Comparison of 3D printed prostate models with standard radiological information to aid understanding of the precise location of prostate cancer: A construct validation study

Abstract

Background: To investigate the reliability with which healthcare professionals with different levels of expertise are able to impart the exact location of prostate cancer (PCA) after (A) reading written magnetic resonance imaging (MRI) reports, (B) attending MRI presentations in multidisciplinary team meetings (MDT), and (C) examining 3D printed prostate models, which represents a new technology to describe the location of PCA lesions.

Methods: We used three different PCA cases to assess the three information tools. Construct validation was performed using two healthcare groups with different levels of expertise: (1) Nine expert urologists in PCA, and (2) nine medical students. After each information tool, the study participants plotted the tumor location in a 2-dimensional prostate diagram. A scoring system was established to evaluate the drawings in terms of accuracy of plotting tumor position. Data are shown as median scores with interquartile range.

Results: Within the expert group, no significant difference was seen in the overall scoring results between the information tools (p = 0.34). Medical students performed significantly worse with MDT information (p = 0.03). Experts performed better in all three information tools compared to students, resulting in a significantly 25% higher overall total score (25.0[22.3-26.7] vs. 20.0[15.0-24.0], p<0.001). The difference was largest after MDT information, with experts showing a 49% better scoring (p<0.001), and second largest with the 3D printed models, showing a 17% better scoring of the experts (p = 0.07). No difference was found in the written MRI report scoring results between experts and students.

Conclusions: 3D printed models provided better orientation guide to medical students compared to MDT MRI presentations. This indicates that the 3D printed models might be easier to understand than the current gold standard MDT conferences. Therefore, 3D models may play an increasingly important role in providing guidance for orientation for less experienced individuals, such as surgical trainees.

Fig 1. Swedish national prostate biopsy and MRI report template.

1) Side (sagittal) view of the prostate, 2) ventral (coronal) view of the prostate, 3) transverse (axial) sections A-C of pictures 1) and 2). The study participants used this diagram without the colour lines to plot the prostate tumor location. The correctly plotted tumor location of case 3 is shown in the diagram (pink areas). For the scoring system picture 1) was divided in an anterior and posterior half (green line), picture 2) in a right and left half (red line) and picture 3 A-C in quadrants (blue, orange, yellow, turquoise). (MRI) magnetic resonance imaging; (SV) seminal vesicle; (a) anterior; (p) posterior; broken lines in picture 1) mark the urethra.

Fig 2. 3D printed prostate models (case 1–3) used in the study.

The models were manufactured by 3D Systems, Inc. 5381 South Alkire Circle, Littleton, Colorado 80127 USA. Each prostate model contained a single prostate cancer lesion (pink colour). Tumor characteristics for case 1 were cT2, PI-RADS 5 (size 15x9x21 mm), mriT3, pT3a, Gleason 4+3 (tertiary grade 5); for case 2 cT2-3, PI-RADS 5 (size 19x12x17 mm), mriT3, pT2c, Gleason 4+3; and for case 3 T1c, PI-RADS 5 (size 27x11x21 mm), mriT3, pT2c, Gleason 3+3 (tertiary grade 4).

Fig 3. Prostate cancer lesion of case 3 according to 3D printed prostate model, MRI and prostate template.

In (1) corresponding side (sagittal) views and (2) according to ventral (coronal) views in 3D printed prostate model and prostate template and different sequences of the corresponding axial view in MRI (corresponds to broken line in section B). (SV) seminal vesicle, (a) anterior, (p) posterior. Arrows indicate prostate cancer in MRI.