The Cortical Neuroanatomy Related to Specific Neuropsychological Deficits in Alzheimer's Continuum

BACKGROUND AND PURPOSE: In Alzheimer's continuum (a comprehensive of preclinical Alzheimer's disease [AD], mild cognitive impairment [MCI] due to AD, and AD dementia), cognitive dysfunctions are often related to cortical atrophy in specific brain regions. The purpose of this study was to investigate the association between anatomical pattern of cortical atrophy and specific neuropsychological deficits. METHODS: A total of 249 participants with Alzheimer's continuum (125 AD dementia, 103 MCI due to AD, and 21 preclinical AD) who were confirmed to be positive for amyloid deposits were collected from the memory disorder clinic in the department of neurology at Samsung Medical Center in Korea between September 2013 and March 2018. To analyze neuropsychological test-specific neural correlates representing the relationship between cortical atrophy measured by cortical thickness and performance in specific neuropsychological tests, a linear regression analysis was performed. Two neural correlates acquired by 2 different standardized scores in neuropsychological tests were also compared. RESULTS: Cortical atrophy in several specific brain regions was associated with most neuropsychological deficits, including digit span backward, naming, drawing-copying, verbal and visual recall, semantic fluency, phonemic fluency, and response inhibition. There were a few differences between 2 neural correlates obtained by different z-scores. CONCLUSIONS: The poor performance of most neuropsychological tests is closely related to cortical thinning in specific brain areas in Alzheimer's continuum. Therefore, the brain atrophy pattern in patients with Alzheimer's continuum can be predict by an accurate analysis of neuropsychological tests in clinical practice.

Never-Smoker Lung Cancer Is Increasing

PURPOSE: Lung cancer has been the leading cause of death in South Korea since the year 2000. Adenocarcinoma became the most frequent type in the national survey of lung cancer since year 2005. MATERIALS AND METHODS: We analyzed 5,456 cases with lung cancer from 2004 to 2012 in a community cancer center. The mean age was 69.9 years, and 78.9% was male. RESULTS: Adenocarcinoma (ADC, 40.8%) was the most frequent type, followed by squamous cell carcinoma (SQC, 36.4%), small cell carcinoma (SCC, 14.8%) and non-small cell lung cancer (NSCLC) not otherwise specified (8.1%). In male patients, SQC was the most frequent type (43.5%), while ADC showed highest incidence in females (72.6%). Anatomic stage at diagnosis in NSCLC was I (10.3%), II (5.8%), IIIA (15.7%), IIIB (19.2%), and IV (49.0%). In SCC, 41.7% was in limited stage and 58.3% was diagnosed in extensive stage. The proportion of never smoker has been increased from 19.1% in 2004~2008 to 25.4% in 2009~2012. Never-smokers are more likely to be female (68.2% vs. 4.0%, p<0.001), have ADC (69.9% vs. 31.3%, p<0.001), and manifest as stage IV disease (58.5% vs. 45.2%, p<0.001), compared to smokers. Among 1,908 cases whose initial treatment was recorded, 42.5% received chemotherapy, 25.7% received radiation treatment, 20.5% received surgery and the remaining 11.3% received supportive cares only or transferred to other health care facilities. CONCLUSION: In conclusion, proportion of lung cancer in never-smoker is increasing. As screening for smokers will miss this growing population, we need to discover biomarkers to find high risk population of lung cancer.