Assessment of Response to Neoadjuvant Chemoradiotherapy by 18F-FDG PET/CT in Patients With Locally Advanced Esophagogastric Junction Adenocarcinoma

• Published in: Clinical nuclear medicine Vol. 45; no. 1; pp. 38 - 43
• Main Authors: Sánchez-Izquierdo, Nuria, Perlaza, Pilar, Pagès, Mario, Buxó, Elvira, Rios, José, Rubello, Domenico, Colletti, Patrick M., Mayoral, Maria, Casanueva, Sebastian, Fernández-Esparrach, Gloria, Ginés, Angels, Fuster, David
• Format: Journal Article
• Language: English
• Published: United States Lippincott Williams & Wilkins 01-01-2020; Copyright Wolters Kluwer Health, Inc. All rights reserved
• Subjects: Adenocarcinoma - diagnostic imaging; Adenocarcinoma - pathology; Adenocarcinoma - therapy; Chemoradiotherapy; Esophageal Neoplasms - diagnostic imaging; Esophageal Neoplasms - pathology; Esophageal Neoplasms - therapy; Esophagogastric Junction - diagnostic imaging; Esophagogastric Junction - drug effects; Esophagogastric Junction - pathology; Esophagogastric Junction - radiation effects; Female; Fluorodeoxyglucose F18; Humans; Male; Middle Aged; Neoadjuvant Therapy; Positron Emission Tomography Computed Tomography; Prognosis; Prospective Studies
• ISSN: 0363-9762; 1536-0229
• DOI: 10.1097/RLU.0000000000002840

PURPOSEThe outcome of locally advanced adenocarcinoma of the esophagogastric junction (AEG) treated with preoperative chemoradiotherapy is heterogeneous, and favorable response to this treatment is a key factor in the patientʼs prognosis. The aim of this study was to evaluate F-FDG PET/CT in assessing metabolic response in patients with AEG.
MATERIALS AND METHODSThis prospective study evaluated all consecutive patients with potentially operable locally advanced AEG who were candidates for neoadjuvant chemoradiotherapy. PET/CT and contrast-enhanced thoracoabdominal CT were performed at baseline and 2 weeks after completion of chemoradiotherapy for response evaluation. The response rate was assessed using Response Evaluation Criteria in Solid Tumors criteria for contrast-enhanced thoracoabdominal CT and Positron Emission Tomography Response Criteria in Solid Tumors criteria for PET/CT. The regression rate was assessed using a 5-grade histopathology scoring system of the surgically resected tumor. Metastatic lesions were confirmed by histopathology examination or imaging and clinical follow-up at 6 months.
RESULTSA total of 40 cases were finally included in the study. Distant metastases were found in the baseline PET/CT in 6 of 40 cases (retroperitoneal [2] or mediastinal/hiliar [1] lymph nodes and liver [2] or bone [1] metastases) and were therefore excluded from surgery. Pathologic response correlated with the ΛSUVmax threshold of ≤45% (P = 0.033). CT response correlated well with both the baseline SUVmax (P = 0.039) and the ΛSUVmax (P = 0.001). Five-year survival curves for AEG correlated with the ΛSUVmax using a threshold of ≤45% for both progression-free and overall survival.
CONCLUSIONSF-FDG PET/CT is useful for diagnosing nonsuspected metastasis before neoadjuvancy in potentially operable AEG. The ΛSUV correlates with pathologic response and is a long-term independent prognostic factor of survival.