title: Tumor contact with prostate capsule on magnetic resonance imaging: A potential biomarker for staging and prognosis.
abstract: The high-spatial resolution of multiparametric magnetic resonance imaging (mpMRI) has improved the detection of clinically significant prostate cancer. mpMRI characteristics (extraprostatic extension [EPE], number of lesions, etc.) may predict final pathological findings (positive lymph node [pLN] and pathological ECE [pECE]) and biochemical recurrence (BCR). Tumor contact length (TCL) on MRI, defined as the length of a lesion in contact with the prostatic capsule, is a novel marker with promising early results. We aimed to evaluate TCL as a predictor of +pathological EPE (+pEPE),+pathological LN (+pLN), and BCR in patients undergoing robotic-assisted laparoscopic radical prostatectomy.
  
  
  
  A review was performed of a prospectively maintained single-institution database of men with prostate cancer who underwent prostate mpMRI followed by robotic-assisted laparoscopic radical prostatectomy without prior therapy from 2007 to 2015. TCL was measured using T2-weighted magnetic resonance images. Logistic and Cox regression analysis were used to assess associations of clinical, imaging, and histopathological variables with pEPE, pLN, and BCR. Receiver operating characteristic curves were used to characterize and compare TCL performance with Partin tables.
  
  
  
  There were 87/379 (23.0%)+pEPE, 18/384 (4.7%)+pLN, and 33/371 (8.9%) BCR patients. Patients with adverse pathology/oncologic outcomes had longer TCL compared to those without adverse outcomes (+pEPE: 19.8 vs. 10.1mm, P<0.0001,+pLN: 38.0 vs. 11.7mm, P<0.0001, and BCR: 19.2 vs. 11.2mm, P = 0.001). On multivariate analysis, TCL remained a predictor of+pEPE (odds ratio: 1.04, P = 0.001),+pLN (odds ratio: 1.07, P<0.0001), and BCR (hazard ratio: 1.03, P = 0.02). TCL thresholds for predicting+pEPE and+pLN were 12.5 and 19.7mm, respectively. TCL alone was found to have good predictive ability for+pEPE and+PLN (pEPE:TCLAUC: 0.71 vs. PartinAUC: 0.66, P = 0.21; pLN:TCLAUC: 0.77 vs. PartinAUC: 0.88, P = 0.04).
  
  
  
  We demonstrate that TCL is an independent predictor of+pEPE, +pLN, and BCR. If validated, this imaging biomarker may facilitate and inform patient counseling and decision-making.
authors: Urologic Oncology Branch, National Cancer Institute, National Institutes of Health, Bethesda, MD. Electronic address: speeditomike@gmail.com.
authors: Michael
authors: M
authors: Kongnyuy
authors: Urologic Oncology Branch, National Cancer Institute, National Institutes of Health, Bethesda, MD.
authors: Abhinav
authors: A
authors: Sidana
authors: Urologic Oncology Branch, National Cancer Institute, National Institutes of Health, Bethesda, MD.
authors: Arvin K
authors: AK
authors: George
authors: Urologic Oncology Branch, National Cancer Institute, National Institutes of Health, Bethesda, MD.
authors: Akhil
authors: A
authors: Muthigi
authors: Urologic Oncology Branch, National Cancer Institute, National Institutes of Health, Bethesda, MD.
authors: Amogh
authors: A
authors: Iyer
authors: Urologic Oncology Branch, National Cancer Institute, National Institutes of Health, Bethesda, MD.
authors: Richard
authors: R
authors: Ho
authors: Urologic Oncology Branch, National Cancer Institute, National Institutes of Health, Bethesda, MD.
authors: Raju
authors: R
authors: Chelluri
authors: Molecular Imaging Program, National Cancer Institute, National Institutes of Health, Bethesda, MD.
authors: Francesca
authors: F
authors: Mertan
authors: Urologic Oncology Branch, National Cancer Institute, National Institutes of Health, Bethesda, MD.
authors: Thomas P
authors: TP
authors: Frye
authors: Urologic Oncology Branch, National Cancer Institute, National Institutes of Health, Bethesda, MD.
authors: Daniel
authors: D
authors: Su
authors: Laboratory of Pathology, National Cancer Institute, National Institutes of Health, Bethesda, MD.
authors: Maria J
authors: MJ
authors: Merino
authors: Molecular Imaging Program, National Cancer Institute, National Institutes of Health, Bethesda, MD.
authors: Peter L
authors: PL
authors: Choyke
authors: Center for Interventional Oncology, National Cancer Institute & Clinical Center, National Institutes of Health, Bethesda, MD.
authors: Bradford J
authors: BJ
authors: Wood
authors: Urologic Oncology Branch, National Cancer Institute, National Institutes of Health, Bethesda, MD.
authors: Peter A
authors: PA
authors: Pinto
authors: Molecular Imaging Program, National Cancer Institute, National Institutes of Health, Bethesda, MD.
authors: Baris
authors: B
authors: Turkbey
mesh_terms: D000328:Adult; D000368:Aged; D019540:Area Under Curve; D014408:Biomarkers, Tumor; D002986:Clinical Trials as Topic; D006801:Humans; D008207:Lymphatic Metastasis; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D008875:Middle Aged; D009364:Neoplasm Recurrence, Local / Q000097:blood*; D009367:Neoplasm Staging; D049451:Nomograms; D011237:Predictive Value of Tests; D011379:Prognosis; D011467:Prostate / Q000000981:diagnostic imaging* / Q000473:pathology*; D017430:Prostate-Specific Antigen / Q000097:blood; D011468:Prostatectomy; D011471:Prostatic Neoplasms / Q000097:blood / Q000000981:diagnostic imaging* / Q000473:pathology*; D012372:ROC Curve; D012189:Retrospective Studies
chemical_list: D014408:Biomarkers, Tumor; D017430:Prostate-Specific Antigen
keywords: Biomarker; Capsule; Lymph node; Magnetic resonance imaging; Prostatic neoplasms