Pelvic Lymph Node Topography for Radiotherapy Treatment Planning From Ferumoxtran-10 Contrast-Enhanced Magnetic Resonance Imaging

• Published in: International journal of radiation oncology, biology, physics Vol. 74; no. 3; pp. 844 - 851
• Main Authors: Dinniwell, Robert, M.D, Chan, Philip, M.B.B.S, Czarnota, Gregory, Ph.D, M.D, Haider, Masoom A., M.D, Jhaveri, Kartik, M.D, Jewett, Michael, M.D, Fyles, Anthony, M.D, Jaffray, David, Ph.D, Milosevic, Michael, M.D
• Format: Journal Article
• Language: English
• Published: United States Elsevier Inc 01.07.2009
• Subjects: Aged; Aged, 80 and over; Aorta, Abdominal - anatomy & histology; ARTERIES; BLADDER; Cancer; CONTRAST MEDIA; Dextrans; Endometrial Neoplasms - pathology; Endometrial Neoplasms - radiotherapy; Female; Ferrosoferric Oxide; Ferumoxtran-10; Hematology, Oncology and Palliative Medicine; Humans; Iliac Artery - anatomy & histology; Iliac Vein - anatomy & histology; Iron; IRON OXIDES; Lymph node; LYMPH NODES; Lymph Nodes - pathology; Lymphatic Metastasis - pathology; MAGNETIC RESONANCE; Magnetic resonance (MR); Magnetic Resonance Imaging - methods; Magnetite Nanoparticles; Male; Medical Illustration; METASTASES; Middle Aged; NEOPLASMS; NMR IMAGING; Oxides; PATIENTS; Pelvic Neoplasms - pathology; Pelvis; PROSTATE; Prostatic Neoplasms - pathology; Prostatic Neoplasms - radiotherapy; Radiology; RADIOLOGY AND NUCLEAR MEDICINE; RADIOTHERAPY; Ultrasmall superparamagnetic iron oxide (USPIO); Urinary Bladder Neoplasms - pathology; Urinary Bladder Neoplasms - radiotherapy; Uterine Cervical Neoplasms - pathology; Uterine Cervical Neoplasms - radiotherapy; Magnetic resonance (MR); Lymph node; Radiotherapy; Ferumoxtran-10; Cancer; Ultrasmall superparamagnetic iron oxide (USPIO)
• ISSN: 0360-3016; 1879-355X
• DOI: 10.1016/j.ijrobp.2008.09.026

Purpose To define a population-based pelvic lymph node clinical target volume (CTV) for radiotherapy treatment planning using magnetic resonance (MR) imaging and the ultrasmall superparamagnetic iron oxide lymph node contrast agent ferumoxtran-10. Methods and Materials A total of 55 eligible patients with endometrial, cervical, prostate, or bladder cancer underwent MR imaging sessions before and after contrast administration on 2 consecutive days. Ferumoxtran-10 was administered immediately after the first scan. The three-dimensional spatial distribution of the pelvic lymph nodes was determined in relation to adjacent vessels and other musculoskeletal landmarks, from which guidelines for determining a nodal CTV in individual patients were developed. Results On average, 30 lymph nodes (range, five to 62 nodes) were identified in each patient. The distribution of nodal distances to the closest artery or vein was observed to vary in different anatomic regions. Symmetrical three-dimensional margins of expansion around the distal para-aortic (12 mm), common iliac (10 mm), external iliac (9 mm), and internal iliac (10 mm) vessels, drawn in continuity with a 12-mm expansion anterior to the sacrum and a 22-mm expansion medial to the pelvic sidewall, were shown to encompass the majority of detectable lymph nodes in most patients. Conclusion Use of MR lymphography with ferumoxtran-10 provides an objective description of lymph node locations for radiotherapy planning. Use of this nodal CTV model in clinical practice could ensure a high probability of encompassing the regions at risk of harboring metastatic disease while minimizing the dose to adjacent normal tissues.