Abstract
ObjectiveWe elected to analyze the correlation between the pre-treatment apparent diffusion coefficient (ADC) and the clinical, histological, and immunohistochemical status of rectal cancers.Materials and MethodsForty-nine rectal cancer patients who received surgical resection without neoadjuvant therapy were selected that underwent primary MRI and diffusion-weighted imaging (DWI). Tumor ADC values were determined and analyzed to identify any correlations between these values and pre-treatment CEA or CA19-9 levels, and/or the histological and immunohistochemical properties of the tumor.ResultsInter-observer agreement of confidence levels from two separate observers was suitable for ADC measurement (k = 0.775). The pre-treatment ADC values of different T stage tumors were not equal (p = 0.003). The overall trend was that higher T stage values correlated with lower ADC values. ADC values were also significantly lower for the following conditions: tumors with the presence of extranodal tumor deposits (p = 0.006) and tumors with CA19-9 levels ≥ 35 g/ml (p = 0.006). There was a negative correlation between Ki-67 LI and the ADC value (r = −0.318, p = 0.026) and between the AgNOR count and the ADC value (r = −0.310, p = 0.030).ConclusionSignificant correlations were found between the pre-treatment ADC values and T stage, extranodal tumor deposits, CA19-9 levels, Ki-67 LI, and AgNOR counts in our study. Lower ADC values were associated with more aggressive tumor behavior. Therefore, the ADC value may represent a useful biomarker for assessing the biological features and possible relationship to the status of identified rectal cancers.
Highlights
In recent years, colorectal cancer has become one of the leading causes of cancer-related death, while rectal cancer alone accounts for 30–35% of these cases [1]
Some studies have shown that the pre-treatment levels of carcinoembryonic antigen (CEA) and histological factors, such as tumor differentiation grade and the presence or absence of lymphatic vessel invasion are related to the overall prognosis [4,5,6]
Clinical and Histopathological Findings The tumor characteristics of 49 rectal cancer patients are listed in Tables 1 and 2
Summary
Colorectal cancer has become one of the leading causes of cancer-related death, while rectal cancer alone accounts for 30–35% of these cases [1]. Other immunohistochemical markers with established prognostic value include the following: 1) p53 and p21, which govern cell cycle checkpoints and apoptosis [9,10], 2) expression of CD44, which identifies cells that have lost their adhesion ability and/or have strong metastatic tendencies [11], 3) Her/neu, which influences cellular proliferation [12], and 4) the amount of AgNOR in a cell nucleus, which reliably reflects cell kinetics and can be used to assess the cellular proliferation rate; AgNOR counts increase with chronic inflammation, dysplasia, and malignancy [13] These prognostic markers are valuable in the evaluation of tumor specimens obtained at the time of surgical intervention. A method that will enable the pre-operative assessment of cancer with the eventual aim of better assessing prognosis has been long awaited and could be used to tailor individual patient treatment to better combat disease
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
