Computed tomography (CT) perfusion as an early predictive marker for treatment response to neoadjuvant chemotherapy in gastroesophageal junction cancer and gastric cancer--a prospective study.
OBJECTIVE
To evaluate whether early reductions in CT perfusion parameters predict response to pre-operative chemotherapy prior to surgery for gastroesophageal junction (GEJ) and gastric cancer.


METHODS
Twenty-eight patients with adenocarcinoma of the gastro-esophageal junction (GEJ) and stomach were included. Patients received three series of chemotherapy before surgery, each consisting of a 3-week cycle of intravenous epirubicin, cisplatin or oxaliplatin, concomitant with capecitabine peroral. The patients were evaluated with a CT perfusion scan prior to, after the first series of, and after three series of chemotherapy. The CT perfusion scans were performed using a 320-detector row scanner. Tumour volume and perfusion parameters (arterial flow, blood volume and permeability) were computed on a dedicated workstation with a consensus between two radiologists. Response to chemotherapy was evaluated by two measures. Clinical response was defined as a tumour size reduction of more than 50%. Histological response was evaluated based on residual tumour cells in the surgical specimen using the standardized Mandard Score 1 to 5, in which values of 1 and 2 were classified as responders, and 3 to 5 were classified as nonresponders.


RESULTS
A decrease in tumour permeability after one series of chemotherapy was positively correlated with clinical response after three series of chemotherapy. Significant changes in permeability and tumour volume were apparent after three series of chemotherapy in both clinical and histological responders. A cut-off value of more than 25% reduction in tumour permeability yielded a sensitivity of 69% and a specificity of 58% for predicting clinical response.


CONCLUSIONS
Early decrease in permeability is correlated with the likelihood of clinical response to pre-operative chemotherapy in GEJ and gastric cancer. As a single diagnostic test, CT Perfusion only has moderate sensitivity and specificity in response assessment of pre-operative chemotherapy making it insufficient for clinical decision purposes.
Department of Radiology, Rigshospitalet, Copenhagen, Denmark.
Martin
M
Lundsgaard Hansen
Department of Radiology, Rigshospitalet, Copenhagen, Denmark.
Eva
E
Fallentin
Department of Radiology, Rigshospitalet, Copenhagen, Denmark; Bachelor's Degree Programme in Radiography, Department of Technology, Metropolitan University College, Copenhagen, Denmark.
Carsten
C
Lauridsen
Department of Clinical Physiology, Nuclear Medicine and PET, Rigshospitalet, Copenhagen, Denmark.
Ian
I
Law
Department of Pathology, Rigshospitalet, Copenhagen, Denmark.
Birgitte
B
Federspiel
Department of Oncology, Rigshospitalet, Copenhagen, Denmark.
Lene
L
Bæksgaard
Department of Surgical Gastroenterology, Rigshospitalet, Copenhagen, Denmark.
Lars Bo
LB
Svendsen
Department of Radiology, Rigshospitalet, Copenhagen, Denmark.
Michael Bachmann
MB
Nielsen
D000230:Adenocarcinoma / Q000000981:diagnostic imaging* / Q000628:therapy*; D000328:Adult; D000368:Aged; D014408:Biomarkers, Tumor; D004943:Esophagogastric Junction / Q000000981:diagnostic imaging*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D020360:Neoadjuvant Therapy; D011446:Prospective Studies; D013274:Stomach Neoplasms / Q000000981:diagnostic imaging* / Q000628:therapy*; D014057:Tomography, X-Ray Computed
D014408:Biomarkers, Tumor