Friday, 26 June 2009

JNCI response to latest attack on screening by Grotzche et al

JNCI response to latest attack on screening by Grotzche et al

In a very balanced editorial in today's JNCI, Liz Savage writes about the recent letter to The Times of London, and the claim that up to 50% of cancers are diagnosed unnecessarily by the NHS Breast Screening Programme (NHS BSP), but primarily the attack was again on the content of invitation leaflets sent to women at each invitation. These were changed or amended after their last attack in the media a few years ago.

Although some of their criticism remains valid, their wild claims that 50% of cancers detected by screening would never kill women remains unsubstantiated.
While it is clear, that some women have an exceptionally good prognosis, and probably would never have had disease that would have killed them, the majority (or even if it was just the 50%) would definitely have been helped.

Newer genomic typing of tumors may assist at an early stage of diagnosis (perhaps at initial core biopsy) which group of risk she is in, then if low, she may not need any treatment, or just hormone therapy instead of the current more invasive procedures.

Typing, such as that used by mammaprint (nl), may be able to distinguish between three separate groups, with minimal overlap. Laura Vantveer, on sabatical with UCSF from Holland is developing this technique on all our cancers treated at UCSF. The middle group of women with less aggressive subtyping and the ones most likely to be helped by screening, the high risk women showed marked aggressivity at any size, and appear to need everything (including the kitched sink) thrown at them, to get a response (CPR - complete pathological response)

Women with the least aggressive subtype, may be represented by this group who never progress to a 'killer' cancer, and may be overtreated by being offered chemotherapy, radiotherapy or even surgery. If these cancers NEVER kill anyone, maybe a different term - other than carcinoma - may need to be used to indicate that these are a different disease compared with the real cancers.

These are interesting times, and allow us to start thinking more intelligently about screening, and the outcomes from screening. In the meanwhile.... let's get back to ensuring that women are adequately informed about the benefits and risks at their invitation.