Multimodality Assessment of Esophageal Cancer: Preoperative Staging and Monitoring of Response to Therapy

Abstract

Esophageal cancer is a leading cause of cancer mortality worldwide. Complete resection of esophageal cancer and adjacent malignant lymph nodes is the only potentially curative treatment. Accurate preoperative staging and assessment of therapeutic response after neoadjuvant therapy are crucial in determining the most suitable therapy and avoiding inappropriate attempts at curative surgery. Computed tomography (CT) is recommended for initial imaging following confirmation of malignancy at pathologic analysis, primarily to rule out unresectable or distant metastatic disease. With the advent of multidetector CT, use of thin sections and multiplanar reformation allows more accurate staging of esophageal cancer. Endoscopic ultrasonography (US) is the best modality for determining the depth of tumor invasion and presence of regional lymph node involvement. Combined use of fine-needle aspiration and endoscopic US can improve assessment of lymph node involvement. Positron emission tomography (PET) is useful for assessment of distant metastases but is not appropriate for detecting and staging primary tumors. PET may also be helpful in restaging after neoadjuvant therapy, since it allows identification of early response to treatment and detection of interval distant metastases. Each imaging modality has its advantages and disadvantages; therefore, CT, endoscopic US, and PET should be considered complementary modalities for preoperative staging and therapeutic monitoring of patients with esophageal cancer.

Esophageal cancer: A Review of epidemiology, pathogenesis, staging workup and treatment modalities

“…With any form of ultrasound the accuracy of the study is operator dependent. Also, in cases of esophageal cancer where the esophageal lumen has been narrowed by strictures or stenosis, it may not be possible to pass the endoscope through to visualize the entire tumor [30] .…”

“…The presence or absence of distant metastasis will be essential in guiding treatment options and in determining operability. Common sites of distant metastasis include liver, lung and bones [30] . and overall prognosis, many modalities have been utilized to accurately establish T Stage.…”

“…and overall prognosis, many modalities have been utilized to accurately establish T Stage. These options include computer tomography (CT), endoscopic ultrasound (EUS) and 18 F-fluorodeoxyglucose positron emission tomography (FDG-PET scan) [30] .…”

Radiotherapy response evaluation using FDG PET-CT—established and emerging applications

“…23 Use of interim post-CRT FDG PET-CT prior to surgery can help guide appropriate further management (Figure 2), specifically by identifying interim metastatic disease (which may occur in up to 17%) preventing futile surgery. 24,25 The added benefit of surgery for those with complete metabolic response (CMR) is less well defined. A substantial minority (20-30%) of patients with resectable disease have a complete pathologic response (CPR) to CRT.…”

Hybrid PET/CT and SPECT/CT Imaging

“…EUS and PET/CT independently affects treatment decisions, indicating complimentary and necessary roles in the staging (Walker et al, 2011). PET/CT is not sufficiently reliable in the individual patient for monitoring of treatment response but effective in detecting recurrent disease (Weber et al, 2001, Munden et al, 2006, Bruzzi et al, 2007, Kim et al, 2009). …”