title: SPECT/CT for SLN dissection in vulvar cancer: Improved SLN detection and dissection by preoperative three-dimensional anatomical localisation.
abstract: OBJECTIVE
  In this study, we assessed the feasibility and clinical advantages of single photon emission computed tomography with CT (SPECT/CT) for sentinel lymph node (SLN) detection in vulvar cancer.
  
  
  METHODS
  This is a unicentric prospective trial. Vulvar cancer patients underwent preoperative SLN marking (10MBq Technetium (TC)-99m-nanocolloid) and subsequent planar lymphoscintigraphy (LSG) and SPECT/CT for SLN visualization. Directly before surgery, a patent blue dye was injected. We assessed detection rates of SPECT/CT and those of planar LSG and intraoperative detection. We analyzed the sensitivity, negative predictive value and false negative rate.
  
  
  RESULTS
  At Hannover Medical School, 40 vulvar cancer patients underwent SLN dissection after preoperative LSG and SPECT/CT. The mean diameter of all tumors in final histology was 2.23 (0.1-10.5) cm with a mean tissue infiltration of 3.93 (0.25-11) mm. In preoperative imaging, SPECT/CT identified significantly more SLNs (mean 8.7 (1-35) LNs per patient) compared to LSG (mean 5.9 (0-22) LNs, p<0.01). In addition, SPECT/CT led to a high spatial resolution and anatomical localization of SLNs. Thus, SPECT/CT identified aberrant lymphatic drainage in 7/40 (17.5%) patients. There were no significant differences, but significant correlation was found between SPECT/CT and intraoperative SLN identification. Regarding inguino-femoral LNs, for all patients who underwent complete groin dissection, sensitivity was 100%, NPV was 100% and false negative rate was 0%.
  
  
  CONCLUSIONS
  SPECT/CT leads to higher SLN identification compared to LSG in vulvar cancer. Due to its higher spatial resolution and three-dimensional anatomical localisation of SLNs, SPECT/CT provides the surgeon with important additional information, facilitates intraoperative SLN detection and predicts aberrant lymphatic drainage.
authors.affiliation: Department of Obstetrics and Gynaecology, Hannover Medical School, Germany.
authors.forename: R
authors.initials: R
authors.lastname: Klapdor
authors.affiliation: Institute of Pathology, Hannover Medical School, Germany.
authors.forename: F
authors.initials: F
authors.lastname: Länger
authors.affiliation: Department of Nuclear Medicine, Hannover Medical School, Germany.
authors.forename: K F
authors.initials: KF
authors.lastname: Gratz
authors.affiliation: Department of Obstetrics and Gynaecology, Hannover Medical School, Germany.
authors.forename: P
authors.initials: P
authors.lastname: Hillemanns
authors.affiliation: Department of Obstetrics and Gynaecology, Hannover Medical School, Germany. Electronic address: hertel.hermann@mh-hannover.de.
authors.forename: H
authors.initials: H
authors.lastname: Hertel
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D005260:Female; D006801:Humans; D008198:Lymph Nodes / Q000000981:diagnostic imaging / Q000473:pathology* / Q000601:surgery*; D008207:Lymphatic Metastasis; D008875:Middle Aged; D064847:Multimodal Imaging / Q000379:methods; D057234:Preoperative Period; D011446:Prospective Studies; D021701:Sentinel Lymph Node Biopsy / Q000379:methods*; D013668:Technetium Tc 99m Aggregated Albumin; D015899:Tomography, Emission-Computed, Single-Photon / Q000379:methods; D014057:Tomography, X-Ray Computed / Q000379:methods; D014846:Vulvar Neoplasms / Q000000981:diagnostic imaging / Q000473:pathology* / Q000601:surgery*
chemical_list: D013668:Technetium Tc 99m Aggregated Albumin; C083602:technetium Tc 99m nanocolloid
keywords: Lymphoscintigraphy; SPECT/CT; Sentinel lymph node concept; Vulvar carcinoma