SYDNEY, March 22, 2010 (AFP) - An Indian-born surgeon charged with causing the deaths of three Australian patients and injuring another pleaded not guilty to charges of manslaughter and grievous bodily harm on Monday.

Jayant Patel, 59, formally denied the charges concerning patients in his care when he was director of surgery at northern Australia's Bundaberg Base Hospital between 2003 and 2005.

Patel was extradited from the United States to answer the highly-publicised charges in July 2008, and arrived at the Brisbane city courthouse Monday with his wife, also a doctor.

Prosecutor Ross Martin told jurors the patients died or were maimed after Patel performed a series of unnecessary and poorly executed surgeries, including a "useless" operation performed after he misdiagnosed cancer.

One of the patients, 75, died after Patel removed part of his bowel without investigating the cause of his anal bleeding, while a 48-year-old nearing kidney failure never regained consciousness following oesophageal surgery.

"Without adequate consultation or consideration of the alternatives, the accused performed an operation called an oesophagectomy," Martin said.

"(The patient) never regained consciousness and died a few days later."

Patel botched the same surgery on the third patient, aged 77, and failed to realise he was suffering ultimately fatal internal bleeding.

"The accused either did not accept it was happening or chose to do nothing about it," Martin said.

Another patient was left with a colostomy bag for life after Patel removed his bowel on suspicion of cancer, despite a negative biopsy, the court heard.

Former patients turned out to watch the beginning of the Supreme Court trial, with a support group spokeswoman saying it had taken "five years of hard, hard yards to get it to this point."

"From here we'll just put our faith in the justice system and see where it takes us from there," said the spokeswoman, Beryl Crosby.

Up to 160 witnesses are expected to be called during the 10-week hearing, which will also be broadcast live to Bundaberg's courthouse.