Joint Program in Nuclear Medicine

PET Imaging of Esophageal Carcinoma

Hossein Jadvar, MD, PhD
Alan J. Fischman, MD, PhD

November 17, 1998

Presentation

A 70 year old male presented with chief complaints of hiccups and dysphagia. Previous work-up included an upper GI contrast study that was reportedly abnormal. A CT scan of the chest and a [F-18]fluorodeoxyglucose(FDG) PET scan were obtained.

Imaging Technique

Chest CT: Axial images with intravenous contrast enhancement.

FDG PET: Attenuation-corrected imaging (Scanditronix PC-4096, Sweden) of the chest and upper abdomen was performed 45 minutes after intravenous injection of 11 mCi FDG.

Imaging Findings

Chest CT

Chest CT: Diffuse thickening of distal esophagus (arrow).

FDG PET (coronal and sagital)

FDG PET: The distal esophagus shows abnormal hypermetabolism as demonstrated on a series of coronal images (arrows ) and a sagittal image (arrow). No other abnormal foci are seen.

Differential Diagnosis

The differential diagnosis of a diffusely thickened and hypermetabolic esophagus include carcinoma (squamous cell, adenocarcinoma, adenoid cystic, mucoepidermoid, adenosquamous, oat cell), sarcoma (fibrosarcoma, leiomyosarcoma, rhabdomyosarcoma), lymphoma, melanoma, metastatic disease, and infectious (e.g. bacterial, viral, fungal) or non-infectious (e.g. post-radiation) esophagitis.

Diagnosis

The patient underwent esophagoscopy with biopsy that demonstrated moderately-differentiated adenocarcinoma. He then underwnt left thoracoabdominal esophagogastrectomy and pyloromyotomy.

Discussion

Studies have demonstrated that FDG PET is useful in the evaluation of patients with esophageal cancer at the time of initial staging and at the time of post-therapy re-assessment (1-3). PET is able to visualize the primary tumor and determine the extent of disease including the presence or abscence of hepatic metastases. It may detect unsuspected metastases that are missed by conventional imaging, thereby affecting clinical management (2). Flanagan et al. also showed that PET is more sensitive than CT for revealing regional and distant metastases (3). These investigators considered PET as a cost-effective imaging procedure that may decrease the number of unnecessary surgeries by identifying patients who have unresectable disease (3). Specific uptake value (SUV) has also been shown to not only distinguish malignant tumors from benign lesions but to provide information on prognosis (1). High SUV levels (greater than 2.5) are usually associated with malignancy and the higher the level, the poorer the prognosis. However, it must be noted that false positive PET may result with infectious esophagitis and early after radiation therapy due to radiation-induced inflammation.

References

1. Fukunaga T, Okazumi S, Koide Y, Isono K, Imazeki K. Evaluation of esophageal cancers using fluorine-18-fluorodeoxyglucose PET. J Nucl Med 1998; 39(6):1002-1007.

2. Luketich JD, Schauer PR, Meltzer CC, Landreneau RJ, Urso GK, Towsend DW, Ferson PF, Keenan RJ, Belani CP. Role of positron emission tomography in staging esophageal cancer. Ann Thorac Surg 1997; 64(3):765-769.

3. Flanagan FL, Dehdashti F, Siegel BA, Trask DD, Sundaresan SR, Patterson GA, Cooper JD. Staging of esophageal cancer with 18F-fluorodeoxyglucose positron emission tomography. AJR 1997; 168(2):417-424.

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J. Anthony Parker, MD PhD, Tony_Parker@bidmc.harvard.edu