Investigating the role of SPECT/CT in dynamic sentinel lymph node biopsy for penile cancers

• Published in: European journal of nuclear medicine and molecular imaging 2017-07, Vol.44 (7), p.1176-1184
• Main Authors: Saad, Ziauddin Zia, Omorphos, Savvas, Michopoulou, Sofia, Gacinovic, Svetislav, Malone, Peter, Nigam, Raj, Muneer, Asif, Bomanji, Jamshed
• Format: Article
• Language: English
• Subjects: Adult; Aged; Aged, 80 and over; Biopsy; Cancer; Cardiology; Computed tomography; Contamination; Drainage basins; Genital cancers; Humans; Imaging; Localization; Lymph nodes; Lymphatic system; Male; Medicine; Medicine & Public Health; Middle Aged; Nuclear Medicine; Oncology; Original; Original Article; Orthopedics; Patients; Penile Neoplasms - diagnostic imaging; Penile Neoplasms - pathology; Penis; Radiology; Reclassification; Scintigraphy; Sentinel Lymph Node Biopsy; Single photon emission computed tomography; Single Photon Emission Computed Tomography Computed Tomography; Skin; Studies; Wound drainage
• ISSN: 1619-7070; 1619-7089
• DOI: 10.1007/s00259-017-3636-1

Purpose Currently, most centres use 2-D planar lymphoscintigraphy when performing dynamic sentinel lymph node biopsy in penile cancer patients with clinically impalpable inguinal nodes. This study aimed to investigate the role of SPECT/CT following 2-D planar lymphoscintigraphy (dynamic and static) in the detection and localization of sentinel lymph nodes in the groin. Methods A qualitative (visual) review was performed on planar followed by SPECT/CT lymphoscintigraphy in 115 consecutive patients (age 28–86 years) who underwent injection of 99m Tc-nanocolloid followed by immediate acquisition of dynamic (20 min) and early static scans (5 min) initially and further delayed static (5 min) images at 120 min followed by SPECT/CT imaging. The lymph nodes detected in each groin on planar lymphoscintigraphy and SPECT/CT were compared. Results A total of 440 and 467 nodes were identified on planar scintigraphy and SPECT/CT, respectively. Overall, SPECT/CT confirmed the findings of planar imaging in 28/115 cases (24%). In the remaining 87 cases (76%), gross discrepancies were observed between planar and SPECT/CT images. SPECT/CT identified 17 instances of skin contamination (16 patients, 13%) and 36 instances of in-transit lymphatic tract activity (24 patients, 20%) that had been interpreted as tracer-avid lymph nodes on planar imaging. In addition, SPECT/CT identified 53 tracer-avid nodes in 48 patients (42%) that were not visualized on planar imaging and led to reclassification of the drainage basins (pelvic/inguinal) of 27 tracer-avid nodes. Conclusions The addition of SPECT/CT improved the rate of detection of true tracer-avid lymph nodes and delineated their precise (3-D) anatomic localization in drainage basins.