Helen Henwood has beaten cancer. Now she is trying to win against her travel insurance company.

Mrs Henwood, 64, was diagnosed with bowel cancer days before an overseas holiday and had to cancel the dream trip.

But her travel insurance company has refused to refund the cost of the $18,000 holiday, claiming the tumour was a "pre-existing condition".

The bowel cancer was found five days before the Masterton widow and grandmother of six was to leave with a tour group in August last year.

She had been feeling abdominal pain, but an ultrasound check in March found nothing.

Her doctor declared her fit to travel in May and signed a medical certificate for health and travel insurance forms.

But he referred Mrs Henwood to a specialist, who also found nothing remarkable, but ordered a scan.

That's when the tumour was found.

"The surgeon said: 'You're not going home, we're operating tomorrow'," said Mrs Henwood.

The cancerous nodes were removed in a four-hour operation the next day, ruling out the holiday.

Instead of enjoying a three-week trip through Canada and Alaska, Mrs Henwood began a three-month course of chemotherapy treatment in Palmerston North Hospital.

She assumed the nearly $18,000 cost of the cancelled trip would be covered by her policy with Mike Henry Travel Insurance.

But the firm said the cancer was a "pre-existing condition" under investigation which she had failed to disclose.

"But the cancer hadn't been diagnosed," says Mrs Henwood. "Nobody knew."

The Weekend Herald has obtained Mrs Henwood's medical records and correspondence from IAG New Zealand, the parent company of Mike Henry Travel Insurance.

A letter from GP Rob Maunsell confirms that Mrs Henwood did not have a pre-existing condition when she signed the insurance agreement.

Medical reports by specialist Richard Stein - dated July 30, 2008 - also found nothing remarkable but he ordered a further scan.

The treatment by Dr Maunsell was disclosed in the application for insurance cover. But as the referral to Dr Stein was not disclosed, the claim was declined, although he found nothing.

"At the time of taking out the insurance policy, Helen had a duty to disclose to us the fact that she had been referred by her GP to a specialist for investigation of her condition," says correspondence from IAG New Zealand. "This fact was material to the acceptance of the insurance."

IAG refused to discuss Mrs Henwood's case with the Weekend Herald, citing client confidentiality.

Sales and development manager Keri Collins said insurance policies could be extended to cover pre-existing medical conditions, but could not cover conditions under investigation.

After a year of fruitless talks, Mrs Henwood now plans to lodge a complaint with the Insurance and Savings Ombudsman. "I just feel like I've been hitting my head against the wall."