# Usefulness of apparent diffusion coefficient values and magnetic resonance imaging histogram analysis for identifying histological types of preoperative testicular tumors

## TL;DR

This study shows that MRI and apparent diffusion coefficient values can help distinguish between types of testicular tumors before surgery.

## Contribution

The study introduces histogram analysis of MRI data to differentiate histological types of testicular tumors preoperatively.

## Key findings

- Seminomas had higher ADC ratios than malignant lymphomas and non-seminomas.
- Malignant lymphomas showed higher kurtosis and skewness values compared to seminomas and non-seminomas.
- MRI histogram analysis proved effective in distinguishing testicular tumor subtypes.

## Abstract

Only a few studies have performed histogram analysis for the differential diagnosis of testicular tumors. Therefore, the aim of this study was to evaluate the ability of magnetic resonance imaging, including diffusion-weighted imaging with apparent diffusion coefficient values, to differentiate between the histological types of testicular tumors.

Of the 156 testicular tumors diagnosed at our hospital between January 2010 and July 2023, 65 cases diagnosed with magnetic resonance imaging were included. Tumors were categorized as seminoma, non-seminoma, and malignant lymphoma. Apparent diffusion coefficient values were calculated and analyzed using the ratio to non-tumor testes and histograms according to tumor subtypes.

Among the 65 cases, 46, 14, and 5 entailed seminomas, non-seminomas, and malignant lymphomas, respectively. The apparent diffusion coefficient value ratio of seminomas (0.745 ± 0.132) was significantly higher than that of malignant lymphomas (0.531 ± 0.119, p = 0.013), and the apparent diffusion coefficient value ratios of non-seminomas (1.197 ± 0.430) were significantly higher than those of seminomas and malignant lymphomas (p = 0.0013 and p < 0.001, respectively). Seminomas and malignant lymphomas had significantly higher kurtosis values (8.55 ± 5.76 and 18.11 ± 5.22, respectively) than non-seminomas (4.92 ± 3.85, p = 0.012 and p = 0.0022, respectively). Malignant lymphomas had significantly higher kurtosis values than seminomas (p = 0.0123). Seminomas and malignant lymphomas had significantly higher skewness values (1.77 ± 1.00 and 3.12 ± 0.28, respectively) than non-seminomas (0.52 ± 1.17, p = 0.0016 and p < 0.001, respectively). Malignant lymphomas had higher skewness than seminomas (p < 0.001).

The present results demonstrate the efficacy of magnetic resonance imaging with apparent diffusion coefficient values and histograms in the differentiation of testicular tumor subtypes. A pre-operative diagnosis of testicular tumor subtypes may enable more effective management of testicular tumors, including pre-operative counseling and early treatment planning.