A medical specialist has told a coronial inquest he would have recommended regular observation instead of wrongly diagnosing lung cancer and recommending surgery for a patient who later died — if a pathology sample had not been contaminated.

Broken Hill man Dennis "Jacko" Charles Jackson died from pneumonia in January 2019.

In the months prior, the 67-year-old had travelled to the Royal Adelaide Hospital (RAH) for a biopsy.

But his biopsy sample became cross-contaminated with the cancerous tissue of another patient at the SA Pathology laboratory, which led to Mr Jackson being incorrectly diagnosed with lung cancer.

He then underwent "unnecessary" surgery to remove part of his lung in August 2018 and sustained nerve damage during that procedure, leaving him unable to swallow, taste and smell.

Royal Adelaide Hospital thoracic medicine consultant Phan Tien Nguyen told the inquest that, if the pathology report had been accurate and concluded granuloma — an inflamed cell — rather than carcinoma, he would not have recommended surgery to remove part of Mr Jackson's left lung.

"Let's say there was no contamination, I would have recommended a CT scan in three months to assess the growth [of the nodule]," he said.

Professor Nguyen told the inquest he would have wanted to monitor Mr Jackson for two years as he was at a high risk of developing lung cancer.

He said the pathology report was consistent with Mr Jackson's medical history and symptoms, including his occupational exposure to dust and asbestos, history of smoking, location of the nodule in his upper left lobe and the 12-millimetre size of the nodule.

No disagreements over diagnosis

The doctor said no-one at a multi-disciplinary team meeting of RAH specialists held to discuss Mr Jackson's case raised any concern about the accuracy of the pathology report.

"I don't recall disagreement of the diagnosis," Professor Nguyen told the inquest.

Deputy Coroner Ian White asked if anyone at the meeting raised queries about the language used in the report, including "free-floating" tissue fragment.

"I don't believe so," Professor Nguyen replied.

"It seems that everyone at the meeting assumed that the report on the biopsy was accurate?" the coroner then asked.

"Yes," Professor Nguyen replied.

Professor Nguyen said he remembered Mr Jackson "quite well" and told the inquest his "unfortunate outcome" had prompted some change to practices at the hospital.

"As a result of this case, I think we pay more attention to a comment of 'free floating'," he said.

"Because the case has had a negative impact on all of us clinically … when we have seen that comment we have discussed the option of doing DNA on a sample to ensure.

"In those situations, we've been sure to check the other fragments in the biopsy."

The inquest also heard a RAH radiologist who undertook some of Mr Jackson's scans concluded that while malignancy could not be ruled out, Mr Jackson's condition was more likely a chronic granuloma condition.

The inquest before Deputy Coroner White continues.