The Health Service Executive has been advised that it should not fund the use of two new cancer drugs due to their cost.
The recommendation from the National Centre for Pharmacoeconomics concerns a breast cancer drug called Perjeta made by Roche and a drug for lung cancer called Xalkori made by Pfizer.
The evaluation said Perjeta significantly increases the average survival for patients, but the true estimate of the gain is uncertain at this time.
It is used for women with metastatic or locally recurrent breast cancer who have not received certain previous therapy or chemotherapy.
The NCPE assessment sought by the HSE puts the cost of this drug at €74,000 per patient for an average 18-month treatment.
This would mean a cost to the HSE of around €39m over the next five years.
Possibly around 130 patients in Ireland might benefit from the drug.
NCPE said a significant price reduction would be needed to ensure value for money.
In the case of the drug Xalkori, for adults with previously treated advanced non-small cell lung cancer the treatment cost would be almost €50,000 per patient for over seven months.
Around 16 patients might benefit from treatment this year.
The cost over five years to the HSE would be over €6.2m.
NCPE has said the drug has been shown to improve quality of life, but not yet an overall survival benefit.
At its current price, it said the drug cannot be recommended as a cost-effective treatment option as the health benefit does not justify the price.
In recent years, after a negative recommendation by NCPE, talks between the Department of Health, the HSE and pharmaceutical firms have resulted in a reduced price agreement and some drugs being provided by the HSE for patients.
Pfizer Healthcare Ireland, which makes Xalkori, said it will await a decision from the HSE on whether it will fund the lung cancer drug.
The company said the 2012 drug supply agreement, between the State and the pharmaceutical industry, stipulates that medicines that do not reach a cost-effectiveness threshold should be subject to additional scrutiny and assessment - not that they should not be reimbursed.