Table 1 Periprostatic fat measurement techniques on imaging and their outcomes in previous studies.

Woo et al.¹⁵ Korea N = 190

Radical prostatectomy

Surgery

Periprostatic and subcutaneous fat thicknesses.

Preoperative mid-sagittal T₂W MRI. Measured the shortest perpendicular distance from symphysis pubis to skin and prostate.

Positive correlation between the periprostatic fat thickness and GS^*

Roermund et al.⁷ Netherlands N = 902

Prostate biopsies (? number)

Brachytherapy

Periprostatic fat area (cm²)/subcutaneous fat thickness (cm).

Two transverse 3 mm-thick CT slices at different levels. Pelvic fat was defined by the density range −190 to −30 HU^*. Fat density (%) was calculated by dividing periprostatic fat area by total contour area.

Periprostatic fat area and density were not correlated with Prostate cancer aggressiveness

Roermund et al. (2010) Netherlands N = 932

Prostate biopsies (? number)

External radiotherapy and brachytherapy

Periprostatic fat area (cm²)/Subcutaneous fat thickness.

Single transverse CT slice at the level of the femoral head and greater trochanter. Defined the pelvic fat by the density range −190 to −30 HU^*. Fat density (%) was calculated by dividing periprostatic fat area by total contour area.

Higher periprostatic fat density had more often aggressive prostate cancer.

Bhindi et al.²⁵ Canada N = 931

10–12 prostate biopsies

unknown

Periprostatic fat thickness.

Trans rectal ultrasonography (TRUS). The periprostatic fat was measured from the shortest perpendicular distance between pubic bone and prostate.

Periprostatic fat can be used as predictor for prostate cancer and high-grade prostate cancer at biopsy.

Tan et al.¹⁷ USA N = 295

12 core prostate biopsies

unknown

Periprostatic fat volume and prostate volume

3T MRIs. Periprostatic fat was marked from the level of its base to apex on T₂W MR images ‘’cranial to caudal”. Ratio was calculated (fat volume/prostate volume)

Higher ratio may be a risk factor, is significantly associated with higher Gleason score

Zhang et al.¹⁶ China N = 184

Radical prostatectomy

Surgery

Periprostatic fat area (cm²) and Subcutaneous fat thickness

T₂W transverse MRI slice at the level of the femoral head and greater trochanter of the femur.

Periprostatic fat can predict the prognosis of patient with radical retropubic prostatectomy.