Prostate cancer: When will we have a reliable prostate cancer screening system for men, and when we do, how will we treat those many cases of early-stage prostate cancer that are detected?
Are we inching closer to a “ManoGram”? Rolf Taylor contemplates the current landscape – and the potential for increased research funding in the near future.
1 in 6 men will face prostate cancer in their lifetime, and each year it will kill 28,000 men in the U.S. alone. But unlike breast cancer, for which outcomes have improved dramatically as a result of near universal mammograms and advances in treatment options, prostate cancer remains stubbornly under diagnosed. Patients with rising PSA levels who show signs of malignancy don’t want to risk doing nothing, but can’t be sure that they definitely need treatment. And surgery carries major risks including erectile dysfunction and incontinence. Many patients need a blood transfusion during surgery.
It’s a perplexing situation: we can’t say definitively if a detected abnormality is cancerous. PSA ing is not definitive. Ultrasound is not definitive. MRI images are not currently definitive. Even diagnostic needle biopsy is not definitive.
Yet after surgical removal of the whole gland (radical prostatectomy) biopsies show that for as many as 45% of patients, the surgery was unnecessary. These statistics are leading some American men to fly to Mexico to receive a non-surgical alternative which is yet to be approved by the FDA. Others elect “watchful waiting” in preference to an intervention that could have serious side-effects. An excellent recent article by Melinda Beck in the Wall Street Journal details many of these issues, and a follow-up article weighs some of the treatment options.
So what would a happier situation look like?Early and accurate diagnosis should detect the disease before it has spread. Better diagnostic techniques should be able to show if the tumor is benign, or slow growing, aggressive, or has metastasized. Treatment would be then be matched to reality – so that the guess work is taken out of the equation. This raises the possibility for focal (localized) treatment, where only those areas that are cancerous are treated, leaving the prostate - and the patients quality of life - intact. This would open the door to highly accurate focal modalities such as focused ultrasound to be used routinely in the early stages. These treatment modalities also have great potential for pain palliation and the ablation of secondary tumors in later stage disease.
At the recent ISMRM Annual Meeting there were some clear signs of progress. Researchers are using the diverse capabilities of MRI and PET-MR to seek a more definitive diagnosis. In addition to the growing use of 3 Tesla MRI, MR spectroscopy enables the identification of high choline levels, and as presented by John Kuranewicz and reported by Zhang et al, can detect metabolites such as lactate and alanine from hyperpolarized carbon 13-labeled pyruvate. It seems likely that early accurate diagnosis will be dependent on the development of MRI techniques, not the least expensive procedure, but perhaps the imaging modality most likely to provide consistent accuracy. Separately, there were a presentations reporting advances in MR-guided focused ultrasound technology for prostate treatment, for speeding up the MR thermometry which guides the treatment, and for delivering a drug payload directly to the tumor site. For more details see my report in the FUSF Newsletter due mid-May, you can register here. These advances are happening through the more sophisticated utilization of existing technology as a result of research time and effort. Logically, the more we can invest in this type of research, the faster we can advance.
The AdMeTech Foundation coined the term “Manogram” to bring attention to the need for medical imaging techniques for men that detect prostate cancer early. They are part of a major lobbying process which aims to provide research dollars specifically targeting the need to improve medical imaging for prostate cancer. Last month Senator Barbara Boxer reintroduced the PRIME (Prostate Research Imaging and Men’s Education) Act to provide $650 million over 5 years for research to improve prostate diagnostics, including imaging and in vitro ing. This, in addition to the stimulus package, represents a major opportunity to make the “Manogram” a reality through a concerted research initiatives. If you can support this bill please do so. If we can see prostate cancer, we can treat it. And with noninvasive treatments such as MR guided focused ultrasound on the horizon, there is every reason to be optimistic about demoting prostate cancer from its current position as the second most lethal malignancy after lung cancer.