Mechanical property characterization of prostate cancer using a minimally motorized indenter in an ex vivo indentation experiment.
OBJECTIVE
To measure the mechanical property of prostatic tissues using a minimally motorized indenter and to determine whether measurable differences in mechanical property exist between cancerous and noncancerous tissues in an ex vivo experiment.


METHODS
A total of 552 sites from 46 prostate specimens taken during radical prostatectomy underwent an indentation experiment with a minimally motorized indenter, and the elastic modulus (Young's modulus) of the tissue was estimated.


RESULTS
The mean elastic modulus of the regions containing cancer and noncancer was 24.1 ± 14.5 and 17.0 ± 9.0 kPa, respectively. In the noncancerous regions, the prostate was separated into 5 parts according to the post hoc test for comparing the elastic modulus between the 2 groups: part 1, lateral apex; part 2, medial apex; part 3, lateral-mid; part 4, lateral base; and part 5, medial-mid and medial base. In the regions containing cancer tissue, the prostate was also separated into 5 parts: part 1, lateral apex and medial apex; part 2, lateral-mid; part 3, lateral base; part 4, medial base; and part 5, medial-mid. The elastic modulus was greater in the tissue with a Gleason score of 8 than in the other tissue. The elastic modulus was significantly greater in the tissue with a tumor volume >5 cm(3) than in the other tissue.


CONCLUSIONS
We determined the elastic moduli of prostatic tissue as a quantitative and objective parameter according to the regions of the prostate, the presence of cancerous tissue, the tumor volume, and the Gleason score.
Ahn
Bum-Mo
BM
Department of Mechanical Engineering, Korea Advanced Institute of Science and Technology School of Mechanical, Aerospace and Systems Engineering, Daejeon, Korea.
Kim
Jung
J
Ian
Lorenzo
L
Rha
Kun-Ho
KH
Kim
Hyung-Joo
HJ
D000230:Adenocarcinoma / Q000473:pathology* / Q000601:surgery; D000328:Adult; D000368:Aged; D055119:Elastic Modulus; D004867:Equipment Design; D006801:Humans; D008297:Male; D008875:Middle Aged; D009367:Neoplasm Staging; D011467:Prostate / Q000473:pathology*; D011468:Prostatectomy; D011471:Prostatic Neoplasms / Q000473:pathology* / Q000601:surgery; D014160:Transducers, Pressure