Development of a New Magnetometer for Sentinel Lymph Node Mapping Designed for Video-Assisted Thoracic Surgery in Non-Small Cell Lung Cancer.
BACKGROUND
We previously developed a method for sentinel lymph node (SLN) mapping in non-small cell lung cancer (NSCLC), based on the magnetic force produced by a magnetite tracer already approved for use as a contrast material for magnetic resonance imaging. However, it is difficult to use that technique with video-assisted thoracic surgery (VATS) because the sensing element of the magnetometer is large and thick. The purpose of the present study was to develop a smaller, thinner VATS-compatible magnetometer.


METHODS
The tracer employed was Ferucarbotran, a colloidal solution of superparamagnetic iron oxide coated with carbodextran. Fifteen patients with clinical stage I NSCLC were enrolled, and each received 1.6 mL of Ferucarbotran, injected intraoperatively at 5 points around the tumor. The magnetic force within the sampling lymph nodes was measured using the new VATS-compatible magnetometer.


RESULTS
SLNs were detected in 11 (73.3%) of the 15 patients using the VATS-compatible magnetometer. The average number of SLNs identified per patient was 1.8 (range 0-4). No complications related to the SLN detection method were observed.


CONCLUSIONS
The new VATS-compatible magnetometer appears to have substantial advantages over techniques using a radioisotope and our earlier magnetometer, as it can be inserted through the small VATS port site.
Akita University Graduate School of Medicine, Akita, Japan i-karo@mui.biglobe.ne.jp.
Kazuhiro
K
Imai
Akita University Graduate School of Medicine, Akita, Japan.
Yasushi
Y
Kawaharada
Akita University Graduate School of Medicine, Akita, Japan.
Jun-Ichi
J
Ogawa
Akita University Graduate School of Medicine, Akita, Japan.
Hajime
H
Saito
Akita University Graduate School of Medicine, Akita, Japan.
Satoshi
S
Kudo
Akita University Graduate School of Medicine, Akita, Japan.
Shinogu
S
Takashima
Akita University Graduate School of Medicine, Akita, Japan.
Yoshitaro
Y
Saito
Akita University Graduate School of Medicine, Akita, Japan.
Maiko
M
Atari
Akita University Graduate School of Medicine, Akita, Japan.
Aki
A
Ito
Akita University Graduate School of Medicine, Akita, Japan.
Kaori
K
Terata
Akita University Graduate School of Medicine, Akita, Japan.
Kei
K
Yoshino
Akita University Graduate School of Medicine, Akita, Japan.
Yusuke
Y
Sato
Akita University Graduate School of Medicine, Akita, Japan.
Satoru
S
Motoyama
Akita University Graduate School of Medicine, Akita, Japan.
Yoshihiro
Y
Minamiya
D000368:Aged; D002289:Carcinoma, Non-Small-Cell Lung / Q000601:surgery*; D004867:Equipment Design; D052203:Ferrosoferric Oxide / Q000627:therapeutic use; D006801:Humans; D008175:Lung Neoplasms / Q000601:surgery*; D060306:Magnetometry / Q000295:instrumentation*; D008875:Middle Aged; D021701:Sentinel Lymph Node Biopsy / Q000295:instrumentation* / Q000379:methods*; D020775:Thoracic Surgery, Video-Assisted / Q000295:instrumentation*
D052203:Ferrosoferric Oxide
lung cancer; magnetometer; sentinel lymph node; video-assisted thoracic surgery