Radiology Monthly

Thursday, June 1, 2017

Coronary Artery Calcium Score may serve as guide for the treatment of Hypertension

A study by McEvoy et al published in Circulation determined that computed tomography of the heart used to detect coronary artery calcium levels (CAC) can assist in the creation of treatment plans for patients with high blood pressure.

Their study tracked 3,733 people whose mean age was 65 years and had a systolic blood pressure between 120 and 179 mm Hg. During the study period that tracked the enrolled patients for over 10 years 642 events were detected.

The researchers found that patients with calcium scores of zero who were at high risk of arteriosclerotic heart disease (ASCVD) their incidence of a heart attack or stroke was low. While patients with systolic blood pressure lower than 140 mm Hg and a low risk of heart disease that had a CAC of more than 100 their incidence of a heart attack or stroke was higher.

The authors concluded that CAC scoring and assessment of arteriosclerotic vascular disease may guide in the determination of selecting as a goal to achieve the traditional 140 mm Hg or a lower systolic blood pressure such as 120 mm Hg particularly among patients with an estimated ASCVD risk of 5-15% and prehypertension or mild hypertension.

Monday, May 1, 2017

Sonographic criteria in the diagnosis and treatment of appendicitis.

According to a study by Xu et al published in the Journalof Ultrasound in Medicine ultrasound can provide information regarding the preferred treatment i.e. proceed with appendectomy or try antibiotics first in patients with appendicitis.

The authors reviewed retrospectively sonographic studies of 119 patients with histopathologically proven appendicitis. The diagnostic criteria and the preferred treatment in patients with suspected appendicitis was the presence or absence of the normally echogenic submucosal layer, the presence of mural hyperemia, periappendiceal fluid, appendicoliths, and hyperechoic periappendiceal fat and the maximum outside diameter.

Thirty-two (27%) of the 119 patients had complicated appendicitis, including 11 with gangrenous appendicitis without perforation and 21 with gangrenous appendicitis and perforation. Loss of the submucosal layer was the only independent significant indicator of complicated appendicitis (P < .001) and provided sensitivity and specificity values of 100.0% and 92.0% respectively.

The researchers concluded if loss of echogenic submucosal layer was detected at sonograpy the diagnosis of complicated appendicitis was likely and, therefore, surgery was necessary. On the other hand, when ultrasound did not show loss of the submucosal layer, antibiotic therapy should be tried, as the likely diagnosis is uncomplicated appendicitis.

Saturday, April 1, 2017

MRI and TRUS biopsy in prostate cancer

A paper by Ahmed et al published in the Lancet suggests a quarter of men suspected of having prostate cancer could avoid potentially dangerous biopsies with the help of MRI scans.

The authors did a multicenter study and tested the diagnostic accuracy of Multi-parametric MRI (MP-MRI) and Transrectal ultrasound guided prostate biopsy (TRUS-biopsy) against template prostate mapping biopsy (TPM-biopsy). Men with prostate-specific antigen concentrations up to 15 ng/mL, with no previous biopsy, underwent 1·5 Tesla MP-MRI followed by both TRUS-biopsy and TPM-biopsy.

The researchers enrolled 740 men, 576 of who underwent 1·5 Tesla MP-MRI followed by both TRUS-biopsy and TPM-biopsies. Results from TPM-biopsy showed 408 (71%) of the men had cancer, including 230 (40%) men with clinically significant cancer. When evaluating the 230 men with clinically significant cancer, the MP-MRI had correctly diagnosed 93% of the aggressive cancers, whereas TRUS-biopsy diagnosed only 48% as aggressive. This indicated that MP-MRI was more sensitive than TRUS-biopsy (P < .0001). Of the 10 men with a negative MP-MRI scan, nine (89%) had no cancer or a harmless cancer.

However, TRUS-biopsy had greater specificity (96% vs. 41%) and positive predictive value (90% vs. 51%; P < .0001 for both) than MP-MRI. Forty-four (5·9%) of 740 patients reported serious adverse events, including 8 cases of sepsis following biopsy.

This study shows that using the two tests could reduce overdiagnosis of harmless cancers by 5%, prevent one in four men from having an unnecessary biopsy, and improve the detection of aggressive cancers from 48% to 93%.

In conclusion given that prostatic cancer which is the most common cancer in men with about 176,000 new cases and the cause of death in 27,000 patients in the United States in 2013, MP-MRI is a promising diagnostic test in the effort to reducing over-diagnosis of clinically insignificant prostate cancers while improving the detection of clinically significant cancers.

Wednesday, March 1, 2017

Low Dose CT Lung Cancer Screening

Research by Kinsinger et al published in JAMA Internal Medicine revealed that “low dose CT scans” frequently produce false positives and demand considerable effort by both patients and requesting physicians.

The US Preventive Services Task Force recommends annual lung cancer screening (LCS) with low-dose computed tomography for current and former heavy smokers aged 55 to 80 years.

This clinical demonstration study was conducted at 8 academic VHA hospitals among 93 033 who met the criteria for LCS, 2106 agreed to undergo screening (2028 were men and 78 women; mean [SD] age, 64.9 [5.1] years).

Wide variation in processes and patient experiences occurred among the 8 sites. Of the 2106 patients screened, 1257 (59.7%) had nodules; 1184 of these patients (56.2%) required tracking, 42 (2.0%) required further evaluation but the findings were not cancer, and 31 (1.5%) had lung cancer. A variety of incidental findings, such as emphysema, other pulmonary abnormalities, and coronary artery calcification, were noted on the scans of 857 patients (40.7%).

In conclusion the research, conducted in more than 2000 high-risk VHA patients aged 55 to 80 years found lung cancer in 1.5% of patients, but around 60% of individuals who were screened had 1 or more nodules that required follow up. In addition, incidental findings were reported in around 40% of patients. It is estimated that implementation of LCS in the VHA 6.7 million patients will lead to approximately 900000 patients being eligible for LCS and will require substantial clinical effort for both patients and staff.

Wednesday, February 1, 2017

How effective is screening mammography?

A study by Welch et al published in New Engl J Med added to the growing evidence that for every woman who was helped by screening mammography many have been harmed.

The authors used data from the SEER program from 1975 through 2012. They calculated the size-specific cancer case fatality rate in women 40 year old and older for two time periods: a baseline period before the implementation of widespread screening mammography (1975 through 1979) and a period encompassing 10 years (2000 through 2002).

Screening did result in more cancers being detected, with invasive tumors measuring <2 cm or in situ carcinomas increased from 36% to 68%; and the detected tumors that were large, which were invasive cancers and measuring ≥2 cm decreased from 64% to 32%. Surprisingly though the data suggest that only about 30 of the 162 additional small tumors per 100,000 women that screening mammograms found would ever have progressed to a dangerous stage. That means that 132, or 81 percent, of the 162 extra tumors detected represented overdiagnosis, that resulted to treatment of tumors that were never destined to harm.

Most importantly, the incidence of metastatic cancer, which is the type that causes most deaths, was flat.

In conclusion the findings from this study indicate that screening mammography finds many small cancers the dogma that all will grow, metastasize resulting in fatality is questionable. The authors also suggest that although screening may decrease cancer mortality as reflected by the declining incidence of larger tumors, they believe that the two thirds reduction in breast cancer mortality is due to recent advances in treatment.

N Engl J Med 2016; 375:1438-1447