Eastern Health is apologizing to patients who received the wrong test results.

The health authority revealed Thursday that nine breast cancer patients were given wrong test results and needlessly treated with the drug Herceptin.

At a hastily-called news conference, Eastern Health CEO Vickie Kaminski apologized to those affected.

“This is a very distressing time for our patients and their families, and we are offering whatever support they need at this time," said Kaminski.

Eastern Health first noticed something unusual in December – but the nine were only identified this week after further testing by an external lab. The final results came back on Tuesday.

Eastern Health met with the patients Thursday and oncologists are following up with them.

Kaminski said it is a "very distressing time" for those affected and their families, and the health authority is offering whatever support they need.

“I am very sorry that this has happened to these nine patients,” said Kaminski.

So far, none of the patients have reported any negative side effects.