GPs need better support in prescribing medicines that lower the risk of certain cancers, according to a new study by Cancer Research UK, published in the British Journal of General Practice.

The research assessed GPs' knowledge on prophylactic use of tamoxifen in women at high risk of breast cancer and aspirin in people with Lynch Syndrome, a condition that raises the risk of several types of cancer.

NICE has recommended that tamoxifen be considered to prevent breast cancer among women with a clear family history of the disease since 2013, but the report found that only just over half of the 1,007 surveyed across the UK were aware the drug could be used in such a way.

Moreover, just 24 percent were knew of the NICE familial breast cancer guidelines while just a fifth of Scottish GPs were aware of similar guidelines from Healthcare Innovation Scotland.

However, the report reveals that despite this low level of awareness, more than three-quarters of GPs were willing to prescribe tamoxifen, while "many" would be more comfortable if they knew a secondary care clinician had written the first prescription, the charity noted.

Conversely, a relatively high proportion - 73 percent - of GPs were aware that aspirin can reduce the risk of bowel cancers in people who are not at high risk, but among those who had heard of Lynch Syndrome, just under half knew the drug can cut the risk of cancers linked to the condition.

"Our report helps us to understand GP attitudes towards the use of cancer preventing drugs," said Dr Samuel Smith, author of the report and a Cancer Research UK fellow at the University of Leeds, commenting on the findings. "It's clear that more needs to be done to promote the evidence and guidance associated with these drugs, particularly as research reveals GPs are lacking the support to discuss effectively the risks and benefits of preventive therapy."

"Cancer-preventing drugs have the potential to have a huge impact by reducing the risk of cancer developing in the first place. This report reveals that it's vital that GPs are given the right support and information so they are confident to explore the value of these drugs with those who would benefit from them, wherever they are in the UK," added Professor Arnie Purushotham, CR UK's senior clinical adviser.

The report is calling on NICE and NHS England and its peers to promote the evidence and existing guidance on chemoprevention along with the potential benefits and harms of these drugs, and makes a number of other recommendations to help ensure that cancer prevention drugs are routinely discussed with and offered to those who could benefit from them.

Responding to the research, Professor Helen Stokes-Lampard, chair of the Royal College of GPs, noted that "with clinical guidelines rightly being updated so frequently and given the incredibly broad spectrum of knowledge GPs need to have, it's understandable that family doctors often take cues from our specialist colleagues in hospitals - so improved communication channels between primary and secondary care would certainly be helpful".

"Ultimately, any decision to prescribe drugs to patients must be the result of a full and frank conversation between doctor and patient, taking into account the latest clinical guidelines, considering all the positives and negatives, but also based on a patient's unique circumstances and family history in order to achieve the best possible health outcome for that patient," she stressed.