Interobserver reproducibility of diffusion-weighted MRI in monitoring tumor response to neoadjuvant therapy in esophageal cancer.
OBJECTIVE
To investigate the reproducibility of diffusion-weighted magnetic resonance imaging (DW-MRI) in assessing tumor response early in the course of neoadjuvant chemoradiotherapy in patients with operable esophageal cancer.


METHODS
Eleven male patients (mean age 54.8 years) with newly diagnosed esophageal cancer underwent DW-MRI before and 10 days after start of chemoradiotherapy. Reproducibility of apparent diffusion coefficient (ADC) measurements by manual (freehand) and semi-automated volumetric methods was assessed.


RESULTS
Interobserver reproducibility for the assessment of mean tumor ADC by the manual measurement method was good, with an ICC of 0.69 (95% CI, 0.36 to 0.85; P = 0.001). Interobserver reproducibility for the assessment of mean tumor ADC by the semi-automated volumetric measurement method was very good, with an ICC of 0.96 (95% CI, 0.91 to 0.98; P<0.001).


CONCLUSIONS
Semi-automated volumetric ADC measurements have higher reproducibility than manual ADC measurements in assessing tumor response to chemoradiotherapy in patients with esophageal adenocarcinoma.
Department of Radiology, Atrium Medical Center Parkstad, Heerlen, The Netherlands; Department of Radiology, Maastricht University Medical Center, Maastricht, The Netherlands.
Robert M
RM
Kwee
Department of Radiology, Atrium Medical Center Parkstad, Heerlen, The Netherlands.
Alexander K
AK
Dik
Department of Surgery, Atrium Medical Center Parkstad, Heerlen, The Netherlands; Surgical Collaborative Network Limburg, Limburg, The Netherlands.
Meindert N
MN
Sosef
Department of Medical Physics, Atrium Medical Center Parkstad, Heerlen, The Netherlands.
Ralph C M
RC
Berendsen
Department of Radiology, Atrium Medical Center Parkstad, Heerlen, The Netherlands.
Sander
S
Sassen
Department of Radiation Oncology, MediClin Robert-Janker-Clinic, Bonn, Germany.
Guido
G
Lammering
Department of Pathology, Atrium Medical Center Parkstad, Heerlen, The Netherlands.
Ruud
R
Clarijs
Department of Internal Medicine and Gastroenterology, Atrium Medical Center Parkstad, Heerlen, The Netherlands.
Liekele E
LE
Oostenbrug
Department of Surgery, Academic Medical Center, Amsterdam, The Netherlands.
Rachel L G M
RL
Blom
Department of Radiology, Atrium Medical Center Parkstad, Heerlen, The Netherlands.
Roy F A
RF
Vliegen
D000230:Adenocarcinoma / Q000175:diagnosis* / Q000453:epidemiology / Q000628:therapy*; D000328:Adult; D000368:Aged; D059248:Chemoradiotherapy; D038524:Diffusion Magnetic Resonance Imaging; D004938:Esophageal Neoplasms / Q000175:diagnosis* / Q000453:epidemiology / Q000628:therapy*; D006801:Humans; D008297:Male; D008875:Middle Aged; D008991:Monitoring, Physiologic / Q000379:methods* / Q000706:statistics & numerical data; D020360:Neoadjuvant Therapy; D015588:Observer Variation; D011379:Prognosis; D015203:Reproducibility of Results; D016896:Treatment Outcome