IF YOU were a cancer patient, how much would you want to know about your treatment options? Would you rather know only the basic, and trust the oncologist to recommend what's best for you?

Questions like these were the focus of an organised 'debate' by several colorectal cancer specialists and oncologists at a major European oncology conference this week.

 
The topic is especially relevant now, given the availability of the KRAS (pronounced as kay-ras) test to find out which subtype of colorectal cancer a patient has. KRAS is a gene that plays a role in how a cancer is developed and progresses. There are different types of KRAS genes - either 'wild-type' or 'mutant' - and these indicate the response to certain drugs.

As an oncologist puts it, they no longer view colorectal cancer just as generic cancer, but as subtypes of a cancer. 'There is a huge change in the way we look at patients. And with the notion that therapy will be linked to specific treatments, we see patients in molecular subgroups,' says Prof Sabine Tejpar of the University Hospital Gasthuiserg in Belgium.

With targeted treatments now available, there's a shift in the treatment paradigm as patients now have to make informed decisions, says Dr Heinz-Josef Lenz from the University of Southern California.

Especially so as new and different treatments do come with side effects still - even if results are promising.

Merck Serono, which organised the debate, also released the results of its latest studies on Erbitux, its targeted colorectal cancer drug which works mostly on patients with KRAS wild-type tumours.

Two new studies have shown that overall survival rate with the combined use of Erbitux and chemotherapy can be extended by up to four months, while risk of disease progression reduced by 34 per cent.

In Singapore, colorectal cancer patients can request the KRAS test to be performed on a sample of tumour tissue. Results can be obtained in about a week, Kong Hwai Loong of the Medical Oncology Clinic tells BT.

Saving time and money

'In the old days, we mainly distinguished cancers between the colon and rectum. But now, we're dividing them based on molecular biology. What used to be confined to the science labs now has an impact on oncology practice,' he adds.

So now, doctors know before giving a drug whether it's going to work on the cancer or not. 'You don't waste time or money on a treatment 'hoping' that it'll work.'

KRAS testing has been around for a year-plus in Singapore but many doctors don't know of it yet, not to mention patients, says Dr Kong. 'I'd expect information like this to take three to five years to percolate down to the medical community. It's still 'upstream' knowledge at this point,' he notes.

Part of the reason for that is that cancer is a complex field, even for other doctors or specialists in other fields, so it's difficult to grasp the advances in the last few years. 'And among specialties, oncology is one of the specialties growing by leaps and bounds. There's immediate interaction between laboratory sciences and clinics, so much so that within a year, practices change,' Dr Kong explains.

Twenty years ago, when patients didn't have much access to information, doctors simplified explanations to them, but the doctor-patient relationship is now seen more like a partnership. 'It's important that oncologists spend time communicating with their patients so that they make informed decisions. It's no longer a luxury, but a necessity,' he concludes.

Besides colorectal cancer, the other two cancers whose profiles are changing rapidly due to molecular definitions are breast and lung cancer, points out Dr Kong. As for colorectal cancer tests, he says that everyone diagnosed with this cancer should take the KRAS biomarker test. 'It's not too expensive - just over $200 - but it's an important test that can save several thousands of dollars for the patient, as well as time.'