Sentinel-node mapping in endometrial cancer patients: comparing SPECT/CT, gamma-probe and dye.
OBJECTIVE
The aim of this study was to compare preoperative SPECT/CT with gamma-probe and methylene blue-dye (MBD) in the identification of sentinel lymph node (SLN) in early stage endometrial cancer.


METHODS
40 stage-I EC patients (66.7 ± 9.7 years) underwent preoperative lymphoscintigraphy. After about 3 h from Tc-99m-albumin nanocolloid cervical injection, all patients underwent SPECT/CT study. MBD was injected into the cervix just before surgery under general anesthesia. All patients underwent SLN biopsy, hysterectomy, bilateral salpingo-oophorectomy, and radical regional lymphadenectomy. SPECT/CT findings were compared to those of gamma-probe and MBD techniques.


RESULTS
In 2 patients no nodal migration was observed, neither with MBD nor radiotracer. Detection rate of at least one SLN was 90% (36/40 patients) with SPECT/CT, 88% (35/40) intra-operatively with gamma-probe and 80% (32/40) with MBD. Only in 7/40 patients a bilateral migration was obtained with all considered modalities. In particular, bilateral detection was achieved in 26 patients with SPECT/CT, in 24 with gamma-probe and in 10 patients with MBD. The concordance site between SPECT/CT and intraoperative gamma-probe was 73% (29/40 patients: 2 without migration, 21 bilateral and 6 monolateral SLNs); while concordance site with MBD was found in 40% (16/40: 8 bilateral, 6 monolateral SLNs, 2 without SLNs). Overall, 628 LNs were dissected (mean 18 LNs per patient). The median number of SLNs removed was 2 (mean 2.5 per patient). Out of 91 SLNs: 43 were "hot and blue (HB)", 10 were blue only and 38 were hot only. LN metastases rate was 16%: 9/90 SLNs (7 HB, 2 hot only) were positive for metastases in 6 patients. Four non-SLNs were found positive in 3 patients, and all presented concomitant positive SLNs. False negative rate was 0%.


CONCLUSIONS
SPECT/CT had the highest detection rate and achieved the highest rate of bilateral mapping, compared to gamma-probe and MDB. SPECT/CT had moderate concordance with gamma-probe, and it can help the intraoperative detection of SLNs providing important information about their anatomic location.
Department of Nuclear Medicine, San Gerardo Hospital, ASST Monza, Via Pergolesi 33, 20900, Monza, Italy.
Federica
F
Elisei
Department of Nuclear Medicine, San Gerardo Hospital, ASST Monza, Via Pergolesi 33, 20900, Monza, Italy. cinzia.crivellaro@unimib.it.|School of Medicine and Surgery, University Milan-Bicocca, Milan, Italy. cinzia.crivellaro@unimib.it.
Cinzia
http://orcid.org/0000-0002-2645-5236
C
Crivellaro
Department of Obstetrics and Gynecology, ASST Monza, Monza, Italy.
Daniela
D
Giuliani
Tecnomed Foundation, University Milan-Bicocca, Milan, Italy.
Carlotta
C
Dolci
Department of Medical Physics, ASST Monza, Monza, Italy.
Elena
E
De Ponti
Department of Obstetrics and Gynecology, ASST Monza, Monza, Italy.
Luca
L
Montanelli
Department of Obstetrics and Gynecology, ASST Monza, Monza, Italy.
Maria
M
La Manna
Department of Nuclear Medicine, San Gerardo Hospital, ASST Monza, Via Pergolesi 33, 20900, Monza, Italy.
Luca
L
Guerra
Department of Nuclear Medicine, San Gerardo Hospital, ASST Monza, Via Pergolesi 33, 20900, Monza, Italy.
Maurizio
M
Arosio
Department of Nuclear Medicine, San Gerardo Hospital, ASST Monza, Via Pergolesi 33, 20900, Monza, Italy.|School of Medicine and Surgery, University Milan-Bicocca, Milan, Italy.
Claudio
C
Landoni
Department of Obstetrics and Gynecology, ASST Monza, Monza, Italy.
Alessandro
A
Buda
D000368:Aged; D000369:Aged, 80 and over; D004396:Coloring Agents / Q000378:metabolism*; D016889:Endometrial Neoplasms / Q000175:diagnosis / Q000000981:diagnostic imaging* / Q000378:metabolism / Q000473:pathology*; D005260:Female; D005720:Gamma Rays; D006801:Humans; D008751:Methylene Blue / Q000378:metabolism*; D008875:Middle Aged; D009367:Neoplasm Staging; D021701:Sentinel Lymph Node Biopsy / Q000379:methods*; D000072098:Single Photon Emission Computed Tomography Computed Tomography
D004396:Coloring Agents; D008751:Methylene Blue
Endometrial cancer; SPECT/CT; Sentinel lymph node