MRI in Cirrhotic Patients at High Risk for Hepatocellular Carcinoma

Kim at al reported in JAMA Oncology their experience regarding the accuracy of MRI with liver specific contrast versus ultrasonography in the surveillance of patients with cirrhosis who are at high risk in developing hepatocellular carcinoma.

Ultrasonography (US) is considered the study of choice for screening patients with cirrhosis at risk of hepatocellular carcinoma.  The current recommendation is for US to be performed every 6 months.

Liver MRI was performed on a 1.5Tesla scanner and Gadoxetic acid (Primovist) was administered at a dose of 0.025 mmol/kg.  Axial T1 weighted images of the arterial, portal, delayed and hepatobilliary phases at 4-mm thickness sections were obtained.   

The authors conducted a prospective study of 407 cirrhotic patients who underwent semi-annual US and MRI studies.  The patients were followed with dynamic computed tomography 6 months after the screening imaging studies.

A total of 407 patients received 1100 screenings with both MRI and US.  Hepatocellular carcinomas were diagnosed in 43 patients.  Ultrasound diagnosed only one HCC, MRI detected 26, 11 by both, and 5 were missed by both.

The HCC detection rate of the MRI was 86%, higher than the 27.9% of US.  MRI showed significantly lower false-positive findings than US, 3% versus 5.6% of US.  Of the 43 patients with HCC 32 had a single less than 2 cm nodule and received curative treatments.  The 3-year survival of the patients with HCC (86%) was at par to those without HCC.

The 5-year survival rate of HCC is lower than 20%, and early diagnosis is essential for the possibility of a cure.  The current recommendation for patients at high risk of developing HCC is US needs to be reviewed as the  accuracy of US is low.

The authors conclude that screening of patients with cirrhosis with MRI and liver specific contrast resulted in higher HCC detection rate and fewer false positive findings when compared with US.

JAMA Oncology, Online First, September 22, 2016

Digital breast tomosynthesis may reduce recall rates

JAMA Oncology published McDonald et al research regarding the efficacy of digital breast tomosynthesis (DBT) on recall rates versus that of digital mammography (DM), and also its sustainability over the long term.

The study was a retrospective analysis of a total of 44468 screening events performed on 23958 women whose average age was 56 years and were followed over a period of 4 years.

Recall rates rose slightly for years 1 to 3 of DBT (88, 90, and 92 per 1000 screened, respectively) but remained significantly reduced compared with the DM zero rate of 104 per 1000 screened. The cancer cases per recalled patients continued to rise from DM zero rate of 4.4% to 6.2% for years 1 to 3 of DBT, respectively. Outcomes assessed for the most recent screening for individual women undergoing only 1, 2, or 3 DBT screenings during the study period demonstrated decreasing recall rates of 130, 78, and 59 per 1000 screened, respectively (P < .001). Interval cancer rates, determined using available follow-up data, decreased from 0.7 per 100 women screened with the use of DM to 0.5 per 1000 screened with the use of DBT.

Digital breast tomosynthesis screening outcomes are sustainable, with significant recall reduction, increasing cancer cases per recalled patients, and a decline in interval cancers.

Elderly undergo cancer-screening tests that may not be necessary

Abdollah et al report in a JAMA Oncology article their findings that suggest some older individuals undergo screening tests for breast and prostate cancer despite the fact that those tests aren’t recommended for them.

The investigators looked at data from 149 514 individuals, 65 years or older selected among those who responded to the Behavioral Risk Factors Surveillance System Survey and resided in the United States. The primary outcome was non-recommended screening, defined as receipt of prostate-specific antigen (PSA) testing or mammography in individuals with a life expectancy of less than 10 years.

Of the 149 514 individuals, 76 419 (51.1%) had a PSA test or mammography in the past year; 23 532 (30.8%) of those individuals had a life expectancy of less than 10 years, corresponding to an overall rate of non-recommended screening of 15.7% (23 532 of 149 514 individuals).

Significant state-by-state variation in the rate of non-recommended screening was observed. Moreover, non-recommended screening at the state-by-state level had a correlation of 40% between the 2 forms of screening (P = .01). Therefore, a state with a high rate of non-recommended screening for prostate cancer is likely to have a high rate of non-recommended screening for breast cancer and vice versa.  The extent and variation of non-recommended screening across states, fluctuated from 11.6% in Colorado to 20.2% in Georgia.

The authors suggest that efforts should be made to reduce non-recommended screening as such scheme may reduce harms to individuals from false positives, and decrease the cost to the US health system from overdiagnosis that may be as high as $1.2 billion annually therefore improve the overall efficiency of screening initiatives.

Editor’s note:  The authors maybe are underestimating the cost to the US health system.  According to the US census individuals over 65 were 14.5% in 2014.   This percentage corresponds to 46 million in a total population of 318 million.  If we consider that the cost of mammography is $120 and of the PSA blood test $80 then the cost to the US health system could be as high as 4.6 billion dollars annually.