked when it was revealed that the Whitebeard Pirates had hidden another ship below the bay.

One Piece Film: Z
Cancer was seen at the new Marine Headquarters, attending a meeting alongside other strong Marines about former Admiral Z destroying the first Endpoint in the New World.

Major Battles

 * The Marines and Shichibukai vs. Whitebeard Pirates and Allies

Anime and Manga Difference

 * In the anime, he did not appear next to Stainless in the meeting about Luffy's first bounty.
 * In Episode 151, he doesn't have his scar.