“Two new studies published on Wednesday of patients with breast and prostate cancers add to growing evidence that detecting bits of cancer DNA circulating in the blood can guide patient treatment.
“Enthusiasm is building for ‘liquid biopsies,’ which offer a non-invasive alternative to standard tissue biopsies and are expected to be a multibillion-dollar market.
“But a key question remains: Do they really work?
“The stakes are high. At least 38 companies are working on liquid biopsies for cancer, according to analysts at investment bank PiperJaffray, who think the U.S. market alone could eventually reach $29 billion a year.”
“Premenopausal women diagnosed with breast cancer following biennial mammograms appeared more likely to have larger and more advanced tumors than women screened annually, according to the results of a prospective study.
“However, the proportion of tumors with less favorable prognostic characteristics appeared similar among postmenopausal women with breast cancer not treated with hormone therapy who received biennial or annual mammograms.
“ ‘The frequency at which women should receive screening mammography remains controversial in the U.S.,’ Diana L. Miglioretti, PhD, professor of biostatics at University of California, Davis, and colleagues wrote. ‘However … mammography accuracy has improved, new breast cancer treatments have been developed, and interest in tailoring screening recommendations to individual risk to maximize the balance of benefits vs. harms has increased.’ “
“It’s a good idea to keep an eye on your moles, to see if any of them are changing, which can be a sign of skin cancer, experts agree. But a new study finds that the sometimes-deadly skin cancer melanoma usually arises in normal skin, where there is no dark spot or sign of cancer until the melanoma suddenly shows up.
“Moreover, melanomas that arise in non-mole areas of the skin tend to be more aggressive and deadly than those that do arise from moles, the study found.
” ‘We find that the ones without a [mole] appear to be more aggressive,’ said Dr. David Polsky, the study’s lead researcher and a professor of dermatology, pathology and dermatologic oncology at New York University School of Medicine. ‘We think that there are biological differences’ between melanomas that develop within moles and those that develop elsewhere on the skin, and it’s possible that these differences underlie the difference in aggressiveness, he said.”
“What to do about the non-invasive breast lesions called ductal carcinoma in situ, or ‘stage zero’ cancer, is one of the hottest debates in breast cancer care.
“Because of more widespread screening, more and more women are being diagnosed with DCIS. The condition now makes up 20 percent of new breast cancer cases, according to the American Cancer Society.
“DCIS doesn’t always progress to invasive breast cancer, which is the life-threatening kind. In fact, some physicians and researchers, including a working group convened by the National Cancer Institute, say it’s not accurate to call DCIS a form of cancer at all, and that the terminology is contributing to overly aggressive treatment.”
“Mammograms at 40 or 50? Every year or every other year? What’s the best colon check?
“Screening for cancer has gotten more complicated in recent years with evolving guidelines that sometimes conflict. Now a doctors’ group aims to ease some confusion — and encourage more discussion of testing’s pros and cons — with what it calls advice on ‘high-value screening’ for five types of tumors.
“Too often, even the doctors who order those tests aren’t sure of the latest recommendations, said Dr. Wayne J. Riley, president of the American College of Physicians, which published the advice Monday in the journal Annals of Internal Medicine.
” ‘We want to make sure that folks get the right test at the right time for the right conditions,’ Riley said. ‘We also want our physician colleagues to try to avoid the customary, knee-jerk reaction to just test without having some sort of dialogue’ about the right choice for each patient.”
“A new study offers help to patients and doctors who are trying to deal with mammogram results that many women consider troubling and confusing: the finding of ‘dense’ breast tissue.
“Not only is breast density linked to an increased risk of cancer, it also makes cancer harder to detect because dense tissue can hide tumors from X-rays. But the new research indicates that not all women with dense breasts are at very high risk.
“Patient advocates urge women with dense breasts to ask doctors about extra tests like ultrasound or an M.R.I. to check for tumors that mammography might have missed. Studies have found that those exams can improve detection of tumors over mammography alone in dense breasts.
“Pressed by advocacy groups, 22 states have passed laws requiring that breast density be reported to mammography patients, and similar federal legislation has been introduced in the House and the Senate.”
“Biopsy guided by a fusion of magnetic resonance imaging (MRI) and ultrasound (US) improves detection of aggressive prostate cancer compared with mapping or targeting alone and systematic 12-core biopsy.
“Among the first 1,000 men to undergo MRI-fusion biopsy of the prostate at the University of California Los Angeles (UCLA), the presence of a grade 5 region of interest on fusion biopsy was the strongest predictor of high-grade prostate cancer. ‘Patients who had a grade 5 lesion compared to those who had no suspicious lesions had 23 times the odds of having Gleason ≥7 cancer,’ said Christopher Filson, MD, at UCLA.
“In a separate series of men presenting for prostate biopsy at New York University (NYU), MRI-targeted biopsy increased the detection of Gleason ≥7 prostate cancer by 23% compared with systematic biopsy while decreasing the detection of Gleason 6 disease by 26%.
“The American Cancer Society estimated that 220,800 new cases of prostate cancer will be diagnosed in the United States in 2015. Approximately 27,540 men will die of the disease, accounting for 5 percent of all cancer deaths.
“A common treatment for prostate cancer is a prostatectomy, in which all or part of the prostate gland is removed. Recent studies have shown that this procedure is often over-prescribed. As early as 2010, the New England Journal of Medicine reported that such a procedure extended the lives of just 1 patient in 48. Side effects from the surgery, including urinary incontinence and impotence, can affect the quality of life of the patient.
” ‘For every 20 surgery procedures to take out the prostate, it is estimated that only one life is saved,’ said Gabriel Popescu, director of the Quantitative Light Imaging Laboratory (QLI) and senior author on the study. ‘For the other 19 people, they would be better left alone, because with removing the prostate, the quality of life goes down dramatically. So if you had a tool that could tell which patient will actually be more likely to have a bad outcome, then you could more aggressively treat that case.’ ”