title: Comparison of Single-Photon Emission Computed Tomography-Computed Tomography (SPECT/CT) and Conventional Planar Lymphoscintigraphy for Sentinel Node Localization in Patients with Cutaneous Malignancies.
abstract: BACKGROUND
  Accurate preoperative lymphoscintigraphy is vital to performing sentinel lymph node biopsy (SLNB) for cutaneous malignancies. Potential advantages of single-photon emission computed tomography with integrated computed tomography (SPECT/CT) include the ability to readily identify aberrant drainage patterns as well as provide the surgeon with three-dimensional anatomic landmarks not seen on conventional planar lymphoscintigraphy (PLS).
  
  
  METHODS
  Patients with cutaneous malignancies who underwent SLNB with preoperative imaging using both SPECT/CT and PLS from 2011 to 2014 were identified.
  
  
  RESULTS
  Both SPECT/CT and PLS were obtained in 351 patients (median age, 69 years; range, 5-94 years) with cutaneous malignancies (melanoma = 300, Merkel cell carcinoma = 33, squamous cell carcinoma = 8, other = 10) after intradermal injection of99mtechnetium sulfur colloid (median dose 300 µCi). A mean of 4.3 hot spots were identified on SPECT/CT compared to 3.0 on PLS (p < 0.001). One hundred fifty-three patients (43.6 %) had identical findings between SPECT/CT and PLS, while 172 (49 %) had additional hot spots identified on SPECT/CT compared to only 24 (6.8 %) additional on PLS. SPECT/CT demonstrated additional nodal basins in 103 patients (29.4 %), compared to only 11 patients (3.1 %) with additional basins on PLS.
  
  
  CONCLUSIONS
  SPECT/CT is a useful adjunct that can help with sentinel node localization in challenging cases. It identified additional hot spots not seen on PLS in almost 50 % of patients. Because PLS identified hot spots not seen on SPECT/CT in 6.8 % of patients, we recommend using both modalities jointly. Long-term follow-up will be required to validate the clinical significance of the additional hot spots identified by SPECT/CT.
authors.affiliation: Department of Cutaneous Oncology, Moffitt Cancer Center, Tampa, FL, USA.
authors.forename: Matthew P
authors.initials: MP
authors.lastname: Doepker
authors.affiliation: Department of Surgery, University of California Irvine Medical Center, Orange, CA, USA.
authors.forename: Maki
authors.initials: M
authors.lastname: Yamamoto
authors.affiliation: Department of Cutaneous Oncology, Moffitt Cancer Center, Tampa, FL, USA.
authors.forename: Matthew A
authors.initials: MA
authors.lastname: Applebaum
authors.affiliation: Department of Cutaneous Oncology, Moffitt Cancer Center, Tampa, FL, USA.
authors.forename: Nupur U
authors.initials: NU
authors.lastname: Patel
authors.affiliation: Department of Radiology, Moffitt Cancer Center, Tampa, FL, USA.
authors.forename: M
authors.initials: M
authors.lastname: Jaime Montilla-Soler
authors.affiliation: Department of Cutaneous Oncology, Moffitt Cancer Center, Tampa, FL, USA.
authors.forename: Amod A
authors.initials: AA
authors.lastname: Sarnaik
authors.affiliation: Department of Cutaneous Oncology, Moffitt Cancer Center, Tampa, FL, USA.
authors.forename: C
authors.initials: C
authors.lastname: Wayne Cruse
authors.affiliation: Department of Cutaneous Oncology, Moffitt Cancer Center, Tampa, FL, USA.
authors.forename: Vernon K
authors.initials: VK
authors.lastname: Sondak
authors.affiliation: Department of Cutaneous Oncology, Moffitt Cancer Center, Tampa, FL, USA. Jonathan.zager@moffitt.org.
authors.forename: Jonathan S
authors.initials: JS
authors.lastname: Zager
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D015266:Carcinoma, Merkel Cell / Q000000981:diagnostic imaging / Q000473:pathology / Q000601:surgery; D002294:Carcinoma, Squamous Cell / Q000000981:diagnostic imaging / Q000473:pathology / Q000601:surgery; D002648:Child; D002675:Child, Preschool; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008197:Lymph Node Excision; D061305:Lymphoscintigraphy / Q000379:methods*; D008297:Male; D008545:Melanoma / Q000000981:diagnostic imaging / Q000473:pathology / Q000601:surgery; D008875:Middle Aged; D011379:Prognosis; D019275:Radiopharmaceuticals; D012189:Retrospective Studies; D012509:Sarcoma / Q000000981:diagnostic imaging / Q000473:pathology / Q000601:surgery; D000071036:Sentinel Lymph Node / Q000000981:diagnostic imaging* / Q000473:pathology / Q000601:surgery; D021701:Sentinel Lymph Node Biopsy; D012878:Skin Neoplasms / Q000000981:diagnostic imaging* / Q000473:pathology / Q000601:surgery; D015899:Tomography, Emission-Computed, Single-Photon / Q000379:methods*; D014057:Tomography, X-Ray Computed / Q000379:methods*; D055815:Young Adult
chemical_list: D019275:Radiopharmaceuticals