Differentiation of prostate cancer in central gland with Histogram analysis of apparent diffusion coefficient
Xiaohang Liu1, Liangping Zhou1, Weijun Peng1, and Yong Zhang2

1Radiology, Fudan university shanghai cancer center, Shanghai, China, People's Republic of, 2MR Research China, GE healthcare, Beijing, China, People's Republic of

### Synopsis

The diffusion weighted imaging (DWI) is commonly used in the diagnosis of Prostate cancer, but the cancer in Central gland (CG) is considered harder to detected on conventional DWI,but histogram analysis of apparent diffusion coefficient could potentially improve the differentiation of prostate cancer in CG.

### Purpose

The diffusion weighted imaging (DWI) is commonly used in the diagnosis of Prostate cancer, but the cancer in Central gland (CG) is considered harder to detected on conventional DWI. The major obstacle to identifying CG cancer comes from stromal hyperplasia (SH), which showed a similar apparent diffusion coefficient (ADC) value with CG cancer. Thus the purpose of this work was to investigate apparent diffusion coefficient (ADC) of prostate CG cancer and SH with Histogram analysis, and to determine which ADC metric may help best in the differentiation between the two tissues.

### Materials and Methods

Twenty-eight CG cancer foci and 34 SH nodules in the CG were analyzed in 54 patients (24 with CG cancer, 30 with peripheral zone cancer but no CG cancer) who underwent preoperative DWI with single-shot spin-echo echo planar imaging (SS-EPI) sequence (b-value 0, 1000 s/mm2). All of the cancer and hyperplastic foci on MR images were localized on the basis of histopathologic correlation. The 10th , 25th and 50th and mean ADC value of the were calculated for all of the lesions. The efficiency of 10th, 25 th and 50th for the differentiation of CG cancer from SH was compared to ADC by Receiver operating characteristic (ROC) analysis.

### Results

The 10th , 25 th and 50th and mean ADC values (×10−3 mm2/s) were 0.87±0.13, 0.90±0.14, 0.96±0.15,1.06±0.16 in SH and 0.63±0.12, 0.69±0.12, 0.72±0.15 and 0.82±0.15 in CG cancer, all the parameter were significantly lower in CG cancer than SH(fig 1, table1 ). The 10th ADC yielded areas under the ROC curve (AUCs) of 0.91 for the differentiation of carcinoma and SH, which was higher than mean ADC(0.84), and the ROC of the 25th(0.86) and 50th(0.85) showed no difference from ADC(fig 2).

### Conclusion and discussion

The low ADC value in cancer was mainly due to the increased cells and the destruction of acinar, thus a more dense structure, and less free fluid. There is an increase in the stromal component and reduce in the acinar component in SH, which also limit the diffusion of water. The 10% ADC may mainly reflect the diffusion of stromal tissue in SH, and densely packed malignant cells in cancer, which avoid some confusion improve the distinguishing of the SH and cancer. In summary, histogram analysis of apparent diffusion coefficient could potentially improve the differentiation of prostate cancer in CG.

### Acknowledgements

No acknowledgement found.

### References

[1] Donati O F, Mazaheri Y, Afaq A, et al. Prostate cancer aggressiveness: assessment with whole-lesion histogram analysis of the apparent diffusion coefficient[J]. Radiology,2014,271(1):143-152.

[2] Lin Y, Li H, Chen Z, et al. Correlation of histogram analysis of apparent diffusion coefficient with uterine cervical pathologic finding. AJR Am J Roentgenol 2015;204(5):1125-1131.

### Figures

A an SH nodule in the right CG with hyperintensy on T2WI image. B the nodule showed a slightly high signal in DWI image. C.the nodule revealed a low ADC value in ADC map. D a cancer lesion in the CG with hyperintensy on T2WI image. E the lesion showed a slightly high signal in DWI image. F.the lesion reveal a remarkbly lower ADC value than SH in ADC map.

Table1.The histogram analysis of the ADC value for CG cancer and SH

The ROC of the ADC parameters, and the 10th ADC revealed the highest AUC value.

Proc. Intl. Soc. Mag. Reson. Med. 24 (2016)
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